We've seen a number of drones that have been enclosed in a spherical frame for extra safety and durability, but that surrounding cage makes the drones much bulkier and not really suitable for carrying packages. Using an origami-like carbon-fiber cage, researchers at EPFL's Laboratory of Intelligent Systems have developed a spherical drone that can be folded up up to be more compact when not in the air, and unfolds to protect packages of up to 500 g (17.6 oz) while making deliveries.

The ability of unmanned aerial vehicles to carry parcels from point to point has numerous advantages. By being able to fly over obstacles, drones can reach their destination regardless of terrain, the state of the roads, debris, or traffic. This means that, in emergencies or when dealing with high-value items, drone-borne packages can be worth sending, even if they're small and lightweight, if it means getting medicines or other vital payloads to where they need to be.

The problem is that in order to carry larger packages, the drones have to be larger, which is not only a problem in the air, but on the ground when it comes to storing the drones. In addition, this means larger blades that could be dangerous to be near during takeoffs and landings.

The EPFL drone folds, reducing the volume by 92 percent EPFL

The new EPFL drone gets around all of these problems by containing both the package, which is suspended in the center of the apparatus, and propellers inside a folding composite cage. This protects the payload in the event of a collision or fall, and it means that the recipient can catch the drone or simply pluck it out of the air when it reaches its destination – an advantage if, for example, the delivery needs to be made to the window of a building.

When the drone is opened, the cage folds flat in a single movement, reducing the craft's volume by 92 percent and making it small enough to stow in a backpack. The drone is controlled through a smartphone app and can follow a flight plan to avoid obstacles, as well as returning autonomously to base after it's completed its mission.

The EPFL drone and it's protective cage EPFL

The drone has a number of safety features that include protection against hacking and a future version will include a parachute.

"This project is a work in progress – in addition to strengthening its ability to detect and avoid objects, we are exploring possibilities to increase the drone's payload capacity and enhance its autonomy," says drone developer Przemyslaw Kornatowski. "Throughout the summer, we tested our human-friendly, drone-delivery system on the EPFL campus, delivering items to people over 150 test flights

The results of the EPFL drone project will be delivered at the IEEE/RSJ International Conference on Intelligent Robots and Systems, Vancouver, Canada.

The video below introduces the foldable drone.

Source: EPFL