Shared Control Strategy for Vehicle Stability on U-Split Road

The steer-by-wire (SBW) system eliminates the mechanical connection between the steering wheel and the carriage wheel. It eliminates various limitations of the traditional steering system, so that the steering ratio of the car can be freely designed and the steering by wire system can achieve good active front wheel steering (AFS) function. In the study of the stability control of vehicles on the μ-split road, there are mainly two methods, one based on vehicle trajectory maintenance and the other based on vehicle dynamic stability control. Both of these control methods have delays, which is not conducive to the trajectory flowing ability of the vehicle when driving on the μ-split road. A shared control strategy is proposed to improve the vehicle’s stability. The purpose of this study is to establish different variable transmission ratio characteristic curves according to the different input signals of the driver and the vehicle, such as angular change speed, steering wheel angle, etc. Based on these conditions, a new model combining driver’s intention with vehicle dynamic model is established, so as to achieve the purpose of judging the stability of vehicle in advance, to reduce the delay time of control and to improve the response speed, which will improve the stability performance of the vehicle.