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Unread 09-04-2017, 03:28 AM
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pic: 2 Speed Swerve

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Unread 09-04-2017, 03:40 AM
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Re: pic: 2 Speed Swerve

Looks like it will work okay. Some of it seems a little sketchy though.
  • why ballshifting over dogshifting when you have to add another plate and another stage to make ballshifting work?
  • Even if you have to have ballshifting, the back of the ballshifting shaft is only supported by the ~1/4" shifting shaft that moves back and forth. Be like vex and use the more beefy 1/2" shoulder instead.
  • the red plates look a little too long to go without some type of support at the bottom. Consider using dead axle, or adding standoffs to the bottom, so it won't bend as much when it's hit from the side.
  • Do you have some kind of sensor for wheel direction and wheel speed?
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Unread 09-04-2017, 06:20 AM
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Re: pic: 2 Speed Swerve

This thing looks pretty beefy. What's the weight per module?

It looks like you could shave off a good amount of weight by making it a bevel-beside-wheel swerve. That would allow you to get rid of the overdriving 3rd stage gears after the shifter and the 5th stage gears beside the wheel. It would also shorten the module significantly, meaning you might be able to get away with live axle without adding standoffs (though it's still advisable). Something like this, except you wouldn't need the 3rd stage because your 2nd stage is already off to the side.
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Unread 09-10-2017, 12:37 PM
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Re: pic: 2 Speed Swerve

I'm a little confused by your reduction. A few things:

I wouldn't cantilever the ballshifter shaft like that. I would support the end of the shaft with a 1/2" bearing. You can't really support it by the shifter rod like that, and there's not much reason to cantilever the actual shifting stage.

You could make the entire module shorter by having the CIM drive one of the "pinions" for the shifter stage instead of driving a third gear, similar to how the COTS ball shifter gearboxes work. It would be one thing if you needed the extra reduction in order to reach your target speed, but you actually end up gearing the motor down, then up, then back down due to that overgear in the middle. If you just made that 1:1 you could probably get away with having the CIM drive one of the gears driving the ballshifter.

I would also make the output shaft of the swerve a dead axle. You already have a gear that can bolt onto a wheel, you might as well make that a dead axle so that you can get some free rigidity in your system.
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