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Unread 09-02-2016, 17:59
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Re: Which servo? What's the difference between them?

This year, the biggest limitation is the practical one pointed out in the blue box below R29:
Quote:
For servos, note that the roboRIO is limited to a max current output of 2.2A on the 6V rail (12.4W of electrical input power). Teams should make sure that their total servo power usage remains below this limit at all times.
You should also look up the maximum current draw of each servo and manage this current limit.

Metal gears will likely be more robust in the case of collisions. Ball bearings will likely have less friction than bushings; in most problems with an answer of servo, this is not critical. You also want to consider speed - a high torque servo that takes 30 seconds to do a two second task isn't doing you any favors. (exaggerated, of course)

VRM: (emphasis mine)
Quote:
Originally Posted by R54
Servos must be connected only to the PWM ports on the roboRIO, either directly or through the PWM ports on a WCP Spartan Sensor Board. They must not be connected to the MXP, motor controllers, or relay modules.
If you're going to need 12W or more, absolutely. Make sure you include a hard stop in turn angle so you don't break your potentiometer.

If you have access to a mill, you can mill the spline pattern into the end of a short piece of hex shaft. However, If you're thinking of doing this, re-run the numbers, as these two systems are designed for different amounts of torque.
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