Quote:
Originally Posted by Chris is me
@JesseK: I was suggesting 1 CIM + 1 FP in each of the forward wheels and then just a CIM on the side wheel since strafing is secondary to forward motion for a slide drive (if it isn't secondary, you should probably be using a holonomic chassis). With a crab module in the center I would probably suggest 2 CIMs on that and 1 CIM + FP on the outsides (off the top of my head here, not based on math or anything)
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Many teams get away with 1 CIM per side for a 10fps (or less) drive train and do just fine. Calculating the motor load based upon robot weight and gearing inefficiency puts the motor efficiency within a nominal amount of its maximum efficiency while just driving. If sound judgment is used on the drive train with respect to turning (wheel base for traction, or use of omnis, 6WD drop-center, etc), almost the same results would apply. Thus, as long as the team doesn't try to push another traction robot they'll be ok.
Your initial instinct is correct for what many teams want -- 11+ fps.
Quote:
Originally Posted by AdamHeard
You'd also have to design carefully to ensure that when the module rotates, the module rotates relative to the floor, not the module stays in place and the robot rotates around it.
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Good point, I didn't even think about that... It'd almost have to be an omni wheel at that point in order to prevent this completely.
Quote:
Originally Posted by spiffyspleen
Thank you guys! It looks like doing the mecanum drive is going to be a lot easier than I originally thought  |
The first iteration of Mecanum is always easy! If you build your drive train in the off season, play around with some extra weight. Specifically, see the effects of pushing a robot when the contact point removes traction from the front (lifts your robot slightly), and see the effects of just driving when your c.g. is too close to one of the wheels. Some interesting behaviors come out.