While most high schoolers were stuck indoors binge-watching shows during the COVID-19 pandemic, Benjamin Choi, a 17-year-old from Virginia, was quietly engineering what could become a revolution in affordable prosthetics.
Armed with little more than a $75 3D printer, scrap parts, and a deep curiosity, Choi created a mind-controlled robotic arm that costs just $300 to build. Even more astonishing? It doesn’t require any invasive brain surgery.
His invention combines artificial intelligence, brainwave interpretation, and 3D printing—all from a home basement setup—and it could change lives around the world.
The Origin: Inspiration from a Childhood Documentary
Benjamin’s story begins long before the pandemic. In third grade, he watched a “60 Minutes” documentary featuring mind-controlled prosthetics. These high-tech limbs, often used by military veterans and research subjects, moved using signals directly from the brain.
But there was a catch.
- The systems shown in the documentary cost hundreds of thousands of dollars.
- They also required invasive brain implants—surgical procedures not available or safe for most people.
That stuck with Choi. As he got older, he kept asking one question:
“What if there was a non-invasive, affordable alternative?”
Pandemic Disruption Turned Opportunity
In 2020, Benjamin’s summer research internship was canceled due to COVID-19. Instead of wasting time, he turned his focus inward—literally, toward the brain.
He set up a small lab in his basement, repurposed his sister’s $75 3D printer, and got to work on a dream project: a robotic arm that anyone could build and control—with their mind.
How It Works: The Science Behind the Arm
Choi’s robotic arm bypasses expensive implants or complex surgery. Instead, it uses a non-invasive EEG-based brain-computer interface (BCI).
Here’s the breakdown:
- Two small electrodes are placed on the user’s forehead and earlobe.
- These electrodes detect brainwave activity, focusing on electrical signals tied to motor intent or focused concentration.
- An onboard AI algorithm processes the EEG data in real time.
- The AI translates the brain signals into commands that move the robotic arm—open, close, rotate, etc.
- The arm itself is 3D printed using lightweight and durable materials like PLA and ABS plastic.
“I wanted to make something that was easy to use, accessible to all, and didn’t require anything invasive,” Choi explained in an interview.
75 Iterations to Perfection
This wasn’t a one-and-done project. Benjamin’s arm went through over 75 design iterations—each with improvements in structure, motion range, or signal accuracy.
He faced early challenges like:
- Noisy brainwave data, which made signal decoding tricky.
- Inconsistent hand movement due to latency between brain signal and mechanical motion.
- Hardware failures in servos and joints due to 3D print tolerances.
But he stuck with it. With each version, the arm became more responsive, more precise, and more functional.
Recognition and Impact
Choi’s work didn’t go unnoticed. In 2022, he was selected as one of the top 40 finalists in the prestigious Regeneron Science Talent Search, often dubbed the “Junior Nobel Prize.”
His project earned widespread praise for:
- Originality
- Social impact potential
- Technical sophistication at a young age
The fact that he did all of this without access to a full lab, grant funding, or university resources made it even more impressive.
How Is This Different from Traditional Prosthetics?
Let’s compare Benjamin’s invention to current high-end prosthetic options.
| Feature | Traditional Mind-Controlled Arm | Benjamin’s Robotic Arm |
|---|---|---|
| Cost | $100,000–$500,000 | ~$300 |
| Requires Surgery? | Yes (brain implants) | No |
| Manufacturing | Custom industrial fabrication | 3D printed at home |
| Brain Interface | Invasive neural implant | Non-invasive EEG |
| Accessibility | Very limited | Potentially global |
This isn’t just a cool gadget. It’s a democratization of prosthetic technology.
Potential Applications Beyond Prosthetics
While the obvious use case is prosthetics, Benjamin sees wider applications, including:
- Wheelchair control for people with ALS or paralysis
- Smart home automation via thought commands
- Hands-free digital interaction in AR/VR environments
- Use in developing nations, where cost limits access to advanced assistive devices
The idea of using brainwave commands for device control isn’t new—but Benjamin’s method makes it cheap, portable, and non-invasive, which is a huge leap forward.
The Role of AI in the System
At the heart of Benjamin’s invention is a machine learning model that can:
- Filter out noise from raw EEG signals
- Recognize user intention based on specific brainwave patterns
- Adapt and learn over time to improve accuracy with each use
This makes the system personalizable and scalable. The more the user interacts with it, the more accurate it becomes.
AI also allows the system to:
- Operate on lower-cost processors
- Avoid bulky data centers or expensive cloud connections
- Run fully offline, which is crucial for real-world deployment in remote areas
Next Steps and Future Vision
Benjamin is far from done. He has:
- Filed for provisional patents for his system
- Plans to open-source parts of the design for educational and humanitarian use
- Hopes to partner with medical institutions and nonprofits to bring the arm to real users
- Envisions a future where his tech enhances lives globally—not just in labs or hospitals, but in homes and villages everywhere
“I want this to be more than a science fair project,” Benjamin said.
“I want it to be a tool that helps real people regain control of their lives.”
What This Means for the Future of Assistive Tech
Benjamin’s story proves that young minds with limited tools can solve billion-dollar problems—problems big corporations often overlook because the profit margins aren’t there.
This kind of grassroots innovation can:
- Reduce dependency on high-cost medical systems
- Empower individuals in underserved regions
- Spark a wave of DIY biotech solutions
More importantly, it shows that the next era of human-computer interaction may not come from Silicon Valley—but from a basement workshop run by a teenager with a printer and a purpose.
Conclusion
What Benjamin Choi has built is more than just a robotic limb. It’s a statement.
- That technology can be accessible.
- That brains and passion are more powerful than money.
- And that the future of healthcare, mobility, and autonomy might just begin in the minds of our youth.
This mind-controlled arm proves that the next frontier of assistive tech is not only about how advanced we can make it—but also how affordable and inclusive we dare to dream.
