This is a similar technique we use for architectural scanning, except the you can use your scan and cad together to get a final result.brianpgreen wrote:First a qualification. I've not actually done this but I believe it will work better than trying to eyeball the transformation using the workspace transformation controls.
Identify 3 points in your cad file that you can also identify in the scans.
Create a .csv file containing the coordinates of the 3 points from your cad file
Mark the corresponding points in the scans.
Import the .csv file on the workspace level. (Drag it into your Scene window)
Create a cluster at the top level of your workspace.
Place your scans in a sub cluster.
Lock all of the scan managers below the top level. (You don't want to reregister your whole project, just move it to your coordinate system)
Use the command "place scans" using target based registration on the top level.
Scene hopefully will find the correspondences and translate and rotate your scan project to your coordinate system.
(We use autocad)
Pick 3 or more reference points in the scan (Doesn't matter which ones, just ones that have good data).
We are only concerned with the X and Y coordinate. Once placed manually set the Z value to 0.
Export objects as DXFs
Export low res pointcloud convert to RCS
open/import into autocad align the objects and the point clouds to the position you want it to be in.
Delete everything except the 3 (or more) points that are your reference points.
You can use data extraction if doing many reference points to create a CSV, or manually create a CSV file using the point locations (Z should be at 0, its easier to do the Z adjustment in scene using the highest folders transform)
Import into scene as references and place scans using targets.
Scene should rotate to your desired alignment.