“Formal education will make you a living; self-education will make you a fortune .”
– Jim Rohn
10.2 Overview of Remote Labs
10.3 Remote Lab Consortia
10.4 Electrical, Electronics and Industrial Automation Engineering
10.5 Mechanical and Manufacturing Engineering
10.6 Chemistry, Chemical and Process Engineering
10.7 Nuclear Engineering
10.8 Information Technology (IT)
A number of remote lab applications are described below. These vary from the simple to fairly complex. The following chapter will take up the issue of optimizing the design of remote labs and their different architectures.
Initially, an overview of remote labs will be given followed by a listing of the significant remote lab organizations or consortiums (generally not-for-profit or university-based). Finally, a reasonably exhaustive review will be given of the various remote lab applications. These applications are broken down into:
• Electrical, Electronics and Industrial Automation Engineering
• Mechanical and Manufacturing Engineering
• Chemistry, Chemical and Process Engineering
• Nuclear Engineering
• Information Technology (IT)
Note that these categories are not tightly defined; hence you will find overlap between the different disciplines in the discussions below. By virtue of perhaps ease of setting up and familiarity of practitioners working in related areas, there is a preponderance of electrical and electronics applications.
The following section provides an overview of remote labs, followed by a list of those organizations active in this area. The different applications of remote labs will be detailed, commencing with electrical, electronics and industrial engineering through mechanical and manufacturing engineering and concluding with Information Technology and miscellaneous applications.
10.2 Overview of Remote Labs
Remote labs range over many discipline areas and in many cases are considered simple remote access of equipment. Some have questioned whether remote labs and simulation can ever replicate real world experimentation feeling that, “Practical education needs to be based on errors and irregularities, as occurs in mechanical, electrical or chemical systems, as opposed to the ideal icons and environments represented on a computer display”. They were also concerned about the lack of re-use of virtual and remote labs at universities. They stated that three words summarized a requirement for a hands-on open lab: ”reusability, simplicity, and flexibility.”1 If remote labs are to succeed they need to embrace this approach.
There have been many examples of remote labs including a spectrometer, digital electronics lab, computer vision system and a transmission electron microscope. Many pundits believe that remote experimentation cannot be considered a substitute for real experimentation and experience shows that students really enjoy real practical tasks.
University of Melbourne scientists have been operating an electron microscope in Sydney remotely using telepresence where they manipulate and observe a real and distant object.2 This allows them easy access to an expensive piece of equipment.
A wind tunnel was used where the students and instructor connected from a remote site and performed all the tests with no operators being present.3
A lab was created for experimenting with intrusion detection (IDS) and intrusion prevention (IPS) technologies with 16 lab PC hosts and 24 students broken into two groups with different schedules so as to maximize the use of the equipment.4 The need to reset the computers after the students’ use and a broadb and service were identified for successful operation.
An example of a remote lab where expensive lab equipment had to be shared was for an electronic design course in a remote-user and time-sharing mode5 An interesting wrinkle with a remote vehicle lab was to build in additional safeguards to protect the lab hardware from damage by the vehicle being remotely controlled by the student.6
An interesting application of a remote lab was the use of a telescope. Here, the web interface of the instructor who was directly connected to the telescope was passed to (or his application shared) with that of the student. As the student described the process:
…Ron used application sharing to show me how to use the Web interface that controls the telescope…. I set the shutter speed and snapped pictures! The live nature of the session allowed us to examine each picture right on the spot”. The immediate support and feedback from the instructor to the learner with hands-on interesting activities made for an outstanding online learning experience.7
Figure 10.1: Remote Lab Based around a Telescope
A novel remote lab comprised a datalogger that gathered various items of meteorological data (air temperature, humidity and wind speed) and could be accessed by students situated remotely. However, there were concerns about verifying of the student’s resultant knowledge and practical skills.8
The Stevens Institute of Technology have set up a system of remote labs that can be accessed anywhere at any time, thus allowing the students considerable flexibility, unlike a traditional lab. Remote labs can reduce costs and are safe for the student, at least.9
An example of a remote lab, at Florida Atlantic University, was used for electrical element characterization (to examine the current voltage relationships for various electrical elements). A data acquisition board was set up in a lab; the student could then remotely wire in different components on the attached configurable breadboard and then select a sequence of current values to be injected by the data acquisition board analog output into the resister. The corresponding voltage drop is then read from across the resistor by the analog input module for the student to read.10
A robotic arm remote lab was used successfully to demonstrate the key principles of motion control. The learners used their theoretical notes to get up to speed on the subject (for example, the terminology where you were exposed to concepts such as degrees of freedom, rotation angles, etc.). They then interacted with their tutor in grasping the essentials, and were given access to the robotic arm so that they could then underst and the different degrees of freedom that an arm exhibits. Most importantly, they were also exposed to their classmates’ work and shared their experiences and knowledge. Overall, having a practical example of the subject, makes for an outstanding learning experience as opposed to purely theoretical.11
At the Department of Electrical Engineering, National University of Singapore, remote labs were applied to demonstrate the use of an oscilloscope, in measuring phase shifts, examining the frequency response of a low pass filter and the transient response of a series RC circuit.12
Suggested Remote Lab Topics
Some suggested remote lab topics.13
Table 10.1: Suggested Topics for Effective Remote Labs
|Electrical & Electronics Engineering||Mechanical Engineering||Data Communications & Networking||Civil Engineering||Chemical Engineering|
|Verification of Kirchhoff’s Current and Voltage laws||Impact of jet of water||Serial data communications networks||Tensile testing of metals||Processing plant|
|Half and Full wave rectification||Vapor pressure||Industrial Network Security||Triaxial shear tests on soils||Heat transfer|
|Transistor amplifier circuits||Minor and major losses in pipes||Routers, switches and gateways||Concrete compression testing||Mixing operations|
|System Frequency response||Extended Surface heat transfer||Dynamic response of structures|
|Motor Control||Tensile testing||Viscoelastic behavior of polymers|
|Audio Signal Processing||Vibrations of a 2 degree of freedom system||Moisture/aging impacts on materials|
|Electrical Harmonics and Power Quality||Fatigue response of materials|
|Digital Signal processing|
|Programmable Logic Controller programs & operation|
|PID loop process control operation|
This table was adjusted from that of Table 1: Typical Physical Laboratory Exercises in Civil, Electrical and Mechanical Engineering as per reference.13
Other examples of remote labs range from semiconductor characterization, electrical element characterization, logic design, control, electric motors, image processing, telecommunications, FPGAs, optic circuits, antennas for Electrical and computer engineering; motion, friction, tensile testing, speed of sound testing (mechanical engineering) and speed of light measurement, electron diffraction, voltage current characteristics, interference, photonics and fluid mechanics (physics).14
A more detailed examination follows of typical remote labs in the different discipline areas of engineering. The optimal architecture and theory behind remote labs will be examined in the next chapter.
10.3 Remote Lab Consortia
A single university or institution is unlikely to be able to provide a single point for remote or virtual labs to satisfy any one syllabus.15 Students are unlikely to go directly to a remote lab site but tend to prefer to work through their LMS portal (as a central point) to access a specific experiment.
It is vital to develop a pool of remote labs on an international basis to increase the availability of labs and to proffer opportunities for students in varied countries to collaborate with each other in lab experiments.16 In today’s world, engineering graduates need to be able to negotiate meanings across languages and cultures or to be interculturally capable.
There are a number of different remote laboratory management systems providing support for groups of remote labs.17 These include iLabs Shared Architecture (from MIT), WebDeusto, LiLa and Sahara (Labshare)–all discussed below.
Arguably one of the most famous examples of a remote lab initiative are that of the iLabs, started by MIT (and sponsored by Microsoft) in 2000 with a microelectronics device characterization test station, a dynamic signal analyzer, a heat exchanger, a shake table and a polymer crystallization lab. Up to December 2006, a reported 4500 students worldwide had taken for-credit course assignments using iLabs. The source code has been made freely available to everyone to use.18
Australian Labshare Project
The Labshare Institute was initiated to highlight and demonstrate the use of remote labs (or “remotely accessible laboratory technologies within the education sector” as they state so aptly on their website labshare.edu.au). Refer to the resources contained on their website, which ranges from a glossary of terms, a literature review of remote labs, a commentary on engineering accreditation criteria, and (most importantly) sample lesson plans and evaluation questions for the currently available lab rigs.19 It was anticipated that over 4,000 students from nine Australian universities would be participating in the labshare project during 2010 and 2011, and considerably more research findings would thus be derived.
Global Online Laboratory Consortium (GOLC)
An international group of universities creating online labs have formed the Global Online Laboratory Consortium (GOLC). A meeting was held in January 2009 with participants from fifteen universities in the USA, Africa, Australia and Europe to establish a consortium to promote and implement online labs and supporting infrastructure and scholars initially based on the iLab Shared Architecture developed at MIT.20 The iLab framework has two different types of labs: Batched and interactive. Batched experiments are where the entire experiment parameters are defined before execution of the experiment, whilst interactive ones are performed online in real time.
Three prominent labs included in the GOLC grid were:
• A remote Application Specific Integrated Circuit (ASIC) design and test system where users can experiment with real chips.
• A remote digital systems laboratory allowing users to perform experiments with a Complex Programmable Logic Device (CPLD).
• An image processing lab where the users have to develop an autofocus algorithm using LabVIEW.
Deployment of the VISIR
The Department of Electrical Engineering at the Blekinge Institute of Technology in Sweden set up a remote lab project in 1999 to duplicate the traditional hands-on lab workbench for electrical experiments (e.g. for electronic operational amp experimentation) called the VISIR (Virtual Instrument Systems in Reality). This remote lab software is disseminated as open source software.
The VISIR is being used at three other universities: University of Deusto (Spain), Polytechnic Institute of Porto (Portugal) and Spanish University for Distance Education (Spain).21 At the Faculty of Engineering University of Deusto, it is used in telecommunications, computer science, industrial technologies and electronics. In a survey, the students regarded the VISIR as an excellent support tool. The Polytechnic Institute of Porto initially applied it on the applied physics course of the computer science engineering degree with positive feedback from students. It has since been extended to six different engineering degrees. The Spanish University for Distance Education initially accessed the University of Deusto remote labs for the electronic circuits and components course with circuits such as half-wave rectifier, regulator with zener diode, operational amplifiers and BJT transistors; again with positive feedback from students. It has now been installed within their own labs. The long term plan was to set up a network of remote labs at partner universities to increase the scalability of the labs and to increase the range of implementation.
The LiLa (Library of Labs) project is a European Union-funded project to set up remote and virtual labs.22 The concept is that LiLa partners can collaborate with each other in using each university’s labs in presenting their lectures. It was noted that many universities in Germany have a challenge with students being unable to fit in labs into their busy lecture schedules.
There are differences between LiLa and some of the other initiatives to create online labs. Both iLabs and Labshare specify the software infrastructure for their labs, while LiLa defines the interfaces required to build a repository of labs without detailing their architecture.
Another initiative, Lab2Go, details references to online resources while LiLa provides an online repository where students and instructors can download the required resources.
10.4 Electrical, Electronics and Industrial Automation Engineering
Remote Electronics Lab with Electronics Workbench
Tisdale described the use of a lab with the electronics simulation tool, Electronics Workbench. Here they set up the simulation software package, Electronics Workbench, on a central server which students accessed remotely using Microsoft’s Netmeeting. Electronics Workbench provided simulation of such items as resistors, capacitors, inductors, op amps, logic chips, dc, and ac stepper motors. They found that it was unsuitable for beginning students who had no comprehension of working with real components but for experienced students it was a great way of illustrating basic principles especially being freely available. It was important for the instructor to be available and to ensure the students knew that only one person could use the central server housing the simulator at any one time. There were some significant security problems experienced in using Netmeeting with and due to this problem students off-campus were not able to access the simulator. Other challenges with Netmeeting were that it was quite resource hungry on the CPU, but this was described using an early version of Netmeeting with a considerably less powerful PC.23 Presumably performance has improved since then.
Remote Electronics Laboratory
A remote controlled instrumentation lab was used to teach electronics to information engineering students called ISILab (Internet Shared Instrumentation Laboratory). Typical labs conducted here included delays in digital circuits, gain and distortion of amplifiers using a waveform generator and oscilloscope. A Real Laboratory Scheduler (RLS) manages each experiment, scheduling and serving multiple users at a time. There is, however, no booking facility provided. Each user doesn’t need any software or hardware to access the experiments, merely a web browser and Java Virtual Machine. Electronic switch matrices are used to switch the different circuits into action and perform the measurement. A specific circuit stays connected just long enough to perform the measurement. Using time sharing, multiple users can thus access different experimental configurations. Each experiment has an associated set of documentation for the experiment including:
• The theoretical concepts behind the experiment.
• Objectives of experiment.
• Results expected.
• Description of the equipment used.
• The detailed experiment’s description.
A webcam provided a video view of the experiment.
The number of switches in the matrix increases exponentially as the number of components increase, so this makes for a limited experiment. Due to the contact resistance of each switch, the signal quality does tend to degrade through several switches. This necessitated adopting an approach with a motherboard and 16 slots where a specific type of circuit is built for experimentation. The circuit board is then connected up dynamically to 18 lines (5 lines for the power supplies / 1 line for input signals / 3 lines for output signals and 8 lines for circuit identification). Instrument virtual panels are the graphical user interface to allow the student to interact with the real devices (with knobs, menus and waveform charts).
In conclusion, the designers remark that remote labs probably can’t replicate the experience of a traditional lab; for example, construction of a prototype circuit. However, the evolution of hardware technology makes it less and less likely that an electronic circuit is built from scratch. So this remote lab approach is certainly valid and usable.24
Remote Laboratory with an FPGA Board
A remote lab was constructed using the client-server approach, with eight remote servers each connected to a field-programmable gate array (or FPGA board). An FPGA is an integrated circuit which can be configured by the designer using a hardware description language (HDL). The FPGA can be used to implement any logical function that the previously popular ASIC (Application Specific Integrated Circuits) chips could do. After the student has prepared his or her design using the relevant software design tools, the design is reconfigured on a remote server. There are eight servers available, each connected to a FPGA board with I/O capabilities. There are two sets of practical sessions. The simpler set is based around 8-bit switches and LEDs, 4-bit pushbuttons and LCD displays. The second set of practical sessions is aimed at more advanced designs and uses lab equipment including signal generators and oscilloscopes. The student would select the appropriate test equipment to use. Certain pins on the FPGA board are allocated as test I/O pins (and physically connected to lab equipment) so if there are more test points than test pins, a multiplexing unit needs to be selected and set up in the FPGA design. There was some degree of unhappiness by the students in the difficulty of making an easy connection to a remote lab, but this was apparently because of only provision of verbal instructions on what to do, resulting in the usual misunderstandings. Help menus and tutorials are planned to minimize this problem in future.
Initially, LabVIEW from National Instruments was used but was discarded in favor of a (claimed) lower cost, quicker expansion and continuous updating ability software solution.25
From an engineering point of view, it has been suggested that based on the experience that online learning technology has evolved from following this sequence: boring online self-study, online courses with static visuals, web conferencing with minimal interaction from learners using web casting, interactive web conferencing, simulation of experiments to practical experiments using remote labs.26
Integrated Circuits Testing
Integrated Circuits Automated Test Equipment (for testing of System-on-a-chip) can be an expensive proposition with a Verigy V93K System costing over one million Euros.27 A solution was to share the equipment both locally and remotely through the National Test Resource Center of the CNFM at the University of Montpellier in France. Besides those sourced from France, users have come from countries such as Germany, Spain, Italy and Slovenia. The test software (SmarTest) is based on the Eclipse open platform.
Remote clients have the option of connecting directly to the lab’s Linux stations using the VNC software or of running the SmarTest software locally on their machines (especially useful if latency of the link is an issue). The typical test program has a number of steps: Defining the pins, defining the levels and timings, defining the vectors and then in debugging the functional test (with a pass or fail). The tester usage has reached 80% of working hours for the first quarter of 2009 with about 100 students each year accessing it.
Mixed Reality Remote Lab
A remote FPGA lab was constructed with a virtual 3D image of the board (using Unity3D) to make it look more realistic to the user (such as reading codes on the chips).28 An interactive layer was added to the board comprising switches, lights and messages for the user. There are thus opportunities in using augmented reality in the design of a remote lab.
