KU Leuven Researchers Use 3D Printing to Develop Hybrid CargoCopter Drones

The Katholieke Universiteit Leuven, or University of Leuven (KU Leuven), is located in Leuven, Belgium; if this sounds familiar, it’s because Materialise is also located in the city of Leuven, about 16 miles outside of Brussels. KU Leuven has been involved in some pretty interesting projects that required the use of 3D printing technology, such as a 3D printed, multi-color object called “The Brain of Vesalius” for a Materialise exhibit at the BELvue Museum, and it also 3D designed and printed silicon-carbide sprockets for a collaborative “not-bicycle” project.

A team of researchers at KU Leuven has been working to develop a new generation of hybrid drones, which they call CargoCopters, that are purported to double the range and speed of conventional multi-rotor drones. This type of drone has been the preferred choice for applications like inspection and filming where the drone needs to remain close to its pilot.

Multi-rotor drones are good at hovering in one spot, but thanks to their design, they typically only fly at low speeds and can’t remain airborne for long distances; these qualities are well-suited to applications like emergency services and deliveries. However, faster, more efficient fixed-wing drones are limited in terms of fully automated missions, as a person or catapult is needed for takeoff, and a necessary parachute, net, or runway for landing. The KU Leuven team has been working to improve both the range and the speed of multi-rotor drones, by combining the benefits of fixed-wing with those of multi-rotor drones to create a hybrid solution. The team’s hybrid drone is able to transition from hovering into an efficient cruise flight – the four propellers used for lift, thrust, and control are the only moving parts of the 3D printed KU Leuven drone, which makes it lightweight and low-maintenance, as well as strong.

The team was supported by the DIY Drones community for personal UAVs throughout the process. The first prototype they created, back in 2014, was called the VertiKUL. The VertiKUL design had a docking system, which allowed it to be fully automated, and featured a large wing that produced 100% of the required lift in cruise flight; additionally, it could transition from a hover to cruise flight of 90°. While the wing was helpful in generating the lift, it was very difficult to fly the VertiKUL in windy conditions, and to nail the automated landing.

For the second iteration of the VertiKUL, the team focused on improving the wind resistance of the 5 kg drone by reducing the large wing size, but compensating for the loss in lift by improving the aerodynamics of the drone. The partial transition was completed by the propellers, which operate at 45° with respect to flight direction, and produced part of the drone’s lift in cruise flight. After a few more tweaks, the team succeeded in creating its wind-tolerant, fast and efficient drone, which has been dubbed the CargoCopter.

The fully 3D printed CargoCopter drone is able to take off vertically using its four rotors, and then tilts 90° to fly straight. It was designed to cover distances up to 60 km and hit speeds up to 150 km per hour; it can also transport payloads up to 5 kg. It uses an RTK GPS for navigation, and deploys stereo cameras and sonars to ensure a safe landing. The team’s drone designs evolved pretty quickly, thanks to a parametric selection algorithm that optimizes each new CargoCopter design iteration “for its mission-specific requirements.”

The team told SUAS News, “The designs are specifically engineered to be suited for lightweight 3D printing. Thanks to this agile methodology, we were able to design, manufacture and test-fly dozens of prototypes with gradual improvements leading up to doubling speed and range compared to standard multi-rotor drones.”

3D printed drones are certainly not new: we’ve seen the technology used to make heat-resistant drones that contain embedded electronics, search and rescue drones, underwater drones that can shoot up into the air, and even drones that will deliver a Slurpee to your door. I’m sure the potential applications for a drone like the CargoCopter, which combines the benefits of both fixed-wing and multi-rotor drones, will be numerous. Discuss in the 3D Printed Drones forum at 3DPB.com.

[Source: SUAS News]