Scientists in Newcastle have developed a cheap way of helping amputees with prosthetic limbs reach out and grasp objects - a bionic "hand that sees". The hand was developed by bioengineers at Newcastle University who modified a standard NHS myoelectric hand with a cheap camera to provide upper-limb amputees with a more functional prosthetic.
Myoelectric hands allow amputees to make their prosthetics express different grips using sensors on the skin surface of the stump which detect the electrical activity of wearers' muscles. With the added camera, which the researchers say they purchased for 99p, the new device bypasses the usual processes of gripping with a myoelectric hand, which require the user to see the object, physically stimulate the muscles in their arm and trigger a movement in the prosthetic limb. The wearer points the camera at the object they want to grasp, tenses their arm muscles and the prosthetic controller automatically recognizes the shape and adopts the correct grip to pick it up.
To achieve this the Newcastle team had to teach the prosthetic controller how to recognize different shapes and select which grip to use.
"We would show the computer a picture of, for example, a stick," explained Ghazal Ghazaei, the lead author behind the research, which was published today in the Journal of Neural Engineering. "But not just one picture, many images of the same stick from different angles and orientations, even in different light and against different backgrounds and eventually the computer learns what grasp it needs to pick that stick up.
"So the computer isn't just matching an image, it's learning to recognise objects and group them according to the grasp type the hand has to perform to successfully pick it up.
"It is this which enables it to accurately assess and pick up an object which it has never seen before - a huge step forward in the development of bionic limbs." Dr Kianoush Nazarpour, the paper's co-author and a senior lecturer in biomedical engineering at Newcastle University, said: "Using computer vision, we have developed a bionic hand which can respond automatically. "Just like a real hand, the user can reach out and pick up a cup or a biscuit with nothing more than a quick glance in the right direction.
"Responsiveness has been one of the main barriers to artificial limbs. For many amputees the reference point is their healthy arm or leg so prosthetics seem slow and cumbersome in comparison. "Now, for the first time in a century, we have developed an 'intuitive' hand that can react without thinking." A small number of amputees have already trialled the new technology, including Doug McIntosh, who lost his right arm in 1997 through a rare form of cancer called epithelial sarcoma. "The problem is there's nothing yet that really comes close to feeling like the real thing," explained the father-of-three who lives in Westhill, Aberdeen, with his wife of 32 years, Diane. But the new responsive hand being developed in Newcastle is a "huge leap forward," he said.
http://news.sky.com/story/researchers-develop-seeing-bionic-hand-with-99p-camera-10861889
