Special Issue on the Mechanics and Design of Robotic Hands

There has been a renewed interest in recent years to work towards robotic hands that are effective in addressing the needs of modern robotic systems. As robots increasingly move out of the lab and into unstructured environments, the need for hands designed to function under the uncertainty and wide range of conditions associated with those environments has become more pressing. This special issue focuses on papers that address the mechanics and practical design requirements associated with current grasping and manipulation applications, including systems that are lightweight, dexterous, mobile-friendly, inexpensive, robust to uncertainty, and durable. This special issue consists of nine papers from researchers around the globe. The scope of the papers spans a wide spectrum of approaches, from underactuated hands with a single or small number of actuators, to fully actu-ated hands with nearly human-like controllable degrees of freedom. A number of the hands incorporate some novel design feature that has yet to be examined in the context of robotic hands, including electrostatic clutches, twisted-string actuators, or novel underactuated mechanisms. Two of the hands present modular designs, with multiple uses of the same actuation module, and three of the hands attempt to achieve close anthropomorphism. Before getting to the papers that present complete hand designs, we begin the issue with two papers that focus on tendon-based actuation in robotic fingers. In Shirafuji, Ikemoto, and Hosoda, researchers from Osaka University examine the design of a tendon-driven finger modeled after the human index finger. Their design includes a mechanism to change the moment arm of tendons, as well as using branching tendons in order to mimic some of the features of the human finger. The second paper describes work by Inouye and Valero-Cuevas of the University of Southern California on the optimization of tendon routing in robotic fingers. By examining variations in asymmetry in joint centers, tendon routings, and maximal tendon tensions, among other parameters, they show that optimum tendon routing can produce fingers with force-production capabilities that can exceed that of human hands. The next three papers present the three hands developed under the US's Defense Advanced Research Projects Agency (DARPA) Autonomous Robotic Manipulation (ARM) program. While a large portion of the program focused on research involving developing algorithms and software for an existing robotic platform (i.e. the " software track "), three " hardware track " teams were selected to develop new robotic hands, which are described in this Special …