Quote:
Originally Posted by Oblarg
That's not how it works. If the torque output is high enough to break static friction, the robot moves *and* the wheels slip.
You can get a robot and test this, if you like.
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It depends on what current load is required to break traction. Almost every robot can break traction at some current below stall, but wheel slip is negligible when accelerating from a full stop across a range of gear ratios. (It's probably instantaneously slipping, but not really for long enough to matter) If you're traction limited at, e.g., 60% of stall or ~70 amps per CIM (lots of faster single speeds), you'll really never slip in a pushing match that you're winning. If you're traction limited at 15% of stall or ~20 amps per CIM, you're probably burning out every time you gun the throttle. Most low gears in FRC seem to aim for traction limited at anywhere from 40 to 55 amps per CIM, and I just haven't observed slipping in pushing matches the robot handily wins. The load on the wheels is relieved to some extent when the load starts moving / slipping, and momentum helps too.
228's robot this year was 4 cim / 2 mini, geared to like 7.5 FPS low gear, and tread-cut Colson wheels. As long as the drive didn't ride up on the pushing target (grumble grumble), it would push things like AM wheel robots without the Colsons slipping noticeably. And that's traction limited at like, 35 amps per CIM? maybe 40? I can't remember off the top of my head, but less than I expected.