pic: Vex Teaser: What's Art been up to lately?

[jgraber]

Originally Posted by artdutra04

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At the moment I am working on a much more complicated design that mechanically will calculate the difference between two input shafts. For example if both shafts were rotating CCW at the same RPM, the difference between the two would be zero. But if the two input shafts were moving at different speeds the output shaft would rotate in one direction (CW if shaft A is faster, and CCW is shaft B is faster) at a speed proportional to the difference of the two shafts.

Nice work on the worm gear. Now that it is a few months later, how did it go?
Were you able to make a "South Pointing Chariot"?
Was it to make your holonomic drive "driver centric"?
Links from here might give you some ideas on differentials.
http://en.wikipedia.org/wiki/South_Pointing_Chariot
I thought the screwdrive one has some promise due to no requirement for bevel or planetary gears. You might also consider just doing the integration computationally, based on optical wheel encoders on the drive wheels or drag wheels.