| Title: |
Metric mechanics with nontrivial topology: Actuating irises, cylinders, and evertors. |
| Authors: |
Duffy, D; Javed, M; Abdelrahman, MK; Ware, TH; Warner, M; Biggins, JS |
| Publisher Information: |
American Physical Society (APS); Department of Physics Student; Department of Physics; Department of Engineering; //doi.org/10.1103/physreve.104.065004 |
| Publication Year: |
2021 |
| Collection: |
Apollo - University of Cambridge Repository |
| Subject Terms: |
4012 Fluid Mechanics and Thermal Engineering; 40 Engineering |
| Description: |
Liquid crystal elastomers contract along their director on heating and recover on cooling, offering great potential as actuators and artificial muscles. If a flat sheet is programed with a spatially varying director pattern, then it will actuate into a curved surface, allowing the material to act as a strong machine such as a grabber or lifter. Here we study the actuation of programed annular sheets which, owing to their central hole, can sidestep constraints on area and orientation. We systematically catalog the set of developable surfaces encodable via axisymmetric director patterns and uncover several qualitatively new modes of actuation, including cylinders, irises, and everted surfaces in which the inner boundary becomes the outer boundary after actuation. We confirm our designs with a combination of experiments and numerics. Many of our actuators can reattain their initial inner or outer radius upon completing actuation, making them particularly promising, as they can avoid potentially problematic stresses in their activated state even when fixed onto a frame or pipe. |
| Document Type: |
article in journal/newspaper |
| File Description: |
application/octet-stream; application/pdf |
| Language: |
English |
| Relation: |
https://www.repository.cam.ac.uk/handle/1810/331771 |
| DOI: |
10.17863/CAM.79220 |
| Availability: |
https://www.repository.cam.ac.uk/handle/1810/331771; https://doi.org/10.17863/CAM.79220 |
| Rights: |
All rights reserved ; http://purl.org/NET/rdflicense/allrightsreserved |
| Accession Number: |
edsbas.192C1408 |
| Database: |
BASE |