SPAN Setup – InvenSense IAM-20680
It is only necessary to send the commands below if the IMU is changed or a FRESET command is sent.
To enable SPAN functionality for the InvenSense IAM-20680, issue the following commands:
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SETIMUEVENT IN EVENT1
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CONNECTIMU SPI INVENSENSE_IAM20680
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SETINSPROFILE LAND
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SETINSTRANSLATION ANT1 X Y Z [XSD] [YSD] [ZSD]
The values for X, Y and Z are the distances in metres along the X-axis, Y-axis and Z-axis, in the IMU Body frame, from the IMU center of navigation to the phase center of the primary antenna. The values for XSD, YSD and ZSD are the standard deviation values for the distances.
Large standard deviations can lead to an inaccurate position solution. Therefore, it is highly recommended to measure the translation offsets as accurately as possible and to enter translation offset standard deviations that reflect that accuracy.
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SETINSROTATION RBV X Y Z [XSD] [YSD] [ZSD]
The values for X, Y and Z are the rotations from the IMU body frame (indicated in Figure: InvenSense IAM-20680 Center of Navigation) to the vehicle frame. The order of rotations is Z, X, Y. All rotations are right handed. The values for XSD, YSD and ZSD are the standard deviation values for the rotations.
After completing the SPAN setup, an alignment of the SPAN system must be performed. Refer to System Start-Up and Alignment Techniques for details on System Alignment. A coarse alignment cannot be used with the OEM7500 Evaluation Kit IMUs.
