Extracting wires from power lines

PIX4Dmapper PIX4Dmapper Questions/Troubleshooting
1

I´m processing images from a P3A to reconstruct a power line, specially the wires, so far the wires are reconstructed, but it seems tha on the point cloud the reconstruction has match only on the wires separator, not exactly on the wires, however it seems to work, as the algorithms reconstructed them. In other tests the wires appears on the ground, I mean, they appear parcialy reconstructed on the ground surface, but with the color of the wires. The ATP on the images shows that only 2 images has match over the wires and the others on the ground, may this be the issue for this happens?

2

Wires are difficult with photogrammetry anyways, but here’s my input: 

 

* Upgrade your P3A to a P4p or P4a.  The camera is much better and will improve your results. 

*Increase your overlap

*decrease your flight speed to ~10-15mph. 

*fly at 300-400ft AGL.  In my experience, lower altitudes do not improve results on powerlines. 

*Change your “minimum number of matches” in your processing options. Lower values will result in more of the powerline being constructed, but with lower confidence and a lot more noise.  This should be adjusted along with your overlap settings. 

*Don’t use the ortho to draw powerlines, unless you’re using the base of powerpoles as the vertex. 

1 Like
3

Hello, 

Can you tell more about why you need to reconstruct the wires? and what you would do with them afterwards? This will help us understand how we could improve the products to solve this use case. 

Thank you! 

 

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4

Pierangelo Rothenbühler

The first objective of all its simple reconstruct de wires, and after this, measure the distance from the wires to vegetation!

5

Derrick Westoby

 

My overlap is 80% front and side, the flight speed is 10, maybe speed its to high, flying at 60-70meters (330 ft)

6

Dji Vant, ok, makes sense! Thanks!

How do you do the measurements to the vegetation? Do you have a specific software? Any specific file export needed?