ANALYSIS OF TRACKED VEHICLES TURNING ON LEVEL TERRAINS

Steerabilityy represents one of the principal measures of tracked vehicles mobility. Study of turning problems provides the possibility of steerability prediction. Several papers on the subject were concerned mainly with the kinematic response of vehicle during turning, taking into consideration the track slip. This paper deals with turning from the point of view of the required forces on tracks for a specified turning process and accordingly, the track slip was neglected. That helps in determining the required power to be developed by engine for turning, which is essential for the selection of engine and vehicle configuration in case of a new design, or for evaluation and development of an existing design. A mathematical model for the kinematic and dynamic parameters neglecting the track slip, was developed through a theoretical analysis. The equations of vehicle motion during turning were derived and solved for the required forces on tracks, limited by the adhesion conditions with ground. Since the average speed of modern tracked vehicles has been augmented remarkably, the model was developed for the general case of nonuniform turning where the effect of inertia forces was considered. The influence of speed on turning parameters was investigated numerically for a selected vehicle on a computer program applying the theorectically derived model. The simulation results with discussion and conclusions are presented.