Parameter Identification Of Magic Formula Of Tire Based On Initial Value Optimization

Tire dynamics model is the key input parameter of vehicle simulation.As an important model of vehicle handling and stability simulation,Pacejka tire model has become an important input parameter of Adams,Car Sim and other international mainstream vehicle dynamics simulation software.At present,the domestic tire industry began to pay more and more attention to the tire six component test.How to get the tire Pacejka tire model parameters correctly and efficiently has become the focus of tire dynamics research in the tire industry.For this reason,according to the indoor tire parameter format identified by ADAMS software,this paper uses MATLAB optimization toolbox to complete the identification of the parameters of the latest pac2002 steady-state tire magic formula.The specific research work includes:1st.The principle of magic formula and the physical meaning of parameters are produced in detail,which provides theoretical guidance for the subsequent initial value optimization2nd.The second level identification principle is adopted for the parameter identification of magic formula of tire under pure longitudinal sliding condition and pure side deflection condition.The first level parameter optimizes the initial value of parameter identification according to the physical meaning of the basic form of magic formula of tire,and the first level parameter identification is completed by the trust region reflection method.The second-order parameters are identified by analytic method.3rd.The parameters of magic formula of tire lateral force are difficult to determine because of the physical meaning of the parameters.The genetic algorithm is used to determine the approximate initial value of the parameters,and then the trust region reflection method is used to further optimize and complete the final identification of the secondary parameters.4th.The identification method is verified by the actual test tire.The RSQ of the identification result curve and the test curve can be guaranteed to be more than 0.94.For the test condition of non tire identification,the RSQ of the theoretical calculation curve and the test curve is also more than 0.95.