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Excluding overhead structures from volume analysis?

Since Pix4D tech support is slow at responding, does anyone know how to exclude overhead structures from a volume analysis. I have a large stockpile which has conveyor systems overhead - when I perform a volume analysis of the pile under the conveyors, Pix4D assumes the volume includes the overhead conveyor system. Does anyone know how to ‘trim’ a volume to exclude certain areas?

The area in question: http://imgur.com/WdUac2G

The resulting volume analysis: http://imgur.com/PK4VrE7

Figured it out - any overhead structure or point that you don’t want included in the volumetric calculation must be moved to the ‘deleted’ point group.

Hudson Chalmers

Select stockpile again and measure around the structure and subtract the returned volume from original.

Hey Mark, if you dont mind me asking.

Me and a partner just started a drone solutions business in Panama and are trying to figure out how much to charge clients.

Could you help us out? we don’t know if to charge by visit or by flight? and how much is the average charge for it?

Any help is apreciated 

 

Thanks!

 

Joey

 

 

Joey, email me at mblacklin@cgrs.com and I’ll try to help you out

Appears as though this feature is ‘broken’ in 2.1.52

Agreed: this was working in earlier versions, but now it keeps the overhanging points in the volume object for conveyors.

 

PLEASE FIX ASAP!!!

Hi Mark and John,

Thank you very much for reporting this bug.
There is indeed an issue with the deleted points that are taken into account to generate the DSM that is used for volume calculations in Pix4Dmapper 2.1. Our developers could fix it and a new build will soon be released but we cannot provide an exact date.

Regards,

John and others,

As you may have seen on the Facebook Pix4D Users Group, the new version uses the DSM instead of the point cloud for volume calculations. In order to use the point cloud, you need to close the project, and move the ortho folder (from step 3) to a place where Pix4D doesn’t recognize it. Usually I just move it to my desktop temporarily. Then reopen the project, and you’ll see that it looks like step 3 hasn’t been processed. This forces Pix4D to now use the point cloud instead of the DTM for calculations. If you’ve moved points to the deleted group, they won’t be used for the volume calculations. Hope this helps.

+1 on this.  I have numerous instances where I have conveyors over piles and the volume measurement gets screwy.  Is there a way to move items to the deleted group and still use the DSM for the volume measurement?

I was just here looking for a similar type of answer.  I have a cylindrical water tower with a domed roof.  I know from the manufacturer that the volume of water is only 3/4 of the vertical height but when I calculate the volume it includes all of the volume right up to the base of the domed roof, which is inaccurate for my case.

I was wanting to know how I could limit the volume calculation to stop at the correct elevation as per the manufacturers dimensions and not go right to the roof?  Seems like Marks work around would be best but it seems very tedious for such a sophisticated software package.  Being a GIS Specialist myself, it seems like we should just be able to create a Mask over the area to not include in the calculations.

I am using version 2.2, is the DSM still used and not the Point Cloud for volumetrics?

Using version 2.2 I was able to Delete points in the point cloud and than regenerate the DSM and the resultant volume calculation did not take in to account the Deleted points.  I am not getting a good result of my cylindrical water tower with the top 1/4 deleted.  I was hoping the volume calculation would go from the base to the flat surface where the Deleted points were, but instead the interior volume calculation is sporatic and not complete and I only get a partial result of the volume calculation.

Hello guys,I had the same problem but I am now using the 3.1. and is fine.

They say how to remove objects. Check it out: https://support.pix4d.com/hc/en-us/articles/218022903

Cheers, J.P.