You've heard of robotic bees, but have you heard of robotic butterflies? Chinese researchers have published a study that focuses on their efforts to develop solar-powered wings that imitate the flapping motion of a butterfly. They were able to develop wings that can do this at a rapid rate using light-driven actuators, and a new video shows all of the different ways they can utilize what they've created. The study was published in the journal ACS Applied Materials & Interfaces on January 16th, and a video put out on Wednesday explains how the project came together. When the wing was exposed to the heat of a strong light source, much like the Sun, the polymer layer on the bottom expanded significantly more than the metallic layer on the top, which caused the wing curl.