Construction of an On-line Education Course Using an Experiment System

This paper describes an on-line education course for control engineering. The course employs an Internet experiment control system for an inverted pendulum and ways of using the experiment system were investigated. Several improvements were made to the system to make it easy and safe for beginners to use. This system is suitable for various stages of the learning process. With it, a student can carry out system identification, design a controller, and perform simulations and experiments. The structure of the experiment system is shown in Fig. 1. The client side is a student and the provider side is the server of the on-line course. The provider is comprised of three parts: the plant (a cartand-rail-type inverted pendulum), a control machine, and the server. A client connects to the server over the Internet. The server and the control machine are connected via an RS232C cable, and an A/D and D/A converter board on the control machine provides input to and output from the plant. The server runs Windows 98 and the control machine runs PC-DOS 7.0. Three programs are executed on these machines to perform an experiment. The client program stored on the server machine is run from a WWW browser to set an experiment up. The server program, which is stored and executed on the server machine, processes commands from clients, supervises the control machine, and sends experimental results back to clients. The control program, which is stored and executed on the control machine according to instructions from the server, runs the plant. There are two main reasons that an inverted pendulum was chosen as the plant: first, since the plant is unstable at the straight-up equilibrium position, it is easy to use this plant to explain the concept of stability and stabilization; and second,