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View Full Version : 3D Scans and Revit



mattw
2012-01-09, 06:52 PM
Does anyone have any experience with 3D scans and bringing that data in Revit? Let's say you scan a mechanical room. Does the scanned data somehow translate to individual 3D elements or is it one giant blob of..... stuff?

We're working on a job that will require us to model all of the existing pipes, valves, ducts, etc. in a mechanical room. Some of it will be demo'd at a later date.

Does anyone have any links to any manufacturers and/or software vendors for 3D scanning?

Thanks in advance!!
Matt

tbodor
2012-01-10, 04:01 PM
I do have some experience with laser scanning and Revit. The points of the cloud have no intellegence other than knowing where they are in an x, y, and z space. The points don't know if they belong to a pipe or a wall. You will need to do the modeling of the elements.

I've worked with vendors and have done my own scanning with a Faro scanner. I prefer to do my own scanning so I can control what is scanned and I can get a feel for the area scanned (as I'm the one doing the modeling a well)

The Scan to BIM module by ImaginIT is very helpful but not 100% necessary. There are others I'm sure. Depends on the scanner your going to use.

One thing to remember is Revit does not like things that are not parallel or perpendicular to much. It also does not like to model piping that sags as well. You'll have to use your best judgment when it comes to your accuracy and final deliverable.

Only model what will be necessary when it comes to demo projects. The scanner is going to scan everthing it sees. The more information the better.

cmhogge
2012-01-10, 05:39 PM
123D Catch by Autodesk LABs may work if you are attempting to simply use it for reference purposes. I am not sure how it interacts with Revit but it is an Autodesk product and it is currently free. I'm looking forward to seeing how this turns out for you, good luck!

jseck
2012-01-13, 01:51 AM
I also have experience with point clouds in Revit. Regarding Scan to BIM, it is very helpful for modeling pipes from point clouds. It allows you to window select a group of points representing a pipe. It then queries the points and finds the best center line. It will report the OD of the pipe, and from that, you can select the matching nominal size. You can then specify the Revit pipe type and size to place on that center line. Of course all bets are off if the piping is insulated, unless you know the insulation thickness. tbodor brings up a good point regarding point clouds. They provide extremely accurate results, way more accurate than you could ever get from physically measuring a mechanical room with a tape measure. Therefore, any sagging or other abnormalities will show up in the scan. For example, if two pipes in the scan form a 89.2 degree angle instead of a true 90, you have to make the call how to model it. Another example is a long pipe run that has a slight slope to it (not drainage pipe). Do you model the exact slope or model it with zero slope and adjust the elevation to split the difference? It's my opinion that attempting to model with 100% accuracy is impossible. I prefer to model pipes with correct angles and no slope, unless it's drain pipe of course.

One piece of advise I will give you: Verify the scale of the point cloud before you start modeling anything! Some formats tend to import in metric units so you need to scale them down. When you select a point cloud and click Edit Type, you can adjust the scale if needed. If the scale read 3.28, odds are you need to change it to 1.0.

mattw
2012-01-13, 02:29 PM
Thanks for the feedback!

Matt