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Unread 23-02-2012, 21:02
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Re: [FTC]: Servo has parkinsons???

Quote:
Originally Posted by PAR_WIG1350 View Post
We've had the same problem, might be an issue with the mechanism its attached to causing constructive harmonic interference (in other words, the servo corrects its position at the same frequency the mechanism sways/bounces/oscillates). If this is the case, mechanical dampers (such as a plate in contact with the mechanism to slow it down due to friction) might help.
This right here is generally the correct answer. The servos that you guys use in FTC are similar to that found on RC cars and planes. I have observed in both of these the "twitching" that you described. Every time I have been able to correct this simply by putting rubber washers in the mechanism and tightening it until the jitters stop. Any other form of stabilizing mechanism works too.

Before you do this, I will warn you that any kind of drag on the mechanism will cause inefficiencies. If you need the speed or the full strength of your servo to do the job, don't do this. Also, putting too much drag on the mechanism could cause the servo to overheat.

My recommendation: If the jitters in the servo don't affect anything, ignore them. There's likely nothing wrong with the servo and messing with an already working mechanism can screw things up.
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