Abstract
The objective of the research is to investigate the turning characteristics of a two-axle four-wheel vehicle at steady state circular turning on sandy soft terrain. The axle load, lateral force, thrust and effective tractive effort acting on the wheeled vehicle turning on soft and hard terrain were compared. It was observed that the directions of lateral force acting to the front wheel of vehicle running on soft and hard terrain are opposite. Moreover, the lateral force acting to front wheel for the case of vehicle running on soft terrain is larger than that for the case of hard terrain. However, it is found that there is only a little difference between lateral forces acting to rear wheel of vehicle running on soft and hard terrain. It was observed that the axle load of rear wheel was larger than that of front wheel running on soft terrain and the axial force-steering angle relationships of the soft and hard terrain were almost similar. In the case of vehicle under traction on steady state circular turning, it was found that lateral force in direction of turning increased with the increase of effective tractive effort.