Anthropometric Robotic Hand for Pressurized Glove Torque Measurement

Abstract

While robotic hands have been developed for tasks such as manipulation and grasping, their potential as tools for evaluation of engineered products — particularly compliant structures that are not easily modeled — has not been broadly studied. In this research, a low-cost anthropometric robotic hand is introduced that is designed to characterize glove stiffness in a pressurized environment. The interaction with the compliant pressurized glove provides unique performance requirements and design constraints. The anthropometric robotic hand was designed to mimic the human hand in a configuration corresponding to the neutral position in zero gravity, including the transverse arch, longitudinal arch, and oblique flexion of the rays. The resulting robotic hand also allows for realistic donning and doffing of the prototype glove, its pressurization, and torque testing of individual joints. Solid modeling and 3D printing enabled the rapid design iterations necessary to work successfully with the compliant pressure garment. An instrumentation and data processing method was used to calculate the required actuator torque at each finger's knuckle joint. The performance of the robotic hand was experimentally demonstrated with a prototype spacesuit glove at different levels of pressure, followed by a statistical repeatability analysis. The reliable measurement method validated the pressure-induced stiffening. The resulting robotic design and testing method provide an objective and systematic way of evaluating the performance of compliant gloves.