Robot and Programmable Logic Controller (PLC) Lab at Elizabeth City State University
A remote lab was set up in the Department of Technology at Elizabeth City State University with a Scorbot-ER 4U Robot, an Allen Bradley SLC 500 Programmable Logic Controller, a host programming computer and a Logitech web camera, all connected on a common LAN.29 These are accessed from a remote computer that has to configure the RSLogix PLC programming software and Scorbase robotics software located on the host programming computer.
Figure 10.2: A Typical Remote PLC Lab
A VPN network was setup between the remote client computer and the host programming computer to ensure adequate security. A static IP address was assigned to the host computer and the remote computer connects to the host computer via a secure VPN channel. Some of the limiting items that were noted included the speed of the network (1MBps for the internet); the host computer USB port needed to be fast and a range of static IP addresses was suggested (to set up a VLAN). Finally, the latency of 10 to 20 seconds to complete a requested action from request at the remote computer to the automation system performing the action was considered fairly lengthy and unacceptable. This is a significant latency and was likely to irritate a student, but it was unclear if it is mainly due to the communication system (which can be certainly improved) as opposed to the action of the automation system (where it may be more difficult).
Overall, the remote lab was considered successful. A few future improvements noted were to improve the speed of operation (presumably reducing the latency), increased flexibility, an improved camera with 360º viewing capabilities and a miniature camera on the robot arm so that the gripper of the arm can be viewed in more detail.
Measurement and Instrumentation Remote Labs
Three experimental rigs were set up at Fort Valley based around National Instruments (NI) data acquisition boards and LabVIEW software as follows:30
A motor generator station that has a three phase ac motor driving a dc generator. The motor is driven by a variable voltage, variable frequency ac inverter. A National Instruments (NI) board has an analog output which controls the speed of the motor. A speed indicator comprises a photosensor detecting moving strips of reflective tape on the coupling between motor and generator, and thus sending a pulse train to a frequency signal conditioner. A reaction torque sensor measures the torque on the generator. Five temperature sensors monitor the temperature at various places on the unit.
A pump flow level system comprised a dc motor-driven centrifugal pump that pumps water from a reservoir to a gravity drained receiving tank. The gravity drained receiving tank drains back to the reservoir. The flow rate is measured by a paddle-wheel flow meter. The pump speed is also controllable. The height of liquid in the tank is measured with a pressure sensor. A pipe allows for draining of a controllable amount of liquid out of the tank.
A heat transfer station comprises a soldering iron connected to a long rod which has thermocouples connected to it along its length. There are a number of rods of different metals that can be selected.
The first two stations are entirely controlled from the web via a remote computer also running a run-time copy of LabVIEW which accesses LabVIEW running on the laboratory computer connected to the test rigs.
The overall feedback from students was positive–especially considering the time to run the labs and the flexibility of location in which to site the remote computers to conduct the experiments.
Use of Multisim with an Online Lab
The beauty of using Multisim with a lab kit (such as ELVIS II from National Instruments) is the ability to compare simulated and real data from electronic circuits.31 Multisim allows one to work with both analog and digital components in a spreadsheet environment with traditional SPICE analyses and the ability create interactive parts (such as switches and potentiometers) to dynamically change the simulations. Hence, Multisim can be used to practice prototyping in a simulated environment and then use a portable onsite lab (comprising data acquisition system and circuit training board, such as ELVIS II) to test out the results of the simulation in a real environment.
Automated Lab Test Environment for Electronics
In the Engineering and Technology programs at the University of Hartford, an “Automated Laboratory Test Environment (ALTE)” was set up.32 The concept wasn’t to replace existing labs but rather to supplement them on a 24/7 basis due to the overload in terms of burgeoning student demand.
The architecture comprised three modules: a web-based database managing student access and the lab resources, a lab PC (with LabVIEW) and the hardware/instrumentation that collected data from the DUT (Device Under Test) which formed the specific experiment being undertaken. The lab PCs, with a pre-developed LabVIEW virtual instrument panel (which broadcasted the interface on the web so that the remote students could interface to the equipment), were set up with different collections of equipment such as an Agilent DMM, function generator and oscilloscope, National Instruments’ Educational Laboratory Virtual Instrumentation Suite (ELVIS) and custom data acquisition hardware.
Lab procedures were written and uploaded to the ALTE by the lab instructors and were detailed enough to show students how to access the remote labs and to operate the virtual instrument controls.
Two labs each were created for two fundamental electronics courses. These were Series RL circuits and parallel RL circuits (ac Electrical Fundamentals) and Digital gates/combinational logic and J/K Flip Flop circuits (Electrical and Electronic Fundamentals). Each student was limited to 2 hours per session.
The results were mixed. 22 of the 31 students undertook 33 distance labs sessions mainly over the period from 1pm to 5pm and 8pm to 12pm. The number of students dramatically reduced on the second and subsequent distance labs. The lab report grades were similar for both online and remote labs. Students strongly preferred the on-site labs. There was an equal split between those who saw value in remote labs and those who felt that the remote labs exercise shouldn’t be continued.
Some suggestions from the students were to embed a circuit diagram on the virtual instrument panel to make it more obvious what was being tested. Other suggestions were that remote labs are useful for “predict and measure” labs compared to on-site labs that focused on design and troubleshooting.
Applied Engineering Technology Labs
A selection of remote labs for applied engineering technology students from Drexel and associated community colleges was put together.33 The first comprised an electronics lab introducing students to the fundamentals of ac/dc circuit analysis, analog and digital electronics and the fundamentals of microprocessors using LabVIEW. The second lab undertook Non-destructive testing of Materials (NDE) such as aircraft wing sections and rocket motors. The NDE transducer positioning system was completely computer controlled and the output image and analysis was performed via computer. The third lab was a robotic assembly station using four Yamaha robots for pick and place operation. Students programmed, debugged and tested the robots remotely. The initial tests with pilot lab sessions at outlying community colleges and Drexel university were successful with estimated annual savings of the order of $24,000 per course.
Fiber Optic Education using Simulations, Videos and Remote Labs
The Universities of Houston and Colorado developed three remote lab experiments for a Fiber Optic Communications course.34 There were three parts to each experiment: a simulation, a pre-lab video and an interactively remote controlled and monitored experiment. The simulation allowed a student to perform experiments by varying various parameters of a model and observing the results. The pre-lab videos illustrated the procedures that had to be followed in each lab.
Simply placing static materials on a website was avoided as this was considered not to have the same educational benefits as that of an interactive video streaming presentation with students interacting in real time with (live) instructors. It is conceded that a highly motivated student may be more enthusiastic about listening to a video streamed presentation at their convenience rather than at some fixed time.
Optical fiber dispersion and the receiver noise figure are two important parameters in the design process and the simulation tool allowed one to examine the trade-offs. The simulation tool was based around LabVIEW–it is easy to download a free copy of the runtime engine to use this tool. The front panel of the virtual instrument allowed changes to bit rate, linewidth, fiber core, cladding dimensions, indices, receiver noise level and amplification. The resultant output is an eye-diagram and bit error rate (BER).
The remote lab comprised a PC-based optical time domain reflectometer (OTDR) that could be controlled via LabVIEW using the virtual instrument panel. A live video feed of the OTDR display confirmed the readings on the virtual instrument panel and helped to add more realism and confidence to the lab.
As the authors point out in another paper, it is hard for the instructor in assessing students working in remote labs.35 They note that remote labs today reflect the increasing move of manufacturing facilities to being remotely monitored and controlled. A survey was conducted of students on these remote labs and 83% indicated that they found remote labs and residential labs gave them similar confidence. 55% of students found the webcam gave a positive impact on their confidence in dealing with the labs (against 45% who were neutral).
It is pointed out that nowadays, modern test and measurement is often performed remotely so this lab is a reasonably realistic representation of the real world.
Typical Commercial Remote Lab Hardware for Wireless
The rapid growth of wireless technology (e.g. 3G cellular, industrial wireless and wireless sensor networks) is a fertile ground for labs and there are a few well-known commercial offerings in this area offering remote access to a student.36 EMONA Instruments offers various hardware-based communication systems such as the TIM-301/C System Unit which has fixed plug-in modules such as master oscillators, buffer amplifiers and optional plug-in modules such as adder, multiplier and phase shifter providing a wide range of communications experiments. An additional module (net*TIMS) is simply plugged into to this system unit and connected to a net*TIMS server. Users log onto a standard browser and receive a Java-based client relative to the specific experiment. The cost of net*TIMS is high ($30,000) and the number of experiments is limited.
Other options include National Instruments RF/Communications combination based around the LabVIEW package and an eight-slot PXI chassis, RF (Radio Frequency) signal generator, RF signal analyzer and embedded PC controller. The LabVIEW pages can be published on the web where one student at a time can manipulate objects (and the other can only observe).
A survey conducted on students who had undertaken the Amplitude Modulation Lab rated the overall lab as excellent or good (approx. 90%).
Electronic Technology Labs using a Switching Matrix
At the Oregon Institute of Technology, the second-year (or sophomore-level) students undertaking analog electronics classes have associated lab classes where they do h and calculations, computer simulations and experiments on a range of electronic circuits. Five remote labs were constructed for mature age professional students to access as part of their distance learning.37 The same experimental setup and electronic devices were used as in the normal classroom-based physical labs. The only exception was that the dc power supplies were hardwired to avoid the students damaging electronic components in error. The ubiquitous National Instruments hardware and LabVIEW software were used. Two labs were initially set up based on the Operational Amplifier and MOSFET integrated circuit chips. The part of the remote lab that made it particularly useful was the switch matrix (and terminal block) of 512 micro-switches that are arranged in an 8-row by 64-column format. The switches were controlled by the matrix controller, which allowed for real electronic components to be selected and then connected into the desired experimental circuit. Although only one student could have control of the circuit at a time, the remaining students could observe. The results were mixed with the student survey indicating between 27% and 45% felt the remote lab was as good as a learning experience as the physical lab. Only 40% to 53% of the students preferred the remote labs. The one heartening result was that over 80% of the students considered them an acceptable alternative for distance learning students. As a result of this work, the remote lab program was to be expanded to also include labs in introduction to amplifiers and semiconductors, transistor amplifiers and frequency response of amplifiers. In addition, a scheduling system was to be introduced to avoid conflicts with multiple students trying to simultaneously access the same lab.
Computer-aided Control System Design Course
A computer-aided control system design course at Michigan Technological University was enhanced with a remote lab.38 The objective of the lab component of the course was to increase the understanding of control system design. The lab designers felt that the students didn’t have a sufficiently deep appreciation of control system concepts and the lab component was considered critical to achieving this. During the initial phase of each lab, MATLAB (with SIMULINK) was used in a variety of different experiments covering linearity, linearization, Laplace Transform analysis, time domain specification-based design, Bode Plots and PID Controller design.
After performing the simulated pre-test of the controller design, the students then implemented it on physical hardware in the lab and compared the theoretical and practical results. There were three main control system hardware experiments: a dc motor driven gear set with encoder feedback, a dc motor driven cart with encoder feedback and finally, a water pump / tank system with tank pressure sensor feedback. Quanser’s weblab software was used to convert the in-class labs to remote ones. Sensor information was streamed to the student web client from the remote lab and this rendered the motion of a 3D model of the hardware. The students learned the interface quickly and were able to collect and analyze the data effectively. The next exercise proposed is to compare the different levels of comprehension of a student undertaking a hands-on experiment vs. a remote lab.
Laser and Fiber Optics Technology Labs
Queensborough Community College set up a remote lab on photonics which was tested by Suffolk County Community College as the remote site.39 Courses in photonics are hugely capital intensive requiring considerable expenditure especially bearing in mind the limited number of students. There were three courses comprising the laser and fiber-optics technology program: lasers and detectors, fiber optics and physical optics. Course materials included interactive multimedia textbooks (with animations, simulations and video clips), lab manuals and the remote controlled lab exercises. The selection of remote lab exercises was comprehensive and included: interferometry, diffraction, polarization, acousto-optics, electro-optics, coupling losses, wave division multiplexing, dispersion and distortion in fibers.
The labs fitted into two categories: those that required movement of objects that were controlled by motorized mounts and those that required control of instrumentation (e.g. Michelson interferometry). An example of an exercise was the use of a Michelson interferometer that was aligned by controlling the horizontal and vertical tilt on one mirror. The alignment was undertaken by observing the fringes using a video camera. The student could control both the camera and motors.
A number of additional hands-on exercises were required which had to be performed in person by the student attending the college (on a Saturday, for example). The results showed that the lab manuals needed to be significantly improved for the distance learning students. When the instructor is on-hand, as during a normal class session, defects in a lab manual are easily dealt with. This is not the case with distance learning students who don’t have immediate access to an instructor. The naming of equipment in the lab instructions also needed to be made more idiot-proof and transparent. When these changes were affected and tested on the distance learning students, the average grade was higher than the local residential students. However, it should be born in mind that this sample was small and the students were likely to be self-selecting.
Remote Lab based on Programmable Analog Device
The ispPAC10 (from Lattice Semiconductor) is a programmable analog chip allowing for the implementation of several analog circuits such as low-pass and band-pass filters, amplifiers and oscillators.40
Two similar remote labs were set up based around this chip at the Carinthia University of Applied Sciences (Austria) and Princess Sumaya University for Technology (Jordan). Experiments were conducted at the server side where experiments could be controlled over the internet by changing parameters on the input signal such as waveform, frequency, amplitude and offset. The outputs from the chip would then be compared to the inputs.
The architecture of the system comprised a LabVIEW server with a NI Data acquisition board. The LabVIEW server published the front panels of the virtual instruments allowing for remote access (through a browser and the LabVIEW runtime engine). The PAC-Designer software for programming the ispPAC10 chip was installed on a Citrix server that could then be remotely accessed in creating circuit schematics and uploading the design. The data acquisition board could then be configured remotely via the remote instruments (function generator and oscilloscope). Some limitations were that the function generator could not generate the signals within a large bandwidth and low amplitude signals (0.1 to 0.2V) noise was noted. This was remedied by using a cable with individually shielded analog twisted pairs.
Electric Drives Lab
A remote electrical drives lab was set up at the Electrical and Computer Engineering Department at the University of Minnesota.41 Generally speaking, students are not familiar with labs and lab equipment with relatively complex measurements required. The tight time restrictions in working in a lab add to the pressure. The approach described below was considered a great way to overcome some of these challenges.
A remote lab based on real electric drives was set up using Adobe Breeze, MatLab Simulink and Real Time workshop as well as dSPACE and Control Desk. The simulation software tools allowed the students to compare results with the real experiments and (hopefully) illustrated that there is a chasm between real world lab experiments and equipment and a neat computer simulation. Adobe Breeze allowed for web conferencing and application sharing of a real world application. Matlab Simulink was used to build real models and the Real Time Workshop generated the C-code. dSPACE was used for testing and verification of the motor control algorithms generated by Simulink. Finally, Control Desk was used to create virtual instrument panels and allowed the student to manage the entire experiment.
The lab had six terminals, one of which had all the equipment (including machines) and the others with all the software installed (without being connected to any machines). Typically in a lab, there were 10 students broken into five teams. The instructor passed control to the students in a Breeze virtual meeting room. The students built the simulation models and all worked together on setting up and running the experiment on the one machine. The instructor shared her terminal desktop with the other students and they then performed the experiment using Control Desk. The students were then expected to compare the results from the simulations and the real equipment. They could also work individually from their own PCs performing the simulations and then screen sharing with the other member of the team.
The difficulties that were experienced are that students have difficulty in visualizing the physical electrical machines in operation. Providing recordings of the labs can obviate this problem. In building a large number of Simulink components, delays were experienced in sharing screens between students leading to some irritation, but students adjusted to this delay.
The advantages with this approach are reduced expensive hardware requirements of lab equipment. One hardware setup (and a back up) is all that is required when using these as remote labs. The lab sessions could also be recorded allowing the student to prepare and reflect on the lab more effectively. In using computer-based collaboration between the students, the integrity of the course could be improved as a more accurate assessment could be made of a student’s work.
Multi-circuit Switching Board
At Western Michigan University a matrix switching board based around a web-based server was built (based on an AMD microcontroller).42 The microcontroller allowed the setting and resetting of up to sixteen dedicated TTL signals that then control the matrix board relays.
