Research On Rollover Warning System Of Wheeled Vehicles

With the rapid development of society and the improvement of road traffic facilities,the car is applied more and more widely in daily life,the number of vehicles increases rapidly.The vehicle safety requirements of people demanding are also increasing,but the problem of vehicle rollover is not been enough concerned.Therefore,designing a kind of economical and practical vehicle rollover warning system is very necessary to avoid the occurrence of vehicle rollover accident.Based on the above results and situations,this paper put forward a vehicle rollover warning scheme to solve the above problems.An electric car was selected as experiment platform,the hardware platform of the whole side turn warning system was built and the software system was written.The whole warning system was debugged and the related experiments are also be done with the experimental platform.The main research contents and conclusions are as follows:(1)This paper analyzes the current research and development situation of domestic and foreign vehicle rollover warning system and the rollover stability,the problems and challenges in the research and development of vehicle rollover warning system is put forward.The continuous acquisition vehicle related state parameters and calculating the lateral acceleration of the vehicle,and the vehicle rollover acceleration threshold comparison,in order to determine the equilibrium state of the vehicle,and according to the degree of risk early warning scheme of different audible alarm of the corresponding level.(2)According to the different types of rollover,this paper analyzed the cause and process of rollover.A rigid model of a vehicle as a physical model of vehicle rollover threshold is established.With detailed comparison and analysis of various evaluation indexes of rollover,this paper select the lateral acceleration as evaluation indicator for the vehicle rollover warning system.The vehicle balance equation under different conditions are analyzed,and it provides a theoretical basis for the vehicle rollover warning system.(3)An electric car is selected as experiment platform in this research.The sensor parts in this study include the speed sensor module,the steering angle sensor module and the side tilt angle sensor module to realize the real-time acquisition of vehicle status information.The required sensors are selected,installed and debugged,and the accuracy of each module is measured.The error of the vehicle angle sensor module is less than 5%,the error of the vehicle side tilt sensor module is less than 1%,and the vehicle speed sensor module error is less than 6%,which can meet the design requirements.In this study,the host computer selects PC and the lower computer selects 51 single chip computers.Completed the transformation of the experimental car,and built the entire hardware platform.(4)The software design in this study mainly includes PC software design and lower machine software design.The program of the lower computer is the program to measure the speed of the single chip microcomputer.In the integrated development environment of Keil uVision4 version,the program is written in the C language.The initial processing of the Holzer pulse of the Holzer sensor and the communication with the host computer are mainly taken into account.The upper computer program is written by the graphical programming software Lab VIEW.The program of the upper computer block diagram is mainly based on the rigid vehicle model,and the lateral acceleration of the vehicle is calculated by 3 kinds of data transmission.According to the comparison of the early warning range of the lateral acceleration of the vehicle,the risk degree of the side turn of the vehicle is judged,and according to the different risk degree.For the corresponding level of rollover early warning.(5)The overall debugging and related experiments of rollover warning system were carried out.When debugging the whole system,we debug each sensor module first,and confirm the power supply and connection of each module.Then the communication between each module and host computer is completed.And the running of the host computer software.The ultra realtime performance of the early warning system is verified.In the simulated vehicle driving,the critical vehicle speed and the critical vehicle steering angle are measured when the side tilt angle of the vehicle is 0,5,and 10,and the side turn warning system sends out the first-level,two-level,and three-level early warning.The overall error of the warning system is 8.04%.The experiment shows that the relevant parameters and accuracy of the rollover warning system are basically the same with the scheme design,so that the forewarning function of vehicle rollover can be realized.