Nymølle Gravel (Grusgrav)
We went to a gravel, at Nymølle at Zealand Denmark to test our LiDAR scanner on volume calculation against traditional photogrammetry. The area is a production site and trucks constantly arrives/leaves the site with gravel. This creates some dust in the air, although not visible on below video, it's something you notice at the site. At the test day the weather was good and no clouds on the sky. This is not something that will affect the LiDAR scan, but it is normally something that create difficulties for photogrammetry. So for reference the weather were noticed.
On the overflight, on below video, it is worth noticing that some of the pile is in the shade, normally a challenge for photogrammetry.
For the volume estimation you can either consider the ground of the dirt pile flat or with a slope plane. In both cases we get a lower total volume with LiDAR.
In the overflight of the big dirt pile, we find, comparing LiDAR with photogrammetry from a flat plane, that LiDAR returns a volume 1067 m3 or 3,1% lower than photogrammetry. Making the same calculation on a slope plane we get 914 m3 or 2,99% lower in the LiDAR compared to photogrammetry. We were not given another reference volume but the total is around 30.000 m3.
In both cases the lower results are more accurate volume calculation, and is something very important for Nymølle, because this allows them be better estimate how much they have in stock.
Below is a comparison between the LiDAR and Photogrammetry scan, from the same area. It is clear that on photogrammetry that some data are missing.
Imagine what a better volume estimate can do to your process?
/Thanks to Upteko for flying and Nymølle Stenindustri for access to their premises.