Optimization method of vehicle handling stability based on response surface model with D-optimal test design

In order to improve the handling stability of a vehicle, an optimization method of vehicle handling stability based on D-optimal test design was proposed in this paper. The multibody dynamic model was established and verified by experiments. On this basis, a response surface model was established based on D-optimal test design. An improved genetic-particle swarm algorithm was used to optimize the vehicle handling stability. The general evaluation score of vehicle handling stability was taken as the optimization objective. The vehicle structural parameters, tire and spring characteristics were regarded as design variables. The results showed that the multi-body dynamic model was accurate. After optimization, the general evaluation score of vehicle handling stability increased by 8.98 %; the score of the steering returnability and steady static circular test was increased by 20.43 % and 27.31 %, respectively. Then from the sensitivity of the optimization variables to the stability of the vehicle's handling, the rear wheel lateral stiffness has the greatest impact on it, with a sensitivity of 86.9 %; the wheelbase has the smallest impact on it, with a sensitivity of -3.39 %, which can be reduced in future optimization variable to improve design efficiency.