Researchers from Australia’s University of Wollongong (UOW) will be joining a global collaboration that will be developing an exciting new material.
According to a recent press release, UOW researchers at the ARC Centre of Excellence for Electromaterials Science (ACES) have joined with international partners from the USA, China and South Korea to develop sheath-run artificial muscles (SRAMs).
This can be used to create intelligent materials and fabrics that react by sensing the environment around them.
About the initiative
It builds on the work done by researchers from the University and their international colleagues over the past 15 years.
Their work includes invention of several types of strong, powerful artificial muscles using materials ranging from high-tech carbon nanotubes (CNTs) to ordinary fishing line.
The latest version of the muscles feature a sheath around a coiled or twisted yarn, which contracts or “actuates” when heated, and returns to its initial state when cooled.
The outside sheath is similar to a close-fitting sock and absorbs energy to drive actuation of the muscle. The muscles can also operate by absorbing moisture from their surroundings.
Sheath-run artificial muscles
The new SRAMs are made from common natural and man-made fibres like cotton, silk, wool and nylon, which are cheap and readily available.
According to the ACES Chief Investigator, the team wanted to improve upon its previous artificial muscle work, which relied on coiling and twisting more sophisticated materials like carbon nanotube (CNT) yarn.
Although CNTs make wonderful artificial muscles, it is a very expensive product. The team’s latest work utilises inexpensive, commercially available yarns with a CNT polymer coating for the sheath.
Previously, energy was being applied to the entire muscle. However, only the outer part of the fibre was responsible for actuation.
By placing a sheath on the muscle, the energy can be focused on the outer part of the fibre only. This can then convert the input energy more quickly and efficiently.
Possible applications for SRAMs
There are several and diverse possible applications for SRAMs as explained by ARC-DECRA Fellow and lead Australian researcher Dr Javad Foroughi.
Talking about artificial muscles is not just about the technology being a replacement for muscles in the body.
These muscles also offer some exciting opportunities for technologies where the artificial muscles intelligently actuate by sensing their environment.
For one, these muscles may be woven into comfort-adjusting textiles that cool in summer and warm in winter, depending on their exposure to temperature, moisture such as sweat, and sunlight.
It may also be used as smart controlled drug release devices for localised drug delivery through the actuation of valves that control the flow of liquids depending on their chemical composition or temperature.
Collaboration is key
The ACES Director described this work as an excellent example of the importance of global collaboration in delivering efficient, effective and high impact advances in research and innovation.
The success of the Centre’s work on artificial muscles is the result of the highly skilled researchers being important contributors to a diverse and multidisciplinary team assembled from across the globe.
Building these links enables the realisation of exciting new technologies.
The project’s collaborators include the University of Wollongong, Australia; the University of Texas at Dallas, USA; Donghus University, China; and Hanyang University, South Korea.
