Switched control for reducing impact of vertical forces on road and heavy vehicle rollover avoidance
Résumé
The aim of the presented work consists in developing a hybrid active control system in order to reduce the impact of vertical forces on the roads and therefore to avoid the rollover of heavy vehicle. The controller is based on super twisting algorithm. Two states are then fixed which correspond to controller ON and controller OFF. They are based on the lower limit and the upper limit of lateral acceleration. These last have been computed from the fixed lower limit and upper limit of Load Transfer Ratio. The system switches between these two states in order to control the vehicle. An estimator based on the sliding mode observer is also developed in order to estimate the vehicle dynamics, such as yaw rate, roll angle, and lateral acceleration. The lateral positions and speeds are then controlled in order to limit the lateral acceleration of the vehicle, reduce the effect of impact forces and prevent the rollover risk of the vehicle. In order to show the quality of this assistance system, simulation and experimental results are given in this paper. Ramp and chicane tests are then presented.