Perching and vertical climbing: Design of a multimodal robot

Abstract

We present a robot capable of both (1) dynamically perching onto smooth, flat surfaces from a ballistic trajectory and (2) successfully transitioning to a climbing gait. Merging these two modes of movement is achieved via a mechanism utilizing an opposed grip with directional adhesives. Critical design considerations include (a) climbing mechanism weight constraints, (b) suitable body geometry for climbing and (c) effects of impact dynamics. The robot uses a symmetric linkage and cam mechanism to load and detach the feet while climbing. The lengths of key parameters, including the distances between each the feet and the tail, are chosen based on the ratio of required preload force and detachment force for the adhesive mechanism.