Dustin Tyler wants to give amputees feeling in their lost limbs. Along with his team at Case Western University Dustin is working with amputee Igor Spetic to develop a prosthetic that will restore hand sensation.
Sensors on the prosthetic hand record the pressure applied against the fingers. An external box transforms the pressure from the sensors into an algorithm. The algorithm is then directed to the nerve, sending signals to the brain. Igor's brain can interpret these signals as physical pressure acting on his hand.
http://www.technologyreview.com/sites/default/files/images/bionics.2x948.jpg
Several experiments are shown in this MIT Technology Review video. Pulling the stem off a cherry or pulling grapes from a stem are often repeated tasks. Spetic works with sensors on the prosthetic thumb and forefinger to coordinate with his existing hand.
Tests are done with the sensors on and off to demonstrate the value of the sensors and the benefit that the prosthetic is giving the user. A surprise benefit for me was the sense of purpose that these tests give to Spetic. He says in the video that he doesn't expect the research to give him a fully functional hand replacement but hopes that his part in this research will benefit others.
Tyler's work is incredible. A video on the Discovery Canada website shows the team working with the hand when not connected to Spetic's arm. Seeing a user feel sensation when the prosthesis isn't physically attached to his residual limb is amazing.
http://www.technologyreview.com/video/524861/restoring-a-sense-of-touch-in-amputees/