Ground in Inserted component and Joints.

[LiveLover]

Hello! 
I'm trying use Join Origins base on Sketch geometry to align components.
Please look:
We have a.f3z with grounded component and Origin Joins constructed on different sketches in it:  Sketch in root component,  Sketch in subcomponent

And we insert a.f3z into b.f3z and make Join between Origin Joint from a.f3z and Origin Joint in b.f3z.
File has 3 Joints. You can unsuppress them one by one and see what heppens.

We get the strangest result if wee unsuppress first Joint

Component1 of the design "a" moves  relative to design "a" origin. But the component is grounded in a.f3z!!!
Does this Joint override Ground constraint? or there is no contradiction here... so please clarify what Ground do.

If you can explain other 2 joins behavior it would be cool.

Thank you for any your explanations.

[jhackney1972]

You need to attach your model(s), it is very difficult to discuss your issue from pictures and your description.

[jhackney1972]

One thing to always keep in mind is that if you have a subassembly, with any number of components below it, you must Ground one of the components of the assembly or subassembly to make it take effect.  Grounding a subassembly will not ground anything.

[LiveLover]

Hello John Hackney! Thank you for your replay!
Please help me understand this rule.
Lets consider this design. Component1 is subassembly. Component2 is a component in this subassembly.

If we ground any component we actually fix its local coordinate system position in Root component axis. For this component this is the only one effect.
After a component grounded his parent components are not movable via mouse dragging its bodies. And in addition to previous paragraph these are the all effects of component grounding.

Correct?

Oh yes I fixed this topic title "Not ground in subcomponent" but "Component grounded in Inserted design and Joints"

[jhackney1972]

You are partial correct.  In your simple example Component 1 is the subassembly so if you ground it, component one is grounded but component two is not.  If you ground component 2 only, the the entire subassembly is grounded.  In a more complicated subassembly structure which has assembly joints, this gets a bit more complex on how one component of the subassembly, if grounded, will affect other components in that subassembly and the top level.  The Screencast may help explain this.

[LiveLover]

John Hackney! Wow! thank you for your explanations!
It seems that in this design you prefer use subassemblyComponent only as a container for another components (it has no bodies itself).

But if we have a body in a subassembly we may see that it is not grounded.
Please look this.
https://autode.sk/3pnLeEF

And it must be as clarification to " If you ground component 2 only, the the entire subassembly is grounded."

Cool design! Is it published in some tutorial? Seems very useful.


How do you embed screencast in forum post? "Insert Video" does not recognize https://autode.sk/3pnLeEF neither  nor https://knowledge.autodesk.com/community/screencast/6f7c4a11-d075-44bc-927f-71f1207cf6e2
and command are not captured (

[jhackney1972]

I have inserted your Screencast.  I place a second Screencast below it showing you how I embed you Screencast in this post.

Now, I stand corrected, I did not notice that the subassembly, Component 1, only had a body and no other component.  This is very unusual and as you demonstrated grounding Component 1 does not prevent you aligning the body.  Grounding is not available for bodies and since it is the only thing in the subassembly, grounding component 1 will not ground the body.  I apologize for my oversight.

[jeff_strater · Accepted solution]

a couple of important points here:

1. as @jhackney1972 said, each component can be independently grounded.  Grounding a subassembly does not ground its children (unless you have created rigid joints in the subassembly itself to fix those components relative to the subassembly's origin, which some people like to do).
2. Ground does not come across in an Insert workflow.  If you have grounded a component in a subassembly, it is only grounded when that subassembly is being edited.  If you insert that design into another design, nothing will be grounded in the new top-level design.  You must re-apply ground in the top level.  Grounding is only effective in the design in which it is applied.

[LiveLover]

John Hackney Thank you for explaining this!

And I'm sorry, I did not attach design and missed your first message...

This is the design.

[LiveLover]

Hello Jeff Stater!
Thank you for your answer!

@jhackney1972, @jeff_strater your answers gave me an idea:
to achieve the behavior I wanted: components that are grounded in the design we import are always remain there relative position.
we can:
In component that we import somewhere
create a "dummy" body and make a rigid group with this body and all grounded components.
make dummy body invisible.

Will it work?

[jeff_strater]

Yes, that will work.  That is a technique that people use to create a rigid sub-assembly that can be inserted into another all as a single rigid unit.  But, you don't need the dummy body - you can make a joint just to the sub-assembly's origin.  See the screencast below: