Study On Simulation System Of Three-Axle Vehicle Based On Dynamic Model

Heavy truck plays a vital role in national life and facilities construction, the dynamic performance development is an important part of the development of heavy-duty vehicles, in which domain each automobile enterprise input a lot of manpower and material resources for research and improvements. Simulation technology provides a powerful tool for the simulation of vehicle dynamics performance. However, the existing dynamics simulation softwares of commercial vehicle are less, which cannot meet the development requirements of modern heavy-duty vehicles. Therefore, the establishment of three-axle vehicle dynamic model and the development of dynamics simulation software will be significant.In this paper, the dynamics research status of passenger cars and commercial vehicles is described, the development status of suspension performance and K&C measurement technology is discussed. And the difficulty of dynamic modeling on commercial vehicles is pointed out based on the analysis of difference between passenger cars and commercial vehicles. The basic theory of computational dynamics of mult-ibody systems which is used in the establishment of three-axle vehicle dynamic model is derived, and existing dynamics simulation softwares of ADAMS and Truck Sim are introduced. Combined with 3-DOF model of three-axle vehicle, the Fuzzy grey correlation analysis method is used to analyze influencing factors of the steady-resonance characteristics of three-axle vehicle, and the influence degrees of suspension K&C characteristic parameters on handling stability are calculated. Finally, based on detailed analysis of the motion characteristics of three-axle heavy vehicle and comprehensive consideration of the effects of suspension K&C characteristics on vehicle performance, 26-DOF nonlinear dynamic model of three-axle vehicle with dual rear tire is established using D'Alember inertia force theory, which has the properties of object-oriented. Moreover, for this model, improved iteration algorithm is used to solve differential equations, simulation system and man-machine interface of three-axle vehicle is realized through Matlab programming. According to the contrastive analysis with ADAMS and Truck Sim, it turns out that the simulation system exceeds Truck Sim in simulation accuracy and exceeds ADAMS in computational efficiency. The simulation system can not only complete simulation analysis of handling stability based on the basic characteristic parameters of the vehicle, improving work efficiency, but also has a certain reference significance for the development of three-axle vehicle dynamics software. Furthermore, the simulation system is also beneficial for the optimization of vehicle design parameters and control of the vehicle performance as well as the development of vehicle control system based on simulation system.