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c#accelerometergyroscopemagnetometer

Which algorithm helps me offset sensor fused data?

I have this sensor fused data coming from a GYRO-ACC-MAG-hardware sensor.

It's data (YAW-PITCH-ROLL) goes from -180 to +180 or -90 to +90

Which algorithm helps me offset this to an arbitrary position and also have no sign change to minus?

What I mean is: -180 to +180 for instance leads to 0 to 359. And I want 0 not where 0 of the sensor is but also offset to a certain position. In other words, picture a circle. Now put a zero at an arbitrary position on that circle. Now rotate that circle around it's center point. The zero rotates along, so it is now at a different position than it was before, right? That's the idea.

What I did:

YAW + 180 leads to 0 to 359. Pitch + 90 leads to 0 to 179. Roll + 180 leads to 0 to 359.

Solution

  • If I understand you correctly, you want to make use of the modulo operator:

    double YAW360 =  (YAW+180)%360;

    See http://msdn.microsoft.com/en-us/library/0w4e0fzs.aspx

    The modulo operator makes a division and returns the division remainder:

    17 / 5 = 3 rest 2

    Therefore:

    17 % 5 = 2