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Unread 07-03-2014, 00:05
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wireties wireties is offline
Principal Engineer
AKA: Keith Buchanan
FRC #1296 (Full Metal Jackets)
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Re: Looking at the KOP Gyro

Quote:
Originally Posted by RufflesRidge View Post
I'm a bit confused on the calibration method you are using. The sensitivity and the bias are two different things. If the angle drifts up-wards, doesn't that indicate that the bias is too low? How does adjusting the sensitivity downwards resolve this? I feel like I must be missing something in how this works.
The 2.5V is from a precision source though it could change as read at the A2D because of A2D errors, cable length etc. But I don't think it matters because (as you pointed out) WPILib takes this out in the Gyro constructor.

I am attempting to find the bias of the sensitivity, not do a dynamic calibration of the sensitivity. If the sensitivity is not 0.007 (and it is unlikely to be exactly 0.007 per the datasheet), the output of GetAngle() and GetRate() drift (often a lot, even just sitting on the bench). This is not a dynamic calibration - I don't think that is required for the way we use the gyro in FRC.
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