A virtual breadboard was populated with three resistors and two power supplies. A user could then drag any components around the breadboard to achieve a certain wiring circuit. The SUBMITT button was then pressed by the users to clear previous settings and to then set up the new desired setting of leads to nodes.
Remote Lab with LabVIEW
As discussed above, working in a laboratory is a key element of engineering education. A remote laboratory was set up at the University of Hong Kong Electrical and Electronic Engineering Department using LabVIEW with virtual instruments such as digital multimeters and an oscilloscope, and associated hardware for 50 undergraduate electrical and electronic engineering students.43 The survey results indicated that these labs were considered more suitable for senior students and should preferably be used in conjunction with traditional labs. In addition to the normal listed advantages of remote (and virtual) labs, it was believed they increased students’ enthusiasm for learning through interactivity, and improved IT literacy. Industries are increasingly using simulation software, so it is important for students to gain expertise here. Finally, use of remote or virtual labs easily provides attendance information as well as quick feedback and assessment. In addition, to the disadvantages listed earlier, it was suggested that remote access discourages team work and there is an increased risk of plagiarism.
Optical Circuits Laboratory
The Engineering Technology Department at the University of Houston and the Electrical and Computer Engineering Department at the University of Colorado (Boulder) described a remote labs offering for an optical circuits course covering understanding and operating optical components and their associated test and measurement instruments. They felt that this course was important because of the lack of knowledge on fiber optic transmission systems, optical detection and bit error rate issues. One of the key issues, as pointed out here by the authors is to separate the imperfections between the technology and the actual teaching aspects of the lab.44
They pointed out that the imperfections in their remote lab technology related to the connection speed from the client browser to the remote lab. Whilst there have been no problems with the speed from the student client browser to the lab, there have been delays of up to 2 secs in switching from one setting to another (e.g. LED to laser transmission) and in addition, the server has “frozen”. The second imperfection related to the data acquisition software (LabVIEW), perhaps relating to inefficient instrument drivers. The third issue has been a requirement for more controls on the remote lab interface, but there are some concerns that this may make the interface too complex.
The second set of imperfections related to the teaching of the course and use of the lab. Before commencing, the students attended a video of the lab and then undertook a simulation. The idea behind the video was to provide an overall picture of what is happening and help familiarize the students with the equipment and setup. Imperfections were considered to be the orientation video, the lack of troubleshooting practice in the remote lab and the possible mismatch between the simulation model and the real-life experiment.
The student surveys at the conclusion of the experiments indicated satisfaction in conducting the experiments with most students comfortable with the interface to the real instruments. There was some degree of unhappiness with the remote control panel software. Although it’s difficult to gauge from the survey whether students were actually “dissatisfied”, most indicated that the remote lab did not give a similar experience to that of a real hands-on experiment (56% to 44%). Additional “expert” opinion was equally divided as to whether the lab instructions were sufficiently clear. Interestingly enough, all the experts indicated that there was no requirement for a webcam to control the experiment.
A Competitive Way of Learning Automatic Control45
The University of Siena Engineering Department has created a successful way of encouraging learning in control systems. They have four processes set up in remote labs: A dc motor, level control in a tank, magnetic levitation and finally, a helicopter (two degrees of freedom used in graduate level courses) They pointed out that while virtual labs are good for absorbing theory, remote labs are essential for learning about real world problems such as in dealing with non-linearity issues.
A competition was organized with the students designing a controller (and associated parameters) using Simulink on their own computers (using a pre-defined template they download). They then describe the structure of their controller on the lab site and upload their MatLab file and data. These are then compiled and executed in the remote lab. Another graphical window allows the user to start the experiment and to observe its associated plots. A ranking is then automatically created of all the submissions from students, so that they can see who has submitted the optimal solution. Overall, this was successful and allowed students to apply their theoretical knowledge without restrictions on lab opening or closing times.
eComLab: A Radio Communications Remote Lab
At the University of Texas, San Antonio, a series of remote labs (eComLab) was constructed with three generations of development.46 The first generation comprised TeamViewer and chat and file transfer available. This is a first-in, first-out queuing system with no collaboration possible and clients are required to install software on their machine. The second generation allowed for multi-user access, with uBuntu Linux to provide the web interface from an Apache http server, a MySQL database, separate computers for the experiments (using National Instruments ELVIS data acquisition hardware and Emona DATEx trainers) and streaming real-time video. For reasons ease of access for students, the Blackboard LMS was used to access the lab system. The experiments could be accessed through a standard web browser with no software installation required. Multi-user access was possible, with only one user being able to do the control.
The latest generation allowed for a standard browser to access experiments with all web pages coded in PHP using the MySQL database. TightVNC was used for transmission of the remote experiments. The central server verifies all user credentials and can either host the experimental hardware or connect to other machines.
When the student logged onto the eComLab, they choose the appropriate experiment, discussion board, a survey, and resources area. In the experimental zone, the user has access to update rate of lab, full screen mode and the ability to transfer control of experiment to others.
The instructor is also able to manage the lab remotely with management of materials, experiments and users. Data from surveys indicate that the students believe the improvements over three generations of labs have been positive.
Remote Lab for Collaborative Experimentation at University of South Australia
The authors believe that students have two methods of working together and learning, which they have labelled: collaborative or co-operative learning. Collaborative learning occurs when students make their own decisions about what to learn and how they undertake this process. On the other hand, co-operative learning requires the instructor to drive the learning process by making decisions for the groups on how they will work together and thus learn.47 Engineering projects are characterized by a considerable amount of collaboration with multi-disciplined teams a key part.
A remote lab (the 'Netlab') located at the University of South Australia was set up comprising programmable lab instruments, such as an oscilloscope, function generator and multimeter, connected together with the IEEE 488.2 interface to a lab server PC. An additional feature was the 16X16 programmable matrix relay switch allowing the connection of different electrical components together. The lab server and student client software interface were written in Java. The student client interface conveys a feeling of realism of working with real instruments and the students are able to push buttons and turn dials on the instruments using a mouse. The remote lab was originally written using LabVIEW; currently the Virtual Instrumentation Software Architecture (VISA) API is used to direct commands to the appropriate instruments. Components such as programmable variable resistors, capacitors and inductors can be connected in a lab. In addition, transformers can also be used. An easily configurable camera that can pan, tilt and zoom with its own web server completes the Netlab.
The Netlab allows for up to three users to have control of the lab equipment at any time. Students can book lab sessions for groups of three, two or one individual and are drawn from Australia, Singapore, Malaysia and Sri Lanka. An example of an experimental set up was to create different models of an inductively coupled third order system. Students had to connect together the different components collaboratively using the chat window in the client software to communicate. Once they had obtained the experimental results, they were required to create two theoretical models of the system using PSpice and MatLab. There should be a match between the experimental results from the lab and the theoretical models and this can be quickly ascertained by the instructor. In most cases if there were a mismatch, it would be because a component hasn't been connected correctly.
The authors compared the experimental results (using returned survey results from 60 students to assist in understanding the results) from three groups: remote labs only, the actual lab and a mixture of both. Students generally still preferred to undertake experiments in the traditional lab setting. However, the lab grades of the labs were similar for all groups. The most popular, most time efficient and presumably easiest approach for producing lab reports was for each member to be allocated a clear objective of their work to complete, as opposed to the passing of the lab report to each student in turn to complete his or her portion.
Standard Electronics Lab with Web Kernel48
The main focus of the R-Lab was for electronics experiments. A configurable switching matrix distinguishes it from other remote labs. The R-Lab was based around the client-server model with five components:
• Student clients.
• Internet link.
• R-Lab Server that has Web Kernel software.
• Experimentation Unit.
• Instruments (such as signal generator, oscilloscope and power supply unit) connected to the experimentation unit.
An example of the use of the switching matrix was in conducting operational amplifier experiments and changing the associated circuit elements (e.g. feedback resistors from 10K, 5K and 1K Ohm). Students were generally happy with the lab, but one concern expressed was the slow transmission of images to the client displays. A faster IEEE 488 interface was anticipated to improve response times to correct this problem.
As has been pointed out, these remote labs will never replace the real hands-on experience in a real lab but they can be used to supplement the real labs and to provide more time for familiarization with the labs (perhaps, before conducting the “real” experiments).
A Robotics Laboratory
At the University of Texas, Brownsville, a Bachelor of Applied Engineering Technology program was created based on a set of remote lab experiments comprising robot programming and application development, sensor integration and application, calibration of a vision system, an automated visual inspection system and assembly and color sorting using computer vision.49 The two key components in the remote lab were the Seiko D-Tran robotic system and a DVT vision system. Communications between the Seiko-D-Tran robot and the vision system was through an interface module. The remote user obtained permission from the host computer and then took over control of the robot. Students learn basic programming tasks for robots and vision systems and gained some appreciation of the need for safety when programming devices at a distance. Some improvements are required for future implementations such as the provision of multiple experiments (to reduce queuing), improved bandwidth and operator interface.
Remote Labs for Electrical and Electronic Measurements
The School of Engineering at the University of Salerno, Italy set up two sets of remote labs based on a software package (called SINBAD) using Jini running on top of Java.50 The first one was for about 100 students with no experience in electronic measurements and who needed to learn about basic concepts. They undertook a range of remote labs. The students indicated satisfaction with the labs. The instructor commented on the additional time spent on the labs compared to those for traditional labs. The second set of labs was aimed at final-year students who needed to learn about in-depth control of programmable instruments. 25 students attended the normal labs and 25 undertook the remote labs, with the latter demonstrating greater learning results. This was ascribed to more time to design, implement and attempt their programs on the remote labs.
Digital Signal Processing Lab
A digital signal processing remote lab was constructed (at Texas Southern University and Prairie View A&M) based on Java and accessed through a web browser and URL address.51 The following experiments were conducted on it: FSK modem encoding and decoding, audio player/recorder system, AM communications system, FM synthesis for music tones, spectral analysis and Fast Fourier Transforms. In addition, a robotics remote lab was set up based on National Instruments NI ELVIS system, Quanser QNET motor board and a rotary inverted pendulum all using LabVIEW. The experiments proposed for the robotics lab included dc motor parameter identification, open and closed loop speed control, torque control, PID Controller design and stability analysis.
Java-based Digital Signal Processing Online Labs
Digital Signal Processing (DSP) labs have been engineered using an online DSP toolbox created at Arizona State University Department of Electrical Engineering.52 The complete DSP toolbox is accessible at http://jdsp.engineering.asu.edu/jdsp.html and would be ideal for distance learning courses. The software modules provide online 2D digital signal processing capabilities including signal generation, FIR filter design and transforms. Image processing functionality is also provided. Simulations are created by connecting selected blocks in the workspace. A number of specific lab exercises have been developed ranging from introduction to the toolbox, implementation of 2D linear and shift invariant systems, FIR design and 2D transforms. These were intended for use in the graduate Multidimensional Signal Processing and Image Processing course. Feedback from students has been generally strongly positive about the utility of the toolbox and learning value.
Supplementing of On-Site Labs
An approach to supplement existing on-site labs with a remote lab allowing experiments to be accessed 24/7 was undertaken at the University of Hartford College of Engineering, Technology, and Architecture.53 This lab system comprised four components: a web-based interface and database system, multiple lab station PCs running the test software connected to hardware/instrumentation and interfaced to devices under test. Each lab station had a pre-configured LabVIEW virtual instrument panel for the remote or local user to work with. An Agilent 4x8 multiplexer two wire switch was used by the remote user to access different test points on the devices under test.
Remote Lab in Circuits and Instrumentation
Michigan Technological University began offering its Circuits and Instrumentation course for non-electrical engineering majors to distance learning students.54 The challenge with the presentation of this course was the large lab component which was expensive and difficult to deliver and thus a change was made to convert it to a remote lab. This remote lab was based on using National Instruments LabVIEW and the Electronic Laboratory Virtual Instruments Suite (NIELVIS). This product not only provided the PC-based measurement tools but also provided a breadboard for building circuits. One disadvantage of these particular remote labs is the remote students' inability to make changes to the components and construct circuits.
Lab experiments offered over the 14-week semester included:
• Multimeter measurements on resistive circuits.
• Simulation of dc resistive circuits.
• Nodal Analysis.
• Thevenin Equivalent Circuits.
• Digital Oscilloscope Familiarity.
• Measurement of Transient Signals.
• ac Magnitude and Phase.
• Frequency Response to Passive filters.
• Introduction to LabVIEW.
When students logged into the remote lab website, they signed up to a time slot. The first familiarization remote lab introduced them to the fundamentals of current and voltage measurements by allowing them to adjust voltages of the power supply and the ranges of the multimeter. They were also familiarized with electronic components such as resistors, capacitors and inductances by viewing photos.
At the conclusion of the labs, a survey was done of two groups: the first cohort online working from a remote site (12 students) and the second cohort (nine students) doing the lab online whilst attending face-to-face lectures. There were 199 students in the regular class with cohort 2. It was found that the cohort 2 group were more positive about the labs measured in terms of "motivated to learn" based on a Keller instrument which measures relevance, attention, satisfaction and confidence. For the second cohort, their lab grade results as compared to the 199 students in the regular class were similar.
It should be noted that those involved in cohort 1 were working people whilst cohort 2 comprised students who were volunteers. Perhaps the difference is that the mature age working adults found the remote labs somewhat detached from their experience.
MIT's iLab with National Instrument's ELVIS
The iLab project at MIT was initiated in 1998 by Prof. Jesus del Alamo as a way of making his theoretical microelectronics lectures more practically oriented.55 The iLab project has since become an open set of remote labs (referred to as the iLab Shared Architecture released in 2004) and has been adopted by many universities throughout the world.
The iLab Shared Architecture (ISA) is a three-tiered architecture comprising lab client, a service broker and a lab server. Students log into the service broker (located on their campus) and then launch their iLab clients. The lab server is connected to the lab equipment and translates experiment specific requests into instrument specific commands and returns experimental data to the lab client. The iLab architecture uses web services for communication between the lab client, service broker and lab server. XML encoding is used between the lab client and server.
A complimentary low-cost approach is to supplement the iLab with the Educational Laboratory Virtual Instrumentation Suite (ELVIS) from National Instruments which provided a basic function generator, an arbitrary waveform generator, variable and fixed power supplies, digital and analog I/O and oscilloscope with LabVIEW for less than $3,000. A further new dimension to the lab was created, by adding in computer controlled switching, thus allowing for components to be added in or taken out of the circuit remotely. The resultant ELVIS iLab together with the Microelectronic's Device Characterization iLab and Dynamic Signal Analyzer iLab enabled students to perform dc, time domain and frequency domain measurements in MIT's introductory circuits and electronics course.
In 2008, the ELVIS iLab was packaged into a coherent offering, dubbed ESyst Analog Systems iLab, and made available more widely. In a partnership with MIT and three African universities (Obafemi Awolowo University in Nigeria, University of Dar-es-Salaam in Tanzania and Makerere University in Uganda), the ESyst was used widely and hosted on these campuses. There have been a number of lessons learned from these experiences.
These types of remote labs are appropriate for students who can create meaning from the fairly abstract. However, the typical audience mainly comprising part-time students, is one who would probably benefit from a less abstract experience. Hence it is important to make the lab as concrete as possible with videos and audio streaming. There was also a need for more instructor and resource support for these labs. Finally, one of the ongoing challenges in Africa has been the urgent need to improve retention of faculty trained in these technologies.
ELVIS v4.0 iLab
The ELVIS v4.0 iLab, now supports digital logic together with dc and component measurements through the digital multimeter.56 The Digital Multimeter module allows users to take a wide variety of simple point-to-point measurements. The user specifies the points in the circuit where the multimeter probes should be placed with the type of measurement (current or voltage). The lab server then drives the appropriate switches connecting to the circuit under test to produce the measurement.
Remote Robotic Lab
A useful lab based on the widely available Khepera robot helped provide skills in programming in this rapidly growing field.57 The Khepera robot being programmed is tiny with a diameter of 55mm and height of 30mm and affordable with prices quoted up to $2,000. Its motion is provided by two dc motors with encoders. It is programmed with GNU C. The stable and widely available open source software, Apache server, communicates to the robot wirelessly. A webcam provides a view of the activity of the robot.
