PNI TCM - Manual (Page 34)

PNI Sensor Corporation DOC#1014688 r06
TCM User Manual – July 2013 Page 29
6.4.2 Calibration Results
Once a calibration is complete, the “Calibration Results” window will indicate the quality
of the calibration. This may take a minute or more to populate. The primary purpose of
these scores is to confirm the calibration was successful, as indicated by a low Mag
and/or Accel CalScore. The other scores provide information that may assist in
improving the CalScore, should it be unacceptably high. If either CalScore is too high,
click the button to begin a new calibration. If the calibration is acceptable, click
the button to save the calibration to the module’s flash. If the button is
not selected then the module will need to be recalibrated after a power cycle.
Note: If a calibration is aborted, all the score’s will read “179.80”, and the calibration coefficients
will not be changed. (Clicking the button will not change the calibration coefficients.)
Mag CalScore
Represents the over-riding indicator of the quality of the magnetometer calibration.
Acceptable scores will be <1 for Full-Range Calibration, <2 for other methods. Note
that it is possible to get acceptable scores for Dist Error and Tilt Error and still have a
rather high Mag CalScore value. The most likely reason for this is the TCM is close
to a source of local magnetic distortion that is not fixed with respect to the module.
Dist Error
Indicates the quality of the sample point distribution, primarily looking for an even
yaw distribution. Significant clumping or a lack of sample points in a particular
section can result in a poor score. The score should be <1 and close to 0.
Tilt Error
Indicates the contribution to the Mag CalScore caused by tilt or lack thereof, and
takes into account the calibration method. The score should be <1 and close to 0.
Tilt Range
This reports the larger of either half the full pitch range or half the full roll range of
sample points. For example, if the module is pitched +10° to -20º, and rolled +25º to
-15º, the Tilt Range value would be 20º, as derived half the full roll range. For Full-
Range Calibration and Hard-Iron-Only Calibration, this should be ≥45°. For 2D
Calibration, this ideally should be ≈2°. For Limited Tilt Range Calibration the value
should be as large a possible given the user’s constraints.
Accel CalScore
Represents the over-riding indicator of the quality of the accelerometer calibration.
Acceptable scores will be <1.