rtkbase

Documentation

Some bash scripts for a simple gnss base station

Installation:

• Connect your gnss receiver to raspberry pi/orange pi/.... with usb or uart, and check which com port it uses (ttyS1, ttyAMA0, something else...)

• Set your gnss receiver to output raw data. If you need to use U-center from another computer, you can use socat:

  $ sudo socat tcp-listen:128,reuseaddr /dev/ttyS1,b115200,raw,echo=0

  Change the ttyS1 and 115200 value if needed. Then you can use a network connection in U-center with the base station ip address and the port n°128.

• clone RTKlib

  $ cd ~
  $ git clone https://github.com/tomojitakasu/RTKLIB/tree/rtklib_2.4.3
  

• compile and install str2str:

  Edit the CTARGET line in makefile in RTKLIB/app/str2str/gcc

  $ cd RTKLIB/app/str2str/gcc
  $ nano makefile
  

  For an Orange Pi Zero SBC, i use:

  CTARGET = -mcpu=cortex-a7 -mfpu=neon-vfpv4 -funsafe-math-optimizations

  Then you can compile and install str2str:

  $ make
  $ sudo make install
  

• clone this repository:

  $ cd ~
  $ git clone https://github.com/Stefal/rtkbase.git
  

• Edit settings.conf:

  $ cd rtkbase
  $ nano settings.conf
  

  The main parameters you should edit are com_port, position, and the NTRIP section if you send the stream to a caster.

• If the U-blox gnss receiver is sets to its default settings (Raw output is disabled) you can permanently configure the receiver with ubxconfig.sh. For the ZED-F9P use

  $ ./ubxconfig.sh /dev/your_com_port receiver_cfg/U-Blox_ZED-F9P_rtkbase.txt
  

  This script will send the settings only if the firmware is the same release on the receiver and in the file. If your receiver use a more recent firmware, you can add the --force settings on the command line.

  $ ./ubxconfig.sh /dev/your_com_port receiver_cfg/U-Blox_ZED-F9P_rtkbase.txt --force
  

• Do a quick test with $ ./run_cast.sh in_serial out_tcp you should see some data like this:

  2019/10/09 15:42:53 [CW---]      14020 B   19776 bps (0) /dev/ttyS1 (1) waiting...
  2019/10/09 15:42:58 [CW---]      26244 B   19558 bps (0) /dev/ttyS1 (1) waiting...
  2019/10/09 15:43:03 [CW---]      37956 B   19289 bps (0) /dev/ttyS1 (1) waiting...
  2019/10/09 15:43:08 [CW---]      49684 B   19551 bps (0) /dev/ttyS1 (1) waiting...
  2019/10/09 15:43:13 [CW---]      61488 B   17232 bps (0) /dev/ttyS1 (1) waiting...
  2019/10/09 15:43:18 [CW---]      73076 B   17646 bps (0) /dev/ttyS1 (1) waiting...
  

  Stop the stream with

  $ sudo killall str2str
  

• If everything is ok, you can copy the unit files for systemd with this script:

  $ sudo ./copy_unit.sh
  

• Then you can enable these services to autostart during boot:

  $ sudo systemctl enable str2str_tcp.service <-- mandatory
  $ sudo systemctl enable str2str_file.service <-- log data locally
  $ sudo systemctl enable str2str_ntrip.service <-- send ntrip data to a caster

• You can start the services right now (ntrip and/or file), str2str_tcp.service will autostart as it is a dependency :

  $ sudo systemctl start str2str_file.service
$ sudo systemctl start str2str_file.service

• If you use str2str_file to log the data inside the base station, you may want to compress these data and delete the too old archives. For these 2 tasks, you can use archive_and_clean.sh. The default settings compress the previous day data and delete all archives older than 30 days. Edit your crontab with $ crontab -e and add these lines:

  SHELL=/bin/bash
  0 4 * * * /home/YOUR_USER_NAME/PATH_TO_RTKBASE/archive_and_clean.sh
  

  Cron will run this script everyday at 4H00.