Self-taught Engineer Builds Brain-Controlled Prosthesis

Self-taught Kenyan engineer David Gathu has turned his ingenuity and interest in electronics into innovations that help the disabled. Here he's wearing the brain-controlled prosthetic arm he and his autodidact cousin Moses Kiuna cobbled together from salvaged parts. The headset picks up brain signals and converts them to electric current that is directed to a transmitter. The transmitter wirelessly relays the signals in the form of commands to the arm, which responds with movements that match the wearer's intentions.

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