Thread: Why you WANT to use a Gyro this year
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Unread 13-01-2010, 11:17
Jared Russell's Avatar
Jared Russell Jared Russell is offline
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Re: Why you WANT to use a Gyro this year
Take a look at the documentation for our kit accelerometer.

If set to +/- 2g operation, we're talking a resolution of 4mg (that's milli-g's) per LSB. The noise ceiling is spec'd at worst case +/- <1.5 LSB for the Z axis, <1 LSB for X and Y (at 100Hz data rate = 50Hz bandwidth).

In other words, at a 100Hz data rate, at roll of 5 degrees (0 degrees pitch), we would expect aX to read sin(5 degrees)*1g = 0.0872 g (or 87.2 mg). That's >20 LSBs - significantly above the expected noise margin.

In other words, I think you will find the accelerometer responds EXTREMELY quickly to angular changes. There's a reason they use accelerometers like ours on SUVs to detect roll conditions to deploy airbags.