How do I Create Group

[Anonymous]

Hi,

I have an assembly, and I would like to check the CG position of a group of objects inside the assembly (not the CG of the entire assembly, just some components considered together).

I see that by selecting several components and then by right clicking, I have the option "create group", which I think is the feature I need; unfortunately, as I click "create group" nothing happens.

Am I doing something wrong or it is actually a bug of the feature? Is there another way of calculating mass properties of a particular group of components?

Thanks

[James.Youmatz]

Hi @Anonymous,

I have to check to see if there is another way to do this, but I believe it has to do with how you create and nest your components. For instance let's say we have components A, B, C, D, E and they are all separate. As you noticed, we can right-click each individual component and select the Properties and get the mass properties for each component. But what if we want to see what the mass properties of A, C, and E, but not B or D. In this situation, I believe the way to do this would be to create a component that contains A, C, and E and then find the mass properties of this new component (as theoretically it is sort of a new component if we want to find mass properties of a group of objects). 

You also can hold CTRL and select multiple components and then right-click and select Properties. You then could create a selection set based off these selections as a quick shortcut to select these in the future. I do believe this should be the same result as the method above, although I have NOT checked the numbers to verify this. 

UPDATE: @neljoshua describes ^ perfectly in his post below! 

Thanks,

[neljoshua]

@Anonymous,

I struggled with this for awhile as well.  The key is knowing where Fusion creates the selection set.  When you select a group of bodies or components and create a selection set, the set appears at the top of the browser under "Selection Sets".  I suggest renaming the set so that it is obvious what it is.

Once you have done this, you can click on the set in the browser to select every entity in that set.

After doing that, right click on one of the entities in that group and select "Properties".  This will bring up a window that I believe shows the information you are seeking.

[neljoshua]

@James.Youmatz beat me to it!

I admit that neither have I verified the numbers.

[Anonymous]

Thanks for the advice, but I already tried to do in that way and the numbers are not correct. Actually, it gives you the mass properties of the first component you selected to define the selection set. It is the same that you obtain by holding ctrl, select several component and then right clicking to get the mass properties: for some reason it gives you the mass properties of the first component selected.

The only way I found to obtain what I need is by removing the components I don't want to consider, right clicking on the assembly name and then clicking on "properties"; after I get the informations I need, I simply press ctrl+z to go back and get again the component that I just removed. 

Anyway this is a really bad way to do that, because I need to modify the design of the component to get the CG where I want, and with ctrl+z I lose the modifications; also, Fusion is quite slow to remove and reload the components.

I hope you can suggest me I better way to do that.

Cheers

[neljoshua]

@Anonymous,

Huh.

You are right; it is the same as the first item in the set.  That does not seem correct (i.e., it is a bug).

This might be annoying, but perhaps you could select all of the bodies in question and then create a component out of them.  You could then look at the properties of that component.  The advantage of this is that you would only have one undo step after you got the information.  It is not a great solution, especially if you have already made everything into components.

@James.Youmatz, is this a bug, or is it as-designed?  If it is as-designed, I would humbly request that it be changed.

[James.Youmatz]

Hi all,

I need to do a little bit of research on this. Right now my train of thought is - I do not believe that the multiple select issue is a bug, but moreover a limitation (still need to verify that). My idea of nesting components however is one I want to investigate further. That "should" be the correct methodology, but if it is getting incorrect numbers, that is a bug! In any regards, I do agree that this is an area for improvement that I will try to push. I just want to explore this a little bit more before I jump to any conclusions!

Thanks,

[Noah_Katz]

Any progress on this?

I also often need to determine mass/CG of groups of components that may not be in the same subasy.