INTEGRATED CONTROL OF ACTIVE REAR WHEEL STEERING AND DIRECT YAW MOMENT CONTROL

An integrated control system of active rear wheel steering (4WS) and d irect yaw moment control (DYC) is presented in this paper. Because of the tire nonlinearity that is mainly due to the saturation of cornerin g forces, vehicle handling performance is improved but limited to a ce rtain extent only by steering control. Direct yaw moment control using braking and/or driving forces is effective not only in linear but als o nonlinear ranges of tire friction circle. The proposed control syste m is a model matching controller which makes the vehicle follow the de sired dynamic model by the state feedback of both yaw rate and side sl ip angle. Various computer simulations are carried out and show that v ehicle handling performance is much improved by the integrated control system.