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Kangaroo is a Live Physics engine for interactive simulation, optimization and form-finding directly within Grasshopper.
Daniel Piker
Hi Djordje,
Provided your solid is of uniform density*, its volume centroid will be its center of mass.
Grasshopper already contains a component for finding this point (Surface>Analysis>Volume)
In Kangaroo you can then make use of the way you can treat a rigid body as though all its mass is concentrated at this point, and still have the laws of motion and Newtonian mechanics hold true.
For accurate simulation of the rotation of a rigid body though, you will still need to actually have some mass points distributed away from the center of your object, as Kangaroo does not** contain a method for concentrating angular momentum at a point.
*I guess if the structure has parts made of materials of different densities, you can find the centroids of each part and then use an appropriately weighted average to get the overall center of mass.
**yet! - I'm working on this though, as having orientations for each particle could open up many other interesting paths...
Aug 31, 2012