Study On Vehicle Driving Safety Control Oc Ice Road

Ice easily occurs on road pavement which is in southwest mountainous areas and wet areas in the south of China.The ice layer on pavement completely shields the antisliding structure.So,tires contact with the ice directly and the road pavement adhesion coefficient is drastically reduced.Cars are prone to lateral instability on icing roads,and the braking distance is greatly increased.At present,the research on the lateral stability control of vehicle mainly considers generally low-adherent roads such as wet skis and snow,and there are few considerations for the icing conditions;There is also a lack of research on the road alignment design for icing road safety.In view of the horizontal and vertical safety of cars driving on icing roads,this paper which relies on the National Natural Science Foundation of China(51408446)"skid-resisting characteristics of asphalt pavement with glazing ice by considering complex contacting effect between tire and pavement",studies the lateral stability control of the car and the stopping sight distance design of the curve section on icing road respectively and combining vehicle control and route design to ensure the safety of car ice driving.Firstly,the generation and deicing methods of road condensing ice were introduced by this paper.According to the experimental and semi-empirical tire models,the adhesion coefficient of the smooth ice surface during freezing is obtained.Aiming at the ultra-low adhesion characteristics of icing road,a lateral stability controller based on direct yaw moment control strategy and sliding mode control is designed with yaw rate as the target variable;the controller adopts unilateral two-wheel braking.To obtain a larger additional yaw moment on the ice,and to design the braking force distribution based on the constraints of the ice attached to the ellipse.The controller uses a singlesided two-wheel brake to obtain a larger additional yaw moment on the ice surface,and a brake force distribution is designed based on the limit of the attached ice ellipse.Vehicle simulation model is established in Matlab/Simulink to verify the control effect of the lateral stability controller under two kinds of steering limit conditions.The simulation results show that the uncontrollable car will lose stability when the car turns on icing road at low speeds;The designed lateral stability controller has better control effect on steering stability and maneuverability of the car under ice conditions;Vehicles equipped with controllers may still be unstable under the extremely dangerous conditions of high-speed obstacle avoidance.Based on the calculation of stopping sight distance for the straight road,a stopping sight distance calculation method for curved road was proposed,and validates the correctness of the calculation model through CarSim's braking simulation test.According to the curve stopping sight distance calculation method,the stopping sight distance of the icing road section with different parameters of the circular curve is given as a reference;According to the road linear design specification,it is used to calculate the safe traffic speed of the curved road when occurs on road.