LORD 6254-4220, User Manual

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3DM
®
-GX5-15
User Manual
5.3.1 Bias Convergence
Accurate estimation of the biases can take several minutes to converge, therefore after the filter is
initialized, the free-inertial performance will continue to improve until the bias estimations settles.
The MEMS sensor manufacturers quote bias drift stability numbers which correspond to the
expected drift in bias while the sensor is operating. The filter attempts to track the changing biases
over time, and a user can expect these bias estimates will be non-constant during a navigation run.
5.4 Adaptive Anomaly Rejection
5.4.1 Gravity Adaptive
Enabling this feature allows the filter to stabilize attitude readings when undergoing linear
accelerations. The bandwidth setting determines the cutoff frequency of the filter applied to linear
acceleration changes ( see Communications Bandwidth on page 33 ). The high and low limits
determine the trigger points at which the stabilization is applied. The limit values are in
meters/second² and the bandwidth is in Hz. To find this setting, select the sensor name and then
Settings > Device > Estimation Filter > Gravity Adaptive.
Manual Adaptive (default setting): Enter user-set fixed values.
Auto-Adaptive: Automatically estimates the values internally.
Figure 23 - Gravity Adaptive Settings
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