Steerable dry-adhesive linkage-type wall-climbing robot

Abstract

Steering a wall-climbing robot on a vertical surface is challenging because the angle of gravity and motion trajectory are continuously changing. There is an additional degree of freedom when steering a wall-climbing robot on a vertical surface compared with only climbing forward. This study presents a steerable linkage-type wall-climbing robot with walking locomotion for flat vertical surfaces. A parallel four-bar linkage mechanism connecting the inner body frame to the outer body frame was designed to implement walking locomotion by linkage rotation. Additionally, to achieve high and continuous steering speed a simple steering mechanism was designed with a single servo motor and two bevel gears. This wall-climbing robot using a dry adhesive system with flat elastomer, and the dry adhesion method is applicable to various material surfaces. Furthermore, failure analysis was conducted to determine the stable steering angle when the robot was climbing on a vertical surface. Finally, a performance assessment confirmed the steering stability of the wall-climbing robot on a vertical surface. The forward-climbing speed of the robot is 13.3m/s, and it can stably complete the steering motion at angles less than 55° in 5s.