topic Re: Two Different Flatten Quilt Features? in 3D Part & Assembly Design

Two Different Flatten Quilt Features?

bafoster84 — Fri, 07 Dec 2018 19:52:57 GMT

(Using Creo 3.) A colleague sent a "legacy" part with the below model tree. I am familiar with seeing the flatten quilt feature with the purple icon. When I go to edit the flatten quilt feature above it (circled in blue), a popup menu with options (more than the norm) opens (See below). The two features produce different flattened quilts. The flat produced by the feature circled in blue seems to be more accurate. The problem is I cannot find the feature circled in blue or how to adjust the flatten quilt feature to produce the popup menu. My colleague doesn’t know how the original designer made it. Any thoughts on how I can get these options?

Re: Two Different Flatten Quilt Features?

AmitDeshpande — Tue, 31 Oct 2017 19:15:03 GMT

My guess is that this may be the old Flatten Quilt UI. Since it's part of the legacy model, it hasn't been updated, and is still using the old UI, when attempting to redefine it.

I don't think there is a way to get back to that same UI. Using the menu picks of Model > Surfaces > Flatten-Quilt Deformation, will bring up the new dashboard UI.

You can upload the model and provide the release you are working with, if you would like someone to take a look.

Re: Two Different Flatten Quilt Features?

dgschaefer — Tue, 31 Oct 2017 21:25:02 GMT

I'm using Creo 2 and the screenshot you posted is what I see when usign the flatten quilt feature.

Re: Two Different Flatten Quilt Features?

bafoster84 — Wed, 01 Nov 2017 11:17:33 GMT

When using Creo 3, instead of a popup menu I get a ribbon menu with far less options.

Re: Two Different Flatten Quilt Features?

dgschaefer — Wed, 01 Nov 2017 16:54:07 GMT

Well, I don't understand what any of those options in Creo 2 do or why I'd need to tweak them anyway, so ...

I'd love to better understand this feature because it frequently produces unexpected or distorted results for me.

Re: Two Different Flatten Quilt Features?

dnordin — Wed, 01 Nov 2017 18:00:52 GMT

Out of curiosity, what to you mean by "The flat produced by the feature circled in blue seems to be more accurate."? How are you determining accuracy in a fatten quilt? Are you comparing to actual real physical part inspection values?

We consider this feature as PTC's "guess" at the final geometry, and don't rely on the feature for creating accurate geometry. We often get "bizarre" results.

It would be interesting to see the math/logic behind how PTC shrinks and/or stretches the geometry to produce the fatten quilt.

Regards,

Dan N.

Re: Two Different Flatten Quilt Features?

bafoster84 — Thu, 02 Nov 2017 12:28:14 GMT

I am assuming no deformation of the surface. So theoretically, the surface areas of the complex surface and the flattened surface should be equal (unless my logic is flawed). I compare it to unrolling a tube. The surface area of the rolled tube equals the surface of its unrolled rectangle. I really just “eyeball” the geometric shape the program produces and pay attention to surface area.

I think it has to do with the second fundamental form (shape tensor) but, I have only done a little high level research into it. It is very interesting the geometry the program produces.

Re: Two Different Flatten Quilt Features?

dschenken — Thu, 02 Nov 2017 13:21:30 GMT

I think I already mentioned that for surfaces with 0 Gaussain curvature the flattening should be good; surfaces like cylinders and cones. For surfaces that have non-zero Gaussian curvature, such as toroids, there are no methods to flatten them without distortion.

Re: Two Different Flatten Quilt Features?

bafoster84 — Thu, 02 Nov 2017 13:26:07 GMT

Yes, you did! I guess we got back on the same topic.

https://community.ptc.com/t5/Additional-Creo-Questions/Wondering-about-the-math-behind-surfacing/m-p/488700#M39004