High Strength Inflatable Pouch Anchors

Abstract

Anchoring is an important capability for mobile robots to conserve power, survey an area, or deploy a payload. However, the careful placement of an anchor in unstructured environments requires a great deal of dexterity, perception, and planning. Furthermore, many of the reversible adhesives that may be used for anchoring are surface-dependent. We introduce inflatable pouch anchors as a versatile, low-power, and easy-to-position technology for anchoring in natural surfaces. By using negative space such as gaps and cracks with a flexible pouch, the challenge of placing an anchor is greatly simplified. We used a compressed CO$_2$ canister to supply pressure, and a three-way normally-closed valve to allow for multiple uses. We tested the anchor with high friction interfaces such as microspines and gecko-inspired adhesives. We validated the performance with tests on smooth acrylic, sandpaper, manufactured rock, and natural rock. The 425 g anchor actuated at an internal pressure of 105 kPa held over 700 N when anchored in natural rock with a microspine interface.