A drone that ties rebar together.

When we hear about drones in the construction industry, it usually has to do with site surveying or inspection. But here’s an aircraft that actually builds: a drone that ties rebar together.

I’ve never tried tying rebar, but it looks about as much fun as picking strawberries. Bend over, stay that way for hours, wonder why you can barely move the next day. There are machines that can do this repetitive and painful work, but they need 40-foot trailers to haul them to the construction site and cost hundreds of thousands of dollars. The SkyTy system promises huge improvements in both speed and cost when it comes to this laborious chore.

The concept actually uses a number of drones. A mapper drone flies over the site, building a picture of the rebar mesh and identifying the intersections. Using those coordinates, multiple drones can be deployed to do the actual tying and automatically keeping out of one…