ABI's Biomimetics Lab, where the research group’s work on electric charges has helped create groundbreaking inventions.
Biomimetics involves drawing inspiration from nature to develop new technologies. Living organisms and natural phenomena have certain behaviours and properties which let them exist in harmony with the surrounding environment.
By understanding these natural processes, we are developing technologies to venture into new territories.
From coupling electric charge to soft rubbery materials, our work led us to wearable stretchy sensors and soft energy harvesters. These can sense and collect power from human movement.
Our spin-out company StretchSense then emerged, which now employs over 20 staff serving 200 business-to-business customers worldwide.
StretchSense is licensing the lab’s sensing and energy harvesting technology for wearable applications.
Since the emergence of StretchSense, our lab has been exploring something quite different that will lead to a new way of controlling electrons: rubbery switches that turn electric charges on and off with stretch. We have discovered how to couple these switches with polymer artificial muscles to control them locally, similar to a neural ganglion.
A further challenge is coupling these switches to real muscles.
Explore more: StretchSense.
Can we use our switches to build strain sensitive devices that can pump medication subcutaneously or directly assist natural pumps such as the heart? Can we use these switches like the axons of nerves to restore muscle activity? We are at the start.
Soft electronics for robots
A challenge in soft robotics is incorporating compatible driving electronics into soft structures. Conventional electronics are rigid and dense. To make entirely soft and autonomous robots, soft low density electronics are needed.
To meet this challenge, the Biomimetics Lab developed the dielectric elastomer switch (DES) – a flexible electrode having strain-dependent conductivity. The DES controls charge to soft dielectric elastomer actuators, also known as artificial muscles. This means coupled switches and artificial muscles make up smart actuator networks that we can use to rhythmically drive our biomimetic robots.
The video shown here showcases our crawling caterpillar-like robot ‘Trevor’. The electronics-free robot is fed a DC charge from the copper tracks through contacts on its feet. A signal processing unit of artificial muscles and DES – the only materials are soft polymer and carbon – generates an oscillating voltage, which creates rhythmical movement in the actuators making Trevor crawl forward.
For more great videos of our biomimetic robots and other projects, see our YouTube page.
Soft wearable game controller
Conventional human-computer interfaces are very restrictive, because they are designed to be operated on a desktop, by a person sitting in a chair. As a consequence, users are desk-bound, instead of enjoying an immersive interaction.
We have addressed these limitations with a wearable game controller for the popular 3D computer game ‘Doom’. The glove-shaped device captures finger movements with soft stretch sensors to change weapons, and uses an accelerometer for left and right, backward and forward movement. Players can now interact with Doom through body motion, which adds an exciting physical component to the game experience.
Programmable rubber keyboard
This novel sensing method uses multiple sensing frequencies to target different regions of the same dielectric elastomer. It simultaneously detects position and pressure using only a single pair of connections. The dielectric elastomer is modelled as an RC transmission line and its internal voltage and current distribution are used to determine localised capacitance changes resulting from contact and pressure.
No modifications of the sensing hardware or the dielectric elastomer are required to increase the number of locations. This sensing method is demonstrated on a multi-touch musical keyboard made from a single low cost carbon-based dielectric elastomer with four distinct musical tones mapped along a length of 0.1m.
The Biomimetics Lab is host to the Southern Hemisphere’s only human-powered submarine. The fin-propelled ‘Taniwha’ outdid expectations at the 2015 International Submarine Race in Maryland, USA. With a top speed of 3.65 knots, Taniwha finished first in its class and got an innovation award for its unique automated ballasting system.
In 2016 the sub won the overall award at the European International Submarine Races (EISR) in Gosport, England. The submarine completed the races with 100% reliability and a new top speed of 4.6 knots.
Taniwha now has its sights on the 4th EISR in July 2018.
For more information, visit Taniwha.
Explore more of our research: Biomimetics Lab YouTube page.
- Switzerland: EMPA and EPFL
- UK: Bristol Robotics Lab
- US: US Army Research Lab