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Unread 22-06-2008, 12:26
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Re: BEI Gyro Accuracy

Quote:
Originally Posted by John Gutmann View Post
I found a way to compensate for the non linearity of the gyro but, the problem is that the gyro isn't consistent. I will turn it 90 degrees on way, then back to the starting position and it will read 0. But then when reset the system and try the same test it will be off by about 20 degrees. I then reset the system again, and its off by 5 degrees, and then without event reseting the system I turn it 90 degrees and it only changes the position by about 15 degrees, i turn it back to the starting position and it goes -90 degrees from where it was at.

I see absolutely no consistency in this device. It will work fine, but then when the controller is reset it will work totally difference.

I have scaling factors in to change the readings so they are equal from one direction to another, but that only solves the linearity problem.

I have figured there is something wrong with it this whole time simply because the neutral voltage is 2.1 volts. That just seems too far from the spec'ed 2.5 volts to be acceptable.

-John
I can't argue with your logic. It does sound like something is a little screwy with that gyro.
BTW, is there a chance you can share your scaling code to compensate for the non-linearity. For some reason, mine doesn't seem to work.
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