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Unread 15-01-2012, 18:41
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Re: Gearing for mecanum

We used stock 12:1 banebots planetaries with CIMs and 8" AM Mecanums several years ago and were relatively pleased with their performance.

I don't remember having wheel slip aside from when one of the wheels was off the ground, and we did get in some pushing matches... so I can say that a 12:1 ratio does not exceed the ability of an AM mecanum to put torque to the ground.

Going to a slower, higher torque gearbox, like the 16:1 may have advantages in that a higher torque output can allow for greater acelleration and better low-speed handling.

But I think I'd stay away from the 8:1 ratio... that seems very "fast" to me. Although it is common to calculate for a a robot's top speed, if you watch the game closely teams spend very little time at top speed, and a lot of time maneuvering, acellerating and decellerating.

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Unread 15-01-2012, 18:43
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Re: Gearing for mecanum

Okay, that helps clear things up.

I think that in our case, we want to be traction-limited more than fast. Therefore, I'll let the team know that we need a 16.25:1 ratio.

Thank you.
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Unread 16-02-2012, 10:55
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Re: Gearing for mecanum

If you used 9:1 for 8" wheels, would you expect to see CIMs cut out at initial full acceleration? Not that I have any reason to ask :-)
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Unread 16-02-2012, 11:05
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Re: Gearing for mecanum

We've used 9:1 on Andymark 6" HD mecanum for several years and are very happy with the results... That is at least close to a 12:1 on 8" wheels.

I'm not sure I'd want 8:1 on 8" wheels!
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Unread 16-02-2012, 11:07
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Re: Gearing for mecanum

Last year we used the mecanum wheels directly out of AndyMark nanotube. The gearing on that was 12.75:1. We were pleased with the results.
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Unread 16-02-2012, 11:40
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Re: Gearing for mecanum

We use the AndyMark nano transmissions but swapped gears to get 10.67 for 6" wheels - it works great. We figured quickness was paramount for this years game since the hump and bridges won't allow for full court sprints.

HTH
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