We've covered the remarkable work that researchers at ETH Zurich have been doing with robots and quadcopters before, but did you know its facility has a dedicated Flying Machine Arena where they tether drones to poles and make them fly in circles at terrifying speeds? It's even more amazing than it sounds.
You'd expect a tethered drone to be a pretty boring spectacle, but without the risk of crashing into a wall, some of these quadcopters are able to hit speeds of up to 55km/h during these experiments. And four going at the same time look like they're able to suddenly spin up a tornado.
It's a good reminder of just how limited current artificial intelligence technologies are. When autonomously trying to avoid obstacles, drones often seem like they're slowly tip-toeing around a space so their rotors don't come into contact with anything. But when you get them out in the open, they can fly faster than most people realise. [ETH Zurich via IEEE Spectrum]