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resources:eval:user-guides:inertial-mems:imu-overview [21 Jul 2021 01:23] – [Bias Error] Chas Frick | resources:eval:user-guides:inertial-mems:imu-overview [31 Aug 2021 21:58] – [Linear-g Rejection (Linear-g Sensitivity)] Chas Frick | ||
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This can be thought of as the sensor resolution in an "ideal case." It is also found as the minimum of the AVAR plot. | This can be thought of as the sensor resolution in an "ideal case." It is also found as the minimum of the AVAR plot. | ||
- | ====== | + | ====== |
- | Applies to gyroscopes. It is the " | + | Measured |
- | ====== | + | Applies to gyroscopes. It is the " |
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+ | For an example consider the ADIS16153, with datasheet here: [[adi> | ||
+ | {{ : | ||
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+ | Additional notes: [[http:// | ||
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+ | ====== Rate Random Walk (ARRW) ====== | ||
Applies to gyroscopes and is the "far out" (large Τ) on the Allan Variance (AVAR) curve. | Applies to gyroscopes and is the "far out" (large Τ) on the Allan Variance (AVAR) curve. | ||
This quantity represents long-term stability of the sensor measurement. | This quantity represents long-term stability of the sensor measurement. | ||
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Can be approximated with the formula: ND ≅ ARW/60* √2 | Can be approximated with the formula: ND ≅ ARW/60* √2 | ||
- | ====== Linear Acceleration Effect (Linear-g) ====== | ||
- | Measured in degrees/ | ||
====== Vibration Rectification Error (VRE) ====== | ====== Vibration Rectification Error (VRE) ====== | ||
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====== Cross-Axis Sensitivity ====== | ====== Cross-Axis Sensitivity ====== | ||
- | Unintended effect where rotation/ | + | Unintended effect where rotation/ |
+ | Can be calculated from axis to axis misalignment error for accels/ | ||
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+ | Example: For the ADIS16448, the accel axis to axis misalignment is 0.2 degrees. Therefore Cross-axis sensitivity accel is sin(0.2) = 0.197%. Gyro is sin(0.05) = 0.09%. Magnetometer: | ||
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+ | ====== Linear Acceleration Effect (Linear-g), Linear Acceleration Effect on Bias, Linear-g Rejection (Linear-g Sensitivity) ====== | ||
+ | Unintended effect where linear acceleration is detected as rotation. Measured in degrees/ | ||
- | ====== | + | ====== |
- | Unintended effect where linear acceleration is detected as rotation | + | * Information on Allan Variance for Gyros: http:// |