“Conventional prosthetic arms are little more than sophisticated hooks that offer very little freedom of movement. They offer just three degrees of freedom: opening and closing the hand, rotating the hand inwards and outwards, and bending and extending the elbow. And going through those motions requires concentration and a level of skill that can be rather exhausting. Advanced prosthetic arms promise a lot more. While not a perfect replacement for a human limb, the idea is to offer almost the same level of flexibility, dexterity and feedback that the hand can. An extraordinary project from the Defense Advanced Research Projects Agency promises to make it happen. Darpa’s $100 million Revolutionizing Prosthetics 2009 Program aims to create a thought-controlled functional arm within this decade. The project is a collaborative effort with more than 30 organizations including labs, universities and private companies.”