User guide

Racelogic Ltd DriftBox Tools
Software
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If you want to load a .cir file into DriftBox Tools on its own, click Load All and then type *.* in the
File name field:
You can then select the .cir file and it will load like a normal .dbn file.
A library of circuit overlay files is available from the DriftBox website. If you would like to share
circuit files you have created please contact us and they will be added to those already available.
Aligning Circuit Overlays and Laps
The standard positional accuracy of DriftBox is 5m 95% CEP for Longitude and Latitude.
CEP = circle error probable.
95% CEP means 95% of the time the position readings will be within a 5m diameter circle of the
true position. This error is due to the changing state of the ionosphere, constantly changing the
time taken for the satellite signals to reach the earth. This means that overlaid laps may appear to
miss the edges of the track, especially if the laps or overlay were logged several hours apart.
The Align Circuit Tracks feature allows post-processing analysis to counter some of this positional
error, by rearranging the driving lines or circuit overlay in the Graph:Map window. This can be
especially useful if the circuit overlay file has been created in Google Earth, which is not always
100% positionally accurate (a good example of this, at the time of going to press, is the Paul
Ricard circuit in the south of France – the Google Earth image is approximately 200m adrift of its
true position.)
This feature can also help to combat the effects of positional shift that have occurred between
sessions at a circuit, such as morning/afternoon or one day to another.