Fuzzy control of a ball-balancing system.doc

Fuzzy control of a ball-balancing system
Ⅰ. Introduction
The ball-balancing system consists of a cart with an arc made of two parallel pipes on which a steel ball rolls. The cart moves on a pair of tracks horizontally mounted on a heavy support (Fig. 1). The control objective is to balance the ball on the top of the arc and at the same time place the cart in a desired position. It is educational, because the laboratory rig is sufficiently slow for visual inspection of different control strategies and the mathematical model is plex to be challenging. It is a classical pendulum problem, like the ones used as a benchmark problem for fuzzy and controllers, as sales material for fuzzy design tools.
Initially, the cart is in the middle of the track and the ball is on the left side of the curved arc. A controller pulls the cart left to get the ball up near the middle, then the controller adjusts the cart position very carefully, without loosing the ball.
Fuzzy control provides a format methodology for representing, manipulating and implementing a human’s heuristic knowledge about how to control a system [1-3]. Here, the fuzzy control design method will be used to control the ball-balancing system.
Fig. 1 Ball-balancing laboratory rig
Ⅱ. Design objective
a). Learning the operating principle of the ball-balancing system;
b). Mastering the fuzzy control principle and design pro