Pioneer Avic-D3 Operation Manual page 138

accuracy.
To ensure maximum accuracy, the dead reckon-
ing system learns with comparing
the it estimates with your actual
as obtained GPS, it can correct for various
of error, such as tire wear and the rolling
motion of your vehicle. As you the dead
reckoning system gradually more data,
learns more, and the accuracy of its estimates
Iy increases. So, after you have driven
some distance, you can expect your position as
shown on the map to show errors.
D If you use chains on your wheels for winter
driving or put on the spare wheel, errors may
suddenly increase because of in
wheel diameter. The system detects the fact
that the tire diameter has changed, and auto-
matically the value for calcu
distance.
D If the ND-PG1 is used or if your vehicle is oper-
ating in hybrid mode, the distance cal-
culation value cannot be
automatically.
For maximum accuracy, your
continually compares GPS data with your esti-
mated position as calculated from the data of 3D
Hybrid Sensor. However, if on Iy the data from the
3D Hybrid Sensor is avai lable a
errors are
until the estimated position becomes unreliable.
For this reason, whenever GPS are avail-
are matched with the data of the 3D
and used to correct it for improved
How do GPS and dead reckon-
ing work together?
avai such as when your vehicle enters a
long tunnel, the d between your actual
and calculated may become
data comes from the
location of th is
circuit on your vehicle
model. In some cases, it is to
make a connection to it, and in such a case
we recommend that the ND-PG1 pulse
(sold be used.
's
on the
Sensor can even calculate
of and corrects for
des in the distance traveled caused by driving
winding roads or up slopes. the navi-
learns the driving conditions and
stores information in the memory. Thus, as you
drive more, the of the positioning
becomes more accurate.
3D hybrid mode
This is active when the speed pulse is detected.
Inclination of a street can be detected.
The method of position ing as follows
on whether the speed pu Ise of you r
vehicle is detected or not:
Simple hybrid mode
When the pu Ise is not position-
ing is performed in this mode. Only horizontal
movement is so it becomes less accu-
rate. when the positioning by GPS is not
Positioning by dead reckoning
The 3D in the
also calculates your The current loca-
tion is measured by driving distance
with the pu the turn direction with
the and inclination of the road with
the G sensor.
up from any open
surface.
The accuracy of the GPS information
how is. When the
strong and is GPS can determine
and altitude for accu rate
tion in three dimensions. But if
is poor, on Iy two latitude and
can be obtained and errors are
somewhat
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