Micro-drones with winches can open doors and lift 40 times their own weight

Micro-drones are nifty little things: small, fast, and agile. But they’re not the strongest machines around, and are barely capable of exerting more force than a small mouse head-butting your ankle. Until now. Scientists from Stanford University and EPFL in Switzerland have created a micro-drone with a built-in winch that’s capable of lifting up to 40 times its own weight and performing simple mechanical tasks like opening a door.The key to the design is the use of interchangeable a