Amputee Feels Textures in Real-Time with Bionic Fingertip
Amputee Dennis Aabo Sørensen was able to feel smoothness and roughness in real-time with an artificial fingertip that was surgically connected to nerves in his upper arm. The nerves of non-amputees can also be stimulated to feel roughness, without the need of surgery, meaning that prosthetic touch for amputees can now be developed and safely tested on intact individuals. The technology to deliver this sophisticated tactile information was developed by researchers at Switzerland's EPFL and Italy's SSSA. The results provide new and accelerated avenues for developing bionic prostheses, enhanced with sensory feedback. Sørensen is the first person in the world to recognize texture using a bionic fingertip connected to electrodes that were surgically implanted above his stump. Nerves in Sørensen's arm were wired to an artificial fingertip equipped with sensors. A machine controlled the movement of the fingertip over different pieces of plastic engraved with different patterns, smooth or rough. As the fingertip moved across the textured plastic, the sensors generated an electrical signal. This signal was translated into a series of electrical spikes, imitating the language of the nervous system, then delivered to the nerves. Sørensen could distinguish between rough and smooth surfaces 96% of the time.