Self-propelled, endlessly programmable artificial cilia

For years, scientists have been trying to engineer artificial cilia for miniature robotic systems that can perform complex motions. Multi-step fabrication processes and varying stimuli are required to create the complex movements needed to build these smaller-than-human-hair microstructures.

The Harvard John A. Paulson School of Engineering and Applied Sciences has developed a single-material, single-stimuli microstructure that can outmaneuver even living cilia. These structures could be used for a wide range of applications, including soft robotics, biocompatible medical devices, and even dynamic information encryption.

The research is published in a journal.

The Amy Smith Berylson Professor of Materials Science said that innovations in adaptive self-regulated materials that are capable of a diverse set of programmed motions represent a very active field.

Aizenberg and her team designed a pillar made of a single material that could be used to move reconfigurable structural elements. When light hits the structure, the building blocks realign and the shape changes.

There are two things that happen when this shape change occurs. The spot where the light hits becomes transparent, allowing the light to penetrate further into the material. As the material changes and the shape moves, a new spot on the pillar is exposed to light, causing it to change shape as well.

The feedback loop propels the structure into motion.

The internal and external feedback loop gives us a self-regulating material. Shucong Li, a graduate student in the Department of Chemistry and Chemical Biology at Harvard and co-first author of the paper, said that once you turn the light on, it does all its own work.

The material snaps back to its original shape when the light goes off.

These simple structures are reconfigurable and tunable because of the material's twists and motions. The researchers used a model and experiments to show how the material can be changed.

We showed that we can program the dance by tailoring a range of parameters, including illumination angle, light intensity, molecule alignment, microstructure geometry, temperature, and irradiation intervals and duration.

The research team demonstrated how the pillars interact with each other as part of an array.

When these pillars are grouped together, they interact in complex ways because each pillar casts a shadow on its neighbor.

The vast design space for individual and collective motions is potentially useful for soft robotics, micro-walkers, sensors, and robust information encryption systems.

More information: Shucong Li et al, Self-regulated non-reciprocal motions in single-material microstructures, Nature (2022). DOI: 10.1038/s41586-022-04561-z Journal information: Nature Citation: Self-propelled, endlessly programmable artificial cilia (2022, May 6) retrieved 6 May 2022 from https://phys.org/news/2022-05-self-propelled-endlessly-programmable-artificial-cilia.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.