A Ball-on-Beam System with an Embedded Controller

This paper describes the design and construction of a ball-on-beam balance system driven by an embedded controller.This embedded control system is intended for linear controls education.The advantages of this system are as follows: first, it can be used for demonstrating proportional, PI, PD, PID, and velocity feedback controllers in action.Among these controllers, the velocity feedback was implemented into the embedded controller for controlling the position of the ball on the beam.The velocity feedback controller was implemented as a C program executed by a Freescale MC9S12C microcontroller.Second, it is a complete embedded control system that includes all the typical components such as sensors, actuators, signal conditioning circuits, and control methods.The sensors used in this system were infrared distance sensors.The actuator was a servomotor controlled by a pulsewidth modulated signal.The signal conditioning circuits were implemented with op amps for interfacing the sensor signals into the microcontroller.The control method used was velocity feedback.Third, this embedded system is inexpensive and mechanically simple for construction.This system has been used for demonstrating the applications of feedback control techniques.