Ultrasound imaging turns a robot hand into a skillful mimic

Our hands are the nimblest parts of our bodies, coordinating 34 muscles, 27 joints, and over 100 tendons and ligaments to perform countless nuanced movements and gestures. So far, robots have been notoriously bad at mimicking that dexterity, in part because researchers struggle to capture what is actually going on under our skin in order to reproduce it. Now MIT researchers are pioneering a promising new approach.