Three methods of training for programming of robots were noted. These included the direct action level for an introductory course with basic instructions such as “advance” or “turn”. The second level is the configuration level where the program has built in parameters that can be altered. The third level–the operational level–is where the student applies advanced programming techniques either on a robot or its virtual simulated model. This may include such modules as error management that deal with such issues as deadlocks and preventing the system freezing, and in addition, provides feedback to the student. The simulation module (In VRML, or Virtual Reality Modeling Language) allows testing on the student’s program before being uploaded to the robot. Experiments in remote programming and operation of the robot were conducted from Lebanon to the computer server in France (which in turn was connected to the robot via a wireless link).
Mechatronics Remote Lab
A mechatronics remote lab (referred to as a Recolab or remote control lab) at the National Changhua University of Education, Taiwan with 12 experiments was set up based on sensors, actuator, PLC, conveyer belt and webcam.58 Different colored items were placed in a storage area. A pneumatic cylinder places one of these pieces on a conveyer belt at a time. When the item reaches the end of the conveyer belt, another pneumatic cylinder transfers it to the tooling area. In the tooling area, one cylinder selects the red item and another cylinder the black one. Some students who had initial difficulties with the experiment had to be reminded to read the lab instructions and experiment before commencing the experiment formally.
A comparison was made between a control and an experimental group of students who used the Recolab. It was found that the students who undertook this lab as an additional activity had significantly better grades. However, it would appear that this is not really a fair comparison as it is reasonably logical to expect that students who did additional focused work in the subject of interest would naturally do better.
Remote Lab and Take Home Kit
A comprehensive distance learning solution was provided with a series of remote labs for programming a mobile robot in C++ and a PLC controllable Profibus module.59 In addition, a mobile lab was provided to students where they could experiment from home. This remote lab provided a connection to the home computer using a USB connection.
Remote Lab using a Stepping Motor to Make Changes
A remote lab was built up comprising LabVIEW server, data acquisition board (referred to by National Instruments as ELVIS), passive electrical components and webcam.60 The resistors, inductors and capacitors are selected using a stepping motor. The motor driver runs the stepping motor based on control bits from the data acquisition board. There were some problems with excessive errors in the testing due to the range in tolerances (10%) of the electrical components.
A Remote Lab but With Remote Wiring
The Department of Electrical Engineering at the Blekinge Institute of Technology in Sweden set up a remote lab project in 1999 to duplicate the traditional hands-on lab workbench for electrical experiments (e.g. for electronic op. amp experimentation) referred to as a VISIR (Virtual Instrument Systems in Reality).61 This means that the labs could be used in a traditional supervised lab class; in a supervised lab for distance learning students or alternatively; when students want to work further on their traditional experiments at home.
The VISIR platform has four components to it:62
• An equipment server that comprises the lab equipment, PXI platform connected to the relay switching matrix. The last two are controlled by a LabVIEW server.
• A measurement server. This is a server written in Visual C++ and controls the commands passed to the equipment server with a file containing the maximum component values and instrument adjustments for a particular experiment.
• Web Server. This hosts the VISIR web interface and is based on an Apache Server with a MySQL database.
• Web Interface written in PHP with the experiment written in Flash.
The student accesses the website through the secure protocol “https”, gets authenticated and then designs her circuit. This is sent to the measurement server to be verified and thence to the equipment server to be converted into a wired circuit, which is then displayed to the student.
Although the VISIR has its own LMS, many other institutions are adapting this to their own LMS.
There are four types of accounts: administrator (for lab organizer), teacher account (for adding or removing experiments), student/instructor (linked to a specific course) and guest for a limited trial account.
Unlike most other remote control labs, this one offered the opportunity to perform remote wiring of circuits using a switching matrix with controllable electromechanical relays. All the instruments are PXI-based (PCI eXtensions for Instrumentation), being PC-controlled plug-in boards with a small front panel for connectors. Students remotely access a virtual breadboard (being a photograph of an ordinary physical solderless one) using a mouse to undertake the necessary connections. A software module (the Virtual Instructor) checks that every circuit is safe before it is activated so that neither a component nor instrument can be damaged. The required circuit and instrument set up are sent to the remote server when the Perform Experiment button is clicked. If the workbench is not occupied by another student, the experimental procedure is undertaken. Otherwise the request is queued. The current time slice is extremely short–around 0.1 seconds to perform an experiment.
This remote lab software is disseminated as open source software as part of the VISIR (Virtual Instrument Systems in Reality) Open Platform project.
Use of a Switching Matrix
A remote electronics lab was set up at Blekinge Institute of Technology in Sweden to be based around not only resistors, capacitors and inductors but also active components such as transistors and operational amplifiers.63
A controller and instruments was plugged into a National Instruments PXI chassis. The client software was an ActiveX control embedded in an html page that could be downloaded from the lab server. Netmeeting was used to communicate between instructor and students. A switching matrix controlled by the digital I/O board was used to connect different components. A virtual oscilloscope (based on the one from Agilent Technologies) was used to view the waveforms. A virtual breadboard was used by the students to wire up the different components. Students used a mouse to position each component on the breadboard and the virtual wiring to connect the components appropriately. Pattern recognition software matched the wiring on the breadboard with the matrix pattern and produced a component list to describe the circuit constructed. When the student was ready, the Perform Experiment icon was clicked and then the net list is checked for safety and then voltage is applied and measurements are taken. The server software was written in LabVIEW 7 and C++. The time period for any measurement was typically 0.1 seconds.
Virtual, Remote and Inter-Campus Labs
A combination of three types of labs–inter-campus, virtual and remote–were used by the University of Texas -Pan American and University of Texas at San Antonio, to demonstrate dynamic systems modeling and control concepts and thus to enhance the mechanical engineering courses at both of these universities:64 The goals of using three varied labs were to improve the visualization processes, increase the level of participation and collaboration between students in improved understanding of these complex concepts. The inter-campus approach involved students on the one campus developing a computer-based model using MATLAB and SIMULINK and the other campus’ students performing the actual experiments. The results were compared and roles swapped for the next experiment. The remote lab was accessed by individual students through a web page using LabVIEW’s remote panels software. A MATLAB / SIMULINK-based simulation was set up and a 3D animation was created using MSC VisualNastran 4D. Finally, a virtual lab was developed using MSC VisualNastran 4D and accessed over the internet. The virtual system provided both an animation of the simulated equipment, time and frequency domain graphs. In a post-lab survey, almost 80% of the students believed that the virtual system animations had improved their ability to visualize the physical responses of the equipment.
Remote Lab for FPGA-Based Reconfigurable Systems Testing
A low-cost remote lab was developed at the Department of Electronics and Multimedia Communications at the Technical University of Kosice, using a FPGA / PC Connected test hardware and PC controlled logic analyzer, digital storage oscilloscope and vector Signal Generator.65 Alternatively, all the standalone instruments could be replaced with a data acquisition board and National Instruments' LabVIEW. One challenge with the remote lab was the lack of precise parallel triggering using both Ethernet and USB buses.
Mechanically Challenging Microelectronics Lab
Arguably, the mechanical challenges at the microelectronics level are considerably more challenging than those for the electronic ones.66 This is best illustrated by the conversion of a traditional microelectronics lab to a remote lab. Microelectronic fabrication labs are expensive and teaching in this area is influenced by the availability of these resources. Besides the usual advantages of sharing expensive equipment, remote microelectronic labs have the additional advantage of reducing the risk of contamination by people entering the facility and keeping inexperienced students away from dangerous chemicals used in the fabrication process.
The School of Electrical and Information Engineering at the University of South Australia owns a lab for microelectronic circuit fabrication and has converted this to use as a remote lab as well. It was also noted that this lab has an advantage over other labs using packaged integrated circuits in that they test their circuits directly on the silicon wafer. This ensures the system is independent of the circuit design and does not require any pre-wiring. The disadvantage is that the mechanical motorized probes have to be accurate to access any point in the view of the microscope.
The remote engineering lab included:
• A test station allowing for a digital interface.
• Modified probes that could be digitally manipulated.
• Microscope and camera with remote control of zoom and focus.
• A camera that can coherently view the device-under-test.
• Remotely controlled lighting.
• A PXI unit that allowed for measuring the characteristics of the device under test as well as a matrix switch unit to connect the PXI unit to the appropriate probes.
• LabVIEW server providing the graphical interface for monitoring and control.
• A database containing all user details.
• A web server to interface the user to the database.
The main challenges with this remote lab were in achieving the accuracy of probe manipulations to a 10 micrometer step size using a screw-bolt combination (with a rotation step size of 4.5 degrees). The backlash for the thread was reduced by using a spring to push the screw so as the contact between the nut and bolt is kept to one side. The contamination sources were from the brushes in the control motors and thus brushless dc motors were selected for all mechanical movements. Other problems with brushes, which were also thus eliminated, were sparking and wear and tear.
Overall, the students were happy with the remote lab especially in being able to access (and to repeat) the lab at their own time and location.
Comparison between Direct Execution and Remote Desktop
A remote lab for FPGA (Field Programmable Gate Array) was set up with seven stages of which the design procedure encompassed stages 1 to 5 using Electronic Design Automation Software and Stages 6 and 7 requiring access to the actual FPGA hardware.67 A lab manager program was located at the remote lab and operated as a server and executed the experiments. The client application accessed the remote lab through a VPN tunnel.
Two alternative methods of access to the remote lab were in using direct execution or remote desktop. The first approach was in using a direct execution method that required the student to write the program on her home PC and then to upload the file to the remote lab manager (at the remote lab) and download this binary file to the FPGA kit. The second approach was to use the Microsoft Windows remote desktop method where the student did all the programming activity using the Remote Desktop software and then downloaded the file to the FPGA kit.
In comparison to the Remote Desktop method, the direct execution approach was found to be faster, allowing for more than one user access (compared to only one for remote desktop), to have a higher level of security and to use a lower level of resources (including bandwidth).
Movement from Remote Labs to a More Individualized Model
It was suggested that due to the increasing use of cloud computing, inexpensive labs can be located with each learner (as opposed to a centralized remote lab), but can also be accessed by the instructor and other students.68
A proposed [email protected] was demonstrated comprising the cloud and the distributed personalized user lab areas. The open source software used (virtually in the cloud) was called BigBlueButton allowing for application sharing, whiteboard, private or public chat rooms, audio and videoconferencing and uploading and presenting documents. Dropbox software provided storing and sharing files between the different students as well as the instructor–all located remotely from each other (with file versioning to minimize confusion).
This system was applied to an experiment performing the calculation of the transfer function for a second order circuit in a Basic Linear Control systems course. Each of the two sites used a different kit: The first site had a Digilent Electronics Explorer kit including oscilloscope, waveform generator, power supply, voltmeter, breadboard and reference voltage generator where digital signals could be configured with a pattern generator and a logic analyzer. The other site used a CircuitGear kit including similar facilities. All data generated were stored by all participants.
Popular LabVIEW has a few Challenges
One of the most popular software packages used for labs is LabVIEW as it is quick and easy to configure and has varied data acquisition and control boards to interface to.69 The runtime engine (which runs on the remote computer) does have a few problems as it requires administrator privileges and this restricts its flexibility on operating on any computer. Updates to LabVIEW on the lab equipment computer can cause incompatibility problems on the client computers. National Instruments have introduced a solution using RESTful web services (Representational State Transfer) which provides a lightweight protocol accessible by a variety of clients but there are still some challenges here with multiple experiments and multiple users with multiple resources.
An experiment was set up at the University of Houston based around the Carbon Nanofiber Beam Experiment. This used carbon nanocomposite paper with ferromagnetic properties (due to nickel particles) coated with a clear silicone gel. This piece of paper was located between two coils that generated a magnetic field and thus displaced the paper depending on the current strength in each coil. The displacement was measured with a laser displacement sensor.
A number of technologies were employed to ensure only a browser was required to view the remote experiment (running using LabVIEW) without any software downloaded to the client.
The client interfaced to the Web Server using Web Services Gateway Interface (WSGI) rather than the slower Common Gateway Interface (CGI). REST provided a means of the server handling data from the client using GET, POST (particularly this method requesting an update to the experimental data), PUT and DELETE.
The experiment was set up using LabVIEW, which parsed the relevant data from the experiment into an array that was dispatched through a TCP socket to the MySQL database on the web server. A webcam view of the experiment was also dispatched to the web server.
Mobile Studio IOBoardTM
Morgan State University used the Mobile Studio IOBoardTM (from Rensselaer Polytechnic Institute) to redesign their lab courses for two courses: Electric Circuits and Introduction to Electrical Laboratory to make them totally online.71 The Mobile Studio IOBoardTM provides a comprehensive online electrical circuits lab which the students can work on at home. The Panopto Focus software was used to record a synchronized version of the text, audio and video from the daily lectures; thus allowing students to watch the streamed versions of the classes. Adobe Connect web and videoconferencing software was used for the students to demonstrate their labs and projects to their instructors at an agreed time without being physically present on the campus.
One of the major challenges was the difficulty for students in completing the labs on their own due to their lack of familiarity with the Mobile Studio IOBoardsTM. The online students had less time in which to undertake their course resulting in fewer labs undertaken and lower grades (as compared to the regular courses).
FPGA-Based Remote Labs
At the Abafemi Awolowo University in Nigeria, there was a significant shortage of digital electronics labs; particularly for Field Programmable Gate Arrays (FPGAs) as for the Altera DE1 board; and a remote lab was constructed for this using the MIT iLab batched architecture.72 The iLab architecture allowed for three different types of experiments:
• Batched experiments where the experiment is totally specified before it commences.
• Interactive experiments where there is ongoing (hopefully) real-time interaction as the experiment progresses.
• Sensor experiments where the experiment is only observed with no control taking place.
The ADLab was developed using the batched approach with three components:
• The lab client running within the web browser.
• The Service broker providing authentication, authorization and administrative functionality (to the lab client) and storing the results of the experiment.
• The Lab server executing the experiment.
Figure 10.3: Batch Architecture Based around MIT iLabs
One challenge in viewing the experiment (such as the LEDs and other input/output options) was the relatively low bandwidth at the university for streaming (64kbps for each video stream to each client). A video streaming service such as MOGULUS was thus used and the script embedded into the client.
The students could create a VDHL listing and thus synthesize digital circuits on the FPGA. All signals and measurements are carried out through a NI data acquisition card. Two types of results are available: a webcam view of the output of the LEDs from the board and a detailed VHDL analysis and synthesis report together with measurements of the FPGA pins.
There were mixed reviews to the lab from a small sample of students.
Microelectronic Lab in Montpellier
The test resource center (CRTC) of the National Committee in Microelectronic Teaching (CNFM) located in Montpellier, France brought together different French universities and research institutions in the study of microelectronic technology.73 A new test system based on the Verigy pin scale test platform was shared between the different universities in Europe with remote access. The instructor and equipment were physically located in Montpellier but the classroom was located remotely using VNC to access the system. Voice over IP was used to communicate. The instructor could follow the progress of the students and help them remotely.
Boiler Control System Remote Lab
A remote lab was constructed from a small boiler control system with water level and temperature being the controlled variables.74 Three communication standards were used to interface to the instruments, control gear and SCADA system: DeviceNet, Profibus DP and Modbus/TCP Industrial Ethernet. A webcam connected directly on the internet with Pan/Tilt/Zoom was used for remote monitoring.
Figure 10.4: Boiler Control System Remote Lab
The major problems encountered were difficulty accessing the campus network (on which the remote lab was situated), difficulty in accessing the SCADA node through certain ports that could only be opened at the server and firewall problems. Finally, the transmission delays (up to 15 seconds for the SCADA node) from external sites in other countries made the lab difficult to operate. It was also considered vital that only one user at any one time could manage the control and instrumentation to ensure a coherent experience.
Remote Workbenches for 80C51-based Courses
The Faculty of Engineering at the University of Porto, Portugal put together an 80C51 lab with three components: A Moodle LMS hosting the learning resources, the lab server and the workbench comprising a National Instruments ELVIS workstation and general purpose 80C51 microcontroller board.75 The ELVIS platform had all the required instruments as well as digital inputs/outputs to control the microcontroller board (reset CPU, emulate input keys/local switches). A webcam provided live feedback of the seven LEDs emulating the seven dots of an electronic dice. The students commenced their work offline using a simulator to validate their code. This was then uploaded to the remote hardware lab and tested collaboratively using the video stream of the hardware, text chat and videoconferencing room. The University of South Australia set up a similar remote lab using a different microcontroller and with keyboard and LCD display for more complex programming tasks. Interaction with the hardware occurs via a virtual keyboard and virtual button.
