Research On Vehicle Longitudinal Collision Avoidance System Based On V2V Information Interaction

As one of the active safety technologies,the active collision avoidance system of the vehicle can reduce the fatigue strength of the driver,reduce the traffic accident rate and property loss,and is of great significance for improving traffic safety and improving the traffic environment.With the transformation of intelligent transportation systems from information service applications to traffic safety and transportation efficiency applications,and the development of intelligent connected vehicle collaborative service applications,single intelligent vehicle collision avoidance warning systems are flawed.This paper designs a vehicle longitudinal collision avoidance system based on V2 V information interaction to achieve the synergy between vehicle,road and environment,to alleviate traffic environment congestion,improve road environment safety and optimize system resources.The control structure,function definition and technical difficulties of the longitudinal collision avoidance system are analyzed,and the hierarchical control structure and decision mechanism are designed.The proposed collision avoidance warning control strategy uses DSRC as the way of vehicle travel information interaction.The safety distance model is used as the upper controller to calculate the expected acceleration value of the vehicle.The PID algorithm is used as the lower controller tracking the expected acceleration.The inverse dynamics model of vehicles,engine MAP and nonlinear control synthesis technology are used to calculate the real-time throttle opening or the brake pressure input required to set the acceleration value,thereby realizing the longitudinal control of the vehicle.Due to the nonlinear dynamic characteristics of the vehicle,in order to accurately describe the vehicle motion,the vehicle dynamics model is established by CarSim.Based on the longitudinal dynamic model data,an inverse dynamic model for calculating the desired throttle valve and the desired brake pressure,and a throttle and braking force control switching strategy based on the acceleration threshold are established in Simulink.The safety distance model is designed by analyzing the longitudinal collision timing and braking process.The DSRC sensor model and virtual test scenarios were built using the PreScan simulation test software,and build drivers in the loop test platform.According to the different functional requirements of vehicle longitudinal control,the paper respectively designed adaptive cruise and emergency collision avoidance upper controllers.Based on the hardware in the loop platform,multiple sets of offlinesimulation experiments are performed on typical working conditions.Experimental results show that the controller has good steady-state tracking and emergency collision avoidance effects,and the system dynamic response is rapid,which can achieve the expected function of following and collision avoidance.