The device also could have valuable agricultural uses, "flying down in the plant canopy, looking for disease and measuring parameters like humidity, with much finer detail than is possible with overhead drones, enabling a new sort of'micro agriculture,' that could locally tailor the environment to optimize yields," Fuller says. Thus, he says releasing the bug from its leash "was really a necessary step to enable them to fly freely and perform the applications we envision." Perching -- staying aloft in the air with buzzing or flapping, landing and staying there -- is another goal. "Perching is something we're interested in because that's a very efficient way to operate for a long time, and it has already been demonstrated on the RoboBee, which still had a wire at that point," says Johannes James, a mechanical engineering doctoral student and member of the team. Robotic flies could alight on supports along a pipeline, or in a refining facility, for example, and perform long-term sensing along the length of the pipes, and then move elsewhere to collect more data, according to James.