Computational Instruction through PLCs in a Multi-Disciplinary Introduction to Engineering Course

Abstract

This paper is focused on the inclusion of hardware-based Programmable Logic Controllers (PLCs) in a freshman engineering introduction course, Engineering Methods, Tools, & Practice II, at the University of Louisville’s J.B. Speed School of Engineering. Each academic year, more than 500 first-year engineering students are exposed to this interactive course, which introduces students to fundamental engineering skills – including teamwork, design, project management, technical writing, critical thinking, programming, communication (including written, oral, and graphical), 3D printing, and an introduction to engineering research.

Previously, this course culminated in a final project that combined construction and mechanical design of a windmill system utilizing data acquisition methods driven solely by Arduino programming and circuitry. The most recent iteration of the course added the instruction of PLCs prior to beginning the final project. The PLCs provide the students with a secondary form of computational methodology instruction.

A clear advantage of this PLC addition is that students become more aware of circuits that closely resemble those in industrial settings; moreover, it also forces students to have multiple hardware circuits implemented in their project. These circuits are required to share information and communicate via a serial interface. Another value of the PLC addition is the variation in programming and logic that is exposed to students. Modern engineering requires that students of all disciplines understand logical concepts of programming basics.

The inclusion of hardware based PLCs allows for the instruction of ladder logic, which is a more graphical-based form of programming that many students find easier to understand than traditional programming. Graphical programming and ladder logic are prevalent in many industrial settings. The course continues to employ Arduino programming as well as the ladder logic programing, which provides the students with a greater breadth of programming exposure.

The PLCs also expose students to hardware that they may encounter while employed on their co-ops, which can be beneficial when interviewing for their first co-op during their sophomore year. End-of-semester surveys show positive student feedback pertaining to the addition of PLCs to the final project.