[Jared Russell]

You have to be careful that you think about this in the right way. There have been all sorts of crazy drive trains in FIRST. Ball drives. All sorts of swerves. Active and passive suspensions (especially this year). Walking file cards. Ball differentials. CVTs. 2 speed (AM-style), 3 speed (DeWalt + 222 ball lock shifter), 4 speed transmissions (33). Brakes. Triwheels. Traction wheels, inflatable wheels, omni wheels, mecanum wheels, treads. Nonadrive. The list grows every year.

Some of the above have been used to great effect on certain robots. Others tend not to do as well. What's the difference?

The teams that succeed on the field don't generally seek to innovate their drive systems for innovation's sake - they instead analyze the game and what they want their robot to do well and use that analysis to drive their choice of drive system. In other words, before trying to think of off the wall ideas, think of what possible situations would cause the "tried and true" FIRST drive trains to fall short.

Steps? Driving on sand? The return of regolith? What if you decide you need holonomic/swerve-like agility with extreme pushing power (especially if you decide that your team isn't a good fit for swerve, either financially or because of fabrication resources)? How can you ensure that nobody can cause your robot to turn if you don't want it to?

(I'm speaking about drive systems you would actually want to use on a competition robot here. In the offseason, or for demo purposes, sure, anything goes. But the teams that succeed on the field more often than not have competition on their minds before they go and prototype.)