Research On Rollover Prevention Of Vehicle Based On Differential Braking Technology

With the rapid development of automobile industry and the enhancement of highway construction, the vehicle speed has been greatly improved. Along with these growth is more accidents, which caused more serious loss of property and life safety. The driving safety of the automobiles has caused widespread concern of the society, and the handling stability of the vehicle becomes the key point of the research. As one kind of traffic accident, vehicle rollover draw people’s attention, and more and more experts and scholars have devoted to the research of this field. Our country’s research on rollover prevention is still at the starting stage, so the rollover prevention research has important practical significance and broad market prospect.Establishing a rollover dynamics model of vehicle is the foundation of research on rollover prevention of vehicle. Lateral load transfer ratio is used as an important index to measure the rollover condition of vehicle. This research established the nonlinear tire model based this index, and on the basis of the established model, four freedom whole vehicle model is established which can reflect the moving state of the vehicle and used as a platform for the research of vehicle anti rollover control.Differential braking technology can adjust the movement through changing the steering characteristics and mechanical properties of the vehicle. Through the deep analysis of anti-rollover control principle and the differential braking technology’s effect on mechanical characteristic of the vehicle, this paper established an anti-rollover dynamics model based on the lateral load transfer ratio, and make the numerical simulation analysis. Compared with ordinary braking and no braking condition, the consequence proved that using differential braking technology will have a better result on rollover prevention. What’s more, it analyzed the effect of different sizes of braking force on the motion state and parameter of the vehicle, which provides a basis for rollover prevention.Through the analysis of PID control and fuzzy control performance, this paper combined fuzzy PID control with preview optimal curvature driver model and established the trajectory control driver model. This model can adjust the parameter of PID controller according to the error between the actual and ideal vehicle lateral acceleration, which will ensure that the vehicle can run according to the requirement of road track.Finally, this research put vehicle dynamics model, rollover prevention system and trajectory control driver model together to make simulation experiment. The simulation results showed that this control not only can avoid the risk of vehicle rollover effectively, but also can reduce the driving track offset due to differential braking, which can effectively improve the maneuverability and stability of the vehicle.