The prosthetics room is experiencing a major change, but the change isn’t from a big lab or a company that is worth billions. It’s a result of a high school basement project in Virginia. Benjamin Choi, 17, has come up with a brain-controlled prosthetic arm that is affordable, safe, and smart.
Choi’s exploration did not happen as he wished; actually, his first plan to study aluminum fuels in a laboratory was canceled due to the pandemic. He didn’t put away his dreams; instead, he turned his family’s ping-pong table into a workshop. When he was a kid, Choi saw a documentary about brain-controlled artificial limbs—an extremely risky operation and costly technology. That stayed with him. After that, he set himself a challenge: could he come up with a brain-controlled prosthetic arm without the need for surgery, and that was affordable?
It turns out the answer is yes. With a $75 3D printer and common materials such as fishing line and rubber bands, Choi created a prototype that reads brain signals through electroencephalography (EEG). Rather than having anything implanted into the brain, the system involves two tiny external electrodes-one taped to the earlobe to provide a baseline measurement, and the other on the forehead to capture brainwave information. That is transmitted wirelessly through Bluetooth to a microchip within the arm, where an artificial intelligence model interprets the user’s intentions into motion.
The degree of innovation here is astonishing. Choi wrote over 23,000 lines of code and created seven new sub-algorithms to get it to function, shrinking the entire AI model so that it would fit onto the chip within the arm. He trained the system using brainwave readings from six adult volunteers, having them concentrate on particular hand movements. The AI became better with time, learning to identify individuals’ unique neural patterns and adjust accordingly, becoming more precise the more it was utilized.
The results speak for themselves. Choi’s prosthetic achieves a mean accuracy of 95 percent—well above the previous best of 73.8 percent for similar non-invasive devices. The arm is strong, built from engineering-grade materials, and can handle loads of up to four tons. Even more impressive, it costs less than $300 to make—compared to the tens or hundreds of thousands for most commercial prosthetics.
He hasn’t been overlooked. Choi was put forward as a top 40 finalist in the Regeneron Science Talent Search and also received several awards at the Microsoft Imagine Cup and Regeneron International Science and Engineering Fair. Nevertheless, what inspires him the most is the effect on ordinary people. Joseph Dunn, a person who has undergone an upper-limb amputation, got in touch with Choi after figuring out his project and gave him some feedback to make the arm more functional. This has been the case with MIT and Stony Brook University, and the closeness to clinical trials for this particular design as a result of these collaborations.
Choi’s aspirations are not limited to prosthetic arms. His point of view was that the AI brainwave technology developed by him can be a method to control the wheelchair, and can be a medium through which people with ALS may communicate, apart from being the source of power for a range of assistive devices. In fact, with two provisional patents already in the works, he is setting the stage for a future in which these gadgets are available everywhere.
One factor that not only differentiates Choi’s story from other success stories, but also his engineering skills and mindset, is his representation of the most advanced technology that is not necessarily required to be expensive or out of reach for the common user. The most difficult thing in the engineering world can be turned into something new by combining creativity, empathy, and the denial of the idea that ‘this is the only way to do it.
At the moment, the future of prosthetics is being revolutionized in a very unexpected place – a teenager’s basement workshop. And quite often, the only things that are needed to make technology available to everyone are a ping-pong table, a 3D printer, and pure willpower.
