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5.6.4.1 Off-route sensitivity and Recalculation delay
Depending on the quality of your GPS device, the GPS antenna location in the car
and the environment you are driving in, route recalculation can behave differently.
XROAD may think you have departed the proposed route and perform a
recalculation even if you have not done so.
When the GPS reception is poor (e.g. driving in an urban environment with a low
sensitivity GPS), occasional wandering (called position fluctuation) of the calculated
GPS position is likely. Although XROAD employs a sophisticated Lock-on-Road
system that will mostly suppress these position errors by aligning your position to the
recommended route and the road network of the map, sometimes the errors are too
large to correct.
To reduce the effect of large errors, you can increase the recalculation tolerance two
ways.
Off-route sensitivity
This is a range of relative values from 0 to 10, telling XROAD how far the GPS
position should be from the recommended route before the program decides to
recalculate. Lower values make XROAD insensitive to position errors; higher values
will result in quicker reactions.
Recalculation delay
This is a setting that helps suppress the effects of position fluctuation. With a few
seconds delay in recalculation even large position jumps can be survived without a
need for route recalculation.
5.6.4.2 U-turn penalty
You can fine-tune the way XROAD takes U-turns into account when planning a route.
You can tell XROAD how much extra distance you would travel to avoid a U-turn.
Note: This value is taken into account only if U-turns are enabled in Route
Parameters (Page 68).
5.6.4.3 Cross-border planning
By default XROAD plans routes using the border crossing points. However, if you
live near the border, you can disable border crossing with this switch to remain within
one country.
