Aerodynamic design of transport drones

eVTOL glider, aerodynamics, structural design, complex battery systems

© Fraunhofer IOSB
Design ALBACOPTER® 0.5

ALBACOPTER® is a lighthouse project of the Fraunhofer-Gesellschaft. It was launched in 2021 and has a project duration of four years. The participating institutes are IVI, IOSB, IEM, ICT, IMS and LBF.

»ALBACOPTER®«: Experimental Vertical Take-Off and Landing Glider

Developing the third dimension of urban traffic space, in terms of Urban Air Mobility (UAM), opens up solutions for increasing logistical flexibility, while overcoming the negative consequences of a constantly-increasing volume of traffic. As part of the Fraunhofer »ALBACOPTER®« lighthouse project, six institutes are developing an innovative drone concept capable of making a significant contribution to electrified autonomous, pollution-free (peri-)urban air traffic.

The development of drones is booming. They are used in a variety of ways: in leisure applications, for example, drones are used to perform aerobatics, drone racing or filming; in professional applications, they are used as a surveillance tool or to transport important goods. Drone manufacturers are enjoying an increase in demand. In the ALBACOPTER® lighthouse project, a Fraunhofer team is researching drones of an extended payload class. The focus is on the development of eVTOL gliders, the first variant of which will have a take-off mass of 125 kg.

Schematic representation of component integration into the fuselage structure

Aerodynamic and structural mechanical design and construction

In the ALBACOPTER® team, Fraunhofer LBF is responsible for the aerodynamic and structural mechanical design and construction of the wings and fuselage. The fuselage is designed using the frame construction method from pultruded profiles and nodal elements with the requirement to safely integrate all necessary components such as the wings, battery, transport box, sensor systems and electronics (see Fig. 2). In addition, the Darmstadt team is developing the electrical energy storage system, including its own battery management system. The challenge is to meet the very high energy requirements for the vertical flight phase without the system overheating. Furthermore, the cell structure must be designed with as little mass as possible. The total mass of the so-called ALBACOPTER® 0.5, including the payload, is limited to 125 kg.

The key aim of this project is to first use the ALBACOPTER® concept to develop innovative technological approaches in relation to electronic transport drones that bring together the advantages of agile multicopters and the efficiency of gliders, as well as allowing for great versatility. Part of this project will be an experimental platform capable of flight, which will be used to investigate modular and scalable system solutions, depending on what the transport mission is. In this context, the necessary range, the payload being transported and the speed of flight will play a decisive role. As part of the project, real, airworthy eVTOL gliders are being built to serve as technology carriers, which will be used for test and demonstration flights within the project.

© Fraunhofer IVI
Vision eines Albacopters
© Fraunhofer IVI
Albacopter mit integrierten Batteriemodulen

As a lightweight construction institute, Fraunhofer LBF will work on the aerodynamic design of all structural components of the drone’s body and wings as part of this project. In this regard, emphasis is being placed on the use of sustainable, bio-based, recyclable materials, the integration of electromechanical interfaces in the wings and the integration of sensors to monitor the load-bearing lightweight structures. This also includes the development of transport boxes with additional functions. Within the project, LBF is also focusing on the development of ALBACOPTER® battery systems with their own battery management and monitoring system, along with reliable integration of the energy storage unit into the lightweight structure, as shown left).

Areas of application for eVTOL gliders include, inter alia, just-in-time logistics networks and automatic supply systems for urban and rural settings, with maximum distances of 200 km and a maximum payload of 200 kg.

In the Fraunhofer ALBACOPTER® lighthouse project, this flying experimental platform with the VTOL capability of a multicopter and the aerodynamic advantages of a glider is to be developed and approved for test flights by the end of 2024. Six institutes of the company (ICT, IEM, IOSB, IMS, IVI and LBF) are bringing their expertise and technologies to this ambitious research project. Find out more here: www.albacopter.fraunhofer.de

© Fraunhofer IVI