Hi Tuan,
Kangaroo does not currently include any rigid body dynamics, so it is probably not an ideal way of approaching this problem.
It would be possible to make triangulated spring networks in the rough shapes of your parts and add collision between nodes and apply gravity or attraction forces, but it could get really heavy quickly if you have many parts.
Do you know RhinoNest ? It is a very powerful software for exactly this thing
Best
Daniel