[EricH]

There are some comments I want to make here.

1) Many, many mecanum, swerve, and holonomic drives use chain. Don't ask how many chains a typical 118 swerve robot has; they rarely if ever throw one. I believe they use floating tensioners.

2) By eliminating the chains, you eliminate an easy place to adjust the gear ratio if you need to. This can be a factor on some "random" Thursday when you realize that the robot can't go over a field obstacle and needs to, or loses every pushing match, or isn't fast enough...

3) If you're always having trouble with chains, it probably means that you have them improperly tensioned or possibly there's a misalignment between sprockets. #25 chain is unforgiving but light; #35 is heavier but more forgiving, though even it has a limit. It's also possible that you may need to check your masterlink practices...

4) One big potential problem is that if the drive wheel on one side comes off the ground, that side is stuck. The easiest solution? Chains/belts/gears to another wheel on that side. (Mecanum and swerve can avoid this easily; omni may be able to if designed right.) Guess where that leaves you?

5) Other options: Gears (yes, gears--ask 25 and/or 703), belting (Gates is giving it out to FRC teams), and proper use of chain.

I'm not saying that direct drive is a problem--it isn't--but there are other options out there to play around with.