The Research On Vehicle Longitudinal Safety Control Strategy Considering Human-Machine Communication Characteristics

With the improvement of material and living standards,people’s demand for automobiles has increased,and the number of cars has increased.However,the traffic accidents caused by this are also very serious.Among them,traffic accidents caused by rear-end collisions are the most common,so it has become a research topic of many companies and universities.As the intelligent driving assistance technology,forward collision warning and automatic emergency braking can help drivers reduce or even avoid traffic accidents,thus becomes an important protection technology for driving safety.Based on a large number of researches on the status quo of research at home and abroad,this paper conducts an in-depth study on the longitudinal safety control strategy of automobiles for the current development trend of safe driving in the automobile industry.At first,this paper sets up the vehicle dynamics and the safety distance model.The establishment of the vehicle dynamics model includes the establishment of vehicle longitudinal dynamics model and inverse longitudinal dynamics model.The longitudinal dynamics model of the vehicle is established in CarSim,and the inverse longitudinal dynamics model of the vehicle is established in Simulink.The overall dynamic simulation model of the vehicle is carried out by setting the input and output between the joint simulation software interfaces.The driving safety distance model is established on the basis of the safety distance model based on the braking process.By considering the different operating conditions of the preceding vehicle and different driving styles,the two-level safety warning distance model is established to meet the warning needs of different driving styles,and the two-stage braking safety distance model is set up to ensure driving safety in an emergency.Then this paper studies the longitudinal safety control strategy of automobiles and carries out the real vehicle experiment of forward collision warning.And it determines the control functions to be implemented by the system,and designs the control system through a layered control method.The underlying control of the desired acceleration is realized by the PID design of the lower controller.The optimal control is selected for the design of the upper controller to obtain the desired acceleration.At the same time,by considering the characteristics of humanmachine communication,the research on the specific two-level warning and two-level braking control strategies are carried out.And according to the existing conditions,the real vehicle experiment platform is built to carry out the real vehicle test of the forward collision warning function.The paper introduces the equipment used in the test,test plan and location.And it describes the identification method of the effective target vehicle in front and uses the real vehicle test to verify the usability of the identification method.At the same time,the real vehicle collision warning test is carried out when the vehicle ahead is in the static state and the uniform motion state,which proves the effectiveness of the collision warning control strategy.Finally,the joint simulation model is built to analyze the warning and braking functions under typical conditions to illustrates the effectiveness and rationality of the vehicle longitudinal safety control strategy.And the control effects of the safety distance model before and after the improvement are compared to show the effectiveness of the driving safety distance model.The results of real vehicle test and simulation are compared to verify the rationality of the collision warning control strategies.The results show that the vehicle longitudinal safety control strategy considering human-machine communication characteristics can better realize the collision safety warning of the vehicle and ensure the safety of the driving process.