Research On Robustness Of Intelligent Vehicle Longitudinal Active Collision Avoidance System Based On Equivalent External Interference Model

Under the complex dynamic environment,the rate of fatal traffic accidents caused by sudden risks such as pedestrians crossing the road in violation of regulations,and goods falling in front of the vehicle has remained high.For the intelligent vehicle driving assistance system,risk factors such as illegal pedestrians and falling goods will bring great challenges to the safe driving of intelligent vehicles.Therefore,it is of great significance for driving safety to study the robust control algorithm design of the active collision avoidance braking system of the intelligent vehicle under the risk of sudden emergency conditions.In response to this problem,this paper considers to propose an equivalent external interference model to quantify the accident risk caused by the sudden intrusion of pedestrians/goods.And it takes the sudden emergency working condition disturbance under the complex dynamic environment as indirect disturbance and takes the self-vehicle parameter perturbation and uncertain model error as direct disturbance,and constructs the controlled object model of the active collision avoidance braking system under the influence of multi-source perturbation/interference.Then,the paper bases on the μ control theory method designs a high-performance robust braking controller that meets the requirements of the vehicle control system under the risk of emergency conditions.The controller can effectively suppress the indirect disturbance effect of the accident risk under emergency conditions on the system and the direct disturbance effect of parameter perturbation and external disturbance on the controlled system,and has strong robustness.First of all,on the basis of the existing research results of the active collision avoidance braking system,taking into account the indirect disturbance effect of sudden emergency conditions brought by the complex dynamic environment on the system,the direct disturbance effect of vehicle parameter perturbation and external disturbance on the system during the actual driving process,a high-performance robust active collision avoidance lower control system scheme meeting the requirements of the vehicle control system under the risk of emergency conditions is designed.Afterwards,aiming at the accident risk characteristics of sudden emergency conditions in complex dynamic environment,an equivalent idea is proposed.Based on the analysis of the risk characteristics of emergency accidents,an equivalent virtual external force interference model is established to quantify the accident risk caused by the sudden intrusion of pedestrians/goods,and the simulation verifies the rationality of the design model,providing reliable guarantee for further blocking the risk of sudden traffic accidents.Then,simplify the nonlinear components based on the actual vehicle parameters of a certain intelligent vehicle testing platform,this paper considers the influence of parameter perturbation and uncertain model error on the system during the actual driving process,establishes the longitudinal dynamic model of active collision avoidance braking system.Then,it integrates the indirect disturbance effect caused by sudden accident risk under emergency working conditions,and establishes the controlled object model set of active collision avoidance braking system under the influence of multi-source perturbation/interference,and prepares for the design of the lower robust controller of the active collision avoidance braking system under the risk of emergency conditions.And then,taking the braking system of longitudinal dynamics perturbation model as the control object,combining the indirect disturbance effect brought by the emergency working condition and the direct disturbance effect of the external disturbance caused by the parameter perturbation in the actual driving process.Then,the lower brake controller of active collision avoidance is designed by the μ control theory.In the robust control toolbox of Matlab,the μ controller is solved and typical sudden emergency scenarios is simulated and analyzed,and the μ controller is compared with the nominal H∞ controller by simulation.The results indicate that the designed robustness μ braking controller can maintain a fast response speed and high robustness performance of the system in the presence of multi-source perturbation/disturbance,so that the system has excellent control effect.Finally,an HIL loop simulation test platform is built to further validate the effectiveness of the designed robustness μ braking controller,and the control model of the collision avoidance system is loaded into the NI real-time simulator,and the designed μ control algorithm is written into the vehicle controller,and the HIL simulation test is performed under typical emergency conditions.The results show that the designed longitudinal active collision avoidance μ controller based on equivalent external interference model has strong robustness in the application process of actual emergency scenarios,which provides a certain reference for better reducing the traffic accident rate under the sudden emergency risk of intelligent vehicles in the future.