OXTS Survey+ v3, Руководство пользователя

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Oxford Technical Solutions
Table 23. NAVconfig heading lock options
Normal This option assumes the heading of the vehicle does not change by more than 2° while
the vehicle is stationary. The heading accuracy recovers quickly when the vehicle
moves.
Very tight The option assumes the heading of the vehicle does not change by more than 0.3°
while the vehicle is stationary. The recovery is fast if the heading of the vehicle does
not change but will be slow if the vehicle turns before it moves. This option can
cause problems during the warm-up period if the vehicle remains stationary for a
long time and then drives suddenly.
Note: The heading of most vehicles
does
change if the steering wheel is turned while the vehicle is
stationary. Junctions and pulling out of parking spaces are common places where drivers turn the
steering wheel while not moving.
Garage mode
The Garage mode option is used to stabilise the ’s outputs when GNSS is not
available. For example, GNSS can be blocked when the vehicle returns to the garage to
have some modifications. Without Garage mode enabled, the may drift too far
and may not be able to recover.
When Garage mode is active, the applies a zero velocity update and assumes that
the vehicle is stationary. This keeps the roll, pitch and velocity within acceptable limits
while the has no GNSS. With heading lock also enabled, the can also
keep the heading accurate while stationary.
When using this option, try to keep the vehicle’s movement inside the garage to a
minimum and exit the garage through the same door the car entered.
Enable local coordinates
The can output the displacement from an origin in a local co-ordinate grid. To
use this option a “zero” location or origin must be chosen; the latitude, longitude and
altitude for the origin must be entered into the RT. If an RT-Base S is available, then
these will be shown on the LCD. A rotation can also be specified to rotate the xy
directions.
This option assumes the heading of the vehicle does not change by more than 0.5°
while the vehicle is stationary. The recovery is fast if the heading of the vehicle
does not change but will be slow if the vehicle turns before it moves.
Tight
Heading lock Description