[RyanCahoon]

Originally Posted by Jared

It's better because when it has articulated down, you get omni directional movement, and possibility for a higher gear ratio when traveling in both directions.

I think if I move the rotating set of omni wheels to the middle, it will work much better. When they rotate down, the robot will tilt, and the back omni wheels (facing forward) will come into contact with the ground.

I was playing with a similar drive idea a couple years ago (about the same time as the Iron Lions were doing their drive).

Here's an Inventor animation of the shifting action, and here's a VEX prototype of the drive. Even though it's more severe in the VEX prototype than it would probably have to be on a well-machined FRC bot, the biggest problem I saw with these designs is the amount of tilt necessary to get the traction wheels off of the ground, while still maintaining a decent wheel base in traction mode (these are competing interests).

The Iron Lions' design circumvented this by making the omni wheels part of the support in traction mode, but this means you can't get the dual gear ratios out of the switching system.

It might be interesting to look into utilizing 148's strafing wheel design from this year, where the strafing drive motors also do the actuation of the strafing wheels.