Integrating Dry Adhesives and Compliant Suspension for Track-Type Climbing Robots

Climbing robots using dry adhesives in the literature typically exhibit minimal payload and are considered useful for tasks involving light-weight sensors, such as surveillance or exploration. Existing designs demonstrate small payloads primarily because they either employ minimal adhesion area or fail to distribute the adhesion forces over the adhering region of these robots. Further, existing design methods do not demonstrate scalability of payload-to-vehicle size and, in fact, indicate that such robots are not scalable. However, dry adhesives routinely demonstrate adhering pressures in the range of 20–50 kPa which suggests that a 30 × 30 cm robot could have a payload on the order of 20–50 kg. This paper presents a step-by-step approach for designing track-type dry adhesive climbing robots to achieve high payloads. The aforementioned design steps are then experimentally validated, showing that high payloads should theoretically be possible when using dry adhesives to climb. By integrating a general adhesion model with a suspension system, this design procedure can be used to design climbing robots that distribute the payload over a large adhesive area. The models behind the design procedure (developed previously [1] but summarized here) simultaneously consider the behavior of both the adhesive material at the track-surface interface and the distribution of the adhesive forces over the full contact surface. When each of these criteria are satisfied, track-type climbing robots can be designed to carry high payloads, thus enabling applications previously thought to be impossible.