Research On Automobile Active Braking/Steering For Obstacle Avoidance Control System

Vehicle active braking/steering for obstacle avoidance system is a vehicle active safety control system,which can detect whether there is any possibility of collision in the surrounding environment during vehicle driving.When the system make a judgement that the car may be a collision with an obstacle,first by voice or vibration remind the driver,if the driver still did not carry out any operation,then the system will automatically according to the traffic environment select active braking or initiative lane change,so as to ensure the safety of vehicle.This paper on the research of the automobile active braking/steering system,the first in-depth analysis of the safety status of automobile in the running process,then the automobile safety state model has been established according to the vehicle dynamics model;at the same time,taking into account the car in different traffic environment the best obstacle avoidance method should be different,so established considering the road traffic environment of the automotive active braking/steering obstacle avoidance switching strategy.Then the vehicle active brake obstacle avoidance system and the active lane change system are studied.To the automobile active braking avoidance system,considering the different road friction coefficient has an important effect on judgment of the safety state of the car,so based on the analysis of braking process and characteristics of tires,establish recursive least squares road friction coefficient identification algorithm.Then,in the process of calculating vehicle active braking pressure,we establish the calculation of the upper ideal longitudinal deceleration based on the LQR(linear quadratic regulator)algorithm and the expected braking pressure based on vehicle longitudinal dynamics.The initiative lane change avoidance system,through the research on the vehicle lane change process,using a method based on ideal lateral acceleration of path planning method and dynamic correction of steady state prediction of tracking,then through the simulation verified the proposed vehicle active steering/braking effectiveness of obstacle avoidance strategy.Finally,carrying out the automobile active braking/steering obstacle avoidance hardware in the loop,the result further validation of the proposed vehicle active braking /steering obstacle avoidance strategy is effective,and based on the laboratory experiment car platform,tested the vehicle active steering/braking for obstacle avoidance,vehicle test results show that the proposed automobile active braking/steering effectiveness of obstacle avoidance control system.