An Internet-based Laboratory for Distant-Learning Engineering Students

Gaining practical experience with real equipment is one of the problems in Web-delivered distant engineering courses. However, there is a solution — a remotely controlled laboratory setup for carrying out experiments away from the campus. The experiment is not a simulation, but it involves actual laboratory equipment controlled in real-time from anywhere in the world using the Web. In this article, I’ll show how one such system works.

Distant learning overview

Distant learning is one of the fastest growing fields, and many colleges and universities are now offering courses over the Internet. Distant learners are typically adults, often with both family commitments and jobs, who cannot easily attend the campus for classes delivered in the traditional way. Institutions use a variety of technologies to deliver distant learning including satellite, TV broadcast, video tape, and the Internet.

Distant learning is not new. For example, the Open University (http://www.open.ac.uk) in the UK has been offering distant learning courses for many years. The method used by the Open University involves broadcasting the courses on the national TV, and also sending video tapes and written study material to the students. Engineering students receive a kit that enables them to carry out small experiments at home or in their places of study, and they attend the laboratories for some of the experiments, in order to fulfill requirements.

The methods of delivering distant learning courses have changed in the last decade with the speed and the accessibility of the Internet. Students can study course material located on Web pages, and they can send their assignments and answer quizzes using email. Students can discuss their assignments and other course-related problems with other students, or with their tutors, by joining the email discussion groups or Web sites.

For example, Stanford University (http://epgy.stanford.edu/) offers multimedia and Internet-based distant learning courses in the fields of mathematics, English, physics, computer science, music, and political science. The University claims that over 2200 students from 28 countries are enrolled in its distant learning programs.

Distant learning for engineering topics

Teaching non-engineering topics using distant learning techniques is relatively easy. The students study the online course notes and complete any required assignments in the specified time periods. There are no laboratory experiments to carry out, and the need to attend a formal lecture is minimal.

One of the problems in teaching engineering topics via distant learning is the lack of laboratories where the students can perform real experiments. For example, an electronic engineering student must perform various practical experiments using transistors, operational amplifiers, and so on.

During the last decade, there has been a definite trend towards the use of simulators in teaching engineering topics. There are several reasons for this. Firstly, physical experiments are costly to purchase and maintain, and secondly, there is a belief that simulators can replace the physical experiments. For example, students can use PC-based simulation packages, such as Multisim from Adept Scientific (http://www.adeptscience.com), to design electronic circuits and to simulate and observe the voltages and currents at various points of the circuit using virtual instruments such as oscilloscopes, function generators, and logic analysers.

While simulators can be quite effective tools in teaching, they are actually theoretical and cannot replace the practical experiments. In a statistical analysis experiment at Oxford University, the students regarded the output of simulations as “pretend” data. (See the research report by Hugh Cartwright, listed in the References at the end of this article, for details.) Students generally fail to relate the simulated data to real-life data.

I will describe the development of an Internet-based system, which enables distant students learning engineering to perform experiments in their own places of study, using real laboratory components and equipment. In fact, the students are able to perform real laboratory experiments and obtain results from anywhere at anytime. For example, they could be executing an experiment using their laptop PC while sitting at the beach, hundreds of miles away from the laboratory.

The prototype remote laboratory experiments system

We have developed a prototype system at the Near East University (http://www.neu.edu.tr) in the logic circuits laboratory. This system will be used in future distant learning education programs of the University. Near East University (NEU) is a private international institution of higher education founded in Nicosia, Cyprus, in 1988. Today, the University consists of a student population from 18 different countries, with seven faculties in 20 departments offering a variety of courses at both undergraduate and graduate level.

Previous remote laboratory control systems

Like distant learning, Internet-based remote laboratory control is not new. Frederick Senese and his colleagues at Frostburg State University reported an Internet-based chemistry laboratory where the students perform experiments remotely in order to determine the rates of fast chemical reactions. A Webcam collects images of the apparatus and experiments, and sends these to the students in real-time.

