In this paper, flat elastomers are proposed as an attachment material for climbing robots on less than a few micrometer-scale rough surfaces due to their energy-efficient, quiet, and residue-free characteristics. The proper elastomer is chosen by the use of the current adhesion, friction, and peeling elastomer-contact-mechanics models. Then, adhesion and friction properties of the chosen dry flat-elastomer thick films (Vytaflex-10) are characterized on acrylic and smooth and rough glass surfaces for variations in preloads, speeds, contact times, and elastomer thicknesses. A climbing robot with four-bar-based legged-body kinematics is designed and fabricated as simple and lightweight as possible to demonstrate the feasibility of the elastomers as attachment materials on relatively smooth surfaces. The robot utilizes a passive alignment system to make the footpads parallel to the surface on light contact, a peeling mechanism to minimize the detachment vibration, and a passive tail to minimize the pitch-back moment. Experimental results showed that the robot can climb stably on vertical, smooth surfaces in any direction and can walk inverted for a limited amount of time.

In this paper, the design, analysis, and development of a sixteen-legged palm-sized climbing robot using flat bulk tacky elastomer adhesives as an attachment method is presented. A legged robot with four-bar based kinematics is designed and fabricated with elastomeric footpads. The proposed robot has a passive peeling mechanism for energy efficient and vibration free detachment. A rocker-type mechanism in the leg and compliant foam under the footpads are utilized for passive alignment on concave and convex surfaces. Adhesion experimental data is used to estimate the adhesion and preload saturation on the footpads on different angled acrylic surface. It is showed that although the initial preload does not affect the adhesion and preload saturation point, the orientation and the weight of the robot, roughness of the surface, and waiting time between consecutive steps greatly effect the climbing performance. Experimental results revealed that the robot can climb in any direction in 3D space on smooth surfaces, such as acrylic and glass. It can carry a payload of up to 2 N, which is almost twice as its own weight, on a smooth inverted surface. The robot can robustly climb vertically on relatively rough surfaces such as a painted wall or a wooden door. Potential applications of this robot include inspection, exploration, maintenance, cleaning, repair, and search and rescue.

Tankbot is a miniature, energy efficient, lightweight (60 g), and robust climbing robot. It uses the continuous detachment force (peeling) of the flat, bulk tacky elastomer tread to climb. An optimum peeling angle with a preliminary analysis of the pretension effect, and the tread force distributions are presented. A passive tail transfers the peeling force from the rear wheel to the front and ensures intimate continuous contact with the surface. Tankbot works in any orientation on smooth surfaces, such as glass and acrylic, of all slope angles (0 – 360 degrees). However, the robot can only work vertically on relatively rough surfaces in any direction, such as wood, metal, painted wall, and painted brick. Tankbot can carry a payload of up to 40 g and 100 g on inverted and vertical surfaces, respectively. In addition, the robot can go over obstacles up to 15 mm tall on smooth vertical surfaces. Internal transitioning from horizontal to vertical and vertical to horizontal and external transitioning from vertical to the horizontal are also achieved. The potential applications of this robot include inspection, exploration, maintenance, cleaning, repair, and search and rescue.

In this paper, the design, analysis, and fabrication of a gecko-inspired climbing robot are discussed. The robot has kinematics similar to a gecko's climbing gait. It uses peeling and steering mechanisms and an active tail for robust and agile climbing as a novelty. The advantage of this legged robot is that it can explore irregular terrains more robustly. Novel peeling mechanism of the elastomer adhesive pads, as well as steering and stable climbing using an active tail are explored. The design, fabrication, analysis and test of the robot are reported. Experimental results of walking and climbing up to 85deg sloped acrylic surfaces as well as successful steering and peeling mechanism tests are demonstrated. The potential applications foreseen for this kind of robots are inspection, repair, cleaning, and exploration