Drone mapping saved my job after a 2 hour survey screwup

I was on a commercial site in Austin and my total station kept losing the prism because of all the rebar and equipment around. We burned 2 hours trying to get a baseline shot and the GC was getting annoyed. I finally pulled out an old DJI drone we had in the truck and flew a quick mapping pass over the whole pad. In 20 minutes I had a point cloud and control points that lined up with the drawings. We got the layout done that afternoon and I haven't touched the total station on that site since. Has anyone else switched to photogrammetry for the rough grade layouts? I'm curious what software you use to pull grid points from the mesh.

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the_ben2d ago

The "2 hour survey screwup" bit is doing a lot of heavy lifting there. If the total station was fighting you that bad, the problem wasn't the gear, it was the setup. Rebar and equipment don't just appear mid shot, you scout the line first or set up somewhere cleaner. A drone gives you a pretty picture, sure, but it's not giving you the precision you need for layout stakes. Photogrammetry is great for topo or as-builts, but I've seen guys trust a mesh and end up 0.3 feet off on a footing because the ground shifted between flights. You got lucky the drawings lined up that clean. I'd keep the total station warmed up for the tight stuff.