A leg-wheel wall-climbing robot utilizing bio-inspired spine feet

This paper presents a leg-wheel wall-climbing robot utilizing bio-inspired spine feet, which is called LWbot (a leg-wheel robot). It is a 14 mm long and 57 g weight robot. It is capable of climbing both vertical brick surfaces and penetrable surfaces, such as curtains and polystyrene foam boards. It can climb not only upward, but also downward. The climbing speed on vertical curtain is up to 9.5 cm/s. LWbot consists of a passive wheel and two groups of legs which are equipped with modified Chebyshev four-bar linkages and compliant spine feet. A single motor drives the four-bar linkages to move continuously to achieve the movement of insects´ climbing, and the “D” shaped trajectory of foot tip makes the miniature spines easy to penetrate in (or cling on) and pull off the surfaces. Moreover, the compliant foot mechanism inspired by the structure and mechanism of the tarsal chain in the cockroach makes the attachment more reliable.