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simple sketch not able to be constrained (by tsk)
Hi there,
I'm playing around with solvespace by trying to constrain a simple sketch I found in a paper about constraint solvers.
I can draw the sketch and set some constraints, but I cannot add missing constraints without getting the "SOLVE FAILED!unsolvable constraints" message.
E.g. try to add perpendicular constraintes at the two straight line corners...
Even in the not fully constrained sketch I cannot move lines or some points.
Is there a problem with the sketch or do I hit the edge of solvespace's capabilities?
Attached the sketch.
tsk
I'm playing around with solvespace by trying to constrain a simple sketch I found in a paper about constraint solvers.
I can draw the sketch and set some constraints, but I cannot add missing constraints without getting the "SOLVE FAILED!unsolvable constraints" message.
E.g. try to add perpendicular constraintes at the two straight line corners...
Even in the not fully constrained sketch I cannot move lines or some points.
Is there a problem with the sketch or do I hit the edge of solvespace's capabilities?
Attached the sketch.
tsk
(no subject) (by Daniel Engineering Solutions)
I took a look at your sketch and a couple things jumped out at me right off the bat. First, the scale of the thing is massive, which may be part of the issue. One way to work around this is to model the item at a smaller scale (it says the bottom line is over 1500 inches) and then import the sketch into another solvespace file where you scale it up to the proper size.
Another item I noticed was that the model isn't started from the origin. If that was done on purpose, then you may have hit the limits of the solver. I have found that keeping things as defined as possible (especially at large scale) helps modeling to go smoothly.
Another item I noticed was that the model isn't started from the origin. If that was done on purpose, then you may have hit the limits of the solver. I have found that keeping things as defined as possible (especially at large scale) helps modeling to go smoothly.
(no subject) (by ruevs)
Can you post a link to the paper?
(no subject) (by ruevs)
Otherwise yes - the line at the bottom of your sketch is 38294.6085178064mm long. The solver has known problems with big objects:
https://github.com/solvespace/solvespace/issues/1354
https://github.com/solvespace/solvespace/issues/1105
https://github.com/solvespace/solvespace/issues/246
Attached is a version where the length of the bottom line is 382.946085178mm and has no problems with constraints.
I made it with `CTRL-A`, `CTRL-C`, `CTRL-A`, Del, `CTRL-T` (Edit | Paste transformed...) with a `scale` of 0.01.
I'm still curious about the article and what the sketch was intended to look like when fully constrained.
https://github.com/solvespace/solvespace/issues/1354
https://github.com/solvespace/solvespace/issues/1105
https://github.com/solvespace/solvespace/issues/246
Attached is a version where the length of the bottom line is 382.946085178mm and has no problems with constraints.
I made it with `CTRL-A`, `CTRL-C`, `CTRL-A`, Del, `CTRL-T` (Edit | Paste transformed...) with a `scale` of 0.01.
I'm still curious about the article and what the sketch was intended to look like when fully constrained.
(no subject) (by ruevs)
Aha! Here it is:
https://acdl.mit.edu/ESP/Publications/AIAApaper2013-0702.pdf
https://acdl.mit.edu/ESP/Publications/AIAApaper2013-0702.pdf
(no subject) (by ruevs)
As a result of finding the article attached is a fully constrained according to "Figure 2" and "Table 2" sketch.
It required a few construction lines.
It required a few construction lines.
(no subject) (by ruevs)
OpenCSM an interesting vapourware
https://www.google.com/search?q=%22OpenCSM%22
or at least I do not see the "open" source.
https://www.google.com/search?q=%22OpenCSM%22
or at least I do not see the "open" source.
(no subject) (by ruevs)
(no subject) (by ruevs)
Re: simple sketch not able to be constrained (by tsk)
Hi ruevs,
Sorry for not answering earlier, I wasn't online.
Yes, that was the paper.
Thanks for your help.
Are you working on solvespace?
tsk
Sorry for not answering earlier, I wasn't online.
Yes, that was the paper.
Thanks for your help.
Are you working on solvespace?
tsk
Re: simple sketch not able to be constrained (by tsk)
Hi,
Just for the records:
This is the exact sketch like in the paper.
I needed three construction lines to accomplish that.
Would it be possible to add constraints that would allow to constrain the sketch without these construction lines?
Just for the records:
This is the exact sketch like in the paper.
I needed three construction lines to accomplish that.
Would it be possible to add constraints that would allow to constrain the sketch without these construction lines?
(no subject) (by ruevs)
> Are you working on solvespace?
A little bit :-) I do have commit privilege.
> Would it be possible to add constraints that would allow to constrain the sketch without these construction lines?
One construction line from your solution can be avoided - the one where the two arcs on the right are tangent. Just make the "radius" one go through the center of the bottom ark - see my solution above.
The other two construction lines are (currently) unavoidable.
It is possible to create a new type of constraint - "angle between line and arc" or "angle between line and curve" but since it is easily achieved with a tangent construction line it is probably not worth it.
A little bit :-) I do have commit privilege.
> Would it be possible to add constraints that would allow to constrain the sketch without these construction lines?
One construction line from your solution can be avoided - the one where the two arcs on the right are tangent. Just make the "radius" one go through the center of the bottom ark - see my solution above.
The other two construction lines are (currently) unavoidable.
It is possible to create a new type of constraint - "angle between line and arc" or "angle between line and curve" but since it is easily achieved with a tangent construction line it is probably not worth it.
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