为提高智能汽车自动制动系统的性能及可靠性,设计基于传统液压制动系统的并联式电控液压主动防碰撞自动制动系统,针对整车动力学系统存在的参数摄动、外界干扰较强的非线性时变特征,提出μ控制策略控制制动管路压力,并进行参数摄动及外界干扰影响下的控制器性能仿真及整车道路试验。结果表明,采用μ控制算法的电控液压制动系统,在整车质量增加30%和制动盘-摩擦片摩擦因数减少30%两种工况下,整车期望加速度的稳态误差均控制在5%以内,稳定时间分别为1.7 s和1.4 s。
In order to improve the performance and reliability of intelligent automatic braking system and the braking performance of traditional hydraulic braking system, on the basis of active collision avoidance system, a parallel electro-hydraulic anti-collision automatic braking system was designed based on the traditional hydraulic braking system, its mathematical model in the state of supercharging and decompression was also established. In view of the parameter perturbation and non-linear time-varying characteristics of vehicle dynamics, and also considered the vehicle in the process of vehicle quality changes and brake disc-brake pads friction coefficient changes, the μ control strategy was proposed to control the brake line pressure, an electronic control hydraulic brake controller based on μ. control strategy and controller performance indicators were designed to simulate the performance of the controller under the influence of parameters perturbation and external disturbance, and the μ control strategy was compared with the H∞ control strategy. The results showed that the electronic control hydraulic braking system with μ control algorithm can control the steady-state errors of expected accelerations of the whole vehicle within 5% under the conditions of 30% increase in the mass of the whole vehicle and 30% decrease in the friction coefficient of the brake disc - friction disc. The stabilization time was 1.7 s and 1.4 s, respectively, indicating the accuracy of the model was high, which solved the influence of parameter perturbation and sensor noise on the performance of controller in the electronic control hydraulic braking system.