Pioneering techniques in the manufacture of artificial limbs continue to emerge
in Europe, and the SMARTHAND
('The smart bio-adaptive hand prosthesis') project has risen to the challenge.
Funded under the 'Nanotechnologies and nano-sciences, knowledge-based multifunctional
materials and new production processes and devices (NMP)' Thematic area of the
EU's Sixth Framework Programme (FP6), SMARTHAND has combined cutting-edge research
from various technologies with cognitive neuroscience. The result, an artificial
hand with the basic features of a real human hand, will help amputees to regain
sensation. Funding for SMARTHAND totals EUR 1.8 million.
What is unique about the sophisticated prototype artificial hand developed
by the SMARTHAND partners is that not only does it replicate the movements of
a real hand, but it also gives the user sensations of touch and feeling. The
researchers said the hand has 4 electric motors and 40 sensors that are activated
when pressed against an object. These sensors stimulate the arm's nerves to
activate a part in the brain that enables patients to feel the objects.
Robin af Ekenstam, an amputee from Sweden, was astounded by the result. An
aggressive tumour discovered on his right wrist forced Mr af Ekenstam to amputate
his limb in order to save his life and stop the cancer from spreading to the
rest of his body. He currently wears an electronic hook, but the problem with
this device is that he cannot feel what the hook does and handling is at a minimum.
'I am using muscles which I haven't used for years,' television news channel
euronews quoted Mr af Ekenstam, the first amputee to try the hand, as saying.
'That is very hard. But if you are able to control a movement, it is great.
It is a feeling that I have not had for a long time. And now I am also getting
the sensation back from small motors, which put pressure on certain spots on
my hand,' he said. 'When I grab something hard, then I can feel it in the fingertips,
which is strange, as I don't have them anymore. It's amazing.'
Led by Sweden's Lund University, the researchers continue to work on the sensory
feedback system within the robotic hand. The hurdle they need to cross is to
make the cables and electric motors smaller. Nanotechnology could help the team
iron out any problems. Specifically, they would implant a tiny processing unit,
a power source and a trans-skin communication method into the user of the hand
to optimise functionality.
Dr Göran Lundborg, an expert on how the brain controls hand movements,
told euronews: 'We know that by placing pressure sensors on the fingers of the
artificial hand, we can transpose that pressure signal to specific areas in
the skin of the remaining hand.
'And if you find the right spots to stimulate, we know that also the correct
areas of the brain cortex will be activated. In other words, if you put pressure
on the index finger of the artificial hand, the index finger area of your brain
will be activated.'
Professor Fredrik Sebelius of the Department of Electrical Measurements at
Lund University said, 'The neural interface of the future could be implanted
inside the arm which could then be connected to the peripheral interface.'
Professor Sebelius, who is also co-coordinator of SMARTHAND, added: 'The internal
interface could then receive and measure signals coming directly from the brain,
and at the same time send sensory signals to the brain. It would transmit the
signals as radio waves to the external prosthesis which would then be controlled
and register sensation.'
SMARTHAND partners are ARTS Lab, Scuola Superiore Sant'Anna (Italy), Aalborg
University (Denmark), Tel Aviv University (Israel), Tyndall Institute (Ireland),
Ossur (Iceland) and SciTech Link HB (Sweden).
Source: Cordis
Posted October 9th, 2009
|
