Study on Skid-Steering Drag Force Calculation and Model for Electric Ground Vehicle with Six In-Wheel Motors

The skid-steering vehicle is able to be steered by the speed difference of the inside and outside wheels created by controlling the torque distribution of all drive wheels. The three degree of freedom dynamic equations are established for electric ground vehicle with six in-wheeled motors, based on which the drag force calculation model is presented under steady skid-steering condition. Then the variation of resistance torque with the steer input and vehicle velocity is analyzed including its theoretic constraint limit. The steering resistance moment of the electric ground vehicle is compared with that of the tracked vehicle with the same vehicle parameters. In order to validate the calculation results, the virtual prototype model is created and the dynamic simulation is executed in ADAMS software. The results indicate that the resistance moment of electric ground vehicle is more than that of the tracked vehicle with same configurations and the computational model is correct.