topic Re: Constraining a sketch element to a line segment or arc segment. in Fusion Support Forum

Constraining a sketch element to a line segment or arc segment.

cemejean — Wed, 21 Sep 2022 17:14:55 GMT

Is there a way to constrain the endpoint of a line, to just the segment of the line or arc that is drawn in the sketch? making it coincident does not constrain it enough for what I am looking for. A coincident will allow it to be anywhere along the 'infinite' length of the line, or the full 360 deg's of the arc. I would like to be be able to limit it to just the segment that is drawn in the sketch.

Re: Constraining a sketch element to a line segment or arc segment.

jeff_strater — Wed, 21 Sep 2022 17:32:59 GMT

no, there is no way to constrain a point to just the line segment. You can constraint it to a distance from the endpoints, but there no way that I know of to say: "keep this point coincident to the line, but within the start/end points of that line".

Re: Constraining a sketch element to a line segment or arc segment.

davebYYPCU — Wed, 21 Sep 2022 17:40:29 GMT

......

Re: Constraining a sketch element to a line segment or arc segment.

davebYYPCU — Wed, 21 Sep 2022 17:38:34 GMT

Which sketch?

The answer is yes. (Might take more than one Constraint)

Might help......

Re: Constraining a sketch element to a line segment or arc segment.

cemejean — Wed, 21 Sep 2022 18:06:50 GMT

If the dimension of the large circle is changed too drastically, the tangent line flips to the other side of the small circle. If I made the arc that the line is tangent to smaller, and the endpoint and/or tangent was restricted to that segment, then the line should not flip. I have been able to add an offset to another fixed line, and make the endpoint of the tangent line coincident to that offset line, and it seems to work. But I was looking for a 'simpler' way to do it.

Initial sketchDimeter changeAdded constraint

Re: Constraining a sketch element to a line segment or arc segment.

cemejean — Wed, 21 Sep 2022 18:16:54 GMT

However, this does not solve all the issues. If the angle of the line that the small arc is coincident to changes to rapidly, the circle can sometimes flip to the other side of that line.

Re: Constraining a sketch element to a line segment or arc segment.

davebYYPCU — Thu, 22 Sep 2022 00:19:52 GMT

Eventually I had to give in to the solver. Just one more constraint.

See if you can break it, I went from 10 to 300 with no drama.

Might help.....

Re: Constraining a sketch element to a line segment or arc segment.

cemejean — Thu, 22 Sep 2022 01:29:34 GMT

That looks like a step in the right direction, but still not a complete work around. The circle does not flip from side to side, but the tangent line still does (you did not include the tangent line in your sketch). I need the tangent line to remain in the correct orientation also.

Re: Constraining a sketch element to a line segment or arc segment.

cemejean — Thu, 22 Sep 2022 02:12:25 GMT

I went back and added the offset for the center vertical line and extended and constrained the tangent line to it. The constraint you added along with this one looks like it might work. I can go from 5 to 1000 and back, and it seems to be OK. I even went crazy with the numbers and went from 5 to 10000 with no issues. There is an issue with going back to 5 from such a high number. but going back to 10 works. For what I wanted, I do not expect to go above 200 or so.

Thanks for the help.

Re: Constraining a sketch element to a line segment or arc segment.

davebYYPCU — Thu, 22 Sep 2022 03:48:22 GMT

Did my sketch break with number/s you want to input?

I didn't need anything else but don't know what the sketch is for

I just tried adding the tangent line, still no problem.

Re: Constraining a sketch element to a line segment or arc segment.

cemejean — Thu, 22 Sep 2022 17:34:26 GMT

Your sketch did not break (the small circle did not flip sides). But I need the tangent line also. When I added the tangent line and ended it at the large circle, it still flipped when I changed the large circle radius to like 300. Once I added the offset vertical line and extended the tangent line to that, then the tangent line no longer flipped.

Re: Constraining a sketch element to a line segment or arc segment.

davebYYPCU — Thu, 22 Sep 2022 18:07:50 GMT

Edit the circular pattern add in the tangent line. Worked for me, but I did not have your data.

Might help....