Open AccessLighter and Stronger: Cofabricated Electrodes and Variable Stiffness Elements in Dielectric Actuators
Author(s) -
Piskarev Yegor,
Shintake Jun,
Ramachandran Vivek,
Baugh Neil,
Dickey Michael D.,
Floreano Dario
Publication year - 2020
Publication title -
advanced intelligent systems
Language(s) - English
Resource type - Journals
ISSN - 2640-4567
DOI - 10.1002/aisy.202000069
Subject(s) - stiffness , actuator , materials science , electrode , elastomer , dielectric , bending , composite material , bending stiffness , deformation (meteorology) , structural engineering , mechanical engineering , optoelectronics , electrical engineering , engineering , physics , quantum mechanics
The inherent compliance of soft robots often makes it difficult for them to exert forces on surrounding surfaces or withstand mechanical loading. Controlled stiffness is a solution to empower soft robots with the ability to apply large forces on their environments and sustain external loads without deformations. Herein, a compact, soft actuator composed of a shared electrode used for both electrostatic actuation and variable stiffness is described. The device operates as a dielectric elastomer actuator, while variable stiffness is provided by a shared electrode made of gallium. The fabricated actuator, namely variable stiffness dielectric elastomer actuator (VSDEA), has a compact and lightweight structure with a thickness of 930 μm and a mass of 0.7 g. It exhibits a stiffness change of 183×, a bending angle of 31°, and a blocked force of 0.65 mN. Thanks to the lightweight feature, the stiffness change per mass of the actuator (261× g −1 ) is 2.6 times higher than that of the other type of VSDEA that has no shared electrode.