[ODE] Universal Joint / Arm -> rotating about its own axis

[David Nicolier]

Hum...the problem is not that they are not always perfectly enforced, it
won't
really bother me in this case ;)  but that the legs are doing a 180 or 360
twist sometime... 
I tried changing the ERP, it doesn't change anything :(
My sim is running at 50fps, and I'm just moving my character around with
some
small forces, and time to time the legs (or arms) are turning around their
axis 
(I mean in a natural way [->they turn at a slow rate, 1/2 sec for a 180],
except
they shouldn't). 

Martin, I can send you a small video (<500K) demonstrating the issue if
you'd
like ?

David


> Well, ODE doesn't guarantee that joints are always perfectly enforced. 
> Just as a ball and socket can come apart for a little while, or two bodies
> can interpenetrate for a little while, so the two axes of the universal
> joint can become non-perpendicular for a little while.  This will be
> especially true if, e.g. the rag doll is lying on top of its arm.  Does
> changing the ERP affect the behaviour you're noticing?