The Research Of Rollover Stability And Tracking Ability Control Strategy On The Bus

In recent years, the national economy has been growing vigorously and the transportation showing a good development momentum. Under this situation, more and more buses are putting into use constantly to meet the increasing transport demands. While at the same time, traffic accidents occur frequently, resulting in tremendous casualties and property losses. Because of the higher barycenter, larger passenger capacity and longer travel distance of the bus, the proportion of casualties caused by the bus crash is the highest. Based on this, the bus driving safety has become a common concern of different groups. So studying the rollover stability and the tracking ability of the bus has great realistic meaning to improve the driving safety.Taking into account the complexity of the dynamic behavior of the bus in reality and the focus of the research, this paper established an 8 DOF dynamic model, with the simple and useful “Dugoff” tire model, to study the bus rollover stability and tracking ability. This model is able to meet the simulation requirements of the bus extreme conditions and accurately simulate the status of bus rollover and/or lane departure. And then we verified the model using the MATLAB/SIMULINK software. This paper proposed rollover stability and tracking ability coordinated control strategy, using the yaw rate, sideslip angle and path deviation amount as a system control variables. By the analysis of the triggering conditions of the bus anti- rollover and tracking ability, as well as the bus running parameters, this paper proposed a critical value weight control algorithm, designed more than one fuzzy controller and used the combination control of active steering and differential brake to verify the simulation model in the MATLAB/Simulink. The results show that compared to the single rollover control, coordinated control can prevent the bus rollover, ensure it traveling in the proposed route in the meantime and better improve the bus driving safety.In the MATLAB/Simulink software, the strategy proposed above has been analyzed and verified under J-turn condition and Slalom condition on the road with high/low adhesion coefficient. The simulation results show that this control strategy, with better robustness and self-adaptability, can improve the bus rollover stability and tracking ability effectively.