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Unread 06-12-2010, 23:11
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Re: Definitive FRC Mechanisms

Quote:
Originally Posted by AustinSchuh View Post
One concern with using the Jag in current mode was that we wouldn't be able to feed forward our drivetrain commands to the roller. (Backup tended to rip the ball out of the roller.) The solution to that ended up being to add the feed forward to the goal of the current loop.
I'm trying to parse the above. What I think I hear you saying is this:

Since backing up the robot tended to rip the ball out of the roller mechanism, you realized you needed more torque on the roller when backing up (and perhaps less torque when going forward?). So instead of using a constant setpoint for the current command, you subtracted some fraction of the drivetrain command from the roller current setpoint. Clever. Am I understanding it correctly ?