Bipedal robotic walking on granular material: An inertial and kinematic control approach

Abstract

Bipedal robotic locomotion in granular media presents a unique set of challenges at the intersection of granular physics and robotic locomotion. In this project, we performed a series of systematic design implementations, trials and experiments to enable a 7 degree-of-freedom planar biped walker to robustly traverse granular inclines. We hypothesize that, through the optimization of open loop gait, variation of inertial properties, and development of contact area control, a robust locomotion system for biped robotic locomotion on granular media can be identified. While the balancing and locomotion of biped systems has been widely studied for decades, these systems are typically in the context of body-based balancing on hard ground. Such schemes largely encompass control based on body and joint torques as a way to stabilize the biped system. However, when faced with complex, highly non-linear complex matter, such as granular material, these techniques alone are insufficient. This presentation discusses the development of a gait system and control scheme that encompasses static inertial changes through torso re-positioning, and dynamic contact area variation, to allow for robust, steady gait over granular media.