17-Year-Old Builds a Mind-Controlled Robotic Arm Using AI and 3D Printing — For Just $300 A 17-year-old student innovator has built a mind-controlled robotic arm using AI, brain–computer interface (BCI) signals, and 3D printing, at a cost of around $300—a fraction of traditional prosthetic systems that can cost tens of thousands. The arm uses EEG sensors to read electrical signals from the brain. An AI model interprets these signals into movement commands, which are executed by a 3D-printed mech