3D Sketch Helical Curve Axis constraints not updating?

[Hunteil]

I have 3D sketches with Helical Curves constrained to each other to help sectionize later constraints in an assembly. I've found some odd behaviors doing this however.

1. Helical Curves do not update automatically when parameters are changed.
   Workaround1: Move End of Part up and down. (bug?)
   Workaround2: Edit the Helical Curve for it to update. (bug?)
2. If you constrain from the center axis of the Helical Curve it doesn't update too? See below image.

As you can see, the helical curve itself updated, but the center axis which is innately apart of it didn't.

The 3 lines you see there are constrained to effectively ride the center axis & curve points when it becomes longer/shorter etc. I use these lines to define planes b/c this is a skeleton for something later.

I attached a file with the same problem to further show the scenario.

Is this a bug?

Can this be fixed?

Ps: Using Inventor 2022. Awaiting for approval to upgrade Vault etc.

[Hunteil]

Still having this problem. New Example image... Same problem though. I just figured the extra image may help.

 I will however say that it seems to be related to constraints not transferring correctly between sketches on this latest example. For instance, if I edit the helical curves and change the diameter for each, the lines will update without problems. But as soon as I edit the overall height (pitch) of the preceding helical curve, it'll throw the error.

[Hunteil]

@johnsonshiue , Do you think this thread's problem can be fixed by the solution you gave here too? https://forums.autodesk.com/t5/inventor-forum/dimension-reversing-direction-helical-curve-looking-fo...

[johnsonshiue]

Hi! Yes, I think it should work better with UCS. The issue here is that the constraining direction could flip due to various reason. UCS allows you to rotate the coordinate and UCS origin planes steadily.

Many thanks!

[Hunteil]

Update: I applied the UCS solution and the following happened.

 If you want to see the file, It's attached.

It'll solve if you delete the middle line. And all the other scenarios do as well. But I want this line b/c I use it to create a plane. This seems like a silly thing to break. And that's why I think it's a bug.

[Hunteil]

I figured out the problem... I just added another UCS at the mid point to get around it... But I want to report the actual constraining problem as as a bug or something to be solved b/c this is not intuitive and very clunky as it stands...

[johnsonshiue]

Hi! I believe this may have something to do with the parallel to Y axis constraint. This constraint applies to the origin Y, not the UCS Y. If I delete the constraint and add a colinear between the helical vertical curve and UCS Y, it will work better. Please take a look.

Many thanks!