Thread: Current Control
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Unread 12-06-2010, 02:37
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Current Control

Has anyone tried using Current Mode on the jaguars?
I tried it today in LabVIEW, but it did nothing. (I modified the voltage example to open the Jags in current mode, and replaced the "max voltage" stuff with controls for PID)
It's probably just an incorrect arbitration ID, but I was curious if anybody had already looked into it.

It seems to work with BDC-COMM, although I wonder if the integration was left out, or if the scaling is off. (Given constant load, constant setpoint, and constant nonzero P coefficient, there is a constant error.)
Also, the oscillation point is a little strange; oscilation becomes more apparent at lower speeds, but virtually disappears at higher speeds. I have trouble telling whether jerkiness of the motor is due to slow speed or to the oscillations of the motor. Can the Ziegler–Nichols method be used, or is there a different method? I suppose the inertia of the drivetrain or manipulator will help decrease the frequency of oscillation if I tune on a robot, not a test setup. Perhaps I should also attach a heatsink to the motor so it does not burn up. (At the moment I'm using a Fisher Price with a planetary gearbox)
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