Gait Design Using Self–Manipulation

Design insight into steady–state locomotion requires careful analysis of the dynamics within and transitions among the combinatorially many possible contact conditions that a legged robot will experience. To that end the self–manipulation formalism, originally intended to aid in the analysis of dynamical transitions, leans on the well established manipulation literature to systematically populate these continuous and discrete dynamics and apply a consistent structure that has proven to be useful in the analysis of grasping tasks. These ideas are instantiated on RHex with a pronking gait in which all legs are used together. Here a new behavior is presented that is both significantly faster than prior pronking gaits and also inherently stable allowing for open-loop operation. This new, stably robust pronk will enable dynamic transitions such leaping from running in any stride without requiring a decision two strides ahead of the leap. Keywords–Legged locomotion; robotics; motion analysis