Roboticists have two compelling reasons to turn to real animals for inspiration. As the brainiacs at Boston Dynamics study the musculature and motion of humans, cheetahs, and other animals, they're able to replicate the delicate, precise balance we take for granted every time we walk or run. And then there's the spy game: Using the form of existing animals to disguise robots as innocent creatures. Sometimes this shows up in the movies--who can forget a naked Jim Carrey squeezing his way out of a robotic rhinoceros in Ace Ventura?--but it actually seems more common in reality.
Case in point: Grad students at Virginia Tech won a five year grant from the US Office of Naval Research to work on underwater robots, and their current prototype, dubbed Cyro, is a 170-pound robo jellyfish. Cyro is an autonomous robot that mimics a real jellyfish's propulsion with a set of articulated metal limbs; it's designed to be tossed in the water and left to its own devices, its motion guided by a sensor package, for days or weeks or months on end.
The prototype isn't ready for that kind of long-term usage yet--it can only swim for about four hours on a rechargeable battery. But it's easy to imagine the robot improving over the next three years as the team continues to work with the Navy's grant money.
The jellyfish's "jelly" is a simple silicone covering lain on top of the robotic frame. While Virginia Tech's students are optimistic that Cyro could be used for oceanographic research, monitoring oil spills, and other academic causes, it's one of several robots being designed with military spy applications in mind. Drones are the least of our worries--check out the Air Force's Micro-Aviary plans for another example of nature feeding into robotics research.