基于零力矩点位置和模糊控制的商用车防侧翻控制

Anti-Roll Control for Commercial Vehicles Based on Zero-moment Point Position and Fuzzy Control

为了防止车辆发生侧翻,引入零力矩点的位置作为车辆侧翻的指标。根据某一时刻车辆的状态,预测下一段时间内零力矩点的y坐标,来计算该时刻的侧翻时间。一旦某时刻的侧翻时间小于设定的门限值,则激活车辆防侧翻控制策略,对车辆进行控制,防止车辆发生侧翻。本文中采用基于模糊控制的PID控制策略,对不同的车轮施加不同制动力矩,防止车辆发生侧翻。通过Truck Sim和Matlab/Simulink联合仿真,对算法进行验证,对采取模糊控制差动制动策略、传统的PID策略和无侧翻控制策略的车辆,分别进行阶跃试验和鱼钩试验,测取采取不同控制策略车辆的实时侧倾角。对比结果表明,采用模糊差动制动控制策略的车辆,防侧翻性能最好。

In order to prevent the rollover of vehicle,the position of zero-moment point( ZMP) is introduced as an indicator of vehicle rollover. According to the state of vehicle at certain moment,the y coordinate of ZMP at next coming moment is predicted,with which time to rollover( TTR) is calculated. Once the TTR at certain moment is less than the preset threshold,the vehicle anti-rollover control strategy is activated to prevent the vehicle from rollover. In this paper,PID control strategy based on fuzzy control is adopted and different braking torques are applied to different wheels to prevent vehicle rollover. Through co-simulation of Truck Sim and Matlab/Simulink,the algorithm is verified. Specifically the step input test and fishhook test are conducted with differential braking fuzzy control strategy,traditional PID control strategy and no rollover control strategy respectively to measure the real time roll angle of vehicle with different control strategies. The results of comparison show that the vehicle with differential braking fuzzy control strategy has best anti-roll performance.