Funded by the Defense Advanced Research Projects Agency and spurred by the return of injured Iraq and Afghanistan war veterans, the research aims to design prostheses that will not only be able to move, but will also provide amputees and quadriplegics with a sense of touch.
Johns Hopkins gave Bensmaia’s lab about $1.5 million of its federal money to develop even more advanced prostheses that will eventually give the users a simulated sense of touch through the machine’s metal and motors.
But how do you replicate the feeling of a coffee cup in your hand or the difference between a five- and a 50-pound weight? The U. of C. scientists set out to identify and replicate the qualities of touch, including texture, shape and force, through complex mathematical equations known as algorithms.
Scientists implanted platinum alloy electrode arrays, each the size of a pencil eraser, into the monkeys’ brains. The scientists then created neural impulses by emitting small but focused electrical currents, and recorded the animal’s behavior in response.
After simulating thousands of touch sensations, Bensmaia and his team hope to build algorithms, essentially mapping out the way the brain reads those touches. They will then use those sensory algorithms to build software for the robotic arm’s computerized sensors that will transmit impulses to electrodes in the human brain, mimicking touch.