X-drive rpm

I have been researching this years game and have found an X drive would be good for skills. If I made an X drive would a 1:3 (making it 300 rpm) on a red motor be viable for this Season?

Depends on the size of your robot and how much it weighs. Looking at the “Dunkin” robot in the other thread, that would be a good base, it’s a tall robot at 18" but not that heavy.

300 rpm would definitely be way too fast for an x-drive. when you have an x-drive the speed of your chassis is multiplied by sqrt2, so about 1.41. This means a 200rpm 3.25 inch drive will have the same speed as a 220rpm 4 inch tank drive and a 200rpm 4 inch x-drive will be about as fast as a 280rpm x-drive. Any drive above 300rpm is pretty uncontrollable and you have to be a very good driver to be able to efficiently handle one.


Gearing up with lose a lot of pushing power. A 4” x drive is already 280rpm, I wouldn’t push it much more than that


What would 3.25 wheels be at? Is this going forward or strafing?

At full throttle it will zoom, giving them cross field capability. They can always write programming in that lets them cut the speed down for fine motor control.

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Its 1.41:1 speed when all four motors are at equal power - orthogonal motion in Forward/Reverse or R/L strafe. When moving purely in any of the 45 degree directions, only two motors are running, and the speed ratio is 1:1.

So, yes, x-drive is faster in orthogonal directions, and would be hard to control at 300rpm . Its just not a simple answer, because the speed advantage drops off as you approach any 45 degree drive vector.

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