Hi everyone, for an infrastructure project I am modeling a tunnel and its deterioration. The goal is to create a digital twin of the gallery.
My starting data are:
laser scanner survey of the tunnel,
historical sections,
degradation mapping.
At present I have reconstructed the geometry and its development using a script.
Now the client wants the representation of the degradation from a dwg file. In this file the degradation is represented “in true form”, i.e. by “stretching” the length of the arc of the tunnel section.
At first I tried to project the degradation (polylines and closed curves) onto the plane of the ring. This solution works but it allows me to only make vertical projections, along the Z vector (screen attached).
Example: the cap has a radius of 5m, the width of the cap area in the dwg file is more than 18m.
the solution would be to “stretch” the dwg along the circumference of the ring.
Hi @RMohareb, the goal is to represent the degradation as done in the attached image. the problem is that model is obtained by projecting the polylines and areas present along the Z axis. but the starting dwg, in plan view, is wider than the ring, as it represents the “stretched” ring in plan view.
in this way the cracks represented at the height of the wall and the spots drawn on the dwg at the ends (therefore just above the pavement) are not represented (circled in green in the screen).
As the deterioration was mapped in two dimensions, we can only assume it was projected down onto the base plane. So projecting on the Z axis (the opposite of how it was flattened) is the solution.
From the attached screen you can see that I projected the deterioration spots along the z axis. the problem is that in this way I cannot project all the degradation present in the dwg; in particular the one below the centerline of the ring. I do not know if I was clear
How do you know which is below the center line by looking at the DWG?
Use that information to filter your degradation data into lists which are above the center point and those which are below. Project the ones above the center point as before, and project the ones below on the inverted z axis and you should be all set. Note that you’ll have some really odd looking conditions when you have an area which crosses the center plane, but it should resolve once cleaned up.
Thank you all for the support. I solved it by converting the points on the 2D dwg from Cartesian coordinates to polar coordinates. the next step will now be to convert the lines into degradation families (cracks, stains, etc.)
Nice use of polar coordinates; I am still confused as to how you know when a point is at 170 degrees or 190 degrees about the local axis. Was that included in the dataset?
@jacob.small thanks for your reply.
to solve the problem of the points below the horizontal axis I modified the orientation of the coordinate system so as to make it coincide with the beginning of the ring’s circumference
