Student designs brain-controlled prosthetic hand

MECHANICAL HAND: Waikato University masters student Mahonri Owen with his mechanical hand.
MECHANICAL HAND: Waikato University masters student Mahonri Owen with his mechanical hand.

Future victims of accidents or warfare may have Waikato University student Mahonri Owen at least partly to thank when it comes regaining the ability to throw a ball or hold a coffee cup. 

Owen, 25, is in his fifth year of study in mechanical engineering and is in the throes of designing a brain-controlled electro-mechanical prosthetic hand as the subject of his master's thesis. 

The motivation for attempting to re-create an artificial example of one of the most complex and important parts of the human anatomy came from several sources. 

Owen grew up in a Mormon family in Dinsdale where his mum was always cooking for other people and giving a lot of service in the community. 

''So I had the feeling I wanted to do something that could help people out. It really hit a note when one of my wife's cousins had a little boy that was born with a webbed hand.'' 

The idea was cemented by a suggestion from his Waikato academic supervisor Dr Chi Kit Au. 

''He suggested the idea and I jumped on it.'' 

The project began in April. First came an online study of what was going on in the development of prosthetic limbs around the world.

Building a brain-controlled hand is not an easy thing to do. 

''I only have a year. The aim is to build a hand and programme it to do the simple things like a power grip, key grip, ball grip and pinch.'' 

Owen has already built the 'skeleton' of the hand. Using on-screen CAD (computer aided design) to map-out the mechanism the components were created using a 3-D printer which lays the design down in resin 0.3 of a millimetre at a time.

As one layer hardens, another is added until the entire design is built up. 

The mechanism has about 50 components and took seven hours to print, but by using the 3-D printer, at  fraction of the cost - $240 - of using traditional methods of fabricating a prototype. 

The parts were assembled by hand and Owen was last week working to fit the electronic actuators.  When completed the aim is to have an electro-mechanical hand which could be surgically connected to the nerve endings in the patients arm which could allow it to be controlled directly from the brain. 

Next year Owen would like to take his studies on to the Phd level, but is also aware he has a wife and child and needs to earn a living.

Waikato Times