SynTouch’s Prosthetic Fingers Can Feel How Soft a Bunny Is

Wednesday, November 25th, 2015

If you’re holding a bunny, you can feel the fluffy fur and the warm body in your hands. You can also gauge how hard you’re holding it. But if you have a prosthetic arm or hand, you have to be super vigilant holding cute, furry creatures—since you can’t feel the amount of force you’re exerting, you run the risk of crushing them. Well, unless your prosthetic has an upgrade from SynTouch, a company that has built and perfected robotic fingers with the sense of touch.

Vikram Pandit, a prosthetics research engineer at SynTouch, was born without a hand and he says that the robotic fingers, called BioTac, will make his prosthetic easier and more intuitive to use. “It allows you to pay significantly less attention to manipulating fragile objects like an egg than with a non-sensorized prosthetic hand,” says Pandit.

His company’s robotic fingers take their shape and function from their human counterparts. They are about the half the length of an index finger, with one knuckle in the middle. Above the knuckle, the robotic fingertip has a blue rubber-like skin with ridges, which encases a fluid layer, a strip of electrodes, and a temperature sensor. On the back, a plastic rectangle acts as a fingernail, which is important for sensing force. (Try pressing your thumb and index finger together: You can see your skin change shape but your fingernails act as walls, measuring the force of what they’re pushing against.)

When the BioTac holds an egg, the movement of the fluid inside tells the sensors the location and magnitude of the fingers’ forces, and stops before it goes too far. And if you feel like stroking the egg, sensors can record vibrations from the ridges to be translated into texture information for the hand. In the video, Pandit makes an omelet with eggs, tomatoes, peppers, and mushrooms, a task he says would have taken much longer without sensitized fingers. “It’s basically going to allow me to move through my day quicker and faster and more like someone who has two hands,” says Pandit.


Start a Conversation