[Gabe]

I looked at it for a long time and understood the explanation given to me pretty well (I think):

In planetary gearing the planet gears rotate inside the ring gear (which is the housing of the Banebots transmission); as long as the ring gear housing remains a fixed part of the drive relative to the motor shaft. Now imagine that the ring gear housing is allowed to freely rotate relative to the motor shaft. If the housing is turned against the rotation of the motor shaft, then the output speed of the transmission will decrease. If the ring gear housing is turned with the rotation of the motor shaft, then the output speed will increase.

I'll have to think a little more on why this is.


[Edit: The reason why is that as you rotate the ring gear the planet gears are being rotated faster on the internal gear, and they rotate in place if the sun gear counter-rotates. This means that the carrier plate will provide a lower output speed. Whn the ring gear housing is moving with the rotation of the input sun gear, then the planet gears rotate faster, which means that the carrier plate will also rotate faster.]