Bringing the sense of touch to prosthetics with Neosensory

The winners are in for Neosensory’s second developer contest. Our judges were thrilled with the dozens of inventive entries that leveraged Buzz to create devices ranging from health monitors to echolocation devices. In this ongoing series, we’ll be showcasing the most exciting submissions. To see all winners, click here.

A group of software engineers took the motto of Neosensory’s second contest, Expand your Senses, to heart: Kirill Shatilov, Kirill Konovalov, and Alex Wong built BuzzNPoses, an affordable way to “feel” artificial limbs.

The team was inspired by the many different applications of artificials limbs, ranging from robotic hands for the handling of toxic chemicals to the full replacement of lost limbs.

While advanced prosthetics allowing the wearer to gain a sense of touch do exist, many cheaper prosthetics do not feature such technology. That’s why Shatilov, Konovalov, and Wong decided to explore a more affordable option that allows amputees to experience sensory feedback. This can also significantly improve the prosthetic’s usability

The group used Buzz for this purpose, a wristband with four vibrating motors capable of creating millions of distinct vibrational patterns in order to send information to the wearer.

“The range of available patterns of the Buzz gives us an opportunity to encode both the state of the hand with all its five fingers and the dynamic response from our movements in a compressed signal over the four motors of the Buzz,” they write.

Building the BuzzNPoses

The project consisted of four parts: 

  • A moveable hand prosthetic, produced in a 3D printer 
  • Hardware consisting of five motors and a chip to receive commands and control the hand 
  • A Myo gesture control armband that reads the electrical activity of muscles and motion of the arm 
  • A Buzz band that translates sensation back to the wearer
  • And an app to facilitate communication between the parts.

In short, the Myo band picks up muscle activity and gesture intentions, which controls the prosthetic hand, and Buzz receives the information and communicates it to the wearer via vibrations. This information includes touch as well as the position of the five fingers.

“By stringing together our prosthetic hand and the Buzz, we created a simple device providing a complete cycle of interaction with the world, from acting to receiving feedback,” the team says.

The app orchestrates all the data streams within the network, “like a spider in the middle of the web,” the team says. A training game helps the wearer recognize what vibrations correspond to what gestures. The team called the app “Buzzinder” because the user swipes left or right on an image of a gesture– much like users of the app Tinder swipe left and right.

The project was not without obstacles. The team had little experience in soldering, which made the hardware construction difficult, and not all sensors survived the soldering iron. In the end, the three made it work and created a functioning, moving prosthetic.

What’s next

Even though the group managed to build a working prototype, they foresee more work that needs to be done.

“The chassis of our hand only permits five bendable fingers, which allow only simple gestures and grasping,” the three write. “This is far from the range of motion accessible to a real human hand. To approach the natural range of motion, more actuated joints need to be added. This is a serious engineering problem that should seek to balance technical sophistication with the low cost of production and ease of maintenance.”

The group would also like to recruit a cohort of real users for further testing and refining.

To learn more about the project, read the group’s contest entry here.