KevinG's Autonomous zero-point turn Lawn Mower

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I have GPS Yaw working now but not installed fully on the mower yet. I am doing this with all RTCM3 external to the flight controller. My connections are similar to Yuri’s except that I have the receive line on UART2 (Which is labeled TX2 on the SimpleRTK2B!) on the moving base connected to an incoming RTCM3 stream from a dedicated telemetry radio from the fixed base GPS.

To do this I had to make a few changes in Ucenter. I think that a small change in Ardurover will eliminate that need.

Some things I discovered:

  1. When Ardurover configures the GPSes, it sets the baud rate for both UARTS on both GPSs to 460800. Note that the settings of SERIALx_BAUD for the GPS ports is ignored. In my case, I a splitting the transmit and receive on the moving base. I want the receive to come from my fixed base RTCM3. My device that was feeding it could not run at 460800. I changed it to 115200, which I believe is plenty fast for the RTCM3.

  2. As long as GPS_AUTO_CONFIG is set to 1, the flight controller seems to reset the settings int the GPSes continually. If you try to change the baud, for instance, in Ucenter, it goes right back to 460800. You can turn off GPS_AUTO_CONFIG and change the baud rate and it will hold.

  3. Ardurover does not configure the incoming protocol for UART2 on the moving base GPS or maybe it configures it to NONE. Anyway, for my setup to work, I needed this to be configured to RTCM3, which I was able to do in Ucenter.

So, I believe that if the following changes were made to Ardurover, the system would have the flexibility of being connected as Yuri has done using MAVLink injection for Fixed Base to Moving Base or as I am doing, direct connection of RTCM3 from a dedicated telemetry system from Fixed Base to Moving Base:

A. Set the CFG-UART2INPROT-RTCM3X parameter in both the Rover GPS (already done) and the Moving Base GPS to 1.

B. Create 2 new parameters in Ardurover that allow the user to specify the baud rate Ardurover will configure both GPSes’ UART2 ports to.

C. OPTIONAL: I would think it best to let the SERIALx_BAUD parameters still set the baud rate for the GPS ports and thus the baud rate that Ardurover sets the UART1 ports on the GPSes. Perhaps a comment for the parameter would strongly suggest a high baud rate such as 460800.

If A and B were done, I would not have had to make any changes in Ucenter.

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