Development of motion model and position correction method using terrain information for tracked vehicles with sub-tracks

Gyro-based odometry is an easy-to-use localization method for tracked vehicles because it uses only internal sensors. However, on account of track-terrain slippage and transformation caused by changes in sub-track angles, gyro-based odometry for tracked vehicles with sub-tracks experiences difficulties in estimating the exact location of the vehicles. In order to solve this problem, we propose an estimation method with 6 degrees of freedom (DOF) for determining the position and pose of the tracked vehicles using terrain information. (In this study, position refers to the robot's position and pose.) In the proposed method, position are estimated using a particle filter. The subsequent position of each particle are predicted using a motion model that separately considers each contact point of the vehicle with the ground. In addition, each particle is analyzed using terrain and gravity information. Experimental results demonstrate the effectiveness of this method.