Dual GPS output format for AOG

If roll is compensated before AOG gets the position set AOG antenna hight to 0.
The earth radius is the middle between those of the ellipsoid. As the virtual move is small, the miscalculation should be ok. When moving some km we should do better.
The two receivers are connected directly with the Ublox moving baseline feature. So the timing is the problem of them. I tried also calculations with GGA, the parser is in the MISC.ino. It didn’t work due to a bug in code in tan calculation (forgot to do radians) and now I didn’t test again.
Filtered roll and heading is necessary before calculation. When position changes in last digit at only 60 cm antenna distance roll/heading changes much.
Today I was driving and I reduced the filter, so it got much faster. Also the direction of virtual Antenna right was wrong.
On github now

Video of the test on YouTube

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Cracking progress,

This is the route id like to go with mine, seems like the most logical way forwards / best way to always get accurate heading. Look forward to giving the code a go.

@MTZ8302, I see you put your saved configuration files in the repo, which is nice. However is it possible to list which config options you had to set on the boards. I’m guessing you set the rates (to 5hz?), and enabled NAV_PVT messages on one of the units.

Also how is the second F9P getting data from the first? Is it over the same uart that the ESP32 is reading from, or is it using the other uart? I’ve looked over things but I’m not clear on this.

I connected Tx2 and Rx2 from one board to the other to get RTCM over.
First I set on both boards UART1 speed to 115200, UART2 speed to 460800 and activate NMEA+UBX+RTCM3 to inputs and UBX +RTCM3 to output on UART1+2. Then set Nav Rate to 100ms (10Hz).
In the messages I deactivated everything expect of (UBX) NavPVT on UART1 at one board and NavRelPosNED on UART1 at the other board. At both activate the RTCM messages 1077/1087/1097/1127/1230/4072.0/4072.1 on UART2.
Don’t forget to save the config!

The ESP32 is connected to both board UART1 separately (2x2 pins, RX/TX crossed (setup zone in code)). From one board you get UBX NavPVT and from the other UBX NavRelPosNED.

I added the UBlox PDFs to GitHub

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Hi,
I just bought simpleRTK2B+heading - Basic Starter Kit
Is it possible to connect it directly to the AOG? If yes how? Where can I find settings to read gps position?

Hi,

I also have the simpleRTK2B (big board) and the SimpleRTK2Blite (small board)
As far as i know it is not plug and play.
If you need precise heading and position, you can get the precise position of the small board (UBX-NAV-PVT) and the exact heading of the big board (UBX-NAV-RELPOSNED). The small board is the moving base, send correction data to the big board but needs to get RTCM from NTRIP at the same time.
So you need to connect both boards via USB to the PC.
The Power+GPS port is for the big board and the Power+XBEE is connected to the UART1 of the small RTK2Blite
I tried to modify AOG but until now it is not working properly.
I tried to implement the following features:

  • Connect both boards via USB and give the ubx data of both boards to a UBX parser inside AOG
  • Choose to which port you want to send the RTCM (Ntrip) data

Maybe someone else can give some hints to make it working.
My code is on Github

Thanks for Your reply.
Is it possible to disasemble it and reconfigure to use only one (big board) to have the position of tractor?
the second one can wait for better times.

Regards
Jacek

Yes of course.
They both can work independently.
You may need another configuration (Rover).

It’s to complex for me.
Yesterday I had tried and false.
What I did:
Both cards were connected together

  1. Got new firmware 1.12.
  2. Upgraded firmware with success.
  3. Tried to send new configuration files (rover version) - there was error. Lot of timeouts.
    Then I got small card off the big card.
  4. The device do not boot. u-center had no connection.
    Then small card went on big card.
  5. everything works with u-center, but not working on AOG.

What is the correct procedure?

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Try with different Baudrate inside u-center and be sure to select the right Com Port.
If connected through the Power+GPS Port it does not matter.
If connected through the Power+Xbee Port it needs to fit (for the new configuration 115200). Otherwise I am not sure (maybe 9600/38400).

20200310_230029_res I had it connected in such way.
I had only one port - COM5, Baudrate is 38400.

Connected like this you are connected to the small board. The baudrate needs to be correct. Try 9600/38400/115200.

Try the other USB Connector (for the big board), then the baudrate is not important.

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I’m trying on second board, but when I try to upgrade firmware I get timeout of u-center
image

Select baud rate 230400 in the update screen, no safeboot and no training as described above.

thanks, firmware upgraded.
What is the procedure to sent configuration file?
Only send file and restart the device? Or there is some magic to write the file to the device?

All written here.

Download from GitHub. Select the correct config. Transfer as M8 config file. Done.

should I store it to the flash?
image

Yes, otherwise the config is deleted after you unplugged the power.

I’d like to ask question once more to be sure 100%.
Should I use ublox M8/8 option? Not 9?