Innervated, Self-Sensing Liquid Crystal Elastomer Actuators with Closed Loop Control

Arda Kotikian; Javier M Morales; Aric Lu; Jochen Mueller; Zoey S Davidson; J William Boley; Jennifer A Lewis

doi:10.1002/adma.202101814

Innervated, Self-Sensing Liquid Crystal Elastomer Actuators with Closed Loop Control

Adv Mater. 2021 Jul;33(27):e2101814. doi: 10.1002/adma.202101814. Epub 2021 May 31.

Authors

Arda Kotikian¹, Javier M Morales², Aric Lu^{1

3}, Jochen Mueller¹, Zoey S Davidson¹, J William Boley², Jennifer A Lewis¹

Affiliations

¹ John A. Paulson School of Engineering and Applied Sciences and Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, MA, 02138, USA.
² Mechanical Engineering Department, Boston University, Boston, MA, 02215, USA.
³ Biological Engineering Division, Draper Laboratory, Cambridge, MA, 02139, USA.

PMID: 34057260
DOI: 10.1002/adma.202101814

Abstract

The programmable assembly of innervated LCE actuators (iLCEs) with prescribed contractile actuation, self-sensing, and closed loop control via core-shell 3D printing is reported. This extrusion-based direct ink writing method enables coaxial filamentary features composed of pure LM core surrounded by an LCE shell, whose director is aligned along the print path. Specifically, the thermal response of the iLCE fiber-type actuators is programmed, measured, and modeled during Joule heating, including quantifying the concomitant changes in fiber length and resistance that arise during simultaneous heating and self-sensing. Due to their reversible, high-energy actuation and their resistive feedback, it is also demonstrated that iLCEs can be regulated with closed loop control even when perturbed with large bias loads. Finally, iLCE architectures capable of programmed, self-sensing 3D shape change with closed loop control are fabricated.

Keywords: 3D printing; actuators; liquid crystal elastomers; shape morphing.

Abstract

Grants and funding