mission parameters

PIX4Dmapper
1

Hello All
I have new project for the urban area, the orthomosaic produced will be used to create cad file for the building in this area.
so I want to know

  1. what is the recommended front and side overlap?.
  2. the covered area will be equal to 3 km2 what is the recommended number of GCPs, and what if we used roof of building to installing GCPs is that recommended?.
  3. if we have two mission, how can I measure the overlap between these two missions?
    note: we will use fixed wing drone with 42 MP camera mounted on it.

thank you

2

Hi suhaib,
It is always difficult to say exactly what your overlap should be but I would say that you will want to be at 75% front and side. Since you are flying an urban area I would suggest flying a cross grid with between 10-30 degrees of oblique. This will allow you to image each side of the buildings. You can read more about image acquisition in the article below.
https://support.pix4d.com/hc/en-us/articles/115002471546-Image-acquisition
As for GCPs on the roof, it shouldn’t be a problem. In fact, it might be the best location since it will probably be unobstructed.

As for overlap between missions, I would simply plan to have your last flight lines overlap so there is no questions about the overlap. This will need to be achieved using your selected flight application.

3

Great
Thank you Mike