Rotary Microspine Rough Surface Mobility

The Jet Propulsion Laboratory is developing a class of lightweight, highly mobile, crash-proof robots for reconnaissance and security applications. Arrays of independently compliant rotary microspines are used to build wheels that enable the robots to climb stairs, mount curbs, and climb rough vertical walls. This study presents many improvements to the rotary microspine wheels and several new configurations of the robotic platforms, including miniaturized robots weighing less than 10 g. New microspine flexure materials are presented including viscoelastic flexures that dampen the impact of individual hook elements, and mass-manufacturable microspines made using a single cast process over steel wire in place of elastic flexures. Rapid iteration of microspine designs was done using shape deposition manufacturing and a single-wheeled test robot. This process allowed new wheel concepts to go from design to testing in just three days. In addition, new configurations of robots with a powered wheel in the tail have improved reliability and demonstrated new capabilities like climbing heavily painted curbs, climbing stairs with overhanging face angles, and vertical climbing of concrete block buildings as tall as six stories. These results are presented in this paper and in the accompanying video.