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Title: Soft mobile robots driven by foldable dielectric elastomer actuators

Abstract

A cantilever beam with elastic hinge pulled antagonistically by two dielectric elastomer (DE) membranes in tension forms a foldable actuator if one DE membrane is subject to a voltage and releases part of tension. Simply placing parallel rigid bars on the prestressed DE membranes results in enhanced actuators working in a pure shear state. We report design, analysis, fabrication, and experiment of soft mobile robots that are moved by such foldable DE actuators. We describe systematic measurement of the foldable actuators and perform theoretical analysis of such actuators based on minimization of total energy, and a good agreement is achieved between model prediction and measurement. We develop two versions of prototypes of soft mobile robots driven either by two sets of DE membranes or one DE membrane and elastic springs. We demonstrate locomotion of these soft mobile robots and highlight several key design parameters that influence locomotion of the robots. A 45 g soft robot driven by a cyclic triangle voltage with amplitude 7.4 kV demonstrates maximal stroke 160 mm or maximal rolling velocity 42 mm/s. The underlying mechanics and physics of foldable DE actuators can be leveraged to develop other soft machines for various applications.

Authors:
; ; ; ;  [1]
  1. State Key Laboratory for Strength and Vibration of Mechanical Structures and School of Aerospace, Xi'an Jiaotong University, Xi'an 710049 (China)
Publication Date:
OSTI Identifier:
22598880
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 8; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ACTUATORS; DESIGN; DIELECTRIC MATERIALS; ELASTICITY; ELASTOMERS; ELECTRIC POTENTIAL; MEMBRANES; MINIMIZATION; ROBOTS; ROLLING; SPRINGS

Citation Formats

Sun, Wenjie, Liu, Fan, Ma, Ziqi, Li, Chenghai, and Zhou, Jinxiong, E-mail: jxzhouxx@mail.xjtu.edu.cn. Soft mobile robots driven by foldable dielectric elastomer actuators. United States: N. p., 2016. Web. doi:10.1063/1.4960718.
Sun, Wenjie, Liu, Fan, Ma, Ziqi, Li, Chenghai, & Zhou, Jinxiong, E-mail: jxzhouxx@mail.xjtu.edu.cn. Soft mobile robots driven by foldable dielectric elastomer actuators. United States. doi:10.1063/1.4960718.
Sun, Wenjie, Liu, Fan, Ma, Ziqi, Li, Chenghai, and Zhou, Jinxiong, E-mail: jxzhouxx@mail.xjtu.edu.cn. 2016. "Soft mobile robots driven by foldable dielectric elastomer actuators". United States. doi:10.1063/1.4960718.
@article{osti_22598880,
title = {Soft mobile robots driven by foldable dielectric elastomer actuators},
author = {Sun, Wenjie and Liu, Fan and Ma, Ziqi and Li, Chenghai and Zhou, Jinxiong, E-mail: jxzhouxx@mail.xjtu.edu.cn},
abstractNote = {A cantilever beam with elastic hinge pulled antagonistically by two dielectric elastomer (DE) membranes in tension forms a foldable actuator if one DE membrane is subject to a voltage and releases part of tension. Simply placing parallel rigid bars on the prestressed DE membranes results in enhanced actuators working in a pure shear state. We report design, analysis, fabrication, and experiment of soft mobile robots that are moved by such foldable DE actuators. We describe systematic measurement of the foldable actuators and perform theoretical analysis of such actuators based on minimization of total energy, and a good agreement is achieved between model prediction and measurement. We develop two versions of prototypes of soft mobile robots driven either by two sets of DE membranes or one DE membrane and elastic springs. We demonstrate locomotion of these soft mobile robots and highlight several key design parameters that influence locomotion of the robots. A 45 g soft robot driven by a cyclic triangle voltage with amplitude 7.4 kV demonstrates maximal stroke 160 mm or maximal rolling velocity 42 mm/s. The underlying mechanics and physics of foldable DE actuators can be leveraged to develop other soft machines for various applications.},
doi = {10.1063/1.4960718},
journal = {Journal of Applied Physics},
number = 8,
volume = 120,
place = {United States},
year = 2016,
month = 8
}
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