The Dynamics Simulation Research On Bus Equit With Air Spring Suspension Based On ADAMS

With stiffness density variation characteristic of the air spring, which makes the vehicleequipment with air suspension handling stability, smooth and comfort are improved greatly.Therefore, air spring suspension becomes an inevitable trend. Recently all upper andintermediate full-sized buses are required to equipment with air spring，also some limousineand special vehicles are supplied with the air spring. It’s significance to match air springsuspension with vehicle.Taking an air suspension bus as the research object then put forward a kind of air springsuspension and vehicle properties matching method. In the multibody system dynamicssoftware ADAMS/Car, established the front suspension, rear suspension and RCB steering,determine the characteristic parameters of tire, based on this the whole vehicle model isestablished including brake, powertrain and body system. Firstly, the paper make the theorycalculation and the simulation of air spring important performance parameters, includingvertical stiffness, suspension roll rate and natural frequency, verify the correctness and therationality of the model; At the same time, the air suspension performance parameters with thechange of standard height and spring bearing force, which make the selection reference of theair spring. Second, the combination of MDI_SUSPENSION_TESTRIG to front suspension,the Wheel Travel and Static Load, Turning test, test K&C characteristics of the suspensionsystem, check wether it meet the design requirements; And from the forces of lateral force andlongitudinal force, analysis and evaluation for suspension model of the turning characteristic,longitudinal force ecceed to lateral force for understeer characteristics. Finally, compareSteady Turning road test with simulation experiment to verify the correctness of the virtualprototype of the bus. Then analysis the vehicle handing stability, including steering wheelAngle step inputs, step steer, impulse steer and fish hook test, the results indicates that the airspring bus handing stability get much improved.