A Soft Gripper with Granular Jamming and Electroadhesive Properties

Abstract

In recent years, there has been a growing interest in the development of universal soft grippers that can handle objects of varying form factors (including flat objects), surface conditions (including moistened or oily objects), and mechanical properties (deformable and fragile). Yet, there is no single gripper that can gently grip objects with such a wide range of properties. Herein, a soft gripper that combines granular jamming (GJ) and electroadhesion (EA) to gently grasp and release a large set of diverse objects is presented. The gripper can operate in GJ mode only, in EA mode only, or in a combination mode that simultaneously activates GJ and EA. In GJ mode, the gripper can grasp objects with different surface properties, lift objects 38 times its own weight using negative pressure, and release objects by applying positive pressure, but has difficulty in handling flat and fragile objects. In EA mode, the gripper can manipulate flat and fragile objects but encounters difficulties with different surface properties such as oily or moisture. In the combination mode, the gripper can generate grasping forces up to 35% higher than in the GJ mode for all object sizes and certain shapes such as a cylinder. An interactive preprint version of the article can be found here: https://doi.org/10.22541/au.166937296.61200374/v1.

Injection Molding of Liquid Metal by Harnessing Nonstick Molds

“…Electroadhesion is the adhesive force generated by applying electric fields emanating from a surface in contact with a target object. Electroadhesion helps to handle soft and fragile objects using lightweight and high-compliance electrodes. − As shown in Figure A, two interdigitated electrodes were printed on 40 μm thick TPU and encapsulated with Ecoflex 0030. We applied a high voltage (up to 4 kV, 40 V/μm) between the two interdigitated electrodes.…”

A fast actuated soft gripper based on shape memory alloy wires

“…or put additional pressure on the target when grasping objects [10,11]. As a result, researchers begin to explore softer, more efficient and more convenient grasping options.…”

Automated Grasp Planning and Finger Design Space Search Using Multiple Grasp Quality Measures

“…Apart from multi-function fingertips, other solutions for flexible gripping include the following: universal gripping consisting of adaptive multi-fingered hands [2][3][4], soft fingertips [5], shape morphing fingertips [6], granular jamming [7], gripper exchange systems [8], modular gripping [9] consisting of re-configurable jaws designed based on closure analysis [10], and multi-function finger design wherein the design of the fingertip is chosen to handle multiple objects [11]. Multi-function fingers are cheaper, more effective, and more reliable than tool-changing systems and rotary wrist mechanisms.…”