aligning components fails

[picadilly]

Hi,

I am seeing a wierd behaviour when trying to align components.

The first five entries in the time line create to components with one body each. Then the body "BodyMoveable" is copyied and aligned to the body in "base". That works fine.

Then the component "moveable" is copied and aligned to component "base". The screenshot shows this with the alignment-tool still open. Looks fine so far.

Then you hit "OK". No entry in the timeline will be created.

Go back one step in the timeline. The component "moveable" disappears.

Forward one step in the timeline the component moveable reappears, but the alignment ist lost.

F3d-file is attached. This behaviour is occuring in way bigger design an causing me big pain. To make it more understandle, I created this simplified design.

[jeff_strater]

You have stumbled on one of the idiosyncrasies of Fusion:  Moving bodies and components in a parametric design are handled much differently.  After you move the "moveable" component, you say:

This is expected behavior.  Component moves (whether by dragging, Align, Drive Joint, Animate Model, etc) do not generate timeline entries.  This is considered a transient state, and in the upper right, you will see this UI:

This is telling you that the design is in a "component moved" state.  You can choose to Capture this position, or Revert it:

Choosing "Capture" will then put a Capture Position timeline entry in your timeline, which will be preserved.  If you do not Capture it, and you roll the timeline marker forward and back, the transient component position will be lost.

This is why most everyone on this forum will recommend not using Align or Move on components for important positioning actions.  Instead, use Joints to position one component relative to another.  A Joint is stable across geometry changes, where Align is not.  In your scenario, even if you had Captured that position, if you would subsequently change the height of the "base" component, your relative positioning of "moveable" would be lost - it would be in the same position, but no longer correct with respect to the geometry in "base"

[picadilly]

Jeff,

thanks for your timely response 🙂

I have to let sink in, what you wrote. Right now, lets say I am irritated.

I do need to look up and understand Joints. Somehow I did not warm up with them so far. Do you have a good example on hand? Otherwise I will find one.

Aside from that:

If you do the alignment as shown here, the alignment will show up in the timeline.

[jeff_strater]

I can't really tell what feature got added to your timeline, (because the red line covers part of it) but it looks like this is the Capture Position feature I mentioned.  Yes, it will appear, if you capture the position (either after the command, or by checking this box in the Align dialog):

here are 3 videos that illustrate:

1. Align Components, and Capture Position:

The next one illustrates Aligning bodies, which does add an actual Align feature to the timeline:

and, the third, which illustrates the difference between Align + Capture Position and Joint.  When I modify the first component after using Align, Component2 does not change its position.  This is because the Capture Position only records the relative position change of Component2.  However, if Joints are used (and they are pretty easy to use, IMO), the relationship is between the two geometries selected, and Component2 does update its position if Component1 is modified:

[picadilly · Accepted solution]

Hi Jeff,

I should have started using "Joints" 2 years ago. Would have saved me a few headaches. So, thanks a lot for explaining this to me 🙂

I also found out, where I got trapped:

In my initial post, second image, I wrote: "No entry in the timeline will be created." I did the alignment command in the activated context of the component "base". Any command is recorded in the timeline in context of the active component - well except the alignment of components (see next image).

If you change the context to the top level, magically the alignment appears in the timeline.

So, for what reason the alignment command will not be recorded in the time line in the context of the chosen component?!