After upgrading Emlid flow to allow for staking surfaces, my cut/fill number is incorrect for linework and points. Staking to the surface results in a correct value of cut/fill.
The elevation shown on the stakeout page is correct, and when recording points it saves the correct value
You can see I am staking out point 19, which has an elevation of 909.098m, and I am staking on top of a road, with an elevation of 911.495m. It should show a cut of 2.397. But shows a Cut of 0.358m ???
When staking to other lines the cuts and fills do not change by a relative amount either. The top of the wall line work is ~2.8m higher than the lower one, but it showed a cut of ~0.30m?
This was 100% working the day before I updated Emlid Flow. No settings have changed on the base or rover. I can provide logs if required.
Seems like the staking feature isn’t displaying the correct cut/fill. So something in the background calculations isn’t right. Is this difference of display error of 2.039m the same for other points?
No that’s the really frustrating part. It’s not the same error offset between lines.
If I could just add 1.5m or 2.039m that would be annoying, but easier.
Hi @millsy.g, the way staking to a DTM works right now is it treats all linework as 2D and takes the elevations from the DTM. Could this be the source of the error that you are observing? Could you try to deactivate the DTM and check that this way staking to a line gives you expected cut/fill values?
When building this feature, we were under impression that on a DTM only the surface elevations matter, maybe we didn’t get it correctly and a way to quickly switch is required? Could you please add more context to when do you need to use both surface elevations and linework elevations? That would really help us better understand how to improve this workflow.
Having noticed this a few days ago, I thought something was going on.
Surfaces are usually the final earthworks levels. Linework could be coincident with the Surface for things like kerb alignments/levels or swale alignments perhaps, however they are not for things like subsurface features like drainage alignments. If I am staking a drainage line, I am more interested in my depth to it, not so much the surface, but for me it would be good to know how this would relate to the final cut/fill that might need to occur next and to catch an errors for depth of cover. So maybe while staking linework with (or without) elevations a smaller indicator in relation to cut/fill would be convenient?
While we are at it, can we introduce a feature to set a null value for elevations? There is a program we use here called 12d which uses -999 as a null value for elevation (I would think other programs might have different values). That way I wouldn’t have to enter a different elevation (say 10m below or 0) for the line/point and it could then be assumed as fixed surface? Hope that makes sense?
The case for line work having elevations does make sense. A lot of times staking for roadway alignment we usually just stake the center for preliminary clearing and rough grading. Most if the time station intervals need to be changed on the fly per contractor requests in the field. Having the centerline, road edges or center ditch lines with elevations makes the job a lot easier as you can stake to the line at whatever interval that’s needed.
Can learn a lot from obtaining professional survey software that has been around forever to replicate every feature and put your own spin on it. Will need to definitely ramp up developer manpower.
Appreciate all your comments here, we will think how we can improve this workflow. Just wanted to point out that there is a small surface icon near the cut/fill value. If it is shown, it means that the values are relative to a DTM.
For now, the workaround is to go surface → deactivate, that would allow you to work with linework being 3D as usual.
We are now working on improvements to this feature, including entering vertical offsets. @joelbladen not sure if having a way to enter an offset is what you meant? If not, could you please give an example, so that I can wrap my head around this
Thanks a lot for your feedback, we love learning how you use Flow in the field and how we can improve the software to work better for you!
Just a heads up that we have just released a new version of Emlid Flow that let’s you see both the cut/fill value to the geometry and to the DTM. Along with offsets and other improvements.
So I have had a chance to get and test the new feature.
It works great!
If I had one thing that I would change, I would add the name of the active surface. Without going back and checking, I can’t verify that I’ve selected the right surface.
I have asked before… could we get an option to display the elevation in feet rather than meters?
I desperately need to be able to read the elevation in feet as I’m staking. I can go back to edit the points and see the feet, but I need to see it in real time as I stake.
I have my preferences set to feet, but it doesn’t change the live reading during staking.
