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Unread 20-06-2008, 17:21
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Re: BEI Gyro Accuracy

Quote:
Originally Posted by John Gutmann View Post
What is the not moving voltage on your gyro end up being? (Your using a BEI right?) I know it is supposed to be 2.5, but mine is 2.1 volts. That just seems a littles too far off to just be a tolerance issue.

-John
Honestly, I don't know what my offset, or "bias", is for this gyro. But as I recall it is near 2.5vdc. In the code below, I do a 30 sample average of the gyro while it is stationary during initialization to determine what my "bias" is. 30 samples takes 3 seconds.


Code:
for(int i=0; i<=29;i++) // Collect 30 samples of Gyro output while stationary.
                          //The average will become the value for the BIAS.
{
  bias_acum += analogRead(GyroPin);
  delay(100);
}
  
gyroBias = (bias_acum/30);
The gyro I am using is a Analog Devices ADXRS150 equivalent. In fact the chip is a 22304, but the specs are the same as the 150. It came in the 2005 KOP.
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