Momentary loss of GPS RTK and "PreArm: GPS 1: not health"


I have a setup on the quadcopter with dual RTK for position and heading using “simpleRTK2B Pro”, “simpleRTK2B lite” and “Pixhawk cube orange” with 4.2.3 ver.

The correction is external and passes throw “Mission Planner” to the cube and then to the Ardusimple boards.

I have encountered two issues:

  1. The “Mission Planner” is sending the message “PreArm: GPS 1: not health” in spite of the fact that both GPS are in “RTK Fixed” mode (see attached pic), why is that? and how can I fix that and clear the massage?

  2. during the flight, several times one or both of the GPS changes their status to FLOT of 3DGPS, it can happen momentarily or for 3-6 seconds, what is the problem?

I have attached the link to the flight log (the flight starts at 10:08:30), the Ardusimple board configuration, and the param file of the Pixhawk cube.

I would very much appreciate the help:)

It probably reports unhealthy if the refresh rate drops bellow 5Hz
Try reducing the number of constellations used.

thanks for the replay @amilcarlucas :slight_smile:
I will try your suggestion. Although from the log, I see that the delta for GPS0 (simpleRTK2B Pro-functioning as the moving base) is 0.2 milliseconds (5Hz) Hdop is almost all of the flight below 0.8.
I can say almost the same for GPS1 (simpleRTK2B lite- functioning as the rover) except at the start of the flight.
the “PreArm: GPS 1: not health” message is constant but the second phenomenon is mostly at takeoff, can it be related to the power problem?

Yes the delta should be bellow 200ms.

But I was talking about the GPS output rate. That is the one that matters for the EKF. And hence for the health

Where can I see the output rate? @amilcarlucas