耦合上装载荷的多轴车辆动力学建模与仿真

Multi-axle wheeled vehicle dynamics model is the basis for the rapid development of new vehicle equipment, the optimization of vehicle design parameters and the construction of control algorithms. The commonly used commercial software is difficult to obtain the dynamic equations and model gradient information so that it cannot be used for the dynamic optimization of vehicle global design and control parameters. 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 is employed to construct a 24-degrees-of-freedom dynamics model of an 8×8 wheeled vehicle based on Lagrangian dynamics,which considers the influences of the longitudinal and lateral motions of unsprung mass and the reaction force of top load on the vehicle dynamics. The modeling is based on Lagrangian dynamics,and the software is developed using C++ and M languages,respectively. The proposed model is comprehensively compared with the commercial software TruckSim under a variety of working conditions, including variable acceleration, step steering, double lane change, 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 proposed 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.