Tailorable Stiffness Lightweight Soft Robotic Materials with Architectured Exoskeleton

摘要

Extra-terrestrial and extra-vehicular activity (EVA) require extreme remote maneuverability and dexterity. At the same time, such robots must be lightweight with the possibility of on-site fabrication, retrofitting and assembly. This poses a difficult problem for traditional robotic systems and robotic materials, which are typically bulky, cannot exhibit large deformations for tight spaces and limited in their degrees of freedom. More significantly, such systems are incapable of being programmed to change their shape, function and properties once fabricated. This calls for soft robotic systems, which can reversibly deform to very large curvatures and typically lighter weight. However, traditional polymeric materials still suffer from lack of programmability in properties and shapes. Extracting multi-functionality is remains difficult. Here, we propose a new type of soft robotic material, which is made of a soft underlying polymer substrate with stiffer plate like material embedded on the surface overlapping with each other. The mutual sliding of these stiffer, protruding scale-like materials can be tailored via their geometry and tuned via their stiffness. We demonstrate the possibility of obtaining rapid stiffness gains under various loading conditions using a combination of analytical modeling, finite element (FE) simulations and lab scale experiments. Although materials selected are typical polymeric materials, our results are more general.