A few conclusions from this research were:
• The remote workbench does not have to be the same as the real face-to-face lab environment but should exploit the flexibility in the remote lab environment.
• Synergies between the simulation (virtual lab) and remote lab environment should be leveraged to give greater educational advantages.
• Although remote labs can provide a deluge of GUI, video and audio information for the average experimenter, care should be taken to avoid irritating disabled students who may not be able to access these additional streams of information.
Proposed Remote Telecommunications Lab
It was proposed that a remote telecommunications lab where students could log in, generate their own AM/FM/BPSK signals, set up a bandwidth limited signal and do a spectrum analysis using a (RF) switch matrix for control of the hardware switching sequences.76 The remote lab was to be built around a National Instruments ELVIS (with LabVIEW and data acquisition board) together with a telecommunications training board (DATEx) from Emona Instruments and a RF switch matrix.
Microelectronics Remote Lab
A series of microelectronics remote labs were built by the University of Bordeaux, France covering such topics as RC and RLC circuits, feedback and differential amplifiers, and linear op amps.77 A set of Cyberchips was designed based on BiCMOS technology with up to 75 different measurement configurations. A switching matrix was constructed to switch the various electronic circuits. Third-year engineering undergraduate students have been using it every year (since 2002) for experiments such as measurement of MOS capacitance, differential pair amplifier and feedback amplifier experiments. These experiments have been used live during lectures thus giving more realism. When clicking on the experiment, a pop-up window is created that provides a simplified interface to set start and stop frequency values, dc bias and input voltage signal level. After clicking on “Go”, the results of the measurements are shown, and then these can then be saved in a spreadsheet for further analysis.
A Machine Vision Lab
A machine vision course was created at the University of Georgia, Biological and Agricultural Engineering Department.78 The lab component was considered a major component of the course but access to the scarce lab resources was only available during normal working hours. Hence, a remote lab was set up with two PC-based machine vision workstations and a web/FTP server PC; using VNC for remote sharing and Microsoft’s Netmeeting for video and audio. The associated lab equipment comprised frame grabbers, data acquisition and a motion control card and a spectrometer. The VNC software was used for remote administration of the machines.
The process is for the student to log onto the lab website where an Active-X control will activate the NetMeeting software on the student’s machine to call the remote lab. The student is provided with the X, Y positions to be used to move each test sample to the appropriate position. The entire system is reset to the OFF state after a time period of 20 minutes elapses without any activity. Incredibly, a 56K modem connection was used to conduct the experiment.
The 15 students enrolled (in 2002) indicated satisfaction with the course, although there were some problems with sluggish workstations requiring regular restarts of computers (and remotely via VNC on weekends).
A High Voltage Remote Lab
A remote lab was built around a traditional high voltage lab (commissioned in 2009) at the National Institute of Technology, Durgapur, India.79 This was used for impulse voltage testing and evaluation of results; thus supporting theoretical grasp of the topic. The setup of a fully equipped high voltage lab can be extraordinarily expensive and the remote access can widen the participation to a far wider community.
The lab comprised an 800kV, 40kJ Marx generator, a 100 kV rated rectifier, an 800kV rated divider and the test sample (a typical example being a 33kV insulator). A Windows-based server, data acquisition card, automation module and digital storage oscilloscope coupled with webcam and Data Acquisition / SCADA package completed the system.
A typical lab comprised a 33kV rated post insulator and impulse voltages ranging from 82.3kV to 273.4 kV were observed. This remote lab was one of the first of its type in the world for high voltage engineering.
Remote and Virtual Labs for Robotics and Machine Vision
A combination virtual and remote lab was set up at the University of Alicante for robotics and machine vision.80 The ROBOLAB-2 software program was developed around Sun’s Java3D API to simulate the operation of a real robot and to teleoperate a remote (a Scorbot ER-IX) robotic arm. Once the student has successfully executed the simulation, she can then request the web server to execute movement sequences with the real robotic arm. Verification of the correct movement is through a video stream showing the execution of the movement sequence. Alternatively, the simulation software replicates the movement based on feedback from the real robotic arm’s joints.
The essentials of machine vision are learned through the VISUAL package allowing students to specify a combination of algorithms using a graphical method of combining the individual modules (referred to as Objects for Image Processing or OPI). The inputs of an OPI are the original images and the output is the processed image. New OPIs can be written and added to the existing suite of modules for VISUAL.
Overall, 80% of the students indicated satisfaction with ROBOLAB and VISUAL. One feature being worked on is to provide real time virtual collaboration with other students and remote instructing support.
An Image Processing Remote Lab
A remote image processing lab was created to allow students at the Carinthia University of Applied Sciences to experiment with zooming and focusing of images.81 The key part of the lab exercise was for the students to develop an auto focus algorithm. This algorithm was written within the LabVIEW development environment (using the Vision Development Module libraries for image processing and analysis).
The visual presenter used a third progressive scan CCD to acquire the image and an analog RGB-output to communicate with the PC. A RS-232 port was used to control the main functions such as zoom, focus and to switch through different lighting arrangements. A NI image processing card on the computer digitized the images.
The visual presenter could be controlled remotely using LabVIEW in conjunction with the iLab remote lab architecture.
The front panel (with buttons) is created within LabVIEW and is then published to the web for others to access the lab remotely. The student can then control the different actions of the lab. By simply pushing the appropriate button on the front panel, the code written by the student will be executed and the results can be observed within the web browser. A Stop Autofocus button was implemented for when the algorithm is working incorrectly and needs to be terminated.
NI ELVIS with Engineering Labs
A remote lab was constructed with two NI ELVIS devices connected to a PC on which the LabVIEW application software ran and which also acted as the main server for remote access to the experiments.82 The popular instruments are all available in software: digital multimeter, function generator, oscilloscope and spectrum analyzer. A webcam was also placed at a high vantage point so that the experiment could be viewed. Five experiments were set up comprising measuring dc motor parameters, PID control of dc motor, temperature measurements (light bulb heating up temperature sensor), light source and phototransistor (examining the distance from the light source and phototransistors output) and a traffic light system.
Remote Lab using Stepper Motors to Control Circuit Parameters
The lab was constructed using LabVIEW providing remote access to an experiment comparing theoretical to experimental values for a range of resistor/inductor/capacitance values.83 The NI ELVIS data acquisition system was used together with a CCD camera. The data acquisition board sent the necessary control signal (8-bit) to one of twenty-one motors (using a further 5-bit control signal). In addition, the data acquisition board had a digital multimeter for reading the required voltage signal. The various circuit configurations are built around nine resistors (10 Ω to 10 kΩ), an inductor (0 mH to 99mH) and a capacitor (100pF to 999nF).
A graphical user interface comprised the following sections:
• A view of the experiment with the camera.
• A graphic of the circuit being constructed.
• Circuit construction section.
• Data display section.
One disadvantage with this approach was the large error encountered in the comparison between theoretical and experimental values (up to 35% in the one case). This issue was being addressed in the next iteration of the lab.
Remote Labs at Florida Atlantic University
Two remote labs constructed at Florida Atlantic University included an active element transistor characterization experiment based around a microcontroller/data acquisition and web server chip.84 The student adjusted the transistor’s base current and applied a voltage sweep function on the collector. The voltages/currents were then read by the microcontroller and saved in an Excel spreadsheet for later review.
A second lab was to determine static and kinetic friction of a block on a changeable inclination plane (controlled by a stepper motor). The angle of the incline was measured by a remote camera and protractor. A second stepper motor was attached to the block via a thread with a force sensor. The static friction coefficient was calculated by increasing the angle of the plane until the block slid down. The kinetic friction coefficient was calculated by pulling the block up the plane at a constant speed.
Remote Labs based on CAN Bus
CAN is a well known serial data communications protocol for industrial applications and was successfully used at Suleyman Demirel University in Turkey for a series of remote labs.85 Two experiments on CAN Bus nodes for measurement of diode and transistor characteristics, were connected via CAN BUS to a server computer (using a PCI card). Each experimental node had a microcontroller providing analog output values for the experiment and analog inputs to measure the outputs from the experiment. LabVIEW on the server published the CAN-based interface allowing for easy access by remote users on the internet. The user interface comprised three sections: configuration, send data and receive data from the experiment. Up to 112 CAN nodes were possible.
Remote Labs based around a FPGA
At the University of Patras in Greece, Department of Electrical and Computer Engineering, a series of remote labs (referred to as RMCLab or Remote Monitored and Controlled Laboratory) were implemented based on the usual client-server architecture.86 This comprised student client, instructor client, application server and resource server. All clients are required to interface to the resource server (connected to the lab equipment) through the application server. This approach enables many application servers to access components shared by the resource servers.
The resource server is connected to an oscilloscope (through GPIB interface) and the function generator (through RS-232). The resource server is also connected through a low-cost printer bus to an Altera FPGA and associated components for the online implementation of the experimental circuits required for a particular session.
The RMCLab supported classes of 300 students in two core courses: Analog and Digital Electronics. Analog experiments included two-stage feedback amplifiers, cascade / folded-cascade amplifiers, whilst digital experiments focused on counters, adders and accumulators. Students were grouped in teams of three or four to undertake the experiments. In the 2004/5 period, the remote labs were used extensively by 74 active teams working over 383 hours with approximately 3 hours per experiment.
Remote Lab for Frequency Modulation Experiments
The aim of the experiment was to examine the frequency spectra of frequency modulated signals at the National University of Singapore (NUS).87 The lab equipment comprised a spectrum analyzer, a signal generator, a frequency counter, a voltmeter and a circuit board. The rationale of the remote lab was to provide a hands-on experiment for the few hundred students who previously had been deprived of working with this expensive equipment in a dedicated fashion. The various points of the circuit had to be connected together remotely with leads, thus giving a hands-on approach.
A PC with an Ethernet card connecting to the NUS network was the main lab controller device with GPIB and a data acquisition card. This used LabVIEW software to provide the necessary control and data acquisition. A Java Applet embedded in HTML files was downloaded onto the student client computer. A web browser supporting Java was all that was necessary for undertaking the experiments. The student client then interfaced to the Web Server using TCP sockets. The web server then acted as a client to the Lab Controller computer (thus creating a double client-server structure). This architecture was created for security reasons.
Remote Lab for Control of a Helicopter
The control plant comprised a 2-degrees of freedom helicopter consisting of a model mounted on a fixed base with two propellers driven by dc motors at the two ends of the rectangular frame.88 The coupling between the pitch and yaw motor torques resulted in a coupled 2-input / 2-output system. The electrical signals to the helicopter motors were fed through slip rings. This configuration allowed for four different controller interfaces to be investigated: PID Control, decoupled PID Control, general state space control and fuzzy logic control.
The architecture comprised a student client computer connected to a web-server over the internet. This was then connected to the local instrument controller PC that connected to the helicopter rig though a data acquisition card thus providing the analog output voltages to the two dc motors. In addition, to provide a stronger feeling of reality, an additional PC has Microsoft Netmeeting providing video and audio feedback to the student.
This lab was available 24/7 and was used as a component of the homework assignments providing considerable flexibility for part-time students from industry who were unable to access any experiments after hours due to the security concerns.
Telecommunications Remote Labs
A set of remote labs was created at the University of Transylvania in Romania based around experiments on Analog Modulation (Amplitude Modulation, Frequency Modulation and Double Sideb and Modulation), Digital Modulation (Amplitude Shift Keying and Frequency Shift Keying) as well as Pulse Modulation (Pulse Amplitude Modulation, Pulse Position Modulation and Pulse Width Modulation).89
An Emona DATEx module was interconnected with an Agilent switch (8x4 matrix) and PC running LabVIEW for undertaking the abovementioned labs. The Emona DATEx is connected with the NI ELVIS platform and LabVIEW with all buttons and switches of the Emona hardware remotely controlled through LabVIEW. The other choice is to operate in local manual mode where the switches and buttons are adjusted by hand. The Emona DATEx module comprises such working blocks as an Adder, Function Generator, master Signal and Multiplier.
As there is a huge amount of information to present to the student, a normal lab structure is broken up into six windows:
• Objectives: Goal of the lab.
• Introduction: General aspects of modulation.
• Math part: A description of signal wave shapes and their mathematical parts.
• Questions: A short quiz that the student has to undertake before commencing the lab.
• Instruments used: A description of the equipment used.
• Lab Description: A description of how to apply the equipment in the lab.
Five Remote Labs
Five remote labs covering coupled tank, oscilloscope, frequency modulation, helicopter control and robotic soccer were created at the National University of Singapore.90 Discussions on the labs have been canvassed elsewhere but here is a quick summary of the key elements.
The oscilloscope has a high level of realism with real-time video capture of an actual oscilloscope display provided on the user interface. In the coupled tank experiment, LabVIEW is used together with Microsoft Netmeeting and a camera and microphone to provide visual (and audio) feedback of the actual movement of water in the tanks. The camera had remote controllable pan, tilt and zoom.
The first lab was launched in 1999 for over 1,000 engineering students in the NUS and has been used for over 2500 unique experiments. The coupled tank experiment has been used 5,000 times whilst the frequency modulation one has been run 4,000 times. The ease of only having to use a Java-enabled web browser makes the whole process seamless for the student.
Microcontroller-based Remote Lab
The rather critical comment is made that most new remote labs are not as professional as they should be.91 This assertion is backed up by the fact that very few universities have adopted other university’s remote lab technologies and there is no evidence of commercial development of remote labs (apart from possibly National Instruments). It was further pointed out that in the research and development on remote labs, crucial hardware aspects such as frequency and accuracy are neglected in favor of issues related to actually establishing the remote lab infrastructure (security/cross platform etc.) rather than the real lab equipment. The hardware and software components are normally inextricably tied together thus making it difficult to move a remote lab to another LMS platform without making major changes. The software is generally not user-friendly for instructors (e.g. to install or configure).
At the University of Deusto a simple microcontroller-based weblab was built to address these concerns. This was based around a PIC18F97J60 microcontroller for the student to build the project. It could be programmed through the USB ports of the server. In addition, there was an output board comprising two alphanumeric LCDs, 8 LEDs, two seven-segment displays and a servo (allowing PWM experimentation). An input board based on a PIC18F97J60 received from an interactive web page instructions to set/reset digital and analog inputs and data through the UART port. A webcam (with motorized pan/tilt controls) monitored the output board activity. Finally, an Intel Atom-based computer acted as the server. The student created a binary file in her preferred development environment, and then connected to the remote lab, sent the relevant file to the experimental PIC microcontroller using the TFTP protocol. After the PIC was programmed, the interactive web page was automatically opened allowing the user to test the operation of the program. After 60 seconds, the student was then passed to the end of the queue of users.
This structure allowed for a remote lab to achieve three characteristics: a reliable, professional and stable item of kit, adaptable to different types of educational requirements and finally, extensible to different labs without too much modification.
European Remote Radio Laboratory Based in Turkey
A remote lab has been constructed at Atilim University with three hardware modules comprising:
• A Vector Network Analyzer.
• A waveform generator/spectrum analyzer and oscilloscope (for time and spectral domain signal analysis).
• A non-linear amplifier, combiner, signal generator, attenuator and spectrum analyzer (for intermodulation distortion measurement).92
12 experiments were constructed from various combinations (using switches to make dynamic connections for a particular experiment) of these hardware components ranging from measurement of scattering parameters, spectrum analysis to radio frequency amplifier measurements and analysis of antennas.
The main components of the remote lab comprised:
• A Learning Management System (Moodle) to provide authentication and access rights for students as well as the usual facilities such as assignments, exercises and course details.
• An Electronic Performance Support System providing access to assistance in performing the experiments.
• PCs connected to data acquisition boards and the web server providing access to each experiment.
• Experimental equipment.
• Database Management System for storage of all experimental data.
The labs have been focused on three groups: students, engineers and technicians.
A concluding comment from the authors is that they would invest more effort in improving the graphical user interface as well as adding in some basic electronics subjects.
