Thread: Gyro problem
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Unread 05-02-2009, 09:06
EricVanWyk EricVanWyk is offline
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Re: Gyro problem

Quote:
Originally Posted by Coffeeism View Post
The gyro produces a voltage that will charge the capacitance in the wire. The longer the wire, the larger the capacitance, longer discharge time, longer change in voltage after gyro stops accelerating. It will also catch more noise if the wires are longer.
What you are describing is phase delay. Drift is where the null value (zero turn) drifts away from nominal, which is interpreted as a constant steady spin.

Your comment on phase delay is technically true, but not on a scale that is detectable. A cable that long will contribute a couple dozen picofarads. With a sampling frequency of 62,500Hz and an output impedence of 100 Ohms, you would need to add a couple hundred thousand picofarads to start to change things.

Since the gyro signal is only in the 0-200Hz(ish) range, I'd wager that phase delay will continue to be imperceptible.

However, the noise comment is very valid.