[ODE] Re: dynamic add of geom and mass to a body

Guillermo Andrade-Barroso guille.andrade at free.fr
Fri Sep 5 20:27:02 2003


> Martin C. Martin wrote:
> 
>>> See the boxstack demo for details.  I'm thinking of the compound object.
> 
> 
> The last time I checked, I'm pretty sure that the boxstack demo
> didn't actually do this right.
> 
> --Adam
> -- Adam D. Moss . ,,^^ adam@gimp.org http://www.foxbox.org/ co:3 "I am NOT a nut! I am the keeper of the seven universal truths!"


Exact! 

Take a compound object from boxstack demo, this object has a center of mass 
that coincides with its reference position and all initial geoms (and perhaps
some joints) are attached to this body. 

Now, you need to add another geom.In this case, the new geom changes mass,
inertia and center of mass of body. Because the implementation of ODE needs 
to preserve coincidence between center of mass and position of reference, you
need to change position of body and relative position of all geoms (and all 
joints) attached.

That justifies my preceding question.


Guillermo Andrade

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