Robust tracking and disturbance attenuation controllers for automatic steering

The problem of asymptotic robust output command tracking with simultaneous disturbance attenuation is studied for the case of linear systems with nonlinear uncertain structure. The problem is solved using a compensator with static state feedback, unity output feedback and integral action. The controller is restricted to be independent from the uncertainties. The output of the closed loop system tracks polynomial type reference signals independently from polynomial type disturbance signals. Sufficient conditions for the problem to have a solution are established. The results are applied to the automating steering of a city bus with large speed and mass uncertainties. An analytic algorithm for the computation of the vehicle tracking controller is presented. The effectiveness of the controller is illustrated through simulation for various manoeuvres.