Self-Sensing, Optoelectronic Artificial Muscle Tissues for Energy Efficient Locomotion in Soft Machi
Abstract
This research program will develop soft artificial muscle tissues capable of high power density, energy-efficient actuation for unte,thered locomotion in soft, bioinspired machines. The 3D printable, artificial muscle tissues proposed here involve the design and fa,brication of optoelectronically-stimulated, liquid crystal elastomer and ionogel composite fibers. Bundles of individually-addressab,le artificial muscle fibers are readily organized into large-scale artificial muscle tissues with distributed actuation and proprioc,eptive capabilities. The proposed artificial muscle tissues will provide high force, high strain, and truly contractile actuation in, a high power density, energy-efficient design. We will fill three key technological gaps for designing self-sensing artificial musc,les for robust, reliable, and bioinspired locomotion in untethered soft robots. First, most soft matter actuators suffer from key pe,rformance and hardware trade-offs. Soft actuators - including hydraulic, electrostatic and thermomechanical actuators - typically e,xhibit low actuation frequency and low energy efficiency compared to traditional robot actuators and motors. Liquid crystal elastome,r actuators (LCEAs) are a popular soft actuator for driving high strain, high force actuation. However, current varieties do not off,er energy efficient performance. Phototropic LCEAs can theoretically offer a more energy efficient design than thermotropic varietie,s, but requirements for remote light sources and short penetration depths of incident optical stimuli are major barriers to their pr,actical adoption. We will develop photoactuated LCEA fibers with internal cores of deformable ionogel waveguides. The waveguides wil,l facilitate propagation of light along the length of the fiber to achieve a more energy-efficient, high work capacity LCEA design.,We will develop new 3D printing methods and materials to fabricate the LCEA fibers with internal waveguide cores. Second, current LC,EAs exhibit low actuation bandwidths, which limit their ability to facilitate practical locomotion speeds in untethered soft robots., We will demonstrate an energy-efficient approach to improve actuation bandwidth in the artificial muscle fibers using electrostatic,ally driven isotropic-nematic transitions. We will design new materials and testbeds to demonstrate our novel approach for simplifyi,ng LCEA relaxation and increasing LCEA actuation frequency. Finally, we will use multimaterial printing methods to fabricate artific,ial muscle tissues and untethered soft robots capable of terrestrial and underwater locomotion. Overall, this proposal will achieve, three key innovations: (1) 3D print photoactuatable, core-shell liquid crystal elastomer fibers with internal ionogel waveguides; (,2) electrostatically control cis-to-trans isomerization in azobenzene-functionalized liquid crystal elastomers for rapid reversibili,ty; and (3) 3D print soft robotic muscle tissue with distributed sensorimotor capabilities for untethered terrestrial and underwater, locomotion.This proposal introduces new materials and manufacturing methods to 3D print artificial muscle tissues and novel soft ro,bot embodiments. The materials, 3D printing methods, and actuators developed by this program will pioneer novel capabilities in appl,ications of broad naval interest, spanning, robotics, wearable technologies, bioinspired materials, and more.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- May 16, 2022
- Source ID
- N000142212447
Entities
People
- Ryan L Truby
Organizations
- Northwestern University
- Office of Naval Research
- United States Navy