Research On The Control Algorithm Of Vehicle Collision Mitigation Braking System

With the rapid development of social economy,the automobile industry also ushered in the opportunity of rapid development,but traffic accidents have increased year by year,and traffic safety has become a worldwide problem.Therefore,in order to solve the severe traffic problems and reduce the number of casualties due to traffic accidents,vehicle active safety has become an important subject.Under the requirements of modern traffic safety,the passive safety of vehicles can no longer meet the requirements of people.On the basis of safety,the comfort of the driver should also be considered,that is,the humanization of the control system.Although the research on vehicle active collision avoidance has made great progress in recent years,there are still many areas that need further study.At present,vehicle collision avoidance controllers are mainly focused on longitudinal controllers,and there are relatively few studies on lateral lane change controllers.In collision avoidance control,vehicle safety is mainly considered,while human comfort and economy are ignored.In view of the above problems,this paper,funded by the national key scientific and technological research and development program "research and development and industrialization of intelligent assisted driving technology for electric vehicles",studies the control algorithm of vehicle collision mitigation braking system,mainly including the following aspects:(1)Accurate dynamics modeling was established for the vehicle collision avoidance system.With the help of the modeling function of Carsim,the vehicle inverse dynamics model was constructed to prepare for the research on longitudinal braking control and lateral lane change control of the vehicle behind.The desired throttle opening and the desired brake pressure are obtained by establishing the vehicle inverse dynamics model.This part is the basis of the design of the controller system and the realization of the function of collision avoidance control.(2)The longitudinal controller of the vehicle collision system is established.Firstly,the safety distance model under different circumstances is established through the acquisition of environmental information of the vehicle by the sensors in the vehicle to judge whether the vehicle is in a dangerous situation.Then using the method of hierarchical control,the upper acceleration model prediction controller and the lower single neuron PID control are established.Considering the safety of the vehicle,the driver’s comfort and economy.Finally,simulation experiments are carried out to verify the effectiveness of the vehicle collision avoidance longitudinal controller.(3)The vehicle collision avoidance system side lane change controller is established.When the distance between the vehicle and the front vehicle is less than the braking safety distance,and the braking cannot ensure the safety of the vehicle,side lane change is adopted.Steering control adopts model predictive control algorithm to constrain vehicle yaw velocity,lateral acceleration and centroid lateral Angle,which not only ensures vehicle safety,but also ensures vehicle comfort and stability.Finally,the effectiveness of vehicle lateral lane change control is verified by simulation experiment.