Expansion of the terrain input base for nepean tracked vehicle performance model, NTVPM, to accept swiss Rammsonde data from deep snow

Abstract

A study of the correlation between the measured and predicted vehicle performance over undistributed and preconditioned snow using the Nepean Tracked Vehicle Performance Model, NTVPM, has been carried out. It is shown that on undisturbed snow in Fernie, British Columbia, the performance of a BV 206 predicted by NTVPM correlates very well with measured performance obtained in the field. On preconditioned snow, there is also a reasonable correlation between the measured vehicle performance and predicted one using NTVPM. It is found that predictions of vehicle performance made by NTVPM using pressure-sinkage data obtained with the Swiss Rammsonde and with the bevameter are comparable. This indicates that the pressure-sinkage data obtained using the Rammsonde can be used as input to the NTVPM for predicting tracked vehicle performance over snow. It is shown that in comparison with an earlier version, NTVPM-85, the latest version of the Nepean Tracked Vehicle Performance Model, NTVPM-86, which takes into account fully the characteristics of roadwheel suspension systems, provides improved predictions of vehicle performance over snow where track sinkage is significant. It is suggested that the computer simulation model NTVPM, using pressure-sinkage data obtained by the Rammsonde as input, could form a useful interface with cone based models, such as the NATO Reference Mobility Model, to provide them with an additional capability of predicting tracked vehicle performance over snow.