I'm trying to tune a Bayside motor and I'm having some problems. My setup:

[list]

[*]DMC-1740
[/*]
[*]Bayside rotary motor with worm drive (A screw is attached to the shaft of the motor. The threads of this screw engage a gear attached to my load.)
[/*]
[*]Using Bayside iDrive amplifier
[/*]
[*]Load has a long/heavy arm on one side. This may not be a big issue because when I replace this off-center load with an on-center load I still get the same behavior.
[/*]
[*]Dual Loop (encoder on motor and encoder on load)[/*][/list]

I've tried playing with the different tuning methods in WSDK. All of them work well for the short moves but the motion is very "jumpy" on the longer moves. However, when it stops, it nails the position (I get 0 counts of position error). Looking at a continuous plot of torque I see a sine wave. The best amplitude I've been able to get ranges from +6 to -6. The frequency of this torque sine wave appears to have a direct correllation with speed (i.e. the lower the speed, the lower the frequency).

I have tried adjusting the tuning parameters in Galil as well as in the Bayside iDrive amplifier but I can't seem to get smooth motion. I am more familiar tweaking Galil than the iDrive so more work has gone into tweaking Galil.

Can anyone help?

Thanks!