We've kept a pretty stern eye on the development of GRASP Lab's quadrocopters, and with good reason it seems, now that the four-bladed aerial ninjas have even more alarming abilities at their disposal. In the video after the break, watch them hold a variety of complex formations like it's no thing -- even while on the move. The 'copters can also take flight, or resume position, after being thrown into the air, navigating real world obstacles with deft fluidity. It's part of University of Pennsylvania's Scalable sWarms of Autonomous Robots and Mobile Sensors project (conveniently SWARMS for short), which is responsible for developing the air-born acrobats' new grouping skills. They say it's an attempt to replicate swarming habits in nature, though we're not convinced.