Electric power steering with H-infinity control designed to obtain road information

"Optimum steering feel", one goal of an automotive engineer, is related to how much information a vehicle obtains relating to the road. "Road information" is regarded as a frequency band of tire/steering wheel transmission characteristics, and in this paper we propose a method of supplying road information to the driver using a systematic control design with a generalized plant and H/sup /spl infin// control. In addition, the suitability and effectiveness of this electric power steering (EPS) control system in supplying road information, derived from a greater freedom in designing the steering characteristics, is proven in experiments.