Study On The Correlation Between Subjective And Objective Evaluations For Handling And Stability Of Passenger Vehicles

During the development and design of passenger car’s handling stability, the evaluation work is operated by subjective evaluation, objective evaluation and computer simulation together. To get the perfect corporation of the methods above, it is necessary to acquire the relationship between the subjective and objective evaluation. Therefore, in this paper, the relationship between the subjective and objective evaluation of passenger car’s handling stability is studied.The essence of establishing the relationship between the subjective and objective evaluation is to obtain the mathematic relation. Thus, based on the evaluation system home and abroad, the subjective evaluation system is put forward, which consists of 20 evaluating indicators of 4 evaluating aspects with steering ability, curving ability, steering force characteristics and deformation-resisting steering ability included. With the method of 10-point evaluating scale, 4 vehicles’ subjective evaluating scores are acquired. And then, the weight of each evaluating indicator and the total score of each vehicle is calculated by Entropy Evaluation Method.The data of objective evaluation is acquired by Steering wheel angle pulse test, Pylon course slalom test and Central steering wheel test with V-BOX3 i. Based on the national standard, 27 objective evaluating indicators are initially selected and 10 indicators are rejected after the Correlation analysis method.Multiple linear regression(MLR) is used to get the relationship between the total score and objective evaluating indicators. With the same method, the relationship between the subjective and objective evaluating indicators is acquired. For the indicator pairs which don’t possess linear relationship, nonlinear regression analysis is used to fit the sample points and the nonlinear relationships between them are obtained. The result shows that 8 subjective evaluating indicators possess binary linear relationship, 10 indicators possess unary linear relationship and 2 indicators possess binary nonlinear relationship with each related objective evaluating indicators. Among those 10 indicators which possess unary linear relationship with related objective evaluating indicators, 7 indicators are related with Resonance Hump Level, which indicated that Resonance Hump Level is the most important objective indicator to influence the subjective evaluation score.