Amphibious Rover


I am planning to build an amphibious rover with two Pixhawks. One for rover, one for boat mode.
My question is, is there a way to share a GPS between the two FCs?
I guess, I could connect the GPS TX line to both Pixhawks and the RX line to only one, disabling GPS auto config on the other one.
A cleaner way would be to share the GPS via telemetry/Mavlink, but I do not know if/how this would work. Is this possible?

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@count74, I think doing what you’ve suggested (connecting the GPS’s TX line to both FCs) should work. Looking forward to the video :-)!

I am on vacation right now, so it can take a while, before I post a video. I am just planning what to build.

The amphibious rover is nearly finished.
The hull is made from 3mm plywood. The shape and track layout is loosly based on a russian PTS-M, but it is still missing the cabin/cockpit.
It is controlled by two Pixhawks. They are connected through telemetry 2, so only one needs a USB/telemetry connection. GPS is connected to both Pixhawks via Y-Cable in the GPS TX line.
Only one Pixhawk has a power module ( the one controlling boat mode) for now, because the other power module I had spare, decided to release its magic smoke.
It is powered by 4 4000mAh 2s Lipos, connected as a 8000mAh 4s pack. On land it is driving on tracks. I used three cheap robot chassis from amazon to get the parts. The brushed gear motors are a little weak for the 5kg rover, but I am going to replace them soon.
On water, two brushless outrunners drive two shortened 3 bladed racecopter props.
Here are a few pictures, the video is still uploading:


How do you select the right motors for earth and water?

The rover has two pixhawks, both connected two one receiver via sbus. The tracks are controlled by one pixhawk, the props by the other.
One pixhawk has ch5 set as flightmode channel, the other channel 8. I programmed a second 6 position switch mixer in my Taranis. Now I can independently select flightmodes for both pixhawks. The one I do not need is in “Hold” mode. Or I activate both for transitioning in and out of the water. This is also useful in the small creek near our house, to get over obstacles. I still have to try, how and if all this works during auto missions…