Optimization Of Vehicle Handing And Stability Based On ADAMS

The economy continues to develop in China.It leads to the rapid development of the automotive industry and the rapid expansion of the automotive market share.With the increasing number of home car ownership,as well as the continuous speed of the vehicle,the safety and comfort of the vehicle becomes more and more important.Vehicle handling stability has a crucial impact on the safety and comfort of the car.The study of vehicle handling stability has become the focus of scholars'research.In the study of vehicle handling stability,the research on the minimum time handling stability of the vehicle is relatively few.In this paper,subjective evaluation index system of the minimum time handling stability and optimization of vehicle minimum time handling and stability are studied.(1)The subjective evaluation method of vehicle handing stability at home and abroad was analyzed and compared,based on fuzzy analytic hierarchy,the fuzzy hierarchy evaluation system of vehicle minimum time handing stability was established.According to the fuzzy analytic hierarchy,the triangular fuzzy number complementary judgment matrix was constructed,the probability matrix was calculated,the expert fuzzy evaluation matrix was constructed,the adjustment judgment matrix was calculated and transformed into the fuzzy complementary judgment matrix,and the weight coefficient of the evaluation index was calculated.According to the weight coefficient of each index,the subjective evaluation scores of each vehicle are calculated.The results show that the handing stability of the forth vehicle is the best.(2)According to the objective evaluation index of the minimum time handing stability,the dynamics model of 12 vehicles was analyzed through double lane change test by ADAMS/Car.The multiple linear relationship of the objective evaluation index and the minimum time handing stability subjective evaluation of the total score was established through the individual linear evaluation method.It can be seen from the regression results that the correlation coefficient R is 1,the coefficient R~2 is0.9999 and the F test is 1667.11.The results show that the objective evaluation index value and the subjective evaluation score have a reliable multiple linear relationship,they have a good consistency relationship(3)The basic principles,processes and methods of the experimental design were introduced,and the Insight optimization theory was briefly described.The suspension of sensitivity was analyzed by ADAMS/Insight through the four-wheel positioning parameters as the optimization target.The 10 influencing factors with large influence on suspension were found according to results and the 10 influencing factors were adjusted.The range of vehicle kingpin caster angle is reduced from 5.35°~5.60°to4.15°~4.35°,The range of vehicle kingpin angle is reduced from 9.0°~11.3°to7.75°~10.25°.The results show that the four-wheel positioning parameters are optimized in different degrees,it provides data support for the next vehicle optimization(4)The vehicles of before and after optimization were simulated through double lane change test and slalom test,the driver's burden,rollover risk,slip risk and speed index were compared through before and after optimization.After optimization,the maximum of steering wheel angle is reduced from 65.2°to 47.6°,the maximum of steering wheel angle velocity is reduced from 32.6°to 28.3°,the maximum of roll angle is reduced from 3.5°to 3.3°,the maximum of left front wheel lateral force is reduced from 2300N to 1100N,the maximum of longitudinal velocity is improved from 36.2m/s to 36.4m/s.Optimized steering wheel angle,roll angle,left front wheel lateral force amplitude become smaller,optimized vehicle speed is improved.The results show that the driver's load index,rollover risk index,skid risk index and speed index of the optimized vehicle are better than those of before optimization.