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Full Version: Find center of gravity in LDCad or Studio
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I've searched around a bit for this question but haven't seen it asked.

I want to find the center of gravity of a model (horizontally, in two dimensions though the 3d center of gravity would be interesting).  Studio has its "stability check" feature which theoretically could answer the question (I could "balance" the model on a 1x1 brick and move that brick around until the model is deemed stable).  However after some testing, the stability check seems to behave unpredictably if there are submodels involved.  

I haven't made the leap to LDCad yet, but maybe it's time.  Is is possible to calculate center of gravity in LDCad?  Or is something similar to Studio's stability check (but hopefully better documented)?
(2019-10-24, 5:36)Hendrix Wrote: [ -> ]I've searched around a bit for this question but haven't seen it asked.

I want to find the center of gravity of a model (horizontally, in two dimensions though the 3d center of gravity would be interesting).  Studio has its "stability check" feature which theoretically could answer the question (I could "balance" the model on a 1x1 brick and move that brick around until the model is deemed stable).  However after some testing, the stability check seems to behave unpredictably if there are submodels involved.  

I haven't made the leap to LDCad yet, but maybe it's time.  Is is possible to calculate center of gravity in LDCad?  Or is something similar to Studio's stability check (but hopefully better documented)?
No solution I know of. One problem is that LDraw parts have no clear "interior", so deriving their volume and center of gravity of parts themselves is a non-trivial problem. I guess that Studio taps in Bricklink parts weight database, but that's not enough to give a precise answer.
Thanks for that.  Good to know that I'm probably searching for something that doesn't exist.  It's one of those things that seems like it should exist, but your explanation makes it clear why it probably doesn't. 

For my purposes, just treating the weight of the part as existing at its center point (or even origin) would be probably be precise enough.  I imagine this is what Studio does, but I can't seem to get it to behave predictably with submodels.  I guess I'm going to have to just build the thing for real and see.