Development of universal jamming gripper with a force feedback mechanism

A universal jamming gripper (UJG) that consists of a single mass of granular material encased in an elastic membrane, and a vacuum pump that extracts air can passively conform to a wide variety of arbitrarily shaped objects, and then vacuum-harden to grip the objects rigidly. In this study, an elastic membrane is first filled with various materials and a material suitable for the UJG is determined by verifying the grip force. Next, the optimal fill volume of the material is determined experimentally. Furthermore, it is shown experimentally that an appropriate press force exists for generating maximum grip force of the UJG. Finally, a force feedback mechanism of the UJG is developed for generating the appropriate press force, and its effectiveness is evaluated by experiment.