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Unread 14-02-2004, 17:46
Dave Flowerday Dave Flowerday is offline
Software Engineer
VRC #0111 (Wildstang)
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Re: ADXRS150 gyro yaw rate sensor

Quote:
Originally Posted by Brian M.
Another issue is when the gyro is rotated at a maximum rate, the output of the gyro is only 4.89 V (1006 analog output).
Brian,
Check out page 3 of the datasheet - it says that the gyro will only output 0.25v - (Vin - 0.25)v, so this isn't surprising at all. Actually, I'm surprised you're getting up to 4.89. Is your +5v actually higher than 5?

As for the problem with the middle value not always being 512, what we did with the gyro last year was to take a fixed number of readings from the gyro when the RC was first powered on and average them - in our case we read it 256 times, added them all up, and divided by 256. Additionally, you may want to wait a second or two after the RC is first powered up before taking these readings from the gyro, as the gyros usually take a moment to stabilize after they've been powered up. Obviously doing this means that your robot shouldn't be moved immediately after power-up.