Modeling of steady-state performance of skid-steering for high-speed tracked vehicles

Abstract

This paper presents a high-fidelity, general, and modular method for lateral dynamics simulation of high-speed tracked vehicle. Based on classic terramechanics, a novel nonlinear track terrain model is derived. The track terrain model meets the needs of longitudinal and steering motions, comprehensive track slips, and modular modeling for tracked vehicles with various configurations. The proposed lateral dynamics model is in reasonably agreement with the available experimental data. Using the lateral dynamics model, the main factors (normal pressure distribution, position of gravity center, and ratio of track-ground contact length and tread L/B) effecting the steady state characteristics of skid steering are discussed. The normal pressure distribution is idealized as trapezoid and dual trapezoid distribution to reflect same common driving situation. The under-steer parameter is introduced in this paper to quantitatively evaluate the steady-state characteristics of skid steering for tracked vehicle. The results show that the ratio of theoretical speed difference and average speed of both side tracks Δu/u as the steering input is more suitable for the high-speed tracked vehicle. The vehicle with dual trapezoid normal pressure distribution slightly tending to localize in the middle of track or with slightly rearward position of gravity center has better handling stability characteristics.