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Unread 22-09-2013, 21:49
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Re: Modifying Vexpro Ball Shifter transmissions

I haven't asked Adam about his setup but from what he said I guessing they were running the 393s off the 6V output of the sidecar. The rules this past year allowed you to run the 393s off of a speed controller (R52 in the 2013 Robot Manual). We ran two 393s off a single talon (at about 10V) to be our frisbee flicker. We would stall them pretty regularly during testing and never fried anything. On occasion we would lose a tooth on the internal gears but we only had to replace two all year. I'm not sure how well they will hold up under stall conditions for shifting but you can definitely get more power out of them by running them at around 10V instead of the 6V supplied by the sidecar directly. Probably need to do some type of position control on them or just lower the voltage you use to stall them, it might worth considering.

There might even be a full VEX solution to translate the rotary motion to linear with a 393, a small 12 tooth vex gear and a piece of VEX rack gear.
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