四轮转向车辆后轮转角与横摆力矩联合模糊控制

为提高车辆在极限工况下的稳定性,充分考虑悬架、转向系统以及轮胎等部件的非线性,运用多体动力学仿真分析软件ADAMS/Car建立了四轮转向车辆的虚拟样机模型.确定了质心侧偏角和横摆角速度具有理想输出响应的控制目标.针对车辆的非线性,提出了后轮转角与横摆力矩联合控制的模糊控制策略,并设计了对应的非线性模糊控制系统.最后应用ADAMS/Car和Matlab/Simulink联合仿真技术,对控制系统的性能进行了仿真验证.仿真结果表明:后轮转角与横摆力矩联合模糊控制可有效防止车辆在极限转向工况下发生侧滑失稳.

Yaw Moment Fuzzy Control of Four-wheel-steering Vehicle Based on Co-simulation Technology

In order to enhance the stability of vehicle in limited driving conditions, a virtual prototype model of four-wheel-steering vehicle which included suspension system, steering system and nonlinear characteristics of tires was established by using ADAMS/Car software. Control objectives of the best performance of side slip angle and yaw rate were settled. Aiming at the nonlinear characteristics of vehicle, an integrated fuzzy control strategy of rear steering angle and yaw moment was proposed, and a nonlinear integrated fuzzy control system was designed. Adopted the co-simulation method of ADAMS/Car and Matlab/Simulink, various simulations in limited driving conditions were carried out and the performance of the designed control system was tested. The simulation results showed that the integrated fuzzy control of rear steering angle and yaw moment could effectively avoid the instability of vehicle during critical steering process.