硬质路面条件下履带车辆转向模型分析及验证

The interaction between tracked vehicles and the ground is complex. In general, methods based on shear stress-shear displacement theory require the integration of time and position, which is complicated and rarely applied to real-time vehicle control algorithms. Turning analysis of tracked vehicles typically assumes that grounding pressure is uniformly or concentratedly distributed. However, the calculations and test results show that the track-ground pressure forms multiple peaks on hard ground. In view of the above problems, based on previous studies, this paper proposes a simplified model of track-ground pressure, which has good consistency with the actual track-ground pressure on hard road surfaces. The model is then applied to the dynamic analysis of tracked vehicle turning. The vertical pressure-shear displacement relationship proposed by J. Y. Wong is employed to calculate the shear displacement when the track-grounding pressure keeps changing. A steering discretized model for tracked vehicles is proposed, and the test results show that the model has high accuracy yet still high complexity. To further simplify the model, the concepts of wheeled vehicle tire slip angle and slip rate are used. Then, a simplified tracked vehicle dynamics model is derived by using the shear stress-shear displacement theory. It avoids complex integration or summation, and can be applied to model-based motion control methods. Besides, it is almost as accurate as the complex steering analysis model.