Abstract:

Aiming at the steering angle allocation of distributed independent steering system,first,the structure and operation principle of distributed steering system are expounded.Next,based on the Ackermann steering principle,a steering angle allocation algorithm suitable for both front-wheel steering ( 2WIS) and four-wheel independent steering ( 4WIS) is put forward with the consideration of the front tier cornering,and the optimization effect of the proposed algorithm on the tire wear and the vehicle stability is investigated.Then,by using a linear vehicle model with two degrees of freedom,the relationship between tire sideslip angle and vehicle speed,yaw rate as well as wheel angle is explored,and the Ackermann steering principle is modified with the obtained tire sideslip angle,which helps to reveal the steering angle allocation of each wheel.Finally,a Carsim-Simulink combined simulation is performed to verify the correctness of the proposed steering angle allocation,the improvement in tire wear pattern is determined by evaluating the optimized tire lateral force,and the vehicle stability is evaluated by using the sideslip angle.Simulated results indicate that the proposed steering angle allocation method is effective in improving the tire wear and enhancing the vehicle stability.

Key words: distributed independent steering system, Ackermann steering principle, steering angle allocation, sideslip angle, tire wear, vehicle stability