SPAN Operation Chapter 3
SPAN-IGM User Manual Rev 2 29
INS Window: The Position, Velocity and Attitude (roll, pitch and azimuth) sections display data from
the INSPVA log along with standard deviations calculated from the INSCOV log. Information in the
ZUPT (Zero Velocity Update) section reflects the current INSZUPT command setting. The receiver
uses the X, Y and Z Offset fields to specify an offset from the IMU, for the output position and
velocity of the INS solution, as specified by the SETINSOFFSET command or the NovAtel Connect
SPAN wizard. The INS Configuration/Status section displays the IMU type, IMU Status and local
date/time information. The dial is a graphical display of the Roll, Pitch and Azimuth values indicated
by an arrow on each axis.
3.2 Real-Time Operation
SPAN operates through the OEM6 command and log interface. Commands and logs specifically related
to SPAN operation are documented in the SPAN on OEM6 Firmware Reference Manual (OM-20000144).
Real-time operation notes:
• Inertial data does not start until time is set and therefore the SPAN system does not function
unless a GNSS antenna is connected with a clear view of the sky.
• The inertial solution is computed separately from the GNSS solution. The GNSS solution is
available from the SPAN system through the GNSS-specific logs, even without SPAN running.
The integrated GNSS + INS solution is available through special INS logs documented in the
SPAN on OEM6 Firmware Reference Manual (OM-20000144).
• The IMU raw data is available at the maximum rate of output of the IMU (125 or 200 Hz).
Because of this high data rate, a shorter header format was created. These shorter header logs
are defined with an S (RAWIMUSXB rather than RAWIMUXB). We recommend using these logs
instead of the standard header logs to save throughput on the COM port.
Status of the inertial solution can be monitored using the inertial status field in the INS logs, see Table 4,
Inertial Solution Status on page 30.