A robust fuzzy PD controller for automatic steering control of autonomous vehicles

In this paper, we design an intelligent and robust stable fuzzy proportional-derivative (PD) controller for lateral control of passenger cars. An additional lateral displacement sensor is added at the tail bumper instead of gyro sensor in order to measure the yaw rate. First, a genetic-algorithm (GA)-based fuzzy PD controller is proposed to combine heuristics and optimization. Then, the fuzzy control system is transformed into a Lur´e system with uncertainties. The Lyapunov´s direct method is used to guarantee the stability of the perturbed Lur´e system, and then a robustness measurement that gives the bound of the uncertainties is derived. The performance of the proposed controller is compared with a conventional PD controller through simulation studies. Experimental studies on a small-scale vehicle are also reported.