Stimulating Higher Order Thinking in Mechatronics by Comparing PID and Fuzzy Control

Abstract

Many studies have found active learning, either in the form of in-class exercises or projects, to be superior to traditional lectures. However, these forms of hands-on learning do not always get students to reach the higher order thinking skills associated with the highest levels of Bloom’s Taxonomy (i.e., analysis, synthesis, and evaluation). Assignments that expect students to take an expected approach to reach a well-defined solution contribute to a lack of higher order thinking at the college level. Professional engineers often face complex and ambiguous problems that require design decisions, where there is no straightforward answer. To strengthen the higher order thinking skills that these problems demand, we developed a project in our semester-long mechatronics course where students must evaluate two automatic control methodologies for an application without being given explicit performance criteria or experimental procedures. More specifically, the project involves determining the superior control method for leader-follower behavior in which a ground vehicle autonomously follows behind a lead vehicle. Laboratory exercises throughout the semester expose the students to the skills they need for the project: using sensors and actuators, programming a proportional-integral-derivative (PID) controller and a fuzzy controller, and using computer vision to detect the signature of an object. In the final course project, they go beyond implementing individual controllers and create their own evaluation criteria and experiments for making a design decision between PID and fuzzy control. We implemented this approach for three semesters, and our significant findings are: 1) students generally appreciate the aspect of working on a real-world and open-ended problem, 2) most teams developed creative performance criteria and methods for evaluating controller performance, clearly demonstrating higher order thinking, and 3) students discover that creating a comparative study is nontrivial due to the number of factors that influence performance, which mimics the practical problems they will likely face as engineers.