Ok I have been looking at hardware options, for a duel antenna but simpler openGPS hardware setup.
I have seen a number of options.
To do duel antenna for less when it comes to GNSS boards, part of the build
UM982 RTK UAV Flight Control Board Full-Frequency Directional
https://www.ardusimple.com/product/simplertk3b-compass/
Unicorecomm UM982, Reliable GNSS Module for Accurate Directional Positioning
https://gnss.store/en/110–unicore-um982
Even versions that are raspberry pi hats. So you can direct mount it to a pi, and run software and brain in one package. So the tablet (Android for value) is just running openGPS not the second software package. The pi runs that? Maybe? Or the pi runs the lot, the tablet is just a display and control interface.
I am sure there are far more options using this new chip.
As these come standard with duel antenna support this seems an opportunity to cut the cost of duel antenna systems.
While the one most familiar to this discourse is not as cheap as others it does still allow all the original connection boards which includes WiFi.
I am a novice, but would like a chat to those that have helped develop the hardware setup used, and is being recommended, to see if there are more streamlined ways to do more with less hardware.
Being able to directly link a raspberry pi, could have new ways to run openGPS
I notice links that can create Bluetooth so it’s simple to link to Android and IOS for the old type boards.
While a port for Android is happening it’s not done as far as I know, not that I am software literate.
But options are around to do the same things the 4.5 board does now in new ways.
Also for RTK base stations.
https://gnss.store/en/um982-gnss-modules/327-elt0217.html
With its Triple-axis Magnetometer - LIS3MDL built in it would be very stable.
The Teensy 4.1 I can see it’s a very versatile board, very fast to send and receive data, and with lots of I/O and can bus etc. what exactly is it handling and would the direct connected pi setup, replace that entirely or would it still be needed? If the pi is acting at the tablet and its direct talking to the gnss then is the teensy, irrelevant?
I assume with a duel gnss and duel antenna setup, then just the wheel angle sensor is left as input, and then output is needed for the steering motor. With the pi handling the WiFi or Bluetooth talking to the tablet, then power supply a very compact duel antenna system could be made? As long as the pi can talk to the board doing the motor steering.
This is just me throwing ideas at the wall see what sticks, if I am incorrect that’s fine, but anyone with the skills that can look at my suggestion and say if as a concept it’s good or bad.
This is just to get a discussion going, so those better at the hardware side can shoot it down if needed.
I have not totalled up the cost of a standard 4.5 board in duel antenna mode against these options fully but that depends on what is actually needed over what I think it may need.