VHDL Programming Course
This course was offered to third-year students undertaking the Electronics and Control Engineering degree.93 The course was based around the VHDL-VHSIC hardware description language for field-programmable gate arrays and integrated circuits, and complex programmable logic devices. The University of Deusto has set up an open source remote lab based on AJAX and web services.
The student wrote the VHDL code, performed a simulation on it to confirm it worked and then downloaded a binary file to the remote lab. Externally, the remote lab board has 10 switches, 4 buttons, 1 clock, 6 LEDs and 4 seven segments. The design is tested by viewing the results through a webcam. When the program is running correctly, the result is recorded on video. The final program and video was then uploaded to the Moodle LMS.
Remote Labs Demonstrating First and Second Order Response Control Systems Two remote labs were built at the Universities of Jordan and Philadelphia using LabVIEW, associated data acquisition card and NI Elvis software with a USB-based camera.94 The first remote lab was a simple RC (100kΩ resistor and 1 µF capacitor) electrical network showing the first order response as well as phase shift and attenuation. The second lab was innovative and was based on a compound pendulum with a motor-propeller fixed to one end that provided a thrust force to control the angle of the pendulum. A shaft encoder was used to provide angular feedback. Thus, open and closed loop responses could be demonstrated and optimal tuning of the PID Controller could be tested.
Electronic Performance Support System for European Remote Radio Laboratory
It is challenging to pre-suppose the precise learning path a learner will follow in proceeding through an experiment.95 An electronic performance support system (EPSS) is a good solution for helping a learner grasp the essentials of what is required especially for those who want to study in a non-linear way. This provides immediate personalized guidance to any queries that may arise during the experiment. An EPSS was set up for a remote lab for Vector Network Analysis equipment. The learner merely clicks on a link and is provided with more detail. Alternatively, use of a search facility provides access to documents, videos, audio and support software.
A Remote Testing Project
In 2008/9, software engineering students at the University of Wisconsin-Platteville developed a tool allowing for remote testing of real-time embedded systems.96 This allows for testing to be performed from the home site resulting in significant savings in terms of travel and labor. This formed part of a large project that the entire class worked on over two semesters for a local software house. The test tool was broken down into three components: an administrative website, hardware server (connected to the actual test equipment) and testing client (which access the hardware server). The embedded system comprised a PIC 16F877A microcontroller. A National Instruments data acquisition board with Analog and digital I/O was used as the controller of the test microcontroller and worked in conjunction with a Microchip MPLAB programmer/debugger. Both were connected to the hardware server through the USB ports. A webcam completed the testing equipment. Overall, despite initial poor definition of the initial requirements, the project was completed successfully.
10.5 Mechanical and Manufacturing Engineering
Industry Collaboration with an Internationally-based Remote HVAC Lab Project
A novel approach to remote labs involved developing an improved Heating Ventilating, Airconditioning (HVAC) product for a company (MicroMetl Corporation) by collaborative work between the mechanical engineering department of Purdue University and the HVAC Engineering School in Lucerne, Switzerland.97 The language differences (German in Switzerl and vs. English in the USA) were ameliorated somewhat by focusing the collaboration on the remote labs. Most controls in modern HVAC systems located in modern commercial buildings are web-based (and thus easily fit into the remote lab schema). Initially, the sophisticated HVAC labs at HTA Lucerne were used in the preliminary investigations. Students initially collected data on heat recovery effectiveness at varying air flow rates and using the seasonal weather data in a given location, were able to calculate the economic payback in installing heat recovery technology. A new project was started on integrating the MicroMetl heat recovery equipment with the Carrier air handling equipment. The Purdue students project managed the HVAC equipment (including sensors and a web-based HVAC control platform) installation and commissioning at their university in the USA. The Swiss contingent then had to assess the effectiveness of this new equipment. The ability to conduct energy efficiency tests remotely using the web-based interface was a key to the success of the collaboration, as there were delays in commissioning the Purdue University equipment. A useful approach was the blog site used to communicate each team’s efforts. The international standards used were also a benefit in making the students’ understanding and design more internationally-based.
Microelectromechanical System (MEMS) Laboratory
During a Materials Science course, students cover the electrical and thermal properties of materials. An experiment at Texas Christian University was devised to determine, “the in-plane tip deflection vs. power characteristics of a MEMS electrothermal actuator”.98 Many items of sophisticated equipment were used in this lab such as a microprobe station, microprobes, a microscope, video camera, VCR and TV monitor, a National Instruments (NI) data acquisition and image processing board together with associated software. The remote lab can be accessed by any computer with a web browser and the free LabVIEW run-time engine installed. Access limiting is applied so that only one user can access (and view) the experiment at a time for a limited time.
There were some difficulties in running the NI software on a MacIntosh operating system and it was not possible to visually determine the displacement of the MEMS device when power was supplied to it (against when it was in the rest position and unpowered). The remote experiments were done in 2007 and 2008, with the students working in small teams of three per lab session and in three lab sessions per year. It was noted that the student’s interest was immediately piqued when they realized they were working on a real system rather than a simulation. The success of this project is considered a great catalyst for developing similar labs in the future.
Jet Thrust Laboratory
Rutgers University and the University of Illinois at Urbana-Champaign developed a joint jet thrust laboratory for both to use.99 Some of the proposed advantages of this collaboration in building remote labs included:
• Reduced per institution costs and space requirements.
• Sharing each institution’s expertise.
• Ability of experiments to be customized to each institution.
• Supplementation of remote labs with multimedia pre-labs and detailed lab explanations.
• 24/7 access to anytime, anywhere labs.
• Safer labs.
• Lab demonstrations run for K-12 school students and general public.
A useful set of requirements for experiments was drawn up:
• The labs must have a high visual and graphical content so that they are clearly not simulations.
• A web browser is all that is required; no installation of specialized software is required.
• The experiments must be sufficiently complex so that an equivalent simulation is essentially impossible.
• The lab must provide everything from pre-lab, remote access and a post-lab with minimal instructor support required.
There were three basic components to the lab:
• A gatekeeper server allowing student access to the experiment, pre- and post-lab materials and storage of experimental data.
• The experimental apparatus comprising an air control system, the jet, traversing pitot probe system, direct thrust measurement and the Schlieren system (for observation of shock patterns).
• The experimental server using VNC software allowing for viewing of the remote desktop anywhere, LabVIEW data acquisition and control software, Filemaker database program providing step-by-step lab instructions and controlling access, and a camera streaming video server for showing the Schlieren images of the jet shock waves.
The learning outcomes were assessed by comparing the grades of the laboratory reports of students of the remote labs with those from the standard classroom labs. No statistical differences were observed. The students who undertook the one-hour multimedia pre-lab supervised sessions scored a significant 12% higher than those who performed the remote lab experiments immediately. Possible solutions were to ensure students perform an online quiz or undertake sufficient preparation time in the pre-lab materials before commencing the labs.
Rapid Prototyping and Collaboration
The term rapid prototyping (RP) refers to the construction of physical objects using 3D models and other associated fabrication technologies. A course on rapid prototyping was offered by the College of Engineering of Tennessee Tech University (TTU) as part of the Manufacturing and Industrial Technology major using the Desire2Learn (D2L) online course management software system.100 The lab component was restructured from a classroom-based one to a fully online one. The students used the D2L software to access the online course materials, participate in team discussions (presumably asynchronously) and were able to prototype their parts through the remotely accessible rapid prototyping lab. A campus student assistant helped facilitate the labs. The course had two major components comprising CAD and Rapid Prototyping. Lab practices have been organized using the schedule tool available with network cameras and audio to enable effective communications between the geographically disparate teams. Each team comprised three to five students. A trebuchet (essentially a catapult) was rapidly prototyped as an initial example of the lab. The engineering design instructor sent three pictures and details of the trebuchet to the teams. The teams then modeled the trebuchet using Pro/Engineering Wildfire 2 software and prototyped the product using the remotely accessible Rapid Prototyping lab. There were a few problems that the teams had to work through in the rapid prototyping lab such as initially omitting to create a throwing pin (linking the stand to the throwing arm) and then subsequently creating a pin that broke. They worked through these issues to a successful conclusion.
The post course survey indicated that the students were relatively satisfied (the term used most frequently was “somewhat agree”) with the team project and associated lab.
Mechatronics / Process Control Remote Laboratory (MPCRL)
In 2000, the Department of Mechanical Engineering at Polytechnic University in Brooklyn, USA created a series of remote labs which covered a wide array of topics ranging from aerospace, mechanical, electrical, civil and chemical engineering.101 These labs were structured to help students access labs beyond the traditional three hours per week and targeted both undergraduate, graduate and high school students with a reported seventy odd individuals using the labs in their initial release. The MPCRL comprised a website connecting students to the online experiments, detailed specifications and operations manuals of each experiment, videos of a few of the experiments, live streaming videos of each experiment (presumably while a student was engaged with it), a chat window to interact with other students, email addresses of all teaching staff and miscellaneous links to related websites. A wide range of sensors (e.g. potentiometer, tachogenerator, float level, flow rates, pH probe, pressure) and actuators (e.g. servomotor, servo valve, cone speaker, heat exchanger) were used.
Consideration had also been given to safety, based around hardware and software approaches being designed into the system. Hardware safety encompassed devices that restricted the range of operation for the equipment. This included the use of drainage pipes to remove overflow, limit switches and passive damping elements. Software safety limits were built into the Simulink software package by using saturation blocks and signal filters.
A queuing system was built into the lab allowing only one person to work at a time, for up to 10 minutes. Other users can observe the experiment.
A student survey gave some positive comments such as connecting theoretical knowledge to the real world and hands-on and troubleshooting interactions being considered particularly useful. The criticisms were that the labs should be run in tandem with the associated class and the fixed control architecture in the labs was considered restrictive.
Weblabs with ReLOAD (Real Labs Operated at Distance)
The application of remote labs aimed at a culturally diverse student cohort (such as females and ethnic minorities) was undertaken by the University of Leeds and University College London.102 This was for a series of mechanical engineering courses in vibration and control investigating how various parameters such as input frequency and input amplitude affected the performance of a position servo mechanism (for third year applied mechanics and automatic control and a postgraduate delivered module). The actual lab was based in the foyer of the Mechanical Engineering Department at the University of Leeds. The students submitted their parameters to a web page and then at the conclusion of the experiment received three individual graphs with an embedded video clip of the experiment. The web lab was used as tool to reinforce the learning rather than a substitute for the actual experiment.
The statistics and further observations revealed some interesting results:
• Additional experiments were attempted outside those requested, thus broadening the knowledge on this area of engineering.
• The lab was accessed outside normal opening hours allowing greater flexibility.
• The experiments were accessed by overseas students.
• Students who struggled with concepts could repeat the experiments.
• Mistakes made in the lab could be revisited and corrected.
• Students who felt intimidated working in a group (e.g. a solitary female) could repeat the experiments on their own.
• Distance learning students now had an opportunity to undertake “hands-on” lab work.
One challenge with this approach espoused above is the suggestion that the labs are only used to, “reinforce an experiment” rather than replacing the traditional lab experiment with a remote lab. For these labs to be effective in a distance learning setting it is ideal that they are the only experimental experience the students will be exposed to, as the students are unlikely to want to travel to a residential university to undertake the experiment.
Collaboration with Remote Labs
A remotely accessible rapid prototyping lab was established (in 2006) for three universities: Tennessee Tech University, Sam Houston State University and Murray State University. Each remote team was able to view the lab located at Tennessee Tech University, use a scheduling tool to track online their part submission and delivery, observe the entire manufacturing process and receive the parts via the postal service.103 Courses at the various universities which used the tool included Product and Tooling Design, Computer Aided Drafting and Engineering Graphics. Despite the lab being remotely located, the students learned about parts with tight resolution and precision (with assembly problems), sturdiness of parts (due to making them too fragile with thin walled components) and shrinkage and expansion. Feedback received from students indicated a high level of satisfaction with the lab.
Remote Non-destructive Testing Lab and Course
Non-destructive testing is a powerful technique for confirming the specified quality of structures and components.104 Drexel University’s Goodwin College of Professional Studies set up a local and remote non-destructive testing (NDT) lab. The lab was created as an adjunct to the NDT course for undergraduate Applied Engineering Technology students. This lab and course introduced the students to ultrasound measurements where they would learn about the characteristics of sound in different materials and how to work with the related ultrasonic NDT equipment. Other objectives were to use ultrasonic inspection systems for quality control analysis.
The traditional lab environment was extended to offering a video conference teaching facility; thus allowing for remote students and those at other colleges to attend the course and access the expensive equipment. A Polycom videoconferencing system was used with a Sony camcorder for capture and recording of the experiments. UltraVNC software allowed for control and data transfer from the portable ultrasonic flaw detectors and camcorder. Thus, one could remotely control and change any setting of the Flaw detectors such as calibration and evaluation of test objects. A lab assistant was still required for initial set up of the videoconferencing system, the NDT equipment and handling of the transducers. The calibration of the NDT equipment could be done remotely. A review of feedback from the remote students still had to be conducted but it appeared to be a workable way of conducting NDT education.
HVAC Remote Labs
The Department of Mechanical Engineering Technology at Purdue University provides an Associate Degree at seven campuses in Indiana.105 The largest enrolment and greatest collection of lab equipment was located at the one campus and there were insufficient resources to duplicate the equipment at the other six campuses. The modern Building Automation System (BAS) monitors hundreds of data points (such as pressure, temperature, airflow, power, location of people etc.) and makes this information available via Ethernet (and to the internet), thus allowing universal access and making a remote lab easy to configure. This makes it easy to access this information remotely from a networked computer.
Two small HVAC systems at Purdue University comprise a small-scale forced air system and hydronic system (for heating and cooling). A web-based interface provides an overview of all the equipment and sensor values. Four of the 13 ABET educational objectives were achieved with these remote labs. The students were assessed with a pre- and post-lab experiment web-based tests. The overall post-lab scores were disappointingly low and showed only a slight improvement (and in the one test, the post-test actually indicated that the remote labs actually had a negative result on student learning!). Most students were supportive of the remote lab approach (90%) and appreciated the flexibility. In conclusion, it was felt that remote labs are a useful adjunct but traditional labs are still required especially for teaching troubleshooting, teamwork and safety concepts. Especially with remote labs, accessibility to lab instructors is critical.
Computer Integrated Manufacturing Labs
Two remote labs were built at Morehead State University for motion and process control.106 The web-based motion control system was comprised of a PC with LabVIEW software (which also publishes the control panel to the web), motion control card, stepper drive, stepper motor and webcam. The velocity and acceleration of the motors can be varied and a waveform graph provides a history of operation. A process control lab comprised LabVIEW (which publishes the control panel to the web), a NI Fieldpoint controller with I/O modules, three tanks, two pumps, five on / off valves, two modulating valves, three temperature sensors, three level sensors, two pressure transmitters and a flow rate transmitter.
The specific lab sessions that were undertaken included Introduction to Motion Control, Programming Motion Control, Introduction to Process Control, Programming for Process Control and remote measurements and design of an automatic manufacturing cell for remote control and monitoring. Feedback from students was generally positive although security concerns meant the labs were not available 100% of the time.
Remote Lab based on Vibrating Bridge Structure
An experiment based around a vibrating bridge structure using two types of smart materials to control and dampen vibrations was designed.107 Typical demonstrations possible were onset of resonance, effect of damping ratio on resonance, structural vibration damping, the effect of system stiffness on resonance frequency and passive vibration damping.
Both manual and computer control modes were provided. An operator could manually adjust the stiffness and damping ratio by adjusting knobs. A Data Translation USB-based data acquisition board acquired data (incl. temperature/current/accelerometers) and provided control through three virtual knobs. LabVIEW displayed the readings on the internet through the use of LabVIEW’s internet toolkit. Thus, this allowed for remotely conducted experiments.
The lab was demonstrated in various courses such as earthquake engineering and vibrations and control labs with most students rating it “effective” or “very effective”.
Real 3D Online Robotics Visualization
With only 2D feedback to the observer, online labs can be challenging due to the lack of depth perception and limited visual information overloading the cognitive understanding.108 The cognitive overload is increased when working with miniaturized equipment and with no instructor present. One should bear in mind that with these systems, a considerable amount of mental effort is required to convert the 2D images into 3D. At Drexel University, a 3D image was created for a robotics class, where the students used polarized glasses to view the 3D video that was projected onto a silver screen in the classroom. Students believed that they had a considerably improved experience.
