When the COVID-19 pandemic struck for the first time, some of us were lucky enough to have enough free time to develop skills or work on a passionate project. For some, this meant learning how to bake bread; for 17-year-old Benjamin Choi, this meant developing a prosthesis for the arm that could be controlled by the user’s mind.
Choi has always been fascinated by the thought-controlled concept of prosthetics, seeing it for the first time in an episode of 60 Minutes, according to Smithsonian magazine. But he didn’t like how inaccessible these prostheses were, as they required brain implants (and therefore risky surgery) to work. So when the pandemic hit the brakes on Choi’s summer research project, he set out to come up with a cheaper and safer solution.
He uses previous engineering and coding experience (gained from school and Stack Overflow) to design a durable prosthetic arm, as well as an AI algorithm capable of translating the user’s brainwaves into commands. The system is accompanied by a relatively small headset that uses electroencephalography (EEG) to read the user’s brain waves. The headset sends this reading via Bluetooth to a microchip embedded in the prosthesis, where Choi’s algorithm deciphers the brain waves and turns them into motion. Making the final product costs only $ 300.
As easy as this kind of Choi was, his journey to developing a working prototype was not easy. Initially, he wanted to store his algorithm in the cloud and communicate over Wi-Fi. However, this was not practical, as the user will have to stay connected to Wi-Fi and the movements of the prosthesis will be significantly slowed down. He also created more than 75 versions of the prosthesis before focusing on its final design.
Today, Choi’s algorithm consists of “over 23,000 lines of code, with 978 pages of math and seven completely new subalgorithms.” Its average level of accuracy is 95 percent, which far exceeds the industry standard, which Choi says is around 73 percent.
Since his invention attracted widespread attention last year, the high school graduate has won numerous awards. He also won a scholarship to Stony Brook University and received a scholarship to manufacture his prosthesis. Choi even received temporary patents for both the prosthesis and his algorithm, although it has been published instructions for anyone who wants to print their own 3D prosthesis on the arm.