A Multibody Model Calibration Method for Vehicle Misuse Testing

This paper proposes a multibody model calibration method for vehicle misuse testing. During misuse tests conducted at high driving speeds, the vehicle’s responses can become highly nonlinear due to certain key model parameters. Direct calibration using a complex multibody model is time-consuming and unstable, as it may fail or diverge due to improper settings of the model parameters. Therefore, a modified quarter-vehicle model is proposed for the analytical calibration of these nonlinear parameters by introducing an additional constraint on the sprung mass to recover the restoring force. The new model features only two degrees of freedom and incorporates key nonlinear parameters, including the suspension’s stiffness and the wheel’s center mass. It is suitable for misuse tests involving tire detachment at high driving speeds. The detailed analytical calibration procedure for the nonlinear parameters is deduced and subsequently validated through numerical simulation using these parameters. When the parameters are sufficiently close to the actual ones or linearly related to the responses, an optimization method such as the least squares method can be applied, along with simulations using complex models in commercial software.