Electromyography, or EMG, is a type of sensing technology used to evaluate the health of muscles and the motor neurons that control them. When you want to move a muscle, an electrical signal is sent from your brain through the motor neurons in the muscle. This voltage can be measured through a sensor on your skin. Scientists have found ways to use this signal to control mechanical devices such as exoskeletons or prosthetic limbs.

For their senior design project, USC Viterbi mechanical engineering students Shana Douglass, Hilina Gudeta, Emily McTiernan and Brandon Tieu explored this technology for themselves. Using low-cost electronics, they built and programmed an EMG-powered motion controller for less than $200. Their goal: to one day turn their prototype into an assistive exoskeleton. To demonstrate their device’s ability, the group constructed a robotic arm that mimics their movements through a bicep curl.