Using Simulink, Matlab, and LEGO Mindstorms to Teach a Project-Based Control Systems Design Course

Teaching control systems design using theoretical design examples outlined in most textbooks has been found to be quite challenging for many engineering students. One major observation is the tendency for students to resort to a trial and error approach in the design process without realization of the adverse effects that such an approach can have in the real world. Computer simulations of analytical solutions do provide some insight but here limitations arise in interpreting the results correctly or in the visualization of the real system’s dynamics. This paper gives an overview of an approach that (i) allows the student to create and analyze the mathematical model of a real system, (ii) build a practical emulation of the real system using LEGO Mindstorms, (iii) observe the behavior of the system in real-time, and (iv) apply feedback principles using Matlab and Simulink to design the system to meet desired specifications. The first part of the course is an introduction to control theory using the classical approach. In the second part, students work in teams of three or four to design, build, and program a LEGO Mindstorms system of their choice that must perform stipulated tasks. The original system must not have any type of controller and must show that the desired requirements are not met. This provides an opportunity for the students to see how design constraints are established. Based on my observations so far, as well as on student feedback, students become very highly motivated by the design component of the course, and many end up with a thorough grasp of the fundamental principles of control systems design. The open-ended approach allows for creativity and flexibility in the design process, with both the instructor and students benefitting from an array of designs. A few examples of actual student projects will be presented. Motivation The incorporation of project-based learning (PBL) in the curriculum has been known to help students develop an intuitive understanding of the theory by providing real world applications that foster research and design. Bernard M. Gordon [1] presented a review of several institutions in the United Kingdom and Australia that adopted PBL in different types of engineering courses, and the positive impact the approach had on assessment. Students were encouraged to work in groups and document their progress throughout the process. Fernandez-Samaca et al designed an undergraduate electrical engineering control system course using PBL. A series of courses that had both lecture and laboratory components were offered with the project being the central element in the approach. Enikov et al developed the Aeropendulum Project which is a low-cost hands-on experiment suitable for a classical controls course. After using this project for a few years in the controls course at our institution, a missing component was the flexibility that would allow testing of other designs in addition to the pendulum. Golnaraghi and Kuo developed The Control Lab which consists of virtual lab control experiments. Matlab and Simulink are used extensively in simulations and controller design projects. However, in order to run the simulations a special applet, the Automatic Control Systems (ACSYS), must be used.