在分析汽车防抱死制动系统传统控制方法以及汽车稳定性控制系统集成控制基础上,提出了基于滑移率的模糊控制方法。利用Matlab的模糊工具箱建立了模糊控制系统;搭建了基于Simulink的7自由度车辆模型、Dugoff轮胎模型和压力调节单元模型;基于有限状态机理论的控制输出模型,在此模型搭建的环境中完成了单一路面和对接路面仿真。仿真结果表明:基于Matlab/Simulink/Stateflow的ABS仿真系统能很好的模拟车辆制动过程;基于滑移率的模糊控制方法能将滑移率稳定控制在理想值,为车辆稳定性系统集成控制提供了必要接口;能有效地缩短制动距离,提高车辆的方向稳定性,对路面的突变具有很好的适应性。
Through the analysis of traditional control algorithm of ABS (Antilock Braking System) and integral control of VDC (Vehicle Dynamics Control) and ABS, a fuzzy logic control strategy based on slip ratio was proposed. The proposed control algorithm was constructed by the fuzzy logic toolbox of Matlab; a 7 DOF (degree of freedom) vehicle model Dugoff tire model and hydraulic control unit model were built in Simulink; control output model was constructed based on FSM (Finite State Machine). Single adhesion characteristics and changing adhesion characteristics simulations were conducted in the environment based on the constructed model The simulation results show that the simulation system based on Matlab/ Simulink/Stateflow can greatly reflect the brake process; the proposed control algorithm can control the slip ratio to provided value, it can be an interface to integrate the VDC and ABS system; it can shorten the brake distance to keep steering stability and it has good adaptability to the changing adhesion characteristics.