Control of Steer-by-Wire Vehicles with Passivity Approach

Abstract

Steer-by-wire system (SBW), in which the conventional mechanical linkages between the steering wheel and the front wheel are removed, is suited to active steering control, improving vehicle stability, dynamics and maneuverability. And SBW is applied to autonomous steering control to assist the driver. Conventional controller for SBW system is designed by general feedback control method. However, in this method, the driver cannot exactly feel the reaction torque generated from tire about road friction. And the stability of control system cannot guarantee in spite of highly variable human operators and environment dynamics. The goals of this paper are considered as follow: The one is a reproduction of environmental impedance in steering wheel. The other is the improved maneuverability for SBW system. Moreover, the stability of control system must be satisfied. This paper, first, reviews bilateral control scheme using disturbance observer proposed by us. Secondly, this paper proposes a novel bilateral control scheme with passive approach. We also examine the performance of the proposed control scheme and compare with bilateral control scheme using disturbance observer. The effectiveness of proposed method is demonstrated by experiment with electronic vehicle.