Ball balancing exercises
A low-cost PID setup for engineering students

Csurcsia, Péter Zoltán; Bhandari,Pujan

Introduction

PID controllers are the most frequently used controllers. Theoretical understanding of the system to be controlled and the working principle of PID controllers are crucial for closed loop control. This fundamental knowledge is - in principle - learned by all engineering student at the undergraduate level. However, understanding the practical aspects of the application of a PID controller and their connections to theoretical concepts must be combined in a clever way. This paper explores the process of the development of a low-cost, easy to manufacture demonstration setup which can act as the bridge between the theoretical and practical world of the control system knowledge. As a reaction to the COVID epidemy, this project is made with the philosophy that the students should be able take these setups home, or even replicate them themselves. The proposed setup comes with an interactive block diagram based graphical user interface which allows the user to observe the physical changes of the process in -nearly- real-time. The aim of the provided exercises is to comprehend the similarities and the difference between the theoretical and practical aspects of closed loop control. This paper explains the components of the setup, the development process, the recommended exercises and feedback from our students.

Ball balancing demonstration setup made up of wooden base and stand.

Exploded view of the demonstration setup.1-2: V-piece beam holder, 3: hinge piece, 4: V-shaped beam, 5: 8-mm bolt, 6: base plate, 7: servo motor, 8 servo arm, 9: servo motor holder, 10: camera stand, 11: L-Profile, 12: base leg foot, 13: pushrod, 14: camera, 15: Arduino Uno.

Overview of the ituitive GUI.