Hemisphere GPS V102 G, Руководство пользователя

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Chapter 3: Operation
Hemisphere GPS’ GPS Technical Reference describes the commands and
methodology required to recalibrate, query, or change the sensors status.
Tilt Aiding
The V102’s accelerometers (internal tilt sensors) are factory calibrated and
enabled by default. This constrains the RTK heading solution beyond the
volume associated with just a fixed antenna separation. This is because the
V102 knows the approximate inclination of the secondary antenna with
respect to the primary antenna. The search space defined by the tilt sensor
will be reduced to a horizontal ring on the sphere’s surface by reducing the
search volume. This considerably decreases startup and reacquisition times
(see Figure 3-2).
Figure 3-2: V102’s tilt aiding
Gyro Aiding
The V102’s internal gyro offers several benefits. It reduces the sensor volume
for an RTK solution. This shortens reacquisition times when a GPS heading
Table 3-1: Sensor operation summary
Feature Normal Operation Coasting (no GPS)
Heading GPS Gyro
Heave GPS None
Pitch GPS Inertial sensor
Roll Inertial sensor Inertial sensor
Tilt angle