Sketcher solver redundancy error

[kisolre]

In the attached file when editing Sketch019 suddenly the solver starts reporting redundant constraints. When the reported redundancy is removed the next constraint is reported as redundant and so on. Sma happened with Sketch018 where I had to remove the CarbonCopied reference geometry from another body and CarbonCopy it again to fix the problem.

SketcherError.JPG (109.39 KiB) Viewed 1788 times

Code: Select all

OS: Windows 8.1
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.16493 (Git)
Build type: Release
Branch: master
Hash: 612f5206c1919e623f35b612a9c54f37145f90a6
Python version: 3.6.6
Qt version: 5.6.2
Coin version: 4.0.0a
OCC version: 7.3.0
Locale: Bulgarian/Bulgaria (bg_BG)

[bejant]

In the attached file when editing Sketch019 suddenly the solver starts reporting redundant constraints. When the reported redundancy is removed the next constraint is reported as redundant and so on

Confirmed here. Running the ForceRecompute macro shows several Errors upstream, and I have to wonder if those Errors are contributing to the Solver problems.



OS: Ubuntu 18.04.2 LTS
Word size of OS: 32-bit
Word size of FreeCAD: 32-bit
Version: 0.18.16093 (Git)
Build type: Release
Branch: releases/FreeCAD-0-18
Hash: 690774c0effe4fd7b8d2b5e2fb2b8c8d145e21ce
Python version: 2.7.15rc1
Qt version: 5.9.5
Coin version: 4.0.0a
OCC version: 7.3.0
Locale: English/UnitedStates (en_US)

[chrisb]

The proposed for deletion constraint48 is obviously not redundant, it's the only constraint of that construction line.

We have seen this here in the forum before, you may search the sketcher tickets for them. IIRC it was caused by a previously undetected redundancy, which can mean two things:
- This is an old design which you are editing or completing with a current version
- You have added more constraints when there was already an error shown.

Does one of these conditions hold?

[chrisb]

I found the discussion where subsequent deletion of constraints was requested by the solver. The corresponding ticket issue #3529 was fixed.

[kisolre]

- This is an old design which you are editing or completing with a current version

No, it was started with 0.19 and the info is for latest 0.19 because I wanted to check that it will still happen with the lates version and after save.

- You have added more constraints when there was already an error shown.

I probably added a tangancy constraint between the slanted construction line and the arc not realizing that it might already have one (not sure on this) ant there came the first redundancy message. After Undo it showed a long list of "Remove at least one" constraints and then started this.
There are no driven constraints and havent been in that sketch (the bug report)

ForceRecompute macro shows several Errors upstream,

Where do you see those errors? Treeview shows error only on Sketch019, Report view shows only blue messages.

[Willem]

I found that deleting Coincident constraint 49 makes the sketch valid. I did not investigate why

[kisolre]

I found that deleting Coincident constraint 49 makes the sketch valid. I did not investigate why

You are correct. There are "Point to point tangency" and Coincidence constraints there. And probably as in the bugreport Chrisb mentioned the wrong index is reported. Should the ticket be reopened?

[chrisb]

Yes I think so. This is sure something Abdullah wants to have a look at.

[kisolre]

I am not sure how to reopen the ticket so

care to take a look?

[meme2704]

You are correct. There are "Point to point tangency" and Coincidence constraints there. And probably as in the bugreport Chrisb mentioned the wrong index is reported. Should the ticket be reopened?

I wanted to talk about this problem on another post I was told that I am an old grump incompetent
I find that others more competent than me have the same thing
I have seen it even with a new project of a few segments and arcs and each time it is the tool of tangential constraints that crash