GPS data is an integral part of navigation. If there are issues with the GPS, then that will interfere with the Navigation application. Three main scenarios can happen. The below sections define the results.
No GPS Device Connected At Startup
This section defines the case where the Avail system starts up, and no GPS data is being read from the serial port or the Avail application is misconfigured in some way. In this case, the GPS symbol on the status bar will be greyed out, the vehicle icon on the navigation application will be greyed out, and the navigation will also indicate there is no GPS signal.
There will be no navigation functionality until the GPS issue is resolved.
GPS Connection Lost During Runtime
This section defines the case where the Avail system starts up with GPS, but the GPS is disconnected during runtime. In this case, the GPS symbol on the status bar will be greyed out, the vehicle icon on the navigation application will be greyed out, and the navigation will also show gray bars indicating it is trying to recalibrate from the last GPS position.
There will be no navigation functionality until the GPS issue is resolved.
GPS Connection Valid But No GPS Fix
This section defines the case where the Avail system is receiving GPS data, but the GPS data indicates that there is not a valid fix. In this case, the GPS symbol on the status bar will be greyed out, but the Navigation application will not indicate that there is no fix for GPS.
In this case, the navigation may “drift” and show incorrect navigation information. The navigation application will return to normal function once the GPS fix is resolved.