Research Of Rollover Control Algorithm Of Tractor Semi-Trailer

Tractor semi-trailer easily happen rollover accident due to its own characteristics. Because of vehicle happen rollover in a very short time, driver is often too late to take effective measures; And once happening rollover accident, the consequence is very serious, even fatal.Therefore, it is particularly important that rollover warning on vehicle super real time to provide warning signals early enough to driver or vehicle rollover control device to take appropriate preventive measures.In this paper, tractor semi-trailer is as the research object. A six axis trailer semi-trailer dynamics model is set up in the TruckSim, presented on TTR-Based vehicle rollover prediction method and the active suspension control algorithm, then carried out co-simulation based on TruckSim and MATLAB/Simulink software.First of all, according to the vehicle dynamic lateral load transfer ratio LTRd determine the vehicle roll angle threshold, realized the prediction method based on roll rate. Secondly, study on active suspension control algorithm. Construction of the active suspension with three control mode of sliding mode structure control, PID control and fuzzy control, and design the controller based on the three kinds of control algorithm.And established combined control system based on TTR rollover warning for tractor semi-trailer anti-rollover control. In addition, this dissertation presented an optimization method based on MATLAB Optimization Toolbox to optimize the parameters of designed active suspension controller.Finally, co-simulation were carried out by TruckSim and MATLAB/Simulink software, respectively in fishhook condition, double lane change condition and steering wheel angle step input condition to test anti-rollover stability control of tractor semi-trailer.The simulation results show:the combined control system based on TTR warning can be effectively carried out anti-rollover control of tractor semi-trailer. PID control, sliding mode variable structure control and fuzzy control can greatly improve the vehicle roll stability, and reduced effectively rollover, jackknifing and yaw instability accidents of tractor semi-trailer.