Application of optimum tire force distribution to vehicle motion control

This paper presents a motion control scheme for a front-wheel-steering/rear-wheel-driving (FWS/RWD) vehicle using the optimum tire force distribution method. The proposed control system is divided into three layers: the upper controller, the optimum tire force distribution algorithm, and the lower controller. When the driver commands the vehicle, the upper controller computes the total desired longitudinal tire force, lateral tire force, and the desired yaw moment which allow the vehicle to follow the given reference trajectory. Then the desired forces and moments are optimally distributed to the four wheels, and the lower controller compensates for the nonlinear and uncertain characteristics of the tire dynamics to generate the desired forces. Finally, simulations are carried out to verify the effectiveness of the proposed control scheme.