Robust automatic steering control for look-down reference systems with front and rear sensors

This paper describes a robust control design for automatic steering of pass enger cars. Previous studies showed that reliable automatic driving at high way speed may not be achieved under practical conditions with look-down ref erence systems which use only one sensor at the front bumper to measure the lateral displacement of the vehicle from the lane reference. An additional lateral displacement sensor is added here at the tail bumper to solve the automatic steering control problem. The control design is performed stepwis e: First, an initial controller is determined using the parameter space app roach in an invariance plane. This controller is then refined to accommodat e practical constraints and finally optimized using the multiobjective opti mization program (MOPS). The performance and robustness of the final contro ller was verified experimentally at California PATH in a series of test run s.