对带有线控制动系统(brake by wire,BBW)的车辆进行研究,提出了一种横摆稳定性优化控制策略.以二自由度单轨车辆模型为参考模型,利用比例一积分(proportionalintegral,PI)控制算法求出附加横摆力矩.由所计算出的车辆附加横摆力矩、方向盘转角来识别驾驶员转向意图和车辆实际行驶特性,通过广义逆法和数学归划法相结合的方法将附加横摆力矩分配到作用车轮上,由线控制动系统采用主缸定频调压法对各轮缸的目标液压力进行跟踪控制.硬件在环试验结果表明,该控制策略能够有效地保证车辆在高附和低附路面工况下的横摆稳定性.
Based on vehicle with brake by wire system (BBW), this paper proposed a new yaw stability optimized control strategy. Two degrees of freedom vehicle model was used as reference model, and proportional integral (PI) control algorithm was used to derive the additional yaw moment. According to the additional yaw moment and the steering wheel angle, the driver's intention and the actual driving characteristics of vehicle were recognized. This paper distributed the additional yaw moment to every wheel based on the method combining the Pseudo Inverse method and mathematical programming approach. Within brake by wire system, the master cylinder fixed frequency pressureregulating method was used to follow the target wheel cylinder pressure. The results of hardware-in-loop (HIL) test show that this control strategy can ensure the yaw stability of vehicle effectively on the road surface with high or low adhesion coefficient.