A paralympian will test a new bionic hand built by Simon Fraser University (SFU) engineers on the world’s first Cybathlon in October.
Danny Letain, a parathlete who lost his arm during an occupational accident, will use SFU-developed bionic hand prosthesis when he competes at the Cybathlon slated on October 8.
Letain lost his arm 35 years ago and has since relied on prosthesis with only a pincer-like split hook that is strapped to his body to move the artificial limb. While it is durable and easy to maneuver, it is an energy-consuming process because the strap control feels unnatural.
With the bionic hand developed by SFU scientists, Letain can move his fingers and use various grip patterns.
“With this new system, it feels like I’m opening and closing my hand. The most exciting moment for me was feeling my left index finger and the little finger for the first time since my accident,” said Letain. “With the hook you don’t use those muscles at all. This system puts my mind to work in a whole new way.”
The bionic hand technology was initially developed in the biomedical engineering laboratory of Engineering Science Professor Carlo Menon to help rehabilitate stroke patients, but he realized that the technology would also have a great impact on amputees.
Rejection of some commercially available robotic prostheses is common because their usage is not intuitive. Only about a quarter of amputees utilize them because its control systems are not practical to use for carrying out everyday tasks.
Menon explained that these body-powered prostheses are controlled by electromyogram signals from residual limb contractions. The outdated system uses only two EMG signals from the limb, which the user needs to isolate in order to move particular muscles. Since it is not intuitive, users tend to become frustrated and forego use of any prosthetics.
The system developed by SFU engineers was applied on the bionic arm Bebionic3, which Steeper Prosthetics loaned to the engineers.
The technology is composed of armband pressure sensors inserted inside the prosthetic socket. These sensors then monitor the movements of the remaining muscles in Letain’s hands as he carries out intuitive tasks. Sensor data would be mapped via computer algorithms that would decode his intentions and eventually move the prosthesis. Intricate muscle movements are detected by sensors and converted into movements.
The new system gathers the input of data and makes real-time predictions. It also collects computer models to use for future activities. No new training on the part of the user is necessary.
“The more data you give it, the more it will learn,” said Mass Activity Sensor Strip (M.A.S.S.) research lead Lukas-Karim Merhi, an alumnus of SFU Engineering Science.
Research and Development Head of Barber Prosthetics Brittany Pousett said the new technology is breakthrough in electric prosthesis by allowing users to have increased range of movements.
Letain will compete in an obstacle course for individuals with powered arm prosthesis to carry out daily tasks like jar opening and bread slicing. A prototype was tested during a Cybathlon trial last July, and the team is now perfecting the system for the upcoming competition.
Letain would test the bionic hand when he competes at the first-ever Cybathlon tournament in Zurich this coming October. Organizers of Cybathlon from the Swiss Federal Institute of Technology hope to inspire innovators to come up with new technologies that would help people with disabilities win back their confidence.
Just recently, a group of researchers developed a brain implant that would allow movement of limb prosthesis brain signals sent through the exoskeleton.