Ride Comfort And Handling Stability Study Of Passenger Bus With Laterally Interconnected Air Suspension

The interconnected air suspension acts as a derivative structure developed from conventional air suspension.It uses the pneumatic pipelines to connect the adjacent air springs in the conventional air suspension,so that the gas in the air springs could be fully exchanged.Then,the adverse impact of the road to the vehicle and passengers can be effectively mitigated.Therefore,on the basis of previous research results,studying the influence of laterally interconnected air suspension on the ride comfort and handling stability from the numerical insight,which could provide reference for the development and design of laterally interconnected air suspension on real vehicle.Firstly,the advantages and disadvantages of laterally interconnected air suspension are analyzed with the working principle.Based on the simulation software MATLAB/Simulink and multi-body dynamics simulation software ADAMS,according to research contents of engineering thermodynamics and fluid mechanics,the Simulink simulation model of laterally interconnected air spring has been built based on the mathematical model.And based on the modeling method of multi-body dynamics,the ADAMS simulation model of the main components of laterally interconnected air suspension bus has also been built.By using the co-simulation interface between ADAMS and Simulink,the ADAMS-Simulink co-simulation model of passenger bus with laterally interconnected air suspension has been establishment.And the accuracy of co-simulation model was verified according to the actual vehicle test.Secondly,according to the co-simulation model,the simulation study of random road input ride comfort under the same initial conditions has been carried out for passenger bus with laterally interconnected air suspension and passenger bus with non-interconnected air suspension,respectively.The acceleration simulation results of the two models was compared,and the ride comfort was evaluated according to the evaluation indexes of the two models,respectively.The results showed that the ride comfort of passenger bus with laterally interconnected air suspension was significantly improved compared to passenger bus with non-interconnected air suspension.Then,a conclusion was drawn that the laterally interconnected air suspension has significant superiority in improving the ride comfort of the vehicle.Thirdly,the simulation study of handling stability under the same initial conditions has been carried out for passenger bus with laterally interconnected air suspension and passenger bus with non-interconnected air suspension,respectively.The simulation results of suspension travel,roll angle,yaw rate and lateral acceleration of the two models were compared and analyzed.And the handling stability of the two models was evaluated according to the results of the co-simulation.The results showed that compared with the non-interconnected air suspension bus,the handling stability of laterally interconnected air suspension bus has been decreased under various working conditions.Then,a conclusion was drawn that the laterally interconnected air suspension has negative effects on the vehicle handling stability,and it is necessary to improve and control the handling stability of vehicle with laterally interconnected air suspension.Finally,aiming at the problem of handling stability reduced of the passenger bus caused by laterally interconnected air suspension,the design parameters such as connection diameter of the interconnected air suspension,location of mass center,and sprung mass of the vehicle were modified.After the modification of parameters on bus with laterally interconnected air suspension,the steering wheel angle step input simulation was carried out.The results showed that the laterally interconnected air suspension bus is very sensitive to the change of the interconnection diameter,and a smaller connection diameter is enough to cause the body roll angle to change greatly.And the roll angle of vehicle body could be effectively reduced by decreasing the height position of mass center,moving the mass center forward and reducing the vehicle's sprung mass.Then,handling stability of the vehicle could be improved effectively.