SPAN Configuration

Minimum Recommended Configuration

When configuring your OEM7 SPAN system for first time use, the following is the minimum amount of information required to ensure proper operation of a SPAN system.

Required Information

Required Command

IMU type and communication port

CONNECTIMU

IMU to primary antenna lever arm

SETINSTRANSLATION ANT1

IMU to vehicle frame rotation

SETINSROTATION RBV

For optimal SPAN operation, the IMU to antenna lever arms and the IMU to vehicle frame rotation should be measured or calibrated to the best accuracy possible. Even small errors in the lever arm or RBV can lead to significant degradation of the overall INS performance.

While this is the minimum amount of information required, additional information is typically needed for SPAN systems. The following commands are commonly used to configure SPAN systems.

Common User Settings

Appropriate Command

Notes

IMU to secondary antenna lever arm

SETINSTRANSLATION ANT2

Only required for dual antenna systems

IMU to output position offset

SETINSTRANSLATION USER

Default output position is at the IMU center

IMU to output frame rotation

SETINSROTATION USER

Default output frame is the vehicle frame as defined by SETINSROTATION RBV input

Vehicle type

SETINSPROFILE

 

Minimum alignment velocity

SETALIGNMENTVEL

 

Configure SPAN Manually

Follow these steps to enable INS as part of the SPAN system using software commands:

A GNSS antenna with a clear view of the sky must be connected and tracking satellites for operation.

  1. Issue the CONNECTIMU command to specify the type of IMU being used and the receiver port connected to the IMU, see Table: Enable INS Commands and the CONNECTIMU command.

    Enable INS Commands

    IMU Type

    CONNECTIMU command

    HG1700 AG11

    CONNECTIMU COMx HG1700_AG11

    HG1700 AG17

    CONNECTIMU COMx HG1700_AG17

    HG1700 AG58

    CONNECTIMU COMx HG1700_AG58

    HG1700 AG62

    CONNECTIMU COMx HG1700_AG62

    IMU-CPT

    CONNECTIMU COMx KVH_COTS

    IMU-FSAS

    CONNECTIMU COMx IMAR_FSAS

    IMU-HG1900

    CONNECTIMU COMx HG1900_CA50

    IMU‑IGM-A1

    CONNECTIMU COMx ADIS16488

    IMU-IGM-S1

    CONNECTIMU COMx STIM300

    IMU-ISA-100C

    CONNECTIMU COMx ISA100C

    IMU-KVH1750

    CONNECTIMU COMx KVH_1750

    IMU-LN200
    IMU-LN200C

    CONNECTIMU COMx LN200

    IMU-P1750

    CONNECTIMU COMx KVH_1750

    IMU-µIMU-IC

    CONNECTIMU COMx LITEF_MICROIMU

    OEM-HG1900 (CA50)

    CONNECTIMU COMx HG1900_CA50

    OEM-HG1930 (CA50)

    CONNECTIMU COMx HG1930_CA50

    OEM‑IMU‑ADIS‑16488

    CONNECTIMU COMx ADIS164881

    CONNECTIMU SPI ADIS164882

    OEM-IMU-EG320N

    CONNECTIMU SPI EPSON_G320

    CONNECTIMU SPI EPSON_G320_200HZ

    OEM-IMU-EG370N

    CONNECTIMU SPI EPSON_G370

    OEM-IMU-HG4930 (AN01)

    CONNECTIMU COMx HG4930_AN01

    OEM-IMU-HG4930 (AN04)

    CONNECTIMU COMx HG4930_AN04

    CONNECTIMU COMx HG4930_AN04_400HZ

    OEM-IMU-ISA-100C

    CONNECTIMU COMx ISA100C

    OEM-IMU-STIM300

    CONNECTIMU COMx STIM3003

    CONNECTIMU COMx STIM300D4

    OEM-IMU-µIMU-IC

    CONNECTIMU COMx LITEF_MICROIMU5

    OEM-IMU-µIMU-UART

    CONNECTIMU COMx LITEF_MICROIMUD_400HZ6

    UIMU-HG1700-AG58

    CONNECTIMU COMx HG1700_AG58

    UIMU-HG1700-AG62

    CONNECTIMU COMx HG1700_AG62

    UIMU-LN200

    CONNECTIMU COMx LN200

    Use the COM port number the IMU is connected to.
    If you are using the OEM719+MIC board stack, you must use COM1.
    For SPAN systems with a OEM729 receiver, COM2 is the recommended serial port for the IMU, however you can use any available port for these IMUs.

