[Sticky] GPS Logger FAQ
Can you tell me which recording format the logger supports?
In what unit does the logger record?
On the internal SD card the logger records in the standard NMEA0183 format. See http://spectran-developer.net/ftp/doc/G ... 161117.pdf for details on Aaronia sensor extensions. If you need another format for GPS data you can use the free GPS-Babel software to convert it.
The PC application software supports CSV exports as well (which can be imported in Excel for example). Please note that many applications may have problems importing large CSV files.
What is the datarate of the logger?
The datarate of the GPS sensor is fixed at 1 Hz. The datarate of the other sensors (accelerometer, gyrometer, compass, barometer) can be configured with the application software between 1 and 35 Hz (exact datarate can vary slightly esp. if GPS signal is missing).
What is the runtime on battery?
Depending on datarate this is estimated between 4 and 8 hours.
Can the logger run indefinitely when connected to a PC?
The standard USB power supply of 0.5 Ampere is insufficient to maintain the battery charge of the logger, so it will turn off at some point. If the USB port provides a higher power output it is possible for the logger to run indefinitely, but of course the storage capacity of the SD card is limited.
How do I use the logger with my own software?
For data analysis, the easiest option is to simply import the recorded NMEA files on the SD-Card. Alternatively you can control the logger directly over USB using the D2XX API from FTDI with our protocol documentation: See http://spectran-developer.net/ftp/doc/G ... 161117.pdf
Note: Accessing the logger over a COM-port is currently not supported.
Can the logger track acceleration of my vehicle?
The logger records raw 3D-accelerometer data which can be used to calculate linear acceleration, however this is not directly supported by the software yet.
How accurate is the reported speed-data?
"Speed" and "Acceleration" (application only) are based on the differences of GPS positions, so depending on GPS signal quality and environment you should not rely on those values alone.
Where can I find some sample data of the GPS Logger?
How does the data look like in a computer graph?
This depends on the application you use, our software does output graphs at this time.
How can I change date/time of the GPS Logger?
There is no way to manually configure date+time.
The date and time are taken from the GPS signal (in UTC). If the signal is lost temporary then the GPS sensor will continue to update the time for a while, however if the logger is used with no GPS signal at all it will have no data/time.
Some things described in the programming guide do not work with my unit.
Some features in the programming guide were added with later firmware versions. Unfortunately it is no possibe to update the firmware over USB, so if you want an update please contact our support at @aaronia.de">firstname.lastname@example.org.
Is it possible to have the logger to start recording as soon as the power supply is connected (and skip the calibration that starts when the logger is powered on with the logger switch enabled)?
No, this is not possible.
Is the logger approved for use in aircraft?
The logger has not been tested in an airborne environment.
The elevation data seems to be way off.
The elevation data is taken directly from the GPS sensor, the accuracy depends therefore on the GPS signal quality. In indoor environments signal reflections can degrade the quality massively.
Is the accelerometer data absolute or relative to standard earth acceleration?
Accelerometer data is absolute.
How are the axes of the gyroscope aligned?
X-Axis: pointing the unit upwards results in positive X-values, pointing it downwards results in negative X-values
Y-Axis: rolling the unit clockwise results in positive Y-values, rolling it counter-clockwise results in negative Y-values
Z-Axis: turning the unit clockwise results in negative Z-values, turning it counter-clockwise results in positive Z-values
How should the compass be calibrated when the unit is mounted on a vehicle?
Unfortunately the compass is very sensitive to magnetic interference. Therefore you cannot get accurate data when using it on a vehicle.
Do you have any additional software libraries to be used with the logger for data analysis?
When I turn the logger on ('power' switch 'on') the power LED turns green but the GPS led stays dark.