Research On Active Collision Avoidance System And Hardware-in-the-loop Test

With the rapid development of the automobile industry and the increasing number of cars,and it has brought great convenience to people,but it also brings many hidden dangers.Among the dangers,the rear end accident is a more common traffic event,causing people to different degrees of loss,and in the rear end accident,a large part of them are due to the driver's failure to complete the collision avoidance measures in the effective time.The passive measures such as the airbag can not solve the problem from the root cause,so it belongs to the advanced driving assistance.The active collision avoidance control system in the system emerges as the times require to reduce the collision loss,including the longitudinal active collision avoidance and the lateral active collision avoidance.The longitudinal main performance is the braking,and the lateral main performance is the steering.In this paper,the longitudinal active collision avoidance control system is designed based on the sliding rate of each wheel,and the longitudinal distance is used as the evaluation index.The longitudinal controller is designed based on the fuzzy sliding mode algorithm.The appropriate braking time is selected by the longitudinal risk assessment model,and the slip rate of each wheel is kept near the expected slip rate.In the process of emergency collision avoidance,the vehicle can obtain maximum braking speed and avoid collision in the shortest braking distance.The lateral collision avoidance control system is designed with the lateral displacement of the car as the control target and the side angle of the centroid angle as the evaluation index.The lateral controller is designed based on the Preview PID algorithm,and the lateral risk assessment model is adopted.The proper steering time is selected to make the vehicle track the desired Collision Avoidance Trajectory and avoid collision along the optimal path in the emergency collision avoidance process.The whole vehicle dynamics simulation model is built based on Car Sim software,and the control simulation model is built based on MATLAB/Simulink software,and the control effect of the active collision avoidance control system is verified by the joint simulation.In the experiment,the braking control system platform is designed on the base of a passenger car brake,the electric cylinder and the plunger pump are the main turbocharging source,the solenoid valve is the main control mode,and the steering control system is designed on the base of a passenger car steering gear,and the steering angle of the steering wheel is the main control target.Based on PXI and d SPACE hardware,and Lab VIEW and Simulink software,the hardware in the loop test platform is built,and the CAN bus is used as the main communication carrier.The brake pressure test is carried out on the brake test bench and the hardware in the loop test is carried out on the steering test bench.Finally,the feasibility of the longitudinal active collision avoidance control system is verified by the joint simulation.The simulation results show that the longitudinal active collision avoidance control system can have good control effect on the vehicle longitudinal braking distance in an emergency.The feasibility of the lateral active collision avoidance controller is verified by the joint simulation and the hardware in the loop test.The experimental results show that the lateral collision avoidance controller can not only simulate,but also perform collision avoidance tasks well when controlling real actuators.