Gravimetric Corrections for the IMU

Although I’m still not entirely happy with my solution for the sensor fusion, I need to move on and if it creates a problem later on I’ll come back to it.

Just a note on the sensor fusion: I’ve discovered that it actually seems quite complicated to work out change in altitude from change in air pressure, and because I don’t really need this unless I have altitude hold, which I’m not going to implement for now, I’ve dropped any mention of pressure, temperature or altitude and am not using the barometer on board (for now at least).

This opens up possibilities of an open casing (or transparent) as the barometer is, as far as I know, the only light/wind-sensitive component, however I still plan to stick to a closed casing for the time being.
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More Sensor Fusion

Right, I’ve spent the last few hours condensing and altering Polulu’s AHRS System, which I have been planning to use for getting orientation data from my IMU board. As it came, it was just one large sketch (actually a group of 7 files, I think) that took the raw data from the board and turned it into Euler angles for orientation. I had to put it all into a class and alter the function names, etc. etc. so that I could use it as a library with my main Arduino sketch.

The long and short of it is, I’ve finally got it working as a library but on further testing I’ve noticed a significant drift in the sensor values.
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