ROLL CHARACTERISTICS OF ALL-TERRAIN VEHICLE BASED ON CROSSING DOUBLE AIR CHAMBER PNEUMATICALLY INTERCONNECTED SUSPENSION

For the all-terrain vehicle with extremely high incidence of rollover accidents, a cross-type double air chamber pneumatically interconnection suspension using a capsule air spring is designed. A crossing double air chamber gas coupling AMEsim model and an all-terrain vehicle dynamics ADAMS/Car model are established. By taking the change of elastic force of air spring in the former model as the input variable of the vehicle dynamics model, and the compressional displacement of air spring in the latter model as the input variable of the gas coupling model, a complete mechanical-pneumatically coupling multi-degree of freedom dynamic joint simulation model is established. The roll characteristics of an all-terrain vehicle equipped with a crossing double air chamber pneumatically interconnected suspension(PIS), a crossing double air chamber pneumatically unconnected suspension(UN-PIS), and a common helical spring suspension(HS) are compared with the simulation experimental conditions. The results show that if the PIS system closes the interconnection pipeline, the UN-PIS system will be formed, which causes the suspension stiffness to rise sharply in an instant and the ride performance to deteriorate in an instant. On the premise of guarantee consistent vertical stiffness, PIS can provide greater lateral stiffness than HS. The factors affecting the dynamic roll characteristics in the gas pipeline system are researched, including the pipe length, pipe diameter and the volume of additional air chamber. The research shows that the shorter the pipe length is, the more beneficial it is to improve the roll characteristics of all-terrain vehicles. And there is a critical pipe diameter, when the pipe diameter is less than or greater than this value, the roll characteristics will be slightly improved. And the smaller the volume of the additional air chamber, the greater the lateral stiffness. Which provides a theoretical basis for the design of PIS system.