That ring flying in circles around the room looks like it has a life of its own. It's going at 1.4 meters per second, and engineered from a quadrotor (also known as a quadcopter or quadrotor helicopter), a helicopter propelled by four rotors.In this video by Rajan Gill from the Institute for Dynamic Systems and Control, ETH Zurich, he explains that while quadrotors are agile and have high load carrying capabilities, they're not very efficient in forward flight. Their lift to drag ratios are comparable to that of a fruit fly, he says. The flying ring, on the other hand, can fly on its side, allowing the blades to propel it forward faster than a typical quadcopter.The flying ring in the video is the first prototype of the augmented quadrotor with an angular wing, acting as a lifting surface which also conceals propeller blades for safety. The prototype's autonomous controlled flights, as seen in the video, allowed researchers to identify its aerodynamic properties.The ring flies inside a "flying machine arena," described as a "sandbox environment" for testing mobile robots. The size of the room allows the machines enough space for fast-paced experimental motion, in the air or on the ground. "The Flying Machine Arena offers ideal conditions to test novel concepts thanks to a high-precision localization system, high-performance radio links, easy-to-use software structure, and safety nets enclosing the space," its website describes. The space is used in various projects by various research labs, including the Institute for Dynamic Systems and Control.With more efficient forward flight, speed and carrying capacity, the quadrotor, as shown in the video, can be used for various lifting and transportation tasks to assist humans.