AnyClimb-II: Dry-adhesive linkage-type climbing robot for uneven vertical surfaces

Abstract Vertical wall surfaces with obstacles present a serious challenge for wall-climbing robots. Owing to their limitations in overcoming obstacles, these types of robots have not been commercialized yet. Several ideas on novel designs and precise control have been suggested; however, further research is required to achieve enhanced robot capabilities in overcoming obstacles. Specifically, the use of dry adhesive methods by wall-climbing robots to climb over obstacles present tremendous challenges. This study introduces the design of a new linkage-type, wall-climbing robot, based on dry adhesion, for uneven vertical surfaces. Based on a four-bar mechanism, repeated walking is achieved via a single actuator. The robot's most important feature is the linkage design used for climbing over obstacles, which has been adopted from rover running patterns. The symmetric linkage design renders the robot adaptable to uneven surfaces with a compliant motion. Additionally, flat dry adhesives were used for the attachment mechanism. The design parameters were determined based on kinematic and static analyses, and certain important issues in linkage-type wall-climbing robot designs were addressed. The robot's performance was verified using experiments, whereby it was able to climb up and go down stairs with maximum stair heights of 15 mm (equal to 0.6% of the robot's height) during open-loop vertical walking. We expect that the linkage design can extend the accessible area of the wall-climbing robot. This study introduces the design of a new linkage-type, wall-climbing robot, based on dry adhesion, for uneven vertical surfaces. Based on a four-bar mechanism, repeated walking is achieved via a single actuator. The robot's most important feature is the linkage design used for climbing over obstacles, which has been adopted from rover running patterns. The symmetric linkage design renders the robot adaptable to uneven surfaces with a compliant motion. Additionally, flat dry adhesives were used for the attachment mechanism. The design parameters were determined based on kinematic and static analyses, and certain important issues in linkage-type wall-climbing robot designs were addressed. The robot's performance was verified using experiments, whereby it was able to climb up and go down stairs with maximum stair heights of 15 mm (equal to 0.6% of the robot's height) during open-loop vertical walking. We expect that the linkage design can extend the accessible area of the wall-climbing robot.