A low-cost vibration remote lab simulator was developed at the Queensl and University of Technology, Australia.109 This lab demonstrated basic vibration theory learned in the class and provided for a series of experiments. These experimental results were compared with theoretical results achieved using the MATLAB package.
The remote lab was based on test samples comprising a range of cantilevers of different sizes and masses. Two webcams were used to give a realistic view of the lab. One recorded the overall view of the lab and other the mode shapes of the cantilevers. The lab was based around a vibration shaker controlled by a microcontroller (via a power amplifier). The vibration transducer data (a piezo-electric accelerometer) was fed back through the microcontroller as well. At low frequencies, the waveform is sampled and the peak value determined. At frequencies higher than 20Hz, a hardware peak detector was used, as the maximum sampling rate is 100Hz. A menu-driven system for the user was based on Visual Basic. In response to commands from the PC, the microcontroller instructed the signal generator to produce the required frequency at a specific amplitude.
Two tests were performed: A fixed frequency and a frequency sweep. The experimental tasks performed by the students included (with resonant mode frequencies in brackets) a short cantilever with a fixed frequency (19.2Hz), a long cantilever with fixed frequency (4.6Hz), a long cantilever with fixed frequency (28.6Hz) and combined short and long cantilevers with a sweep frequency test from 15Hz to 35Hz.
The students logged into the lab computer using the Remote Desktop Connection and then had to activate the video cameras and shaker controller. The initial experiments with the remote lab showed a tight correlation between the theoretical and experimental test results. The initial group of students was satisfied with the lab and the idea was to exp and the use of this lab to a larger class environment.
Wind Tunnel Remote Lab
The lift and introduction to aerodynamics thermofluids experiment was conducted remotely from the Rochester Institute of Technology (Rochester, New York) using a Flotek Wind Tunnel in Ohio.110 The wind tunnel was upgraded with an airfoil stepper motor controller and data acquisition board to read 16 channels from pressure sensors. The performance of a cambered airfoil was examined at different wind velocities and angles of attack using a motor controller. LabVIEW was used for the remote lab client and server. An initial problem encountered was accessing the LabVIEW controls and interface through the web page even though computer security settings had been adjusted. This required downloading the LabVIEW executable file and manually installing it. An irritating problem was in having two windows, one for the LabVIEW control and monitoring and the second one for the video streaming. A better solution would have been to have a dual monitor or having the streaming video and LabVIEW in one window. The audio was very helpful in providing local ambience. It was suggested that key components of the remote lab should be available at the remote site to add realism to the experiment (in this case two airfoils). A further suggestion was for the instructor to demonstrate the lab and then provide review time once the students had completed their experiments. Overall, the objectives of the experiment were achieved with the remote lab providing an equivalent or better experience than local labs. Students were able to underst and losses and measurement error in comparison with their calculated theoretical values.
Tensile Testing Remote Lab
Georgia Tech Regional Engineering Program (GTREP) put together a tensile testing remote lab for obtaining stress-strain data from a sample of material.111 A lab technician loaded the specimen onto the load frame, activated the webcam and positioned the load cell and extensometer. LabVIEW was used for the remote lab server and client software. The student would use MatLab to analyze the data. This lab could easily be extended to torsional and fatigue testing. GTREP is a collaborative program between Georgia Institute of Technology, Armstrong Atlantic State University, Savannah State University and Georgia Southern University.
Measurement of the Speed of Sound
This lab was based around LabVIEW that provided the interface and allowed measurement and control through VIs (Virtual Instruments).112 The student moved the microphone to the smallest (reference) point from the loudspeaker. After initiating a sound through the loudspeaker, a comparison on a LabVIEW oscilloscope window would be made between output (loudspeaker) and input (microphone). The process was then repeated for increasing distances. The room temperature would be observed and then the student would use linear regression to compare the experimental speed of sound with the theoretical version.
Online Wind Tunnel Laboratory
An online wind tunnel with a model of an airplane wing and other objects based on both remote and virtual labs was built at the Stevens Institute of Technology.113 This provided the students with real-time measurements for pressure, velocity and drag force with streamed audio and video.
The wind tunnel was adapted for remote control by allowing for remote turning on and off of the power supply, adjustment of the airflow velocity by setting the fan speed, and in changing the angle of attack of the body (“wing”) in the test section using a stepper motor controller. A data acquisition system allowed for real time reading of 16 channels of pressure data.
Remote control was built around a four-tier architecture. The first layer was the webpage that allows students to communicate with the experimental instrument. The second layer was the web application that accepted requests from the webpage and passed data back as a result of these requests. The third layer allowed for interactions between the web browser, database and experimental controller. The actual control of the instruments and webcam formed the fourth layer.
A separate simulation (WebMax) was set up for each of the two different types of objects in the airflow: an airfoil and a body. This allowed for comparison between the remote lab and the simulations and provided a more effective approach than a lab with traditional instrumentation. The remote access of the expensive wind tunnel from a variety of other institutions would surely widen access to this important technology.
One-degree-of-freedom Mechanical Vibration System
The Stevens Institute of Technology built a remote lab in 2006 based on a one-degree-of-freedom free vibration experiment for a junior level course on mechanisms and machine dynamics.114 The user could control the inputs of initial displacement, experiment run time, sample frequency, lighting, audio and video. The students were given the values of mass and spring stiffness and then had to calculate the undamped circular natural frequency, undamped natural frequency and undamped vibration period. They then conducted the experiment and determined the damped vibration period, damped natural frequency, damped circular natural frequency, logarithmic decrement, damping ratio and damping coefficient from the experimental data. The determination of the appropriate sampling rate was critical to achieving the correct parameters (as the resultant waveform would change dramatically with sampling rates lower or greater than the Nyquist sampling rate).
The Solar e-lab
The remote lab developed within the MARVEL project of the Leonardo da Vinci program, comprised a solar energy conversion plant comprising two solar collectors on the roof of the lab, an insulated thermal storage tank and associated instrumentation, piping and other fittings.115 The Testpoint software tool, running on a PC connected to the instrumentation and control equipment, was used for data acquisition and control. All collected data were stored in Excel or Word and could easily be accessed by the user. The remote user could access the lab through a PC, which acted as a PHP-based web server.
The student first had to pass a pre-lab quiz before accessing the scheduling tool, all of which were located on the web server. The lab allowed for the student to access the instrumentation comprising temperature, flow rates and solar radiation. There were two main experiments: Firstly, investigating the variation of temperature across the storage tank and secondly, the instantaneous efficiency of the collector and the rate of thermal energy removed from the storage tank for consumption.
Feedback from visitors and users of the remote lab has been positive with a moderate to high degree of satisfaction expressed. The lab website has been accessed by users from 75 countries; and over the period November 2004 to October 2008, there were more than a million website hits. The presentation on solar energy was the most popular. It was suggested that two-hour booking slots were too long and should be reduced in time.
A remote lab (an eLaboratory) at the University of Toronto was applied to two labs for third-year aerospace students at the University of Toronto with a mixed response.116 Students either preferred remote access or had no preference. Support from lab assistants purely in the text chat mode was considered inadequate and full audio and video was requested. Technical problems with the lab were immediately associated with the user interface and use of remote technologies. Finally, more work needed to be done on the graphical user interface to make it more transparent and improvements made to reduce network latency and increase bandwidth.
International Collaborative labs in Mechanical Engineering
In a joint effort between the Cologne University of Applied Sciences and the University of North Florida, a mechanical engineering remote lab was created based around a Twin Rotor Plant.117 For simplicity, the twin rotor was modified from a Multiple Input Multiple Output system to a Single Input Single Output system. The students had to calculate the optimum PD/PID Controller parameters and observe the resulting different step responses. The experiment had two parts: A simulation using MatLab or Simulink and using the remote lab to compare the two results.
National Instruments LabVIEW software and hardware was used for the interface. The Microsoft Access database was used to store the experimental data.
Although enthusiastic about this new remote approach to experimentation, students nonetheless still preferred the hands-on electromechanical plant experiments. Other issues which required further work, were the need for better visualization of the actual lab with improved cameras and the need to make the twin rotor system more stable so that the remote lab results can be better aligned with the theoretical simulated results from MatLab. Other challenges were the network security firewalls with the various institutions restricting internet traffic. Finally, some intervention was required in the remote lab to support the equipment.
10.6 Chemistry, Chemical and Process Engineering
Remote Analytical Lab118
Access to the remote analytical lab equipment is based on using Windows Server 2008 with remote access. The lab comprised a web server and application server connected to the actual equipment. A router acts as an interface to the remote student clients. When the client connects to the lab through the website, a request is made by the client at port 80 to the router, which is then configured to forward the request to the web server.
A number of remote analytical labs were set up. The first one was to determine ascorbic acid in lemons. The student interacted remotely with the instrument, which was a potentiostat for electrochemical measurements and a calorimeter. Before commencing the actual lab, the student is expected to undertake a simulation exercise to reinforce his understanding of cyclic voltammetry. The student then connects to the real lab equipment, a potentiostat, and the measurement is done using the vendor's software. The student is expected to calculate redox potential, peak current and other parameters such as diffusion co-efficient.
Other remote experiments included determination of metal ions in groundwater (using a potentiostat) and measurement of glucose in a solution using di-nitro salicylic acid reagent (with a calorimeter).
Chemical Engineering and Web Labs
Remote labs have been used in the chemical engineering with great success. At the Massachusetts Institute of Technology (MIT), remote labs were used to supplement the course on transport processes (with 100 students per year taught in the third year), which covers the principles of heat and mass transfer, steady and transient conduction and diffusion, radiative heat transfer and convective transport of heat and mass.119 A supporting remote lab comprised a set of three heat exchanger experiments, two radiation / convection experiments and three conduction experiments. The lab equipment is connected via a USB interface to a computer with a DLL to access the input and output parameters of the experiment. Function calls to the DLL are made from the ubiquitous LabVIEW program. Remote access for the instructors was through VNC (Virtual Networking Computing) allowing complete control and viewing. The students used remote access through LabVIEW. Additional software is provided for user registration, authentication and scheduling of lab sessions (using the Microsoft .NET and C#). A survey revealed that students were generally positive about the labs but harsh in their criticism of problems in the interface and hardware/software problems.
The University of Cambridge third year Chemical Engineering students used the MIT iLabs heat exchanger experiment with a shell and tube heat exchanger. Despite some reservations about the “lack of reality”, students considered these experiments to be considerably better than doing simulations or calculations.
The University of Leipzig has various stages to go through in undertaking their remote labs from an introduction describing the background, objectives, hardware used, procedure in how to operate the lab, an offline version of the lab, an online version of the lab and then finally, the evaluation and discussion. A standard web browser and Java is all that is required to operate the labs. It was possible to observe the entire experiment in real time using video and audio. Seven experiments have now been developed and shared between the Universities of Leipzig and Oldenburg: heat transfer, adsorption, residence time distribution, hydrolysis/saponification, dehydration, temperature control and remote control.
Remote Lab for Chemical Instrumental Analysis
At Athabasca University and Northern Alberta Institute of Technology remote labs based around 15 different analytical instruments were set up.120 Most modern analytical instruments are networked and computer controlled these days; hence they can be easily accessed remotely through the internet.
The key components of the remote lab were:
• Public Information describing the project to visitors.
• Password protection to eliminate unauthorized persons from accessing the instruments.
• FAQ and Help Section to help with common problems.
• Connection to the instructor for assistance.
• Tutorial on Chemical principles.
• Qualifier exercises to get students to a minimum skill level.
• Scheduler function to provide instrument time for users.
• Instrument access.
• Webcam access to view instruments.
• Reference library databases to compare measurements with ideal manufacturer results.
• Supplementary resource materials.
A range of experiments was performed in chromatography and spectroscopy topics. There was no significant difference in grades between students working remotely or locally. It was noted that it was important to ensure that the remote lab content and level is matched to the particular student. For example, an advanced analytical lab may not be suitable for a first-year chemistry student. One concern students had with remote labs was the lack of access to a face-to-face instructor. Balanced against this was the concern that students prefer not to struggle through the text and want (verbal) immediate solutions from instructors. Some other vital features of the remote labs were ensuring that cameras are used to make the experiment more believable, the 24/7 flexibility of remote labs and problems working with the lab. Although this last point seems strange, working through issues is seen to be a necessary part of completing a successful lab.
10.7 Nuclear Engineering
Broadcasting Video and Data for a Nuclear Engineering Lab
Although, the authors from the department of Nuclear, Plasma and Radiological Engineering at the University of Illinois at Urbana-Champaign are cautious in their assessment about whether both distance learning and remote labs will be as meaningful as the classroom experiences, they feel they can be made more realistic with the right approach.121
It is instructive to review their description of a remote lab which places emphasis on the video capability of the lab. This remote lab is based around a boiling heat transfer experiment requiring a measurement of the heat transfer coefficient before, during, and after film boiling, providing the student with an understanding of the various boiling regimes. A metal sphere with two thermocouples embedded in it is heated to 420ºC / 788ºF and then submerged in a bath of near boiling water. The experiment is repeated with a copper and steel balls and the temperatures are measured using an USB-based temperature measurement device together with LabVIEW software from National Instruments. A Canon network camera is used which can transmit video at 30 frames per second and has built-in web and FTP server capabilities supporting up to 50 viewers simultaneously. With 26X optical and 12X digital zoom in, 200º panning and 120º tilting, a remote client can access any part of the experiment. An audio module built into the camera adds more realism to the experiment. The remote computers require both a web browser and the LabVIEW and Java run-time engines installed. This lab has been tested but no comments are made about the reaction of students to the lab.
Nuclear, Plasma and Radiological Engineering
At the University of Illinois at Urbana-Champaign Department of Nuclear, Plasma and Radiological Engineering a series of remote labs was set up.122 Initially it only provided measurement and no control by remotely located students. The remote labs were based around LabVIEW allowing remote viewing of the control panels through a web browser.
Two experiments were set up. The first one was to measure the heat transfer co-efficient during various water boiling regimes for two different metal balls (copper and steel). Two thermocouples were embedded in the ball–one on the surface and one internally.
A sophisticated webcam with controllable zoom, pan and tilt capability and fast frame rates (with audio) was able to be accessed simultaneously by 50 multiple users. Two large screen monitors at a distant monitoring lab enabled for more detailed viewing. Centra web conferencing software was used between the remote lab and receiving sites.
An USB-based temperature measurement device (Measurement Computing Corporation) with eight differential thermocouples, RTD, thermistors and semiconductor temperature sensors was used for monitoring.
The second experiment comprised a gamma ray spectroscopy experiment was also placed online. This allowed estimation of gamma ray energy both locally and at a remote site by measuring the voltage in a scintillation detector.
Both experiments were considered realistic experiences for students of remote labs.
Neutron Beam Experiments based on iLab
The iLab shared architecture was used to run a range of neutron experiments at MIT.123 The NI LabVIEW software (Integrated Interactive Lab Server) was used for the experimental interface. The experiments which are part of the course on Nuclear Engineering included:
• Measurement of the Maxwell Boltzmann distribution of thermal neutrons.
• DeBroglie relationship of kinetic energy and momentum of thermal neutrons and Bragg Diffraction.
• Beam Depletion or Shielding effectiveness in a neutron beam.
The spectrometer-based iLab is an interactive experiment requiring users to schedule experiments in advance. This allowed the operators in the reactor control room to manually open the beam port.
The procedure was for students to log in to the service broker, select the spectrometer experiment and redeem their earlier reservation tag. The service broker checks that the user has a valid reservation and that she is allowed to use the spectrometer experiment. The user was then able to launch the experiment.
Two web cameras of each experimental setup were provided so that students could observe the experiments underway. These were critical to providing the students with a feeling of presence.
Software and hardware safety interlocks were provided to eliminate any collisions of components and to ensure the various items were only operated over defined ranges. Most students commenced their experiments by working in the physical lab before taking on the online option.
The great advantage with online access is in achieving longer lab times; thus better quality data sets for improved analysis. Students can also easily repeat the experiment if they identify problems. Overall, the online labs achieved comparable educational outcomes to the traditional physical labs.
