FRAC Centre
Flight Assembled Architecture, a collaboration with architects Gramazio & Kohler, is an exploration of aerial construction. Conceived as a 1:100 model of a 600-meter high vertical village, the four-day-long live exhibition featured four quadcopters building a 6-meter tall tower out of 1500 foam bricks. The exhibition took place at the FRAC Centre in Orléans, France from December 1st to 4th, 2011. The FRAC Centre is an architectural art museum on the outskirts of Paris that promotes contemporary art, both nationally and internationally. During the opening night, the museum hosted 300 enthusiastic people. Learn more about Flying Machine Enabled Construction below.
![FAA_Orleans_2](https://i0.wp.com/www.flyingmachinearena.ethz.ch/wp-content/uploads/2024/03/FAA_Orleans_2.jpg?resize=799%2C329&ssl=1)
System Architecture
![A system diagram of how the different subsystems interact.](https://i0.wp.com/www.flyingmachinearena.ethz.ch/wp-content/uploads/2024/05/architecture.jpg?resize=600%2C143&ssl=1)
The Blueprint
The Blueprint is a file that establishes how the structure will be constructed. It holds information such as brick location and the order in which parts should be assembled.
The Foreman
The Foreman manages the overall construction process by interpreting the blueprint, issuing build orders to the Crew, and tracking the construction progress based on their feedback. It is also how the system interfaces with the outside world via a user interface. Using the Foreman, the number of flying vehicles in flight at any one time, as well as the rate (in Bricks Per Hour) can be controlled.
The Crew
The Crew is responsible for interpreting the Foreman’s build orders and based on these, building the structure. The Crew subsystem manages the flying machines at all levels, including coordinating recharges, planning trajectories with collision avoidance, managing the pick-up and placement of bricks, and generally controlling the in-flight dynamics.
The Configuration
The configuration file contains the operational parameters, such as the usable space dimensions, flight “freeway” definitions, and properties of the building materials. It also includes parameters relating to system behavior such as pickup/placement tolerances, flight speed & aggressiveness, and parameters to control battery management.
Collision Avoidance and Freeway-Based Flight
To coordinate flying and avoid collisions, the vehicles use two freeways that encircle the structure. Usage of the freeways is controlled by a space-reservation system, whereby each vehicle reserves the space required for a trajectory before the trajectory is flown. This space is then unreserved once the trajectory is completed. This system ensures that while a space is reserved, only the reserving flying vehicle has access – all other vehicles must wait before flying through this space.
This system is also used to stop collisions with the tower. In this situation, the entire tower is reserved, thus preventing any vehicle from planning a trajectory through this space.
Both freeways as well as the space reservation system can be seen in the image, where the black and red “tubes” represent space reserved for each trajectory – one on each freeway.
![The reservation system that prevents flying machine collisions with the tower and with other flying machines.](https://i0.wp.com/www.flyingmachinearena.ethz.ch/wp-content/uploads/2024/05/FRAC_plan.jpg?resize=600%2C407&ssl=1)
Gripping and Placing Bricks
To grip bricks, a specialized gripper was developed. This gripper uses three, servo-powered pins to puncture and hold the brick.
Being able to accurately and reliably place a brick is fundamental to a successful construction. Many ideas, iterations, and fine-tuning showed that the most accurate and reliable method of placing a brick is to “fly” it quickly into place, avoiding significant disturbance due to turbulences or ground effect.
Starting at a specified distance above the brick, the vehicle plans a trajectory that will result in the brick being flown into the structure with a specified velocity. Testing showed that lower impact velocities (and thus gentler landings), were significantly affected by turbulence and ground-effect around the structure. For this reason, a faster and more aggressive impact is favored.
![A rendering of the gripper used by the flying machines to puncture and hold a brick.](https://i0.wp.com/www.flyingmachinearena.ethz.ch/wp-content/uploads/2024/05/FRAC_gripper.jpg?resize=600%2C425&ssl=1)
Publication, Credits, and Press
Publication
Federico Augugliaro, Sergei Lupashin, Michael Hamer, Cason Male, Markus Hehn, Mark W. Mueller, Jan Willmann, Fabio Gramazio, Matthias Kohler, and Raffaello D’Andrea, “The Flight Assembled Architecture Installation: Cooperative construction with flying machines”, IEEE Control Systems Magazine, Volume 34, Issue 4, 2014, pp. 46 – 64
Pdf | Bibtex
Participants
The following participants worked on the Flying Machine Enabled Construction project from the summer of 2010 to the winter of 2011:
Federico Augugliaro
Marc-Andrè Corzillius
Carolina Flores
Michael Hamer
Markus Hehn
Sergei Lupashin
Cason Male
Mark Mueller
Igor Thommen
Prof. Raffaello D’Andrea
Gallery
The charging stations allow for the construction by the quadcopter crew to be continuous from start to finish.
© François Lauginie
![idsc_eth_logo](https://i0.wp.com/www.flyingmachinearena.ethz.ch/wp-content/uploads/2024/04/idsc_eth_logo.png?resize=1080%2C342&ssl=1)