A Terrain-Vehicle Interaction Model for Analysis of Steering Performance of Track-Laying Vehicles.

摘要

This report documents the development of a mathematical model for predicting the steering performance of track-laying vehicles in environments ranging from soft soils to hard surfaces such as rigid pavements. The tractive forces between the terrain and the vehicle track are simulated by a rheological model that accounts for nonlinear shear-stress/shear-deformation relation, the effect of deformation rate on shearing resistance, and the effect of pressure on shear resistance and plastic yielding. The rheological model is coupled with the kinematics and the characteristics of the vehicle to develop the equations governing the transient motion of a vehicle on a level flat surface and the steady-state turning motion on a sloping terrain. A computer program, named AGIL, numerically integrates and solves these equations of motion in terms of the kinematics of the problem. The computer program is used to investigate parametrically the steering performance of a specific vehicle on different types of terrain and to examine the effect of vehicle charcteristics on steering performance. Appendix A of this report presents a procedure for determining the coefficient of rolling resistance. Appendix B gives recommended stability criteria for uniform turning motion. The field direct shear device is described in Appendix C. (Author)