Optimal study of the Initial Track Tension for the track vehicle under soft ground based on multiple operating conditions

Abstract

The determination of Initial Track Tension (ITT) is an important issue for the moving performance of tracked vehicle under soft ground. At the present time, however, the selection of ITT only according to a moving performance or an operating condition under hard ground. Focus on this, a novel approach for determination of ITT without changing the basic vehicle parameters is proposed in this paper, which can improve the moving performance under soft ground comprehensively. Analytical models for predicting ground pressure under tracked vehicle on soft ground including ITT were used based on the track-soil coupling relationship, movement characteristics and turning characteristics of an articulated track vehicle, which applied to the straight driving condition, steering-driving condition and climbing condition. The intrinsic mechanisms between the ITT and the Mean Maximum Pressure (MMP) under roadwheels were revealed. The stresses produced by the action of track and sprocket, roadwheels, idle wheel, soil respectively were studied in consideration of the vehicle-soil mechanics theory and strength theory. The stress state and changes for an element of the track were investigated. What’s more, the relationship between the ITT and fatigue life of the track was explained in detail based on the Miner’s rule. On this basis, an optimal study for the ITT was performed taking advantage of NSGAII, which used the MMP under roadwheels and fatigue life of track as optimization objectives. And then, the determination principles of the ITT were presented, and it was identified by an articulated track vehicle. The results are significant to the prediction and control of the moving performance of track vehicle under soft ground.