Research On Anti-rollover Integrated And Path Tracking Coordinated Control Of Tractor-semitrailer Tank Vehicle

As the main transportation means of liquid chemicals,liquid-filled tractor-semitrailer is more prone to rollover accidents due to its large weight,high center of mass,and liquid sloshing coupled with vehicle in the conditions such as sharp turns,causing serious casualties,economic losses and environmental pollution.An effective active anti-rollover control system can reduce the risk of accidents.At present,the active anti-rollover control strategy mainly takes ordinary four-wheel passenger vehicles or ordinary heavy commercial vehicles as the research object.There are few specific studies on liquid-filled tractor-semitrailer with the characteristics of vehicle-liquid coupling.For the anti-rollover control of semi-trailer liquid tank vehicles,the control strategy based on single actuator is mostly adopted.The control strategy of anti-rollover integration and path tracking coordination is studied.The main work content of this paper is as follows:(1)The dynamics model of liquid-filled tractor-semitrailer is established.Firstly,by equating the effect of liquid sloshing on the vehicle as lateral force and roll moment,the equivalent single pendulum model of liquid sloshing on the cylinder tank was established.The fluid domain model in tank was established by fluid analysis software FLUENT,and the liquid sloshing in tank was numerically calculated by using dynamic grid method.The parameters of the equivalent single pendulum model are identified by the calculated results,and the effectiveness of the single pendulum model is verified by simulation comparison.The tractor-semitrailer model was established by Truck Sim,and the dynamic characteristics of the semi-trailer tank truck were qualitatively analyzed by co-simulation with Simulink.The four-degree-of-freedom and six-degree-of-freedom dynamic models of liquid-filled tractor-semitrailer were established based on the liquid sloshing single pendulum model,which establishing the foundation for the design of anti-rollover control strategy.(2)The integrated control strategy of anti-rollover for liquid-filled tractor-semitrailer is proposed.Firstly,a yaw stability control strategy based on differential braking and a roll stability control strategy based on active anti-roll bar were designed based on traditional anti-rollover control methods.On the basis of the yaw stability control strategy,considering the dynamic characteristics of liquid-filled tractor-semitrailer,the yaw stability and sloshing suppression control strategy based on differential braking was designed.The influence of three control strategies on the handling stability,anti-rollover ability and longitudinal velocity of liquid-filled tractor-semitrailer was analyzed by comparing various simulation conditions.Through mathematical derivation,the coupling mechanism of yaw,roll and sway of liquid-filled tractor-semitrailer was analyzed,and based on this,an anti-rollover integrated control strategy was designed considering the overall performance of the vehicle under different driving conditions.Finally,Truck Sim/Simulink co-simulation verifies that the integrated control strategy can better improve the anti-rollover ability and handling stability of the liquid-filled tractor-semitrailer,while maintaining a higher longitudinal speed than the independent control strategy.(3)The coordinated control strategy of anti-rollover and path tracking for semi-hanging tank truck is proposed.Firstly,an MPC path tracking control strategy was designed to track the position of the tractor’s centroid.The reason of the conflict between path tracking and anti-rollover control is analyzed by simulation.The ideal yaw velocity required for path tracking was calculated by hyperbolic sine function transformation method,and weighted with the expected yaw velocity in the yaw stability control strategy,the path tracking and anti-roll-over coordinated control of liquid-filled tractor-semitrailer was realized.Finally,Truck Sim/Simulink co-simulation verified that the coordination strategy has good path tracking and anti-rollover effect,while avoiding conflicts.Figure [39] Table [7] Reference [86]...