The article appears Online on July 11, 2016 and in print on July 12, 2016, on Page D6 of the New York edition with the headline: A ‘Living’ Robot: Artificial Stingray Powered by Light and Rat Cells. https://www.nytimes.com/2016/07/12/science/stingray-robot.html?_r=0
Scientists built an artificial stingray to respond to pulses of blue light. By blinking blue light, they were able to guide the robot to swim through an obstacle course with the undulating movements of an actual stingray. Credit Sung-Jin Park and Kyung Soo Park.