Automobile Suspension System Dynamics Analysis And Simulation

Virtual Product Development is modern advanced mechanic design, analysis method and developing orientation. It is availability and reliable method in exploiting and improving vehicle suspension and whole vehicle. Along with the developing of computer's capability and the popularity of CAD, application of virtual prototype technology and method become more beneficial, and is used to development of the vehicle, which decreases the week of development, increases efficiency and precision, and detracts develop cost. Because Shan' Xi Automobile produce Inc will manufacture heavy automobile that adopts Independent Suspension in the three-axle, the thesis utilize Virtual Product Development to simulate and test the suspension system and the whole vehicle, expecting that academic foundation can be provided to practical exploitation of this vehicle type.This thesis uses ADAMS (Automatic Dynamic Analysis of Mechanical System) to investigate a three-axle vehicle suspension system. The first, 3D multi-body free limit dynamical models of front and rear suspensions that apply Double Wishbone Independent Suspension are built. And through the single wheel parallel vertical travel dynamic simulation and the wheel parallel vertical travel dynamic simulation of front suspension and rear suspension, this thesis analyzes major parameters' mathematic models of suspension, and finds that CasterAngle of in fore front suspension device project can't fulfill device desire, but the rear suspension can fulfill device desire. In this way, the whole vehicle 3D multi-body free limit dynamical model is established, which includes front, middle and rear suspension system, steering system, tire and pedestal etc. There is simulation, trial and analysis to the whole vehicle model in condition of empty load and full load. In the case of linear acceleration and urgent brake, we find anti-dive and anti-lift performance is bad in fore front suspension device project. Then front suspension is optimized from adjusting oriented framework of suspension. At last, we simulate, assay and analyze steering wheel angle step input test and steady static circular test according to the test methods of handling stability inGB/T6323-1994, when the whole model is in condition of full case and empty case. Find that the vehicle model has suitable short steering peculiarity, and that along with the enhancing of speed, the fluctuation of rotary angular velocity and side-acceleration become more and more large and instantaneous response time becomes longer, and that rotary angular velocity and side-acceleration in full case is bigger than in empty case, and instantaneous response time in full case is longer than in empty case.In all, this thesis is combination of production, study with research, analyzing and estimating problems with theory and forth-goers' experience. The simulation, trial and results of Double Wishbone Independent Suspension will provide reliability reference to factory, which is far-reaching significance.