A small, autonomous helicopter can direct lighting just where a photographer needs it. Researchers at MIT and Cornell University developed the drone system to respond to the movements of a photographer and her subject using lidar and input from the photographer’s camera. They tested their concept by having the drone perform “rim lighting,” a difficult-to-produce effect where the subject is brightly lit only at the edges. “It’s very sensitive to the position of the light,” said Manohar Srikanth, a former MIT postdoctoral researcher who now works for Nokia. “If you move the light, say, by a foot, your appearance changes dramatically.” MIT researchers equipped a robot helicopter with a continuous light source, a photographic flash, and a laser rangefinder. Courtesy of MIT. With the new system, the photographer indicates the direction from which the rim light should come and the desired width of the rim, and the drone positions itself accordingly relative to the subject. The drone automatically maintains the specified rim width. Roughly 20 times a second, the camera sends an image to a computer controlling the drone. An algorithm evaluates the rim width and adjusts the drone’s position accordingly. “The challenge was the manipulation of the very difficult dynamics of the UAV [unmanned aerial vehicle] and the feedback from the lighting estimation,” said MIT professor of computer science and engineering Dr. Frédo Durand. “That’s where we put a lot of our efforts, to make sure that the control of the drone could work at the very high speed that’s needed just to keep the thing flying and deal with the information from the lidar and the rim-lighting estimation.” The researchers will present their system at the International Symposium on Computational Aesthetics in Graphics, Visualization and Imaging next month in Annecy, France. For more information, visit www.mit.edu.