摘要
针对汽车AFS转角特性和启动条件存在的问题,通过建立二自由度汽车动力学模型,推导出基于整车参数、车速和车轮转角的汽车转弯半径。结合汽车安全视距,建立汽车转向时的AFS数学模型,得到汽车前照灯调整角度计算公式。根据车灯等照度包络曲线推导出汽车AFS启动条件,得到AFS启动条件的控制模型,并验证了AFS启动条件设定的合理性。采用模糊PID控制策略,通过Matlab/Simulink对转角特性和启动条件进行了建模仿真分析。仿真结果表明,优化后的转角特性和AFS启动模型能准确地确定AFS开启的时刻,避免了AFS提前或滞后开启的问题,提高了汽车夜间行驶的安全性。
Aiming at the problems lies in the turning angle characteristic of the automobile AFS and the starting condition, the turning radius of the the car based on the whole vehicle parameters, the vehicle speed and the turning angle of wheel can be calculated through building a two -freedom vehicle dynamic model. Combined with automobile safety sight distance and the es- tablishing of the mathematical AFS model of the vehicle, the calculating formula of the vehicle headlight adjusting angle can be obtained. According to the illuminanee envelope curve of the ear lights ete, the AFS start - up condition is derived, the control model of AFS is obtained, and the rationality of the setting of the AFS start - up condition is verified. Besides, the fuzzy PID control strategy is adopted, and the simulation analysis of the turning angle characteristic as well as the starting condition is car- ried out by the MATLAB/Simulink. The simulation results show that the optimized angle characteristic and the AFS start - up model can accurately determine the starting time of AFS, which can avoid the problem of in advance or delay of the starting time, therefore improve the safety of the car driving at night.
出处
《武汉理工大学学报（信息与管理工程版）》
CAS
2016年第2期257-262,共6页
Journal of Wuhan University of Technology：Information & Management Engineering
基金
武汉理工大学-福瑞特校企合作资金项目(20132h0080)
