In the world of prosthetics, the development of a humanlike prosthetic hand has become a kind of Holy Grail-both profoundly desired and almost impossible to achieve. To truly mimic the human hand, after all, a prosthesis would need multiple ultra-precise grasps, extraordinarily variable speed and strength, thought-based controls, an interface that takes full advantage of the arm’s leverage and torque, a natural-seeming touch and appearance, and the ability to provide rich feedback to the wearer about its environment and the things it touched.
Government agencies, private corporations, and research institutes around the world are working on various aspects of the ideal hand, and The O&P EDGE has recently reported on a number of developments, including softer skin, better thought-based controls, and other innovations. Now, the European Union’s cooperative scientific consortium, the Sixth Framework Programme (FP6), has further developed a prototype hand that may provide better user feedback than any current model.
The SmartHand, a project that arose out of the combined work of researchers and engineers across Europe, has a variety of gripping functions, and more uniquely, contains 40 touch-activated sensors. According to European Research Headlines, the sensors stimulate the residual nerves such that the wearer feels the density of a touched object as if via an intact hand.
Professor Fredrik Sebelius of the Department of Electrical Measurements at Lund University is coordinator of the SmartHand project. He told Euronews that the hand may eventually be controlled by a neural implant that interfaces between the wearer’s nervous system and the hand’s electronics.
“The neural interface of the future could be implanted inside the arm which could then be connected to the peripheral interface,” he said. “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.”
The SmartHand’s first amputee test wearer, Robin af Ekenstam, told Euronews, “I am using muscles which I haven’t used for years. 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. 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.”
According to Euronews, before the device can be released to market, the research team will need to make a variety of changes to it, including minimizing the size of the device’s controls, actuators, and sensors. The team includes partners from institutions including ARTS Lab; Scuola Superiore Sant’Anna, Italy; Aalborg University, Denmark; Tel Aviv University, Israel; Tyndall Institute, Ireland; Össur, Reykjavik, Iceland; and SciTech Link HB, Sweden. According to Research Headlines, funding for the SmartHand equals approximately €1.8M ($2.68M).
To see the SmartHand in action, visit http://www.euronews.net/2009/09/22/the-magic-touch/
