First bionic fingertip

Can differentiate rough, smooth textures w/ 77% accuracy

DENNIS Aabo Sørensen from Denmark is the world’s first amputee to feel textures in real-time with the help of bionic fingertip connected to his nerves in the upper arm.

He lost his hand in a firework accident a decade ago, now, he is able to detect shape and consistency of objects with the device, as well as the strength of his grasps.

Using a novel bionic fingertip, he was able to accurately distinguish the texture by 96 percent.

The creators of the artificial fingertip including Silvestro Micera of the Ecole polytechnique fédérale de Lausanne (EPFL) in Switzerland, says that this development is one step closer to “sensory restoration in the next generation of neuro-prosthetic hands.”

The artificial fingertip is controlled by a machine to move the device across a selection of texture plastics: smooth and rough. Generated by an electrical signal as the device moves across the plastic, it is then converted into a number of electrical spikes that mimicked nervous system signaling, simulating touch.

In a similar study published in the journal eLife, Micera, along with his colleagues tested the efficacy of the bionic fingertip for identifying textures using four non-amputees.

The researchers used fine needle microsimulation to temporarily attach the bionic finger to the participants. By comparing each non-amputee’s brainwaves as they use the bionic finger and their own to touch the textured surface, it revealed that touch sensations produced by the bionic finger were similar produced by a real finger.

They were then able to differentiate rough and smooth textures with almost 77 percent accuracy.

“The promising results obtained with microsimulation in four intact subjects, combined with robust translational indications from the hybrid model and an excellent outcome from one amputee, prompt the idea that neuromorphic stimulation could be a natural and effective tool for eliciting texture discrimination abilities via hand prostheses,” the researchers said they have high hopes that artificial fingertip can be developed and safely tested among non-amputees without the costly need for surgery. Ma. Vanessa L. Estinozo with a Medical News Today report

Vital Signs Issue 87 Vol. 4, May 1-31 2016