Abstractâ€”Established design and fabrication guidelines existÂ for achieving a variety of motions with soft actuators such asÂ bending, contraction, extension, and twisting. These guidelinesÂ typically involve multi-step molding of composite materialsÂ (elastomers, paper, fiber, etc.) along with specially designedÂ geometry. In this work we present the design and fabricationÂ of a robust, fiber-reinforced soft bending actuator where itsÂ bend radius and bending axis can be mechanically-programmedÂ with a flexible, selectively-placed conformal covering that actsÂ to mechanically constrain motion. Several soft actuators wereÂ fabricated and their displacement and force capabilities wereÂ measured experimentally and compared to demonstrate theÂ utility of this approach. Finally, a prototype two-digit end effectorÂ was designed and programmed with the conformalÂ covering to shape match a rectangular object. We demonstratedÂ improved gripping force compared to a pure bending actuator.Â We envision this approach enabling rapid customization of softÂ actuator function for grasping applications where the geometryÂ of the task is known a priori.
K.C. Galloway, P. Polygerinos, C. Walsh, R. Wood, â€œMechanically Programmable Bend Radius for Fiber-Reinforced Soft Actuators.â€ IEEE ICAR, 2013.
K.C. Galloway. Mechanically Programmed Soft Actuators with Conforming Sleeves. International Patent Pending, application PCT/US2014/060870.