Athena Evolution GET MD60LOG User Manual page 4

One of the parameters that characterise GPS modules is the update rate expressed in Hz (Hertz): with this
information the number of times per second that the device is able to detect terrestrial latitude and longitude
coordinates is indicated.
In other words a module with an update rate of 1 Hz will detect the position once per second, whilst one with
a frequency of 5 Hz will provide, in the same time frame, 5 different coordinates: this translates into a higher
precision for the acquired trajectories.
The MD60LOG chronometer is capable of reading the times and the interval times on the lap thanks to a
finish line distinguished by precise GPS coordinates.
The above mentioned lines must be set out so that they intersect the track (see figure below): when the
vehicle passes the line the instrument is in this manner able to perform a calculation of the time for the lap (in
the case that this has to do with the FL, that is the actual finish line of the track) or for intermediate times (in
the case that a SPLIT line is crossed).
FINISH LINE
As indicated above, the GPS module provides the position at regular intervals of time (update frequency),
not necessarily in correspondence to the finish line. It often occurs that the system receives the position in
the P1 point (before the finish line) and P2 (after the finish line). The time correction on the lap read comes
about automatically considering the interpolation between these two points.
The basic hypothesis on which the above-mentioned calculation is based is that the speed of the vehicle is
constant. Therefore, if the speed between points P1 and P2 is constant, two modules with different update
frequencies will obtain the same performance in the calculation of the lap time.
FINISH LINE
P1 POINT
P2 POINT
MD60LOG User Manual rev. 05
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