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Rack & Pinions


New member
I'm trying to create an animation of two racks driven by a single
pinion. The racks run horizontally. One rack is above the
pinion the other below, and so they are moving in opposite directions.

I can animate this with no problem.

But here is the thing I can't figure out: The racks are two
different lengths. I want one rack to "fall off" the pinion and
stop and the 2nd rack to continue to be driven by the pinion.

How can I set up my animation to do this?

Right now, I can animate it so that the system stops when the end of
the short rack is reached, or vice versa, the short rack continues to
move (impossibly) until the lock rack reaches the end of its range of

Any ideas???


New member
hmmmm how about copying the servomotor on top of the existing motor. Inwhich case you will have two motors running at the same time. One controlling the shorter rack and the other Longer rack...

give it a try.