A unique control system for a 3D-printed prosthetic hand is showing great promise in performing intricate, natural finger motions with a high degree of accuracy.
The prosthetic hand, recently tested by a group of seven participants, needs minimal training to master. The technology, experts hope, will greatly improve the quality of life of amputees.
A 'user-friendly' system
Controlled by electrical signals from a human's muscles, the test participants, including an upper-limb amputee, were able to test the system's full range of motions.
In the US, there are approximately 540,000 upper-limb amputees.
50% to 60% of these use prosthetic hands daily in order to try to improve their quality of life, so it is a high priority for prosthesis makers to continue to make their products as comfortable to use as possible.
Overcoming tech limitations
While advances for prosthetics are coming fast, a lot of work can still be done to improve the usability and affordability of existing and upcoming models.
Commercially available myoelectric prosthetic — which typically pick up electric signals from muscles — can cost between $25,000 and $75,000. They also usually require a lot of training to be able to use effectively.
To overcome these limitations, Akira Furui and his colleagues from Hiroshima University created a more adaptable 3D-printed prosthetic hand.
It has five independently driven fingers and uses a unique control system powered by "muscle synergy theory", which allows for more complex movements.
The system essentially allows different fingers to be moved more effectively than existing models, all at the same time. This makes it much easier to perform everyday movements, such as holding a notebook or holding a plastic bottle.
By using the new system, participants were able to perform 10 different finger motions with over 90% accuracy.
The team's work has a great deal of potential for the future of prosthesis.
One of the next areas of focus for the researchers is alleviating the fatigue felt by users in the prolonged use of the prosthetic system.