Research On Steering Braking Combined Collision Avoidance Control Of Intelligent Vehicle

With the rapid growth of automobile ownership,automobile safety accidents occur frequently.In order to improve the safety of road driving,automobile active safety technology came into being.Among them,the vehicle active safety obstacle avoidance control system senses the surrounding environment information,evaluates the collision risk through the sensors carried by the vehicle,and controls the vehicle to turn and brake independently,so as to ensure the driving safety of the vehicle.During the active safety obstacle avoidance control of intelligent vehicle,the motivation of lane change and braking is deeply analyzed,and the safety distance model considering the characteristics of driver is established to determine the safety conditions of vehicle emergency braking and lane change.At the same time,considering the location relationship between the vehicle and traffic barrier vehicles and the status information of the vehicle,the risk assessment index is designed to predict the future collision risk.On this basis,the vehicle active safety obstacle avoidance controller is designed based on the model predictive control method.Combined with vehicle dynamics constraints,traffic collision constraints and risk assessment indicators,the vehicle front wheel angle and acceleration are optimized,and the vehicle is controlled for steering braking joint collision avoidance.The effectiveness of the obstacle avoidance strategy is verified by Simulink and Car Sim joint simulation.In addition,in order to improve the tracking performance and driving stability of vehicle collision avoidance path under extreme conditions,a vehicle path tracking control method considering the tire reverse potential is designed based on model predictive control theory.Firstly,in order to reduce the collision avoidance discomfort and even vehicle instability caused by the sudden change of path curvature in the process of collision avoidance control,an S-function is used to plan a continuous and smooth collision avoidance path;Secondly,the equal backup potential index of tire longitudinal force and lateral force is constructed,the path tracking controller of steering braking combination is designed based on model predictive control to solve the constrained multi-objective optimization problem,which is verified by simulation experiments.In order to further verify the effectiveness and reliability of intelligent vehicle steering braking combined collision avoidance control in the actual scene,this paper establishes an intelligent vehicle experimental platform,and carries out actual vehicle experimental verification of the Ackerman steering experimental vehicle.The experimental results show that the proposed method is feasible and effective,and the intelligent vehicle can realize autonomous and safe obstacle avoidance through the joint control of steering and braking.