An octocopter capable of attaching asphalt shingles to roofs with a nail gun has been demonstrated at the University of Michigan, Ann Arbor, according to news.umich.edu.
The autonomous aerial vehicle positions the nail gun on a nailing point, places the nail and moves to the next point without needing a human at the controls.
“For me, the biggest excitement of this work is in recognizing that autonomous, useful, physical interaction and construction tasks are possible with drones,” said Ella Atkins, a professor of aerospace engineering and robotics.
Drones currently can address tasks that pose fall risks by inspecting bridges, wind turbines and cell towers. Atkins said the natural next step is to upgrade from surveillance alone to performing physical tasks.
Atkins’ team used a system of markers and stationary cameras to enable the octocopter to precisely locate itself in space. They used this system to tell the octocopter where the nails should go. To fire the nail gun, they first measured the force needed to compress the point of the nail gun, which must be done before a nail will deploy. They then wrote software that would allow the octocopter to apply that force.
The off-the-shelf version of this electric nail gun requires a trigger to be compressed, as well, but the team turned that into a virtual switch that activated when the octocopter was in position to place a nail.
For now, the drone is slow compared with humans performing roofing work.
“Initially, we tried using faster approach speeds to minimize nailing time,” said Matthew Romano, a robotics Ph.D. student. “However, for those attempts, the nail gun tip often bounced off the roof, which meant it either wouldn’t trigger or it would trigger in the wrong place.”
In addition to speed, the team identified other improvements that would be needed. For example, the drone should be powered by tether rather than battery, which would allow it to run indefinitely. Additionally, an air line running alongside the power cable could make the nail gun a more effective pneumatic model.
A paper regarding this work, “Nailed it: Autonomous roofing with a nailgun-equipped octocopter,” has been submitted to the International Conference on Robotics and Automation. The study was funded by the National Science Foundation.
