pic: Swerve! (Module)

[NoodleKnight]

Isn't simplicity one of the key elements of this design?
It doesn't look like you can directly swap the chain/sprocket element with two gears, so you're going to at least need 3, which means you'll need to add in another shaft and its bearings to support it, which means more machining, on top of the gear/gear stock you have to buy and machine as well.

Anyways, shouldn't the encoders be measuring data off the wheel/the shaft that it's connected to? If so I don't see backlash being a problem, unless you're doing dead reckoning, which I'm sure our programming mentor has something to say against =P.
I'm not advocating to keep the backlash, though, if you can get rid of it then that's good.