Research on Test Method of Off-road Vehicle Trafficability

Abstract

The off-road vehicle trafficability can guarantee the vehicles to pass the soft soil with certain speed, which is an important technology index for off-road vehicles. By now, the bearing capability of the soil and the vehicle traction are measured respectively to determine whether the vehicles can pass according to the experience. The vehicle trafficability depends on the features of the soil as well as the performance of the vehicles and however, traditional soil measurement method cannot analyze the relationship between the vehicles and the soil thoroughly. Therefore, a new test method should be proposed and studied to obtain the interaction force between the vehicles and the soil accurately in order to evaluate the vehicle trafficability quantificationally. This new method tests the longitudinal force, lateral force, vertical force and wheel torque of each wheel in real time when the vehicles are driving based on studying the force features of the soil and analyzing the influence factors of soft soil on vehicle running. Furthermore, the engine rotation speed and tire pressure are combined to test the interaction force and the torque between off-road vehicles and the soft soil under different working conditions. According to the tested interaction force and the torque between off-road vehicle and soft soil, the vehicle trafficability model is created based on wheel force, including the relationship between engine rotation speed of the vehicles and the wheel driving torque under the situation of the soft soil, the relationship between wheel vertical force and soil compactness and the relationship between wheel longitudinal force and the friction coefficient of the soil. The wheel force test technology is adopted to study the interaction force and the torque between off-road vehicles and the soft soil. As a result, it provides a new approach to evaluate the vehicle trafficability.

F2012-E01-031