Sketch Profile inspection for open contours

bryan_lagrange

It would be nice to have a command that you could execute inside a sketch that would highlight open profiles. 

When a profile is closed, Onshape shades the profile. However sometimes when you believe a shape is "closed" it is hard to find the open contour because the open contour is so small you have to draw temporary lines all over the profile to find the area and then you have to zoom in to the smallest of areas to close the profile. I find this issue rises the most with imported non native .dxf files. 

Simple contour profile, temporary lines are an easy work around to find open profile. If importing something like a complex logo from a customer, that you are making a custom sign for, then the temporary lines and zooming in can be a big time consumer.

MBartlett21

I think there is a connected edges option in the create selection dialog that might help.

lougallo

@bryan_lagrange You have this when there is no filled region shown as well.

bryan_lagrange

@MBartlett21 could you show an example? 

MBartlett21

@bryan_lagrange

See image below that shows a closed sketch:

All the edges are highlighted due to their being connected

tim_hess427

I think @bryan_lagrange is asking for a tool that highlights the "gap" that results in an open contour. If there's only one gap between line segments, the selection tool will still be able to select all connected edges, even if they don't create a closed loop. 

On the bright side, if there is more than one gap between line segments, the selection tool would show you the two gaps closest to your selection. 

First image - 1 gap. Selection tool not useful. 
Second image  - 2 gaps (circled in red). Selection tool useful. 

bryan_lagrange

That is what I am looking for @tim_hess427. 

MBartlett21

@tim_hess427
@lougallo
Would the create selection tool be able to highlight the ends of the loop it selects when 'Loop/chain connected' is selected?
This should make finding one gap easier to do

Toshimichi_Oda

Highlight of the ends is a good idea.

But I propose another:
'create selection' searches one side direction from selected edge instead of both sides.

When chain of edges is not closed, You can find the end at stopping 'create selection'.

If you zoom in clicking a edge, without zoom out you can see either edges' chain closed or not.

It may have a option to select one of three:
  * one side  (longer side)
  * another side  (shorter side)
  * both side

Or it is better than the above option, to have a part-of-chain 'create selection':
Click an edge =A=, and click an edge =B= which is on longer or shorter chain from =A=, then it selects part-of-chain edges from =A= to =B=.

This part-of-chain can be used in edges of face.

john_mcclary

I like it. This would be very useful either way

beats sketching a line and sliding over the sketch until the shading goes away.

Tim's method would probably be better, that way you don't have to click a line first, and you can zoom out and see 'all of the problem areas'
especially when you have an imported DXF with hundreds of gaps

Greg_Keosayian

I would greatly appreciate this tool. Right now I am having to play detective drawing lines and narrowing down the small gap culprit in a sketch which greatly reduces my productivity when I would love to simply extrude this quickly and move on. 

Greg_Keosayian

Greg_Keosayian

Wouldn't it be nice to click a button and the gaps are highlighted in red to save the user time

S1mon

@Greg_Keosayian

I assume you know about the divide and conquer approach (aka binary search) where you add a line in the middle and see which side closes up, and then move the line to the 1/4 or 3/4 point to keep narrowing down the search. Also displaying constraints can help see where the points are coincident.

All that said, a red highlight like we can turn on for open edges of surfaces would save a lot of time.

jon_sorrells

Here's a custom feature that will show sketch line endpoints that are not touching anything else.

https://cad.onshape.com/documents/4fa113c6594cd037bfa214da/v/e5f9020158b188b1ec33530d/e/30010656480b133cd4dcad6d

shawn_crocker

I recognize I may not have fully read everything here but this is how I usually get to the bottom of this issue.

richard_foster236

Thank you @jon_sorrells, that script was extremely useful. I have no idea if it's possible or not, but one small enhancement would be to track the zoom level so the indicator remains visible as folk get closer to the problem. I had a file where the mismatch was extremely small (does 0.001m seem plausible?) and for the last few steps the indicator was no longer visible to help guide me to the exact location of the problem.

S1mon

0.001 m is one mm. Onshape goes to 1 µm (or 0.000001 m). One micron is enough to be a mismatch. It's also enough to work around the zero thickness Parasolid issue.

ben_ferguson976

Well, that script is a life saver --- imported a dxf that was converted from a png, and without the script, I dont think i could have possibly found all these gaps. haha

Javier_López_del_Pueyo

S1mon said:

@Greg_Keosayian

I assume you know about the divide and conquer approach (aka binary search) where you add a line in the middle and see which side closes up, and then move the line to the 1/4 or 3/4 point to keep narrowing down the search. Also displaying constraints can help see where the points are coincident.

All that said, a red highlight like we can turn on for open edges of surfaces would save a lot of time.

Damn! I was having a tough time trying to find the one open spot in my chain and this is actually very smart. Thanks! You saved me a lot of inspection time!