Abigaille-III: A Versatile, Bioinspired Hexapod for Scaling Smooth Vertical Surfaces

This paper presents a novel, legged robot, Abigaille-III, which is a hexapod actuated by 24 miniature gear motors. This robot uses dual-layer dry adhesives to climb smooth, vertical surfaces. Because dry adhesives are passive and stick to various surfaces, they have advantages over mechanisms such as suction, claws and magnets. The mechanical design and posture of Abigaille-III were optimized to reduce pitchback forces during vertical climbing. The robot's electronics were designed around a Field Programmable Gate Array, producing a versatile computing architecture. The robot was reconfigured for vertical climbing with both 5 and 6 legs, and with 3 or 4 motors per leg, without changes to the electronic hardware. Abigaille-III demonstrated dexterity through vertical climbing on uneven surfaces, and by transferring between horizontal and vertical surfaces. In endurance tests, Abigaille-III completed nearly 4 hours of continuous climbing and over 7 hours of loitering, showing that dry adhesive climbing systems can be used for extended missions.