Ball and Beam Balance Using PID Control

www.wilselby.com for more information Tom Trapp and Wil Selby Department of Mechanical Engineering Massachusetts Institute of Technology 2.151 Advanced System Dynamics & Control Fall 2009 Abstract The primary objective of this project was to create a control system that could effectively balance a ball on a metal beam using a motor input to control the angle of the beam. This project covered the full scope of design including creating a valid model of the system, identifying numerical values for the model parameters, designing an effective control system, assembling the system hardware, and implementing the control system using a microcontroller to interface with the motor. The ball and beam balance problem is a classic open loop unstable system. For a constant input there is a non-constant output. In this system, a constant beam angle causes the ball to accelerate due to the force of gravity and the ball's position increases non-linearly. Investigating this system resulted in numerous insights of control design that can be applied to multiple applications. Utilizing full state feedback, the controller was able to repeatedly and effectively balance the ball at the given desired reference point with reasonable transient performance. In the future, the addition of a Kalman filter for state estimation and a LQR based controller could make the system even more effective.