On the role of mean maximum pressure as an indicator of cross-country mobility for tracked vehicles

Abstract

The role of mean maximum pressure (MMP) as an indicator of cross-country mobility is reviewed. The values of MMP under a tracked vehicle are predicted using an empirical formula proposed by Rowland and a computer-aided method, known as NTVPM-86. It is shown that values predicted using NTVPM-86 are in closer agreement with measured data than those predicted using Rowland's formula. The variations of MMP with vehicle weight, track width, number and diameter of roadwheels are predicted using both methods over a clayey soil, snow and muskeg. It is found that in most cases, there is a significant difference in the values of MMP predicted using the two methods. It is also shown that Rowland's method takes into account only a limited number of vehicle design parameters and that it can only be employed to predict vehicle mobility in a qualitative manner. On the other hand, NTVPM-86 takes into account all major vehicle design features and terrain characteristics and can be used to predict quantitatively vehicle tractive performance over soft terrain. It is hoped that this paper will stimulate vehicle engineers in the use of advanced computer-aided methods in their practice and that it will encourage further research in this vital area.