Open AccessMuscle‐Inspired Linear Actuators by Electrochemical Oxidation of Liquid Metal Bridges
Author(s) -
Liao Jiahe,
Majidi Carmel
Publication year - 2022
Publication title -
advanced science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.388
H-Index - 100
ISSN - 2198-3844
DOI - 10.1002/advs.202201963
Subject(s) - actuator , materials science , artificial muscle , voltage , liquid metal , work (physics) , eutectic system , nanotechnology , mechanical engineering , computer science , optoelectronics , electrical engineering , composite material , alloy , engineering , artificial intelligence
Progress in artificial muscles relies on new architectures that combine soft matter with transduction mechanisms for converting controlled stimuli into mechanical work. Liquid metal, in particular eutectic gallium–indium (EGaIn), is promising for creating an artificial muscle since it is intrinsically deformable and capable of generating significant force and shape change through low voltage stimulation. In this work, a muscle‐inspired structure for designing liquid metal actuators is presented, where EGaIn droplets are configured with copper pads to linearly contract. By theory and experiments, it is demonstrated that this design enables higher work densities and stress, making it a favorable actuator at smaller length scales. Furthermore, higher frequency (up to 5 Hz) operation is achieved by prestretching an antagonistic pair of actuators, where energy bistability enables fast‐switching actuation. Overall, this muscle‐inspired architecture shows a unique combination of low voltage operation, higher energy density at smaller scales, structural scalability, and higher frequency actuation.