Reviewed by Lexie CornerApr 25 2025
An international team led by researchers from Empa and EPFL recently studied how aerial robots could process construction materials with precision in mid-air. This method shows potential for use in difficult-to-access locations or for tasks at significant heights.
Test wall at the DroneHub with modular components for experiments with flying construction robots. Image Credit: Empa
The flying robots are not intended to replace existing ground systems but to complement them in specific applications such as repairs or disaster relief.
Robotic arms and 3D printing gantries are already used on building sites, primarily as stationary systems on the ground. These systems often reach their limits in challenging terrain or at high altitudes. A team of researchers from Empa's Laboratory of Sustainability Robotics and EPFL explored the potential for using aerial robots as autonomous construction platforms.
In the cover story of the current issue of Science Robotics, the researchers outline the current capabilities and future potential of this technology. One advantage of construction drones is their ability to access locations that traditional machinery cannot, including mountains, rooftops, disaster sites, and even extraterrestrial environments.
These drones do not require a fixed construction site and can be deployed in swarms, offering flexibility and scalability. Additionally, they could help reduce transportation distances, minimize material use, and enhance safety at construction sites.
Repairs and Operations in Extreme Conditions
Aerial robots are particularly suited for disaster relief in areas affected by floods or destruction, where traditional vehicles cannot access. These robots have the potential to transport construction materials and assemble emergency shelters autonomously. They also show promise for performing repairs in hard-to-reach locations, such as detecting and repairing cracks in high-rise facades and bridges without the need for scaffolding.
Existing robotic systems on the ground often weigh several tons, take a long time to set up, and have a limited working radius. Construction drones, on the other hand, are light, mobile, and flexible—but so far, they only exist at low technology readiness levels. They have yet to be used for industrial purposes.
Yusuf Furkan Kaya, Study Lead Author, Sustainability Robotics Laboratory, Empa
Several academic prototypes already demonstrate various applications of airborne construction, including placing individual building elements, tensioning cable structures, and layer-by-layer printing of construction materials. For instance, at Empa, flying robots have been designed to work collaboratively to print materials layer by layer for construction or repair tasks.
Interplay of Technology, Material, and Design
Drones have significant potential due to their ability to operate and construct in various locations, provided there is access to energy and materials. Their scalability is also a key advantage: in the event of a disaster, hundreds of aerial robots could rapidly deploy temporary infrastructure in remote areas.
However, the use of drones in future construction will introduce new challenges. The researchers highlight that a key difficulty lies in the interdisciplinary nature of the technology. Aerial Additive Manufacturing (Aerial AM) requires simultaneous advancements in three fields: robotics, materials science, and architecture.
A drone may be able to fly precisely, but without lightweight, stable, and processable materials, it cannot develop its full potential. And even if both are available, building designs must be adapted to the limited precision of the aerial robots to enable load-bearing structures.
Mirko Kovac, Head, Laboratory of Sustainability Robotics, Empa
Complementing Existing Robots
In addition to cross-disciplinary collaboration, there are several technological challenges in robotics, including limited flight duration, payload capacity, and autonomy. The study proposes a five-stage autonomy framework, progressing from simple path-following flights to full independence, where aerial robots can assess the building environment, identify faults, and even adjust designs in real time.
Yusuf Furkan Kaya emphasized that this is not merely a theoretical model but a detailed development strategy.
“Our goal is to have aerial robots that understand what material they are building with and in what environment, and intelligently optimize the resulting structure during construction,” stated Kaya.
For the time being, aerial AM is a supplement to existing ground-based robotic systems. Drones currently consume eight to ten times more energy and have limited construction capacity. As a result, the researchers recommend a hybrid approach: traditional methods for constructing the lower levels of a structure, with drones taking over at higher elevations to utilize their flexibility and range.
DroneHub
Aerial AM relies on the new DroneHub, located in Empa's NEST research and innovation complex. This multi-environment robotic testbed connects laboratory research with industrial applications.
Kovac added, “Construction drones can be tested here under real-world conditions, further developed, and brought to market maturity.”
The DroneHub plays a key role in the expanded collaboration with Imperial College London and supports the newly established joint professorship in Sustainability Robotics between Empa and EPFL. This infrastructure, which is exclusive to Europe, enables the testing of flying construction machines outside of a lab environment. The first field trials are scheduled for this year.
Journal Reference:
Kaya, Y. F., et al. (2025) Aerial additive manufacturing: Toward on-site building construction with aerial robots. Science Robotics. doi.org/10.1126/scirobotics.ado6251