Analysis And Optimization Ride Comfort Of A Coupe Based On Response Surface Model

With the rapid development of the automobile industry, the automobile is getting more and more closely with people’s daily study and the industry and agriculture. In order to enable the people to have a security, highly effective, the comfortable transportation environment, the research about the performance of the vehicle is getting more and more important. Front wheel alignment parameters affect the whole performance of the vehicle, ride comfort is also an important performance which the people pursue, so that people are trying to improve to meet consumer request and enhance market competitiveness.First of all, the response surface method and the theory of multi-body dynamics which is used to establish dynamics model are introduced briefly. The model of vehicle which is used to simulate and analyze is assembled by seven systems including front suspension, rear suspension, driveline, brake assembly, body, steering and tire. Simultaneously the accuracy of the model has confirmed.Secondly, the wheel excitation simulation is carried on and the result that is the front wheel alignment parameters need to be optimized is come out according the relative literature. Based on response surface method and the method of experimental design, the fore front wheel alignment parameters are chose as variables. And then the approximate model about the changed value of front wheel alignment parameters is fitted, and then the optimal combination of front wheel alignment parameters is determined and verified by using kind of mathematical method.Then, triangular and long ramp pulse input and random road surface input experiment simulation which are recommended in the national standard are carried on. Refer to the national standard the evaluation of ride comfort is introduced. As a result, the ride comfort needs to be optimized.Finally, according to the analysis of the factors including radial stiffness and damping of tire, longitudinal locality about engine, connecting stiffness and damping, stiffness and damping of seat, front and rear suspensions which affect vehicle ride comfort the variables are determined and the total root mean squared of acceleration as target value. It constructs orthogonal and rotatable experiment according to central composite theory. Additionally, the object function is estimated by using response surface method. Last but not least, give the optimization result of design factors which make the ride comfort of the vehicle improved.