Mechanism and Optimization of the Shearing Process of Tracked Vehicle Grouser Units in Snow and Soil

The efficient and reliable mobility of special tracked vehicles in polar snow environments is important. The mechanism of grouser units shearing the snow is investigated to improve the driving performance of special tracked vehicles by optimizing the grouser units. The theoretical and finite element models for shearing snow by grouser units are established by comprehensively considering the longitudinal-lateral load states of grouser units. The composition and proportion of longitudinal-lateral shear forces during the snow-shearing process are derived, and the influence laws of grouser structural parameters and snow media properties on the longitudinal-lateral shear forces are analyzed. Based on this, the parameters of grouser units are optimized. A multi-body dynamics model is built to validate the driving performance of the optimized vehicle, and an experimental test system is constructed to comparatively verify the accuracy of theoretical and finite element models. Experimental results show that the optimized grouser unit increases longitudinal shear force by 17.40% and reduces lateral shear force by 3.57%, thereby enhancing the longitudinal traction while reducing the steering resistance. Simulation results indicate an 8.70% reduction in slip ratio during straight-line driving, a 13.79% increase in actual ground traction force, an 18.22% improvement in traction efficiency, and a 2.36% decrease in turning radius. These improvements effectively enhance the comprehensive mobility of vehicle. This study provides theoretical support for terramechanics and dynamics of special tracked vehicles operating in snow environments.