Microspine-Rubber Composite for High Friction on Smooth, Rough, and Wet Surfaces
Tech ID: 32585 / UC Case 2018-619-0
Traction is an important consideration for all modes of mobility. Especially as robotic technologies advance and robots move out of research facilities and into the real world, their function hinges on traction; they must be able to grip a variety of surfaces (e.g. smooth or rough) in a variety of conditions (e.g. dry or wet). As is often the case, nature offers solutions for this obstacle, such as retractable claws or spines. Insects in particular are able to navigate many surfaces and conditions using microspines that are employed only when necessary. Microspines have been demonstrated in small-scale vertical climbing robots, but they lack the dynamic quality of biological microspines and are relegated to low normal force scenarios. There is much potential for variable microspine applications in large normal force situations on the feet or wheels of mobile robots.
Researchers at the University of California, Santa Barbara, have developed a microspine-rubber composite for high friction on various surfaces (smooth or rough, dry or wet). The two key elements of the composite are a flat surface of high-friction rubber and thin, cylindrical microspines. The microspines protrude at an angle through cutouts in the rubber, but are supported only at their bases. This design allows each cantilevered microspine to easily flex about its base when a load is primarily perpendicular to its axis, yet remain stiff when loaded axially, which mimics the dynamic qualities of biological microspines. This technology allows the composite to support large loads (greater than 75 N) with a high coefficient of friction on both smooth and rough surfaces (µ > 1.1). Furthermore, the composite does not damage relatively soft, smooth surfaces, like wood flooring.
- Application of bioinspired microspines to larger loads
- High friction on various surfaces (smooth or rough) in various conditions (wet or dry)