UPenn's GRASP Lab has done some absolutely spectacular things with quadrotors. They've taught them to fly in formation, build structures, and even fling themselves through narrow windows. But as with every learning process, there are going to be some cases where things just don't go quite right, and when you're dealing with fast moving autonomous robots with four spinning rotors apiece, sometimes tests can be, to quote UPenn, "spectacularly unsuccessful":
Spectacular is right. I'm not sure what exactly caused the attempted backstab at 0:20 or the mass suicide at 0:28, but all those violent quadrotor deaths were pretty funny to see. You know, for science.
Oh, and props to the GRASP Lab quadrotor team for sharing their failures along with their successes.
[ UPenn GRASP Lab ]