In-Hand Manipulation With a Simple Belted Parallel-Jaw Gripper

Gregory Xie, Rachel M. Holladay, Lillian Chin, Daniela Rus

Abstract: Many manipulation tasks require task-specific grasps that may initially be unavailable, requiring the robot to transition from grasp to grasp. Current approaches to in-hand manipulation often involve complex hardware or algorithms, which limits their use in real-world tasks. In this work, we present an integratedapproach to in-hand manipulation through Belt Orienting Phalanges (BOP), maximizing gripper capability by considering both hardware and algorithm design. BOP is a parallel-jaw gripper where each finger has two sets of belts. Together, the two fingers' belts can impart forces and torques on to a grasped object to control its roll, pitch and translation. These movements form the basis of motion primitives that can be sequenced together for in-hand manipulation of objects as well as for complex motions such as syringe actuation and fingernail-style lifting. We characterize these motion primitives, develop a grasp-to-grasp motion planner, and demonstrate the potential of BOP through the real-world example of screwing a light bulb into a socket.