10.8 Information Technology (IT)
Information Warfare Courses
Iowa State University (in 2004) offered the only information warfare course via distance learning.124 In addition to a textbook, internet resources are used as computer and network security is a rapidly evolving field. Apart from the need to institute a physical break in to the compus, the labs were well suited to distance learning. The distance learning students were two weeks behind the on-campus students, hence care was required in handing out solutions. The first six labs were focused on tools and processes to attack and secure a network of computers. The final lab was the break-in lab that was to break into a company network and gain as much information as they can (such as passwords and usernames). They then had to write a report detailing how they broke in and how they would fix the problems found. When the exercise was running, the instructor had to check in every few hours to correct any problems that might arise.
Overall the course has been very successful with the students rating the labs highly.
Remote Lab with Instructor Support
A remote lab was set up by the three authors from the Learning Lab in Lower Saxony to test the degree of support required by a tutor.125 As was pointed out, engineering students need to acquire problem solving and creativity strategies to be successful in their careers. Hence, labs are a great way of acquiring problem solving skills. A few key characteristics of these remote labs with synchronous tutorial support to the students were:
• A problem-based learning environment.
• Synchronous learning on live lab equipment.
• Support with asynchronous tools such as email for dispatch of the lab results.
• Asymmetric learning (the tutor knew more than the students).
• Small groups of three or four.
• A duration of a few hours for each experiment.
The remote lab consisted of the students working on Java programming for picture generation by laser deflection where the compiled code had to interface to data acquisition and control hardware.
The working environment for the student comprised a computer screen with the left part allowing students remote access to the lab where they can select and control cameras; and switch on and off the embedded system. The right side of the window allowed different users to communicate with each other using video/audio and text. The remote lab using desktop sharing was based on the popular VNC software and 19 students in electrical and computer engineering took part in the lab. The results confirmed that remote support with desktop sharing and video chat was as effective as that from a local tutor to the students and achieved a similar level of instructional quality. However, the authors suggested that this might not be as successful for a lab requiring considerable soft skills where social cues are important. Audio chat and the combination of video chat and desktop sharing were mainly used and were extremely important for success in referring to the remote tutor. The use of the video chat facility did compromise the quality of the audio, not because of the bandwidth usage but the high CPU load of the student’s client application running the VNC software. Application sharing as opposed to desktop sharing should be considered here, if CPU overload is still an issue.
Virtualization and Cloud Computing in Intrusion Detection Technologies education Virtual lab systems were deployed at East Carolina University to improve efficiencies and cut down on costs.126 Virtualization allows for multiple operating systems to run concurrently on one physical computer. Services are allocated on dem and to users–after the reservation terminates, the physical server will have resources freed up to host a virtual environment for others.
Virtual Computing Lab (VCL) is a free, open source, virtual lab automation system developed at North Carolina State University. Another alternative is VMWare vCenter Lab Manager (VLM), a commercial package developed by VMWare. Initially, students used virtual machines on their personal computers for hands-on labs. However, this approach was not easily scalable for labs requiring multiple machines and considerable RAM and CPU power (e.g. in one case, a host was required to run 74 virtual machines concurrently without degradation in performance), where a student’s typical computer simply couldn’t cope. It was also easier for an instructor to monitor the lab and student activities with a centralized approach.
An Intrusion Detection Technologies course was offered both face-to-face and for distance learning students with all labs offered online using VMWare virtual labs.
Students showed a definite preference for virtual labs, whether they be centralized (for significant requirements) or decentralized (e.g. for minimal requirements with one virtual machine).
Remote Lab for Intrusion Detection Systems
A remote lab for intrusion detection systems was constructed at East Carolina University for remote access by students using a local campus-based LAN with student access via a Virtual Private Network (VPN) connection.127 Students control the local computers (hosts) through a Remote Desktop Web Connection. All experiment–based lab resources resided on the LAN file server, from which all students accessed the necessary experimental software. The design criteria were based around:
• 24/7 availability so that students could access it any time from any location with a minimally configured laptop computer.
• Flexibility in configuration of the lab with no requirements for instructor involvement or hardware modifications.
• The highest level of reliability, allowing students to easily execute the labs with no possibility of failure. This means designing the labs to have the minimum possible hardware for all the experiments.
• Economy. Providing for lowest cost and thus no redundancy.
There were two main types of experiments: HIDS (presumably Host-based IDS) where each student only needed to operate on the one host with all the software installed on this host; and NIDS (presumably Network-based IDS) where a group of students operates on the network with some hosts to launch attacks and others as IDS sensors to detect these assaults.
Challenges with the network were the limited network speed (especially in achieving quick remote lab access) and scheduling problems especially when one group overshot the time on their specific experiment.
An Attempt to Cut Down Travel to Labs On-Campus
The University of North Dakota regarded labs as one of the major restrictions for distance students in completing the chemical, electrical and mechanical bachelor of engineering programs (as well as the varied asynchronous delivery requirements placed on staff coping with students at different levels of progress).128 A serious attempt was thus made to halve the amount of time students would be required to spend on campus from twelve to six assignments using simulations and remote labs.
The online lab assignments were based on authentication of the student to the lab, provision of the necessary background theory and assignment instructions, online experimentation via virtual and remote labs, obtaining the necessary experimental data, analysis of the data and finally, report writing of the experiment. National Instruments’ LabVIEW software was used as the interface between the lab equipment and in publishing the labs on the web. A video camera was also added to give improved realism. The three lab courses that were redesigned for 50% online content included chemical engineering, electrical circuits and mechanical engineering.
The simulation lab included a process simulation using ChemCad software to determine the best solvent for a light hydrocarbon absorption column. Students had to load the program on their individual computers but it was hoped in future to allow access to the software loaded up on-campus computers. A steel selection simulation comprising images, videos, text and tables showing details of steel was another virtual lab. A third lab based on operational amplifier circuits was created using LabVIEW VIs which were then published to the internet. Both input and output waveforms could be observed using different ac and dc input voltages and impedance values. Assignments were provided through the Blackboard LMS. Finally, a PLC simulation lab was provided using LabVIEW that displayed the external wiring, output devices and switch inputs (push buttons and toggle switches).
In addition, remote labs were provided with a range of experiments ranging from process dynamics and control using a vertical cylindrical storage tank (with level detection) to demonstrate process dynamics of first order systems and PID Controller tuning. LabVIEW was used to display flow and control results as well as to input flow rate setpoints and controller tuning constants.
An op amp circuit was physically set up using a National Instruments data acquisition board to write and read the required analog and digital signals. In addition, a switching matrix was used to switch between components. A webcam was used to add more realism to the lab.
A steam turbine power plant model with LabVIEW was used to experiment with a working plant with such parameters as boiler temperature, pressure, turbine inlet and outlet temperatures and pressure, fuel flow rates, generator current and voltage. Stepper motors were added in for additional remote control of the steam admission valve as well as the load rheostat. For safety reasons, the master switch, burner switch and load switch were locally controlled.
A vibration lab was created to measure natural frequencies and mode shapes of a vibrating beam. A beam was supported at each end with an electro-dynamic shaker, audio source monoblock amplifier and single axis positioning table. On the table a capacitance probe was situated to measure the displacement at varying points along the beam.
Finally, the ubiquitous programmable logic controller physical set up using Rockwell PLCs connected to PCs with LabVIEW and PLC programming software. A digital camera (640 x 480) with remote pan and zoom capabilities was used to observe the PLC LEDs and external devices. Inputs to the PLC I/O modules were controlled through pushbutton and toggle switch computer screen icons connected to a data acquisition board.
Limited assessments of the conversion of the labs concluded that this change was well received. However, the physical response time for physical control was especially slow for international students and further work was required here.
Marine Instrumentation Forms a Remote Lab
A group of three universities and two oceanographic institutes has installed instrumentation and cameras on the ocean floor and on the water's surface to monitor oceanographic and meteorological activity.129 This remote undersea lab has often been used in the classroom to demonstrate experiments such as collecting water samples to analyze pH and other parameters and also to examine samples under a microscope. Correlations between the atmospheric conditions and marine and water life can be shown. The exposure of students to authentic research such as this increases the student's motivation and understanding of lectures. This underwater lab has been very busy, as students from many other universities throughout the world have taken advantage of this expensive but very useful facility.
A Pharmaceutical Science Remote lab
A great example in this area was the incorporation of a gas chromatography-mass spectrometry (GCMS) instrument into the Integrated Laboratory Network at Western Washington University.130 The Faculty of Pharmaceutical Sciences at the University of British Columbia with an enrolment of 140 in their BSc in Pharmacy offered a third year course in pharmaceutical analysis techniques but without access to an expensive GCMS thus weakening the laboratory component. The University of Washington had created an Integrated Laboratory Network (ILN), which had the objective of using internet technologies to incorporate scientific instrumentation and course materials into the classroom and lab environments. The ILN has several high-use expensive instruments such as gas and liquid chromatographs, mass spectrometers and a scanning electron microscope.
Microsoft’s Netmeeting, a web conferencing program, was used to access the GCMS instrument remotely; with additional features of audio, video and synchronous chat. Approximately 70% of the students felt this improved student learning in allowing students remote access to an expensive item of equipment. There were, however, problems with poor quality microphones, webcams and a complicated instrument interface. There was no actual improvement in the final mean examination grade with the use of this facility, but it was deemed useful to continue and exp and usage of this expensive device in the future.
Supplementing Lecture Courses
Georgia Institute of Technology created a program called TESSAL (Teaching Enhancement via Small-Scale Affordable Labs) to enhance lectures with an innovative set of portable labs for electrical, mechanical and computer engineering courses.131 Over 1244 students have undertaken them. These labs can be conducted either at home or in class, in groups of two to five students, and are oriented towards illuminating a difficult theoretical concept, being low-cost and portable, and finally, having an online component. One of the major challenges has been in motivating instructors to take ownership of these labs because of the additional effort and risk in getting to work smoothly. This problem was addressed successfully by designating technical assistants to support a set of labs.
A few suggestions on running the out-of-class labs successfully included making the assignments mandatory, using a reservation system to ensure labs are available timely, penalizing groups for being late, providing adequate support and transporting the lab equipment in sturdy containers. Similarly, suggestions on effectively running in-class labs included testing modules before the class, providing adequate time for undertaking the lab, ensuring students are prepared for the labs (including provision of videos) and providing adequate technical support.
Physics Remote Labs
At the Berlin Institute of Technology, over 500 students participate in an undergraduate Physics course, and this places huge demands on lab equipment especially for expensive equipment such as for Raman spectroscopy or dangerous matericals, such as radioactive materials.132 A series of 12 remote physics experiments (six classical and six modern ones), also referred to as, “the remote farm”, have thus been set up in conjunction with the Moodle LMS which everyone can gain access to through a browser. The students are mainly engineering students working in groups of three who undertake six remote experiments (and after analysis of the experimental data produce a report).
Each experiment is structured with the following resources:
• A description, the experimental setup and tasks to be undertaken.
• A simulation of the actual experiment.
• Remote experiment.
• A discussion forum, wiki and chat facility.
LabVIEW is the underlying software tool for controlling the experiments, both locally and for remote access.
A key element in support was the provision of two sets of tutor teams; a technical group that designs, builds, programs and maintains experiments and a teaching group. Both groups support two labs and the associated students.
Feedback from the students in the 2008 / 2009 semester was somewhat positive, with 64% of participants believing that working with remote experiments is very important for their future careers as engineers. There were negative comments on the lack of user-friendly graphical interfaces as well as instability in some experiments.
An important issue with physics (and engineering) is to underst and how the theory, physical model and experiment inter-relate and to be able to reconcile the similarities and differences.133 The opportunity presented by remote labs is to conduct this process seamlessly as there is effectively one graphical user interface.
Three sets of remote labs were compared with their virtual at the Berlin University of Technology (Institute of Solid State Physics). This included a magnetic hysteresis loop, the classical gas laws and a coupled harmonic oscillator.
Online Bachelor of Science in Engineering Technology
Excelsior College in New York has numerous successful online Bachelor of Science in Engineering Technology programs (such as electrical engineering and latterly a component within nanotechnology).134 Although software packages such as MultiSim, NI Circuit Design, LabVIEW, MATLAB, LogixPro and Xilinx can be used successfully for simulation, a minimum of two traditional hands-on lab courses is nonetheless required. This rule can be waived only if the student can demonstrate she has gained sufficient hands-on experience, generally through employment.
Improving Understanding in a Lecture-only Physics Course
The LiLa (Library of Labs) project is a European Union-funded project to set up remote and virtual labs.135 The concept is that a LiLa partner can collaborate with each other in using each universities’ labs in presenting their lectures. It was noted that many universities in Germany have a challenge with students being unable to fit in labs into their busy lecture schedules. Research was conducted on the Physics for Engineers course attended by 1300 students at the University of Stuttgart. As a result of the LiLa program, online labs were made optional for the students.
There were three phases to the online experiments: an orientation phase where the students familiarized themselves with the online experiment, the execution phase where they conducted the experiment and finally, the review phase where the progress of the students was checked and they undertook a short test. A survey was conducted on whether the students improved their learning success by undertaking the labs with mixed results. It was noted, however, that there was a strong correlation between the results of the final exam and the students who undertook the online experiments. It is possible that the students who undertook the experiments were already highly motivated and would have been successful in the exam.
The challenge was that the online experiments were not compulsory and hence only enjoyed a small take up (only 33 students out of a possible 1300 undertook all three experiments). The suggestion from the researchers was to make the experiments more “cool” to increase the motivation of the students to undertake these. However, it is doubtful whether this is possible. The only way is to ensure they add real value to the lectures with increased understanding and make them a key part of the course.
The important point with LiLa is to complement online labs with traditional hands-on training, which provides students with the opportunity to get familiar with real equipment and socialize and communicate with each other while working collaboratively.136
Remote Lab based on Atomic Force Microscope and LabVIEW
An atomic force microscope (AFM) was used to measure and manipulate objects down to the size of a single atom.137 LabVIEW is used to control the instrument. A simple comm and line language has been implemented to control the AFM with sequences of measurements requested. The structure of the lab has four layers:
• Hardware layer for the microscope and robotics for the sample stage.
• Middleware layer containing the entire functionality (and list of valid commands and security management).
• Interface to a graphical user interface (either local or remotely located).
• The Graphical user interface.
An expert (full range of commands allowed) or novice mode was available. Up to five simultaneous users can use the remote interface. Full video was essential for remote usage. The instrument was even usable by high school students with great success achieved here.
Fast Fourier Transform Demonstrated in an Optical Experiment
At Stanford University, a Cyberlab was based on an optical processor.138 Collimated light is incident on a selected object from a laser. The transmitted light is then Fourier transformed by a convex lens. Spatial filtering is performed in the back focal plane and a second lens provides another Fourier transform; the resulting image is then viewed on a CCD camera. The experiment allows for different objects, filters and lenses to be selected and placed in the path of the laser beam. The physical Fourier Transform can be compared with the theoretically derived one. Noise in the system added to the experimental random and systematic errors makes for discrepancies in the results.
An electronic lab notebook was used to record the experiment providing classical features of data recording and note taking but also a complete record of all correspondence with others.
Student responses were positive, although a need was expressed for more independence in operating the experiment to bring it closer to a traditional hands-on lab.
Remote Calibration and Testing of Instruments
Remote calibration of instruments is an opportunity to minimize on the downtime that could occur when they are transported to a calibration laboratory.139 There are some security issues as the installation is done by the customer and not under the direct control of the calibration lab personnel who have to sign the calibration certificate. Hence the procedure is required to be reliable and secure with minimal local human interaction required. A hardware device was interposed between the instrument (and sealed to the instrument to minimize possible tampering) and the GPIB bus to encrypt the data.
A full range of remote lab applications has been examined, from the popular electrical and electronics to mechanical, chemical, nuclear and IT. One concern is the sustainability of these labs, and that will be discussed in the next chapter.
Key Points and Applications
The following are the key points and applications from this chapter entitled: Remote Laboratory Applications.
1. The number of different remote laboratory management systems are as follows:
• MIT iLabs commenced by MIT in 2000.
• Australian LabShare Project with over 4000 students accessing it.
• Global Online Laboratory Consortium (GOLC) comprising an international group of universities initially based on the iLab Shared Architecture.
• Virtual Instrument Systems in Reality (VISIR) set up originally by the Blekinge Institute of Technology.
• Library of Labs (LiLa) is a European funded project to set up remote and local labs.