The Study Of Real-time Detection Method Based On Thermo-dynamic Coupling Analysis Of The Vehicle Braking Force

Brake disc is one of the important components of the vehicle braking system,and the key equipment for driver’s driving safety.Brake disc can not only provide vehicle braking force,at the same time can also provide technical support for the various brake assist system,the self-driving technology also has a strong dependence for the detection of braking force.In existence,the brake force detection technology has rigorous limits to the speed of vehicle and the detection ground condition.And these methods can only detect vehicles ’ total braking force,but cannot accurately measure the size of the braking force on brake disc,even can’t detect the actual working state of the brake disc.On the one hand,the driver can’t get the information of the vehicle brake system’ working state at any time,it will increase the risks of driving;on the other hand other braking assist system will not get the accurate data support provided by braking system.Aiming at the shortcomings of the brake force detection technology,we design a algorithm,which made the temperature difference between contact surface and disk inside surface as input value,by studying of the thermal-mechanical coupling analysis of brake disc.In this paper,the main research contents and innovations are as following:(1)Based on research on the principle of heat transfer and mechanics,the brake disc thermal-mechanical coupling characters are analyzed by using finite element method,and the brake disc’s thermal stress numerical model is established.(2)The relationship between the friction coefficient,brake disk,tensile strength,elastic modulus and temperature is analyzed,and written as an experience equation.The relationship between press force,rotate speed,friction coefficient and temperature difference is also analyzed.As a result,the brake force detection algorithm is established.(3)Model for a certain type of vehicle brake disc,the three-dimensional model is established in Ansys,in the thermal-mechanical coupling analysis,it is concluded that the brake disc surface stress and the influence of the structure is very obvious effected by temperature,and the trend is consistent with the theoretical analysis.The simulation data is also used to provide to support the algorithm fitting and the early stage of the data validation.(4)According to the analysis method of algorithm design,numerical simulation and the validation process.Based on the simulation data,the accuracy and feasibility of braking force detection algorithm are analyzed,and learned that the algorithm designed meet the requirements of braking conditions.In this paper,aiming at the shortcomings of the vehicle braking detection system,a new kind of braking force detection algorithm is designed,which realize the real-time detection of the braking force by analyzing thermal-mechanical coupling characteristics of the brake disc under the premise that does not destroy the structure.The study can not only strengthen the protection of drivers’ life and property security,promote the development of vehicle braking detection research,at the same time can also establish a new standard for the braking force detection industry,but also it can give the brake disc industry a new development direction,also provide a great reference value for the development of the braking force detection technology.