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Kalman filter for accelerometer and gyro data fusion

Posted: Sat Dec 01, 2012 10:21 pm
by Mantas
Hello MM,

I implemented Kalman filter for accelerometer and gyro data fusion to get precise pitch and roll angles. But for this Kalman filter need time delta between two measurements, so I use timer interrupt running at 187200 Hz to increment the count and then later calculate the delta time using formula:

Code: Select all

dt = INTT/INT_FREQ; /*where INTT is the incremented count in the interrupt service routine, INT_FREQ is 187200 and dt is the float variable for delta time */
INTT = 0;
The problem is that Flowcode ARM v5.3 is limited to 6 digit precision in floating point variables, and sometimes I get very small dt smaller than 6 digit precision as the SAM7 chip is running really fast.

So my question is: when is that magical update finally coming? :D

Best regards,
Mantas