A new simulation technique has been developed which shows considerable utility in predicting the tractive performance of four-wheel-drive vehicles. This technique overcomes the usual difficulty encountered in solving a set of nonlinear equations to determine vehicle forces. A unique feature of the model is the prediction of individual wheel forces and slips, thus aiding design of the distribution of tractive power. The simulated results are compared with tractive forces measured on a JD540 Skidder Tractor having four-wheel drive and frame steer.
