[ODE] joint forces

[Russ Smith]

paul.geisler at web.de wrote:
> It would be nice to have funcions which can report forces which
> traverses between two connected bodies over a specific joint. I got
> this idea, cause i want to simulate groups of objects which can be
> checked for "force overload" inside their joints, so parts can "brake
> apart" on their demand. So you could test the joint forces, and if
> they exceed a defined "break limit", the joint gets deleted, and the
> body could break apart.

ODE explicitly calculates the forces required to keep the jointed
bodies together. these are the forces "felt at the joint", the forces
that are trying to pull the joint apart. it's on my TODO list to
provide an interface that exports these forces to the user (for exactly
the application you describe).

note that breakable joints can be implemented in other ways: for
example using a joint constraint with force limits. new constraints
would have to be added, but you could easily get a "sticky surface"
or "magnet" effect.

russ.

--
Russell Smith
http://www.q12.org