HIERARCHICAL FUZZY PID CONTROLLER USING GRANULAR COMPUTING FOR INVERTED PENDULUM

The inverted pendulum (IP) is among the most difficult systems to control in the field of control engineering. The process is non linear and unstable. The objective of this paper is to balance the pendulum vertically on a motor driven wagon by the use of hierarchical fuzzy PID controller. The hierarchical fuzzy PID controller divides the control system into multiple granular levels and adopts different control strategies in different granularities. We use different fuzzy controls forcoarse adjustment in the coarse granularity and adopt classical PID as fine control in the fine granularity. Then we design asupervisor which is a fuzzy controller to switch between the different fuzzy controllers and PID control smoothly