Athena GET SL1, User Manual

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SL1 DATA LOGGER User Manual Rev. AD
sales.get@athena.eu www.getdata.it
ENGLISH
2 WHY ACQUIRE...
3 GPS SYSTEM
Data acquisition during test sessions is becoming increasingly important because it permits:
• Reducing the vehicle configuration time.
• Correcting driving errors.
• Controlling vehicle behaviour, statically and dynamically.
• Viewing all the acquired parameters.
• Controlling engine and chassis performance continuously.
• Viewing the lap times of a session once downloaded.
The GPS system (Global Positioning System), on which your GET system is based, uses an algorithm
in order to determine the position of the GPS module that receives the signal transmitted by the
satellites.
By measuring the time a radio signal needs to travel the distance between the satellite and the
receiver and by knowing the precise position of at least 4 satellites, it is possible to identify the 3D
position of the receiver.
24 GPS satellites in orbit, inclined 55 degrees with respect to the equator, are located between
18000 and 20000 km from the earth and rotate around it once every 12 hours.
The satellites transmit a signal between 1.2 and 1.5 GHZ (to prevent errors resulting from
atmospheric refraction) generated by a single oscillator (atomic clock).
The transmitted data contain information about the orbit of the satellites and the time of the
signal, which permit the receiver to define its position on the earth's surface.
The lap times are obtained via GPS: this solution eliminates the need to use
inconvenient beacons on the track and helps provide a time reference during data
analysis.
The GPS uses a stochastic algorithm and is strongly influenced by the quality of the
received signal.
In the case of magnetic or environmental interference, data quality is not
guaranteed.
There must be a minimum number of 5 received satellites to guarantee the quality
of the lap times.