  2. If the SPAN system uses an OEM-HG1900 IMU connected to a MIC card, issue the following command.

    SETIMUPORTPROTOCOL RS232

    Basic configuration of the SPAN system is now complete. The inertial filter starts after the GNSS solution is solved and the IMU is connected.

  3. Issue the SETINSTRANSLATION command, using the ANT1 parameter, to enter the distance from the IMU to the GNSS antenna. See the SETINSTRANSLATION command for more information.

    If the SPAN receiver has dual antenna inputs, issue the SETINSTRANSLATION command, using the ANT2 parameter, to enter the distance from the IMU to the secondary GNSS antenna.

    The offset between the antenna phase center and the IMU axis must remain constant and be known accurately (m). The X, Y and Z directions are clearly marked on the IMU enclosure. The SETINSTRANSLATION parameters are (where the standard deviation fields are optional and the distances are measured from the IMU to the antenna):

    ANT1 x_offset y_offset z_offset [x_stdev] [y_stdev] [z_stdev]

    This example shows a mounting configuration with a negative X offset, negative Y offset and positive Z offset.

    A typical RTK GNSS solution is accurate to a few centimetres. For the integrated GNSS+INS system to have this level of accuracy, the offset must be measured to within a centimetre. Any offset error between the two systems shows up directly in the output position. For example, a 10 cm error in recording this offset will result in at least a 10 cm error in the output.

    If it is impossible to measure the IMU to GNSS antenna offset precisely, the offset can be estimated by carrying out the Lever Arm Calibration Routine. See Lever Arm Calibration Routine.

    The Lever Arm Calibration routine is not available for the OEM-HG1930, OEM-IMU-ADIS-16488, OEM-IMU-EG320N, OEM-IMU-EG370N, OEM-IMU-HG4930, OEM-IMU-STIM300, IMU-CPT, IMU‑IGM-A1, IMU-IGM-S1, PwrPak7-E1, PwrPak7D-E1, PwrPak7-E2, PwrPak7D-E2, CPT7 or CPT7700.

  4. Issue the SETINSROTATION command, using the RBV parameter, to enter the Euler Angle rotation from the IMU Body frame to the Vehicle frame. See the SETINSROTATION command for more information.

    Accurate knowledge of the rotational offset between the IMU Body frame and the Vehicle frame (the RBV rotation) is critical to correctly computing an attitude solution, and is required before a Kinematic alignment is possible.

    The SETINSROTATION parameters are (where the standard deviation fields are optional):

    RBV x_rotation y_rotation z_rotation [x_stdev] [y_stddev] [z_stdev]

    The order of rotations is Z-X-Y. All rotations are right handed.

    For an example of how to solve for the IMU Body to Vehicle frame rotation refer to Rotational Offsets.

    If the rotation between the IMU Body frame and the Vehicle frame is not precisely known, enter an approximate rotation (to the nearest 45 degrees). The precise offset can be estimated by carrying out the Body to Vehicle Frame Rotation Calibration Routine.

SPAN Configuration with NovAtel Application Suite

NovAtel Application Suite provides a graphical user interface to help configure a SPAN system. For information about configuring SPAN using NovAtel Application Suite, refer to docs.novatel.com/Tools.

SPAN Configuration with NovAtel Manage Web

The SPAN parameters can be configured using the NovAtel Manage Web User Interface. For information about using Manage Web, refer to docs.novatel.com/Tools.