Hi
I am having problems accessing the coordinates of the base GPS.
My setup is using two um982 GPS (one on the copter and one on the ground). The two GPS-devices communicate through telemetry radios using baudrate 57600. The GPS on the copter is connected to a pixhawk 6C flight controller via GPS1.
When accessing the copter in QGC, I get fix mode: “3D RTK GPS Lock (fixed)”, which indicates, that the copter GPS receives the correction data correctly from the ground GPS.
What I would like to do, is to acquire the location of the ground GPS (MB base) on the copter through the flight controller.
When connecting directly to the GPS on the copter, I can see the location of the ground GPS (MB base) being sent to both usb (for debug)(COM3) and to the flight controller (COM1). It is sent with Unicore’s message AGRIC (find spec in https://globalgpssystems.com/wp-content/uploads/2021/08/Unicore-Reference-Commands-Manual-For-High-Precision-Products_V2_EN_R3.2.pdf). It does not seem like any other message descriped for the um982 contains the ground GPS’ location.
The copter GPS is set up with the following commands:
Factory reset + mode rover
• FRESET
• MODE ROVER
• GPGGA COM1 0.2
• GPRMC COM1 0.2
• AGRICA COM1 0.2
• UNIHEADINGA COM1 0.2
• config com1 230400
• saveconfig
Use UART2 (radio/telemetry link)
• config com2 57600
• saveconfig
get data on usb port (debug use)
• GPGGA COM3 1
• GPRMC COM3 1
• AGRICA COM3 1
• UNIHEADINGA COM3 1
• saveconfig
And the ground GPS is set up as follows:
Factory reset + mode MB base
• FRESET
• mode movingbase
• saveconfig
output correctiondata
• rtcm1006 com2 1
• rtcm1033 com2 1
• rtcm1074 com2 1
• rtcm1124 com2 1
• rtcm1084 com2 1
• rtcm1094 com2 1
• config com2 57600
• saveconfig
It seems like the mavlink message GPS_RTK (#127) should contain information about the location of the ground GPS (MB base), but this message does not appear in the Mavlink inspector of Mission planner/QGC.
Should anything specific be done in order for the GPS_RTK message to be sent from the flight controller? Or can the location of the ground GPS (MB base) be accessed any other way?
It is unfortunately not possible to simply connect the telemetry radio directly to the flight controller, since all other ports are in use.