Fuzzy Gain Scheduling PID Control Design Based on Particle Swarm Optimization Method

In this paper, a modified fuzzy gain scheduling PID controller via particle swarm optimization (PSO) method has been investigated. Unlike traditional try and error method or other tuning methods, some important tunable variables of proposed controller are determined by PSO method, i.e., the boundary and slope of membership functions. The gain margin and oscillation frequency determined by traditional Ziegler-Nichols method are modified by proposed PSO method in the same time to improve the output performance of controlled system. Several ship handling examples are provided, namely, course keeping and course changing, to demonstrate the advantages of the proposed method.