关键词: 多轴轮式车辆, 上装载荷, 矢量化建模, 动力学建模与仿真

Abstract: At present, the iteration period of vehicle equipment is greatly shortened, the cost is constantly compressed, and the performance requirements are constantly improved, so the traditional development and testing methods based on manual experience and manual parameterization are difficult to meet the needs of the industry. Multi-axle wheeled vehicle dynamics model is the basis for rapid development of new vehicle equipment, optimization of vehicle design parameters and construction of control algorithms. However, the commonly used commercial software, which is a black box model, is difficult to obtain the dynamic equations and model gradient information, making it impossible to use it for vehicle global optimization of the design and control parameters; In addition, available theoretical modeling studies of multi-axle wheeled vehicles tend to concentrate the unsprung mass in the body mass for calculation, resulting in large model errors; And the effects of top-loading dynamics have been given less consideration in existing commercial software and theoretical modelling studies. In order to address the aforementioned issues, a vectorized modeling method was employed to construct a 24-degree-of-freedom dynamics model of an 8x8 wheeled vehicle. This was done by considering the influence of longitudinal and lateral motion of unsprung mass and reaction force of top-loaded load on the dynamics of the whole vehicle. The modeling was based on Lagrangian dynamics, and the software development was carried out using C++ and M language, respectively. A comprehensive comparison was conducted between the commercial software TruckSim and the proposed model under a variety of working conditions, including variable acceleration, step steering, double lane change, 90° swept sine steering. The results demonstrate that the tire force, suspension force and air resistance, as well as the longitudinal, lateral and vertical motions of the self-developed simulation model, exhibit high consistency with those of the commercial software, with an error of less than 5%. This verifies the accuracy of the methodology.

Key words: multi-axle wheeled vehicles, top loads, vectorized modeling, dynamics modeling and simulation