Italian studio Carlo Ratti Associati used a swarm of drones to graffiti this artwork in Turin that is based on visual content submitted by hundreds of contributors.

The large-scale painting measuring 14 by 12 metres was developed as part of UFO Urban Flying Opera, a participatory technology and art project funded by Turin-based arts and business foundation Compagnia di San Paolo.

The vertical graffiti was created by four unmanned aerial vehicles (UAVs) flying simultaneously over the course of two consecutive days.

Each drone carried a tank of sustainable spray paint and sketched designs onto a canvas installed in the city's Aurelio Peccei park, inside an industrial structure that previously belonged to Italian car manufacturer Iveco.

The final painting comprises three layers; a grey one that sets the story, a magenta layer that represents Torino's communities and public spaces, and a light blue one that ties together elements of the narrative.

The studio, which is headed by architect Carlo Ratti and based in Turin, collaborated on the project with local research and innovation organisation Links, as well as Russian firm Tsuru Robotics.

The drones were controlled by a central management system and a monitoring system tracked their precise location to enable real-time coordination across the entire formation.

According to its creators, the project represents the first example of drones being used to create a collaborative artwork on a vertical surface.

More than a thousand participants submitted their visions for the future of cities to the project's organisers, who worked with the University of Turin and the Polytechnic University of Turin to select around 100 examples for inclusion in the final design.

"The city is an open canvas, where people can inscribe their stories in many ways," said Carlo Ratti, who is also director of the Senseable City Lab at the Massachusetts Institute of Technology (MIT).

"Such processes have always been happening; however, with UFO we tried to accelerate them, using drone technology to allow for a new use of painting as a means of expression."

An early version of the concept featured in Dezeen's award-winning documentary Elevation, which explores the many potential applications for unmanned aerial vehicles. The film features insight from leading architects, designers and researchers discussing the role of drones in future society.

The UFO project is an evolution of Carlo Ratti Associati's research into vertical drawing and participatory design, and particularly its Paint By Drone system, which uses flying robots to create artworks on the sides of buildings.

"The project is inherently participatory, and is about hacking the city," said Antonio Atripaldi, project manager and partner at Carlo Ratti Associati.

"It allows us to consider people's input, and build new initiatives around bottom-up contributions. For cities, this means residents can reclaim, beautify and leave their mark on the space they inhabit."

Carlo Ratti Associati has established an international reputation for projects ranging in scale from furniture to urban masterplans, which merge design with cutting-edge digital technologies to examine ways in which technology can enhance everyday life.

The studio's previous projects include an internet-connected robot that can write or draw on any surface, and a proposal for an autonomous robotic bar that would make cocktails for city dwellers wherever they are.