Inverted Pendulum Swing Up Controller

The inverted pendulum is a classic control problem. The system is open – loop unstable and continuously wants to reach equilibrium by falling over. The system must be stabilised by means of feedback. The developed inverted pendulum system is shown in Figure 1. In order to balance the pendulum in the inverted position the pivot must be moved continuously to correct the falling pendulum. This is similar to trying to vertically balance a broom on your hand. This interesting control problem is fundamentally the same as those involved in rocket or missile propulsion. The rocket has to balance on its engine as it accelerates. As the rocket tends to fall over, the rocket thrust must be deflected sideways to restore the rockets course. This is just one of many practical applications of the system. This paper describes the technology introduced to achieve this design and development which is now a working piece of demonstration kit for control and mechatronic engineering.