Selectively Stiffening Garments Enabled by Cellular Composites

Abstract

Recent efforts on wearable robots have focused on augmenting the motor performance and/or protecting the wearer's body with lightweight structures. However, providing human‐scale force and structural stiffness usually conflicts with the wearability. Inspired by sandwich‐structured composites with high structural strengths, widely employed in both nature and man‐made structures, a mechanism of selectively stiffening garments (SSGs) utilizing anisotropic cellular cores and rubber‐laminated face sheets is proposed. While the proposed mechanism shows a high compliance allowing for conformity to the wearer's body when unjammed, it provides a significantly high force density when jammed, compared to conventional jamming methods, allowing for the ability to adjust mechanical properties based on the designs and materials. In this paper, various designs of the sandwich jamming structures for the SSGs with analytical characterizations and experimental validations are introduced. Potential applications for force and motion assistance are also demonstrated and impacted mitigation.

Soft modularized robotic arm for safe human–robot interaction based on visual and proprioceptive feedback

“…It is sometimes useful to recognize objects or humans in proximity that approach to the robot. One possible solution is to use the organogel channels as a proximity sensor by measuring the change in capacitance (Navarro et al, 2021; Kwon et al, 2022). In this way, the robot will be able to more proactively respond to any possible contacts or collisions in advance.…”

Shape memory meta-laminar jamming actuators fabricated by 4D printing

“…Kwon et al [33] created a sandwich jamming construction that consists of a rubberlaminated front sheet and an anisotropic cellular core. When the structure was not jammed, the light anisotropic core's low bending modulus allowed for excellent structural compliance, but when jamming occurred, it became extremely stiff.…”

Multi‐Modal Modular Textile Sensor for Physical Human–Robot Interaction Using Band‐Stop Filters

“…[10][11][12] Sensors that can be used with robotic skin measure various stimuli, such as proximity, force, and human touch, on the surface. Proximity sensors, which detects an object before physical contacts, were developed using inductive, [13][14][15] capacitive, [12,[16][17][18] and optical [19][20][21][22] mechanisms. Force sensors were implemented by resistive [23][24][25][26][27][28][29][30][31][32][33][34][35][36] and capacitive [37][38][39][40][41][42][43] mechanisms to measure contact forces, and touch sensors were developed using a capacitive mechanism.…”