[ODE] Controlling AMotors

[John Buehler]

How does one control an AMotor once it has been attached to a pair of bodies
connected through a ball joint?  I want to control the relative angles
between the two bodies by setting dParamLoStop and dParamHiStop pairs for
each axis.  Unfortunately, if I set those parameters to a pair of values
that is not inclusive of zero degrees, the joint flops around forever.  The
flop speed is dependent on how far away from zero degrees the hi/lo pair has
been set.  Further, constraining the lo/hi pair to zero does not restrict
the range of motion of the joint.

I've been clowning with this thing for a couple days and if anyone could
throw me a bone it would be appreciated.  The ODE examples just don't
provide any insights, and the documentation is a bit less than helpful.

JB