Thread: Was ist das?????.....tiny CVT!!!!!!
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Unread 13-02-2004, 12:24
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Paul Copioli Paul Copioli is offline
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Re: Was ist das?????.....tiny CVT!!!!!!
Matt,

All very good questions. IF we ever use the CCT again, we will ask ourselves one very simple two part question: Can we transfer weight to our robot? If so, how much? If the answer to those questions are "yes" & >100 lbs, then the CCT is in for us.

Here's why:

Lately, FIRST games require a pretty fast move in autonomous to get to the objects first, then the game changes slightly (depending on the type of game). I am a big fan of changing gears, in general, if you can transfer weight to the robot. If no weight transfer is available, then I am on the fence (we are NOT shifting this year). The CCT gives a very simple and robust way to get instantaneous gear shifting without going into neutral and using pneumatics. It is true that a drive train with the same motors as the CCT will have a bit more useable power, but if you also need to shift, then the CCT is a simpler solution with about the same results. Besides, it is really cool to see your robot instantly (almost) triple its speed while it's driving (like a 'vette doing 40, then punching it).

As to the design in the picture. Our CCT used the same principle you are trying to achieve with your transmission, but when our testing revealed some limitations we switched to the worm gear on the ring gear motor. All I have to say is watch out for backdriving.

-Paul