Traversal Cost Modeling Based on Motion Characterization for Multi-legged Walking Robots

In this paper, we concern a traversal cost estimation considering motion control of a hexapod walking robot. The proposed idea is motivated by the observation that the traversal cost depends not only on the traversed terrain but also on the robot motion. Based on the experimental deployments, the forward motion is preferable over some terrains; however, uphill and downhill locomotion over the particular terrain might differ significantly. Therefore, we propose to enhance the traversal cost model by a motion characterization. The model is learned using feature descriptor composed of terrain shape and appearance that is combined with the expected motion performance determined from the slope change and possible rotation of the robot. The traversal model enables to reason about the robot stability regarding placement of the robot legs and performed motion action. The proposed idea of motion characterization is demonstrated and experimentally verified on a simplified motion control using grid-based planning with the robot control decomposed into straight and turn movements.