Best Drivetrain

[JVN]

Originally Posted by Hachiban VIII

But if the playing field is flat, why bother with 6WD at all? I mean, two of the wheels aren't even touching the ground. So why bother? If the playing field is flat, save yourself some weight and only use 4WD with the wheel axels spaced 12" apart and casters on the front.

Two Words:
Normal Force.

If you want to build a robot capable of pushing, you want every ounce of weight sitting on top of the highest traction drive wheels you can find. If you have weight sitting on non-driven wheels (like casters) you are reducing the amount of normal force available.

In some games or for some strategies pushing is not an important consideration. In these cases a 6WD may not be important.

Brief Aside:
In my opinion drivetrain design is very formulaic. "If you want to do X then you need to do Y." It is all about the functionality requirements your team has, and the design trade-offs you are willing to make (these trade-offs may involve things like weight & team resources, or things like pushing power & top speed.)

I should write a paper on this sort of thing.

-John