Re: Decent Gyro chips?

Doc wrote:
Anyone know of any decent gyro chips in a hand-mountable package...e.g.
DIP, SMT DIPs. I'm trying to measure angles irrespective of
acceleration, so "rate gyros" and inclinometers won't cut it.
Thanks
-Doc

Huh?

You appear to want an absolute angle sensor -- but absolute angles don't exist, at least not in a universe governed by Einstein's Relativity.

Any gyro will drift. A 'position' gyro will read out an offset from it's frame, but it'll still drift. A rate gyro will read out a rate that you have to integrate, giving you more opportunities to decrease the drift performance, but all else being equal a rate gyro can be as good as a position gyro if you support it with the right signal processing electronics.

For that matter, rate gyros or any other gyros are built to be insensitive to acceleration, although they always are sensitive to it to some extent.

If you're going to succeed with applying a gyro you have to expect it to drift a bit, and have some scaling errors. You have to determine just how much drift and other errors you can stand, then see if you can find a gyro that fits your application.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

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