[maclaren]

I agree that ball shifter is the only way to go. The big thing you will need to keep in mind is the spacing between the motors so that you can access the back of the output shaft; but I guess you could have the shift rod come out the end of the output shaft and shift it that way. if you use 3/8" face width gears place thin thurst bearings between the shifting gears then you should end up with an overall length of 1-1/4" ish plus the length of the body of the CIM.

As far as customizable ratios you would be limited as to which gear pairs you could use and still maintain the approriate center to center distance. The smaller the DP that you use the more ratios that you will have available to you; However the weaker the teeth will be.

Side thought: I have a really great idea of how to solve the problem with truning a swerve drive module. But I'm not going to say what it is until my team actually makes a crab drive system so I will just leave you guys in suspense. My idea would allow me to turn a four inch wide wheel EASIER yes easier than any standard crab drive module with any other size wheel.