摘要
文中所研究的汽车动态控制系统是基于模糊逻辑控制的主动前轮转向(AFS)和直接横摆力矩控制(DYC)的集成。控制系统采用分层控制。上层使用模糊逻辑控制器(横摆角速度控制器),输入为横摆角速度偏差及其变化率,其输出为直接横摆力矩控制信号和前轮修正转向角;下层(模糊集成控制器)设计了基于轮胎侧向力工作区的模糊逻辑控制器,通过调整前轮侧向力的方向,激活切换函数来调节模糊逻辑控制器的比例因子。仿真结果表明,使用非线性七自由度车辆模型,与单独的AFS或DYC控制器相比较,使用集成AFS/DYC控制系统,汽车操纵稳定性得到了很大的改善。
An integrated vehicle dynamics control system is developed in this paper by a combination of active front steering（AFS） and direct yaw-moment control（DYC） based on fuzzy logic control. The control system has a hierarchical structure consisting of two layers. A fuzzy logic controller is used in the upper layer （yaw rate controller） to keep the yaw rate in its desired value. The yaw rate error and its rate of change are applied to the upper controlling layer as inputs, where the direct yaw moment control signal and the steering angle correction of the front wheels are the outputs. In the lower layer （fuzzy integrator）, a fuzzy logic controller is designed based on the working region of the lateral tire forces. Depending on the directions of the lateral forces at the front wheels, a switching function is activated to adjust the scaling factor of the fuzzy logic controller. Using a nonlinear seven degrees of freedom vehicle model, the simulation results illustrate considerable improvements which are achieved in vehicle handling through the integrated AFS/DYC control system in comparison with the individual AFS or DYC controllers.
出处
《机械工程师》
2009年第12期62-65,共4页
Mechanical Engineer
