The use of 3D printing in the construction industry is gaining in importance. Both on the construction site and in the factory, static and mobile robots print materials for use in construction projects such as steel and concrete structures.
A new approach to 3D printing, developed by Imperial College London and Empa, the Swiss Materials Testing and Research Institute, uses flying robots called drones that use collective construction methods inspired by natural builders like bees and wasps are.
The system, called Aerial Additive Manufacturing (Aerial-AM), involves a fleet of drones working together on a single design.
It consists of BuilDrones that deposit materials during flight and quality control ScanDrones that continuously measure the performance of the BuilDrones and inform their next manufacturing steps.
The researchers say that, unlike alternative methods, in-flight 3D printing opens doors that lead to on-site manufacturing and construction in hard-to-reach or dangerous locations, such as.
The research was led by Professor Mirko Kovac from Imperial’s Department of Aeronautics and Empa’s Material and Technology Center for Robotics.
“We proved the concept that drones can work autonomously and in tandem to build and repair buildings, at least in the lab,” says Kovac. “This scalable solution could support construction and repair work in hard-to-reach areas such as tall buildings.”
Aerial-AM uses both a 3D printing and path planning framework to allow the drones to adapt to variations in the structure’s geometry as construction progresses.
The drones fly completely autonomously, but there is a human controller in the loop who can monitor progress and intervene if necessary based on information provided by the drones.
Printing 3D geometries
The researchers developed four cement-like mixtures that the drones can use to build.
The drones evaluate the printed geometry in real time and adjust their behavior to ensure they meet build specifications, with a manufacturing accuracy of five millimeters throughout the building.
The proof-of-concept prints included a 2.05-meter cylinder (72 layers) with a polyurethane-based foam material and an 18-centimeter cylinder (28 layers) with a custom cement-like structural material.
The technology offers future opportunities for building and repairing structures in boundless, high or other hard-to-reach places. Next, researchers will work with construction companies to validate the solutions and provide repair and manufacturing capabilities. They believe the technology will offer significant cost savings and reduce access risks compared to traditional manual methods.
The co-investigators include Robert Stuart-Smith, Stefan Leutenegger, Vijay Pawar, Richard Ball, Chris Williams and Paul Shephard, and their research teams at UCL, the University of Bath, the University of Pennsylvania, Queen Mary University and the University of Munich .
This work was funded by the Engineering and Physical Sciences Research Council, part of UKRI. It was created by assistant professors Stuart-Smith and Kovac after a pilot research collaboration and an award for a pipeline repair demonstration. The project is also supported by industry partners Skanska, Ultimaker, Burohappold and BRE.