View Issue Details
|ID||Project||Category||View Status||Date Submitted||Last Update|
|0000691||Sketcher||Bug||public||2012-05-01 23:12||2013-02-13 13:18|
|Fixed in Version||0.13|
|Summary||0000691: Sketcher: Symmetry constraint broken for arc endpoints|
|Description||Symmetry constraint is broken for arc endpoints and always results in conflicting constraints error, even if it's the only one in the sketch.|
Tested with both 0857 and 0899. It works fine in 0.12.
|Tags||No tags attached.|
symmetry-bug.FCStd (2,719 bytes)
||Actually, that's incorrect. The file I attached does NOT work in 0.12. It seems that making the arc centre and one of the line's points coincident triggers the error. Both 0.12 and 0.13 can enforce the symmetry otherwise. It used to work before, as demonstrated by http://freecad-tutorial.blogspot.com/2011/09/engine-1-piston-pin-and-pin-ring.html|
I have a sketch that may shed some light on what's happening.
See uploaded file: MirrorConstraintFailExample.fcstd
The line can not have mirror constraint about Y axis unless horizontal constraint is removed.
Tha arc can not have mirror constraint about Y axis unless point-line constraint between arc center and Y axis is first removed.
A general observation is that it looks like mirror/symmetric constraint wants to remove two degrees of freedom and reults in overconstraint condition if there is only one degree to be removed.
Version: 0.13.0930 (Git)
MirrorConstraintFailExample.fcstd (3,677 bytes)
it should now be fixed in the sketch-diagnostics branch:
which needs some more testing and polishing before merged to master.
Version: 0.13.0955 (Git)
I tested symmetric constraint in a variety of situations involving arcs and lines. The solver was able to identify redundant constraints. Following manual removal of the redundant constraint(s) the sketches were fully constrained. This greatly enhances the useability of sketcher.
|2012-05-01 23:12||mathrick||New Issue|
|2012-05-01 23:12||mathrick||File Added: symmetry-bug.FCStd|
|2012-05-01 23:57||mathrick||Note Added: 0001991|
|2012-05-05 13:26||djreichel||Note Added: 0002013|
|2012-05-05 13:27||djreichel||File Added: MirrorConstraintFailExample.fcstd|
|2012-05-05 17:50||yorik||Project||FreeCAD => Sketcher|
|2012-05-06 12:40||djreichel||Note Edited: 0002013|
|2012-05-14 07:31||logari81||Note Added: 0002039|
|2012-05-14 10:28||logari81||Assigned To||=> logari81|
|2012-05-14 10:28||logari81||Status||new => confirmed|
|2012-05-14 10:28||logari81||Product Version||0.13 =>|
|2012-05-14 10:29||logari81||Summary||Symmetry constraint broken for arc endpoints => Sketcher: Symmetry constraint broken for arc endpoints|
|2012-05-14 10:30||logari81||Status||confirmed => assigned|
|2012-05-16 01:30||djreichel||Note Added: 0002048|
|2012-05-16 01:46||djreichel||Note Edited: 0002048|
|2012-07-13 09:09||logari81||Status||assigned => resolved|
|2012-07-13 09:09||logari81||Fixed in Version||=> trunk|
|2012-07-13 09:09||logari81||Resolution||open => fixed|
|2012-07-14 08:57||wmayer||Status||resolved => closed|
|2013-02-13 13:18||yorik||Fixed in Version||trunk => 0.13|