Christophe Salzmann and others outlined, in a paper presented in 1998, the requirements for real-time experimentation over the Internet. The year before, Denis Gillet and co-workers reported the concept of telepresence for developing practical experiments to teach automatic control via remote laboratory techniques.

The Remote Laboratory Experimentation Trial (ReLAX) project, also reported by Denis Gillet and others at the Polytechnic of Lusanne, connected experiments located at different Universities to the Internet. In this way, the Universities avoided the cost of purchasing and maintaining expensive laboratory equipment.

Christian Schmid described the design of an Internet-based laboratory at the control-engineering laboratory of the University of Bochum, Germany, in 2000. The project provided practical experience in the field of automatic control. Resource sharing among universities was one of the aims of the project, in order to reduce the cost and time for maintenance or development of new experiments. The system described used a Matlab/Simulinkbased computational engine (http://www.mathworks.com), together with the Quanser’s WinCon (http://www.quanser.com) real-time system to perform the experiments. WinCon is a real-time Windows-based application that runs Simulink generated code using a real-time workshop on a PC. The project makes animation of the plant models in virtual reality, which helps students to visualize remotely the operation of the actual plant.

Remote laboratory minimum requirements

The minimum requirements of a remote laboratory depend very much on the type of experiment to be performed, and the available budget. For low budget applications, the following software and hardware components will be required:

• Client computer hardware. This can be a standard PC, equipped with a modem and the ability to connect to the Internet via an ISP.
• Client computer software. There is a wide choice here. The low budget approach would be in-house development of client-server software, probably using the TCP/IP protocol.
• Server hardware. This can be a standard PC, equipped with a LAN network card and connected to the University Internet backbone. Additionally, depending upon the type of application, a PC input-output card will be required.
• Video camera. The choice is to use either a serial or a USB video camera. USB is preferred for higher throughput.
• Server software. As in the client software, there is the choice of either purchasing a client-server software package or having it developed in-house.
• Experiment kit. The experiment kit will have to be designed such that it can be used easily in remote laboratory applications.

Logic circuit teaching

The Faculty of Engineering at the Near East University offers undergraduate courses in Electrical and Electronic Engineering, Computer Engineering, Civil Engineering and Mechanical Engineering. All courses are two-semester, four-year courses. Students studying for the electrical and electronic engineering and computer engineering courses attend lectures on logic circuits as well as the compulsory logic circuits laboratory where they perform simple experiments on logic gates, flip-flops counters, shift-registers and so on. These experiments involve the use of breadboard-based development tools, power supplies, voltmeters, and LEDs.

As part of the distant-learning teaching for engineering students, the University has developed a remotely controlled, client-server-based logic circuit teaching system. Figure 1 shows the general structure of this system.

Figure 1 Structure of the clientserver based laboratory setup

Students are at the client side of the system where they use their own PCs to connect to the Internet from their location. Once connected, the students’ PCs run a client program that establishes communication with a server computer inside the logic circuits laboratory at the University. The server computer controls the physical experiment kit, sends student inputs to the experiment, and collects the results for sending back to the student. As described later in the article, special programs on both the client and the server computers control the experiment remotely. A digital input-out-put card inside the server computer provides the actual interface to the experiment. A video camera monitors the experiment and transmits video images to the client computer so that the student can see the progress of the experiment remotely and in real-time.

The students receive course notes and laboratory manuals with detailed description of the projects and instructions on how to perform them. We expect to develop more projects for distant-learning engineering students. One of the major problems in this area is the fact that it is not easy to have a flexible experimental setup where the students can change the configuration remotely. For some experiments in which the students must change components and then take readings, it is virtually impossible to have a remotely controlled system.

What one can do in such circumstances is to provide several experimental setups with different components where the students can move easily from one setup to the others. One can connect measuring devices such as voltmeters or ammeters to the experimental setup before the experiment commences to allow the student to observe the readings via the video camera.

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