Development of a Small Legged Wall Climbing Robot with Passive Suction Cups

Abstract

In this paper, we develop a small hexapod robot with passive suction cups and realize vertical wall climbing. The passive adhesion mechanisms make the robotic system small and simple, since it requires neither energy nor an additional actuator to stay on the vertical wall. Above all, the passive suction cup is suited to vertical wall climbing because it is strongly attached to a wall with a smooth surface and is simply detached from it by pulling the edge of the cup. These characteristics are intensified according to the decreasing robotic scale. In this study, we developed a small wall climbing robot 12 cm long and 34 g in weight and driven by single degree-of-freedom linkage legs based on the scale effect. Here, the linkage mechanism optimized by a genetic algorithm provided the effective trajectory of the legs and the attachment-detachment cycle. As a result, the robot traveled on the ground at a velocity of 2.7 cm/s and climbed on the vertical wall at a velocity of 2.2 cm/s.