new ro Civil 3d 2010-how to compare a building face as-built to a 3D mesh

[alderney]

ok long title! I am new to Civil 3D 2010, i also use LDD04 because I am stubborn. My background is surveying and 2D except for some basic grading & contouring.

My situation:

We have laser scanned the 4 faces of a building's exterior. The scan came as an IGES file, which was converted through ACAD Mechanical to an autocad .dwg file. I now have a drawing with 3d faces.

I need to compare the as-built of the building facade to a vertical & horizontal baseline. What is step 1? create a surface from the polyface mesh? i've tried that and 2010 crashes, this drawing is huge.

 

i need step-by-step help in a bad way!

if anyone uses msn messenger i am @ nirvine@hotmail.com

 

thanks so very much

Nicole

[sinc]

Not entirely sure what result you're trying to achieve, but Civil 3D surfaces cannot include any vertical faces, and every X-Y coordinate MUST have a unique Z. So from what you've said so far, it does not sound like Surfaces will help you.

[BIGAL]

You could create a cube representing your compare building and then compare two surfaces.

 

A hint though you can not have a surface with true vertical faces it will give you screwy answers. To correct this problem you need to move the top points off vertical if it was metric then 1mm which is probably way smaller than your tolerance.

 

Ok better answer !! easy way to correct vertical problem disregrading crashing problem if you rotate3d so your lasered face is now flat in the XY plane you just create a normal surface. Then create a new surface with 1 ht say 0.0 then compare (you only need say 5 points for the 0.0 surface ) pick a common point to be the origion pt of your laser model and your new surface.

 

Hope this makes sense

 

Had same problem with super quantity of points 4,000,000 crashes.

[BIGAL]

Can you let us know if this is the end of this forum question

 

Did you get it to work ?