Variable Speed Limit Method Research In Mountainous Area Based On Vehicle Dynamics System

With the development of mountain road mileage and number of motor vehicles, road accidents are increasing year by year, more serious than accidents in the plain areas. All road traffic accident in the mountains, vehicle speeding is an important incentive, and the curve account for a large proportion in all mountainous traffic accidents caused by speeding. Therefore, the vehicle safety when driving on circular curved road sections in mountainous area is a pressing problem, it is necessary to reasonably control the speed and ensure the traffic safety; the speed limit on circular curved road sections is one of the important measures to improve security. In the past, researchers are mainly conducted research from two aspects of vehicle and road respectively. Through research found that the interaction of vehicle and road played an important role in traffic safety, so the study of vehicle-road coupling is an important issue to solve the vehicle driving safety.A variable speed limit strategy for vehicles under different weather conditions is proposed based on the vehicle system dynamics.It’s on the basis of analysis to speed limit methods on circular curve road sections in mountainous area. The vehicle motion characteristics when driving on circular curve road sections using the principle of the vehicle handling stability was studied. Integrated with the DUGOFF nonlinear tire model, the vehicle dynamic model for cars and trucks was developed respectively. Then the influence of superelevation, road friction coefficient and circular curve radius on vehicle steering stability under various speeds was analyzed, and put forward the concept and calculation method of vehicle dynamic secure boundary. It is indicated that compared with the other two speed limit method, the proposed method can accurately reflect the impact of complex road alignment and road condition on dynamic instability boundary, thus it can provide a reliable theoretical basis for speed limit on circular curve road sections in mountainous area. Mountainous area traffic safety can be improved and effective prevention of road traffic accidents.Variable speed limit method based on vehicle system dynamics is certainly innovative, not only can offer a theoretical reference for the mountain road design, but also provide theoretical support for the development of safety warning for mountainous road and has a certain practical significance for the protection of the mountain road traffic safety.