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Updated: Nov 4, 2025

Microfluidic Preparation of Liquid Crystalline Elastomer Actuators

Microfluidic Preparation of Liquid Crystalline Elastomer Actuators

Published on: May 20, 2018

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

Arda Kotikian¹, Javier M Morales², Aric Lu^1,3

¹John A. Paulson School of Engineering and Applied Sciences and Wyss Institute for Biologically Inspired Engineering, Harvard University, Cambridge, MA, 02138, USA.

Advanced Materials (Deerfield Beach, Fla.)

|May 31, 2021

Summary

This summary is machine-generated.

Researchers developed programmable liquid crystal elastomer (LCE) actuators using 3D printing. These self-sensing actuators offer precise control for complex, shape-changing applications.

Keywords:

3D printing actuators liquid crystal elastomers shape morphing

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Area of Science:

Materials Science
Robotics
Soft Matter Physics

Background:

Developing advanced actuators with integrated sensing and control is crucial for next-generation robotics and adaptive materials.
Liquid Crystal Elastomers (LCEs) offer unique stimulus-responsive properties for actuation.
Achieving programmable, closed-loop control in soft actuators remains a significant challenge.

Purpose of the Study:

To report the programmable assembly of innervated LCE actuators (iLCEs) with prescribed contractile actuation, self-sensing, and closed-loop control.
To demonstrate a core-shell 3D printing method for fabricating these advanced actuators.
To investigate the thermal response and self-sensing capabilities of iLCEs under Joule heating.

Main Methods:

Utilizing extrusion-based direct ink writing for core-shell 3D printing of coaxial filamentary features.
Aligning the director of the LCE shell along the print path for programmed actuation.
Programming, measuring, and modeling the thermal response and resistance changes during Joule heating.
Implementing closed-loop control systems to regulate iLCEs under varying loads.

Main Results:

Successfully fabricated iLCE fibers with programmed thermal response and self-sensing capabilities.
Quantified simultaneous changes in fiber length and resistance during Joule heating.
Demonstrated stable closed-loop control of iLCEs even under significant external perturbations.
Fabricated complex iLCE architectures exhibiting programmed 3D shape change with closed-loop control.

Conclusions:

Core-shell 3D printing enables the creation of sophisticated iLCEs with integrated actuation and self-sensing.
The developed iLCEs exhibit reversible, high-energy actuation and reliable resistive feedback for precise control.
This technology paves the way for advanced soft robotic systems and adaptive materials with programmable functionalities.