H/sup /spl infin// controller design for automatic steering of vehicles with modeled time delays

An H/sup /spl infin// controller is designed for automatic steering of vehicles. In this study the main objective is to keep the vehicle´s center of gravity close to the center of the lane despite small variations in the speed of the vehicle. A generic sensor/actuator pair is assumed for the vehicle: the measured output is the offset signal at a look-ahead point, and the control input is the steering angle generated by a typical motor. Due to software limitations there exists a fixed time delay in the actuator model of this system. The H/sup /spl infin// controller is designed using Youla parameterization, coprime and inner/outer factorizations, and the Nevanlinna-Pick interpolation technique. The performance of this controller is tested by simulating the feedback system under several different road conditions.