Tractive efficiency of a tracked vehicle

Abstract

This paper deals with the problem of evaluating the tractive efficiency of tracked vehicles. The tractive efficiency concept used is identical to that introduced by Wismer and Luth for wheeled vehicles. In this paper, the tractive efficiency relevant to the track is derived analytically. The resulting expression is a function of the soil strength parameters, vehicle weight, track dimensions, track slip and the transmission coefficient. It is noteworthy that despite the difference in vehicle systems (tracked versus wheeled), and in investigation methods (analytical versus semi-empirical), the expression derived in this paper and that suggested by Wismer and Luth are quite similar. The analysis performed shows that the tractive efficiency function necessarily has a maximum defined by an optimum slip value. It is analytically proven that the maximum tractive efficiency and the maximum tractive force cannot be achieved simultaneously. Nevertheless, the numerical results show that a satisfactory compromise can be achieved. The results of a comparative analysis support the common experience that the tractive efficiency of a track is usually higher than that of a wheel.