Navigation Mode; Data Collection; Table 12: Solution Parameters - Novatel SMART7 Installation And Operation Manual

SMART7 with SPAN Operation

4.5.3 Navigation Mode

Once the alignment routine has successfully completed, SPAN enters navigation mode.
SPAN computes the solution by accumulating velocity and rotation increments from the IMU to
generate position, velocity and attitude. SPAN models system errors by using a filter. The GNSS
solution, phase observations and automatic zero velocity updates (ZUPTs) provide updates to
the filter. Peripheral updates can also be supplied; wheel sensor for displacement updates or an
external receiver for heading updates.
Following the alignment, the attitude is coarsely defined, especially in heading. Vehicle dynam-
ics, specifically turns, stops and starts, allow the system to observe the heading error and
allows the heading accuracy to converge. The amount of dynamics required for filter con-
vergence vary by the alignment quality, IMU quality, and maneuvers performed. The INS Status
field changes to INS_SOLUTION_GOOD once convergence is complete. If the filter decreases in
its system accuracy, the INS Status field changes to INS_HIGH_VARIANCE. When the accuracy
converges again, the INS status continues as INS_SOLUTION_GOOD.

4.5.4 Data Collection

The INS solution is available in the INS-specific logs with either a standard or short header.
Other parameters are available in the logs shown in Table 12: Solution Parameters below:
Parameter
Position
Velocity
Attitude
Solution Uncertainty
The INSATTX log, INSPOSX log, INSPVAX log and INSVELX log contain solution and
variance information and are therefore large logs. Use a low logging rate (<20 Hz) only.
These logs also contain solution uncertainty in standard deviation format.
Note that the position, velocity and attitude are available together in the INSPVA log, INSPVAS
log and INSPVAX log.
The inertial solution is available up to a rate of 200 Hz. Data can be requested at a specific syn-
chronous time interval, asynchronously matching the IMU output rate, or can be triggered by the
mark input trigger at rates up to 200 Hz.
SMART7 Installation and Operation User Manual 0C

Table 12: Solution Parameters

INSPOS or INSPOSS
INSPVA or INSPVAS
INSVEL or INSVELS
INSSPD or INSSPDS
INSPVA or INSPVAS
INSATT or INSATTS
INSPVA or INSPVAS
INSSTDEV or INSSTDEVS
Logs
INSPOSX or INSPVAX
INSVELX or INSPVAX
INSATTX or INSPVAX
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