Issue 3, 2020

Torsional artificial muscles


Large stroke torsional actuators are the newest class of artificial muscle technology that produces rotary motion or generate torque in response to various stimuli. A number of materials comprising twisted fibres or filaments have been shown to display high degrees of reversible untwist and retwist under various experimental conditions such as heating, electrochemical charging, chemical absorption or photonic excitation. Torsional actuators are of potential application in areas that include microfluidic mixing, microsensors, photonic displays, and energy-harvesting devices. Furthermore, the torsional actuation in fibres can be translated into a linear, or tensile, actuation when the fibres are formed into coils. These coil tensile artificial muscles are of potential use in soft and wearable robotics, medical devices and prosthetics. This review will provide a comprehensive overview of torsional actuators constructed from different functional materials, their actuating mechanism, potential applications, and their current limitations. The review will conclude with recent developments and future trends of torsional actuators as well as critical issues that need to be addressed and resolved.

Graphical abstract: Torsional artificial muscles

Article information

Article type
Review Article
12 Sep 2019
24 Oct 2019
First published
24 Oct 2019

Mater. Horiz., 2020,7, 667-693

Torsional artificial muscles

S. Aziz and G. M. Spinks, Mater. Horiz., 2020, 7, 667 DOI: 10.1039/C9MH01441A

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity