With an ever growing population, comes the need for continual construction projects.  People need homes, places to work, shop, relax, and so much more.  In any given town or city there will undoubtedly be some kind of ongoing construction project.  These projects take a lot of time, money and resources.  Lately construction teams have been getting aid from drones in a number of different ways.  They are doing everything from surveying sites to monitoring safety and theft concerns, inspecting delicate infrastructures, inspecting for stability, and even going on to help sell a new property.  For the most part, the jobs drones are tasked with on construction sites are a means for assisting workers already in place to preform their jobs with greater accuracy, speed, and safety.  But what if a drone could autonomously build a free standing structure?

Swiss Federal Institute of Technology (ETH Zurich) located in Zurich, Germany is overseeing a project, called the Aerial Construction project, that will test the possibility of drones that can work to build structures.  According to their website, “The Aerial Construction project is a collaboration between the Institute for Dynamic Systems and Control and the Chair of Architecture and Digital Fabrication. The objective is to investigate and develop methods and techniques for robotic aerial construction.”  This is a study that has been going on since 2012, but has begun to pick up speed as drone technology advances.

As stated in the project description, “The pursuit is multidisciplinary, requiring the development of nonstandard material systems, advanced digital design and construction processes, and adaptive strategies for controlling the aerial robots as they interact with their environment and cooperate in the assembly task. Because the structures produced in this framework will be less constrained by conventional assembly parameters (such as, for example, the need of scaffolding to build from the ground upward), we expect that our work will foster new forms of architecture and construction method.”

They are not creating buildings to house offices or shopping centers just yet.  True, drones can be of great value when being used to aid on a building construction site, but when it comes to being able to carry building materials they are very limited.  Most drones can only carry a small pay load.  To run the experiment researchers focused on how a drone could be use to fully construct tensile structures.  A tensile structure is one that is built using tension rather than compression or bending.  An example would be the soft shell like roof that looks like it is being stretched to cover a stadium.  Or more commonly, the structure used to build many bridges.

The tensile structure the team at ETH Zurich settled on for this project was a rope bridge.  Though that may not seem like an architectural wonder, it is a sound place to begin testing theories on how drones can be used to build other structures.  Their research states, “a rope bridge that can support the crossing of a person was assembled by quadrocopters. The rope bridge acts as a demonstrator, showing for the first time that small flying machines are capable of autonomously realizing load-bearing structures at full-scale and proceeding a step further towards real-world scenarios.”

The drones were equipped with a motorized spool that gave them the ability to control the tension placed on the rope as they deployed it.  The rope for the bridge was threaded through a plastic tube on the drone to assure accurate placement.  The rope being used, Dyneema, has a low weight with a high strength making it the perfect material for this job.  A 120m of rope was use to build the 7.4m long bridge made up of 9 rope segments.  The drones constructed the bridge between two scaffolds and included additional elements like knots, braids, and links.

Though drones are not yet ready to build the next skyscraper, this project has gone a long way to show just how much work a drone can do on it’s own.  But perhaps the most valuable lesson the researchers gathered from this trial was how drones interact with an environment and how they interact with people in that environment.  The website goes on to say, “Reliable and safe physical interaction with UAVs will be of great importance in real world applications, where robots will tightly cooperate with humans, such as, for example, on a construction sit.”