Deploy for development

The recommended way of developing GISNav is to deploy a SITL simulation and supporting services using Docker Compose while deploying the GISNav ROS 2 launch configuration directly on the host. With a local non-containerized installation of GISNav it is easier re-test the software without having to rebuild a Docker image and re-deploy a container every time changes are made to the source code.

Prerequisites

These instructions assume you have installed GISNav locally.

Deploy via Makefile Recommended

The easy way to deploy for development is via the Makefile. Use the below commands to run a local ROS 2 default launch configuration of GISNav and to deploy a supporting SITL simulation as Docker Compose services.

• The uorb target uses the micro-ros-agent middleware service.
• The ubx and nmea targets use socat to bridge the serial communication over TCP between the docker containers.

uORB Recommended for PX4

cd ~/colcon_ws/src/gisnav
make dev PROTOCOL=uorb

NMEA Recommended

cd ~/colcon_ws/src/gisnav
make dev PROTOCOL=nmea

u-blox

cd ~/colcon_ws/src/gisnav
make dev PROTOCOL=ubx

Todo

UBX support is not fully implemented and most likely does not work yet

Ctrl-C and relaunch

You can use Ctrl-C and then make dev again to kill and relaunch GISNav without killing the supporting services. This enables iterating with quick changes to the source code without having to restart the simulation. You will still have to colcon build --packages-select gisnav in your workspace after making changes to the GISNav source code before relaunching with make dev.

Deploy via ROS launch system

The Makefile uses the ROS launch system under the hood to define and deploy configurations of multiple nodes with preconfigured parameters and optional launch arguments.

Default configuration

A local.launch.py launch configuration is provided that allows choosing the output protocol and port.

To see what launch arguments the launch file accepts, type in the following command:

cd ~/colcon_ws
ros2 launch gisnav local.launch.py --show-args

Redirecting serial output for SITL simulation NMEA/u-blox

The px4 SITL simulation container listens for serial messages (NMEA or UBX) at TCP port 15000. GISNav NMEANode and UBXNode write into ROS, and the nmea and ubx middlware service use socat to bridge the serial communication over TCP between the docker containers. This TCP traffic is again directed to a serial port in the px4 container to make the mock GPS demo work in SITL simulation.

uORB bypasses the PX4 GPS driver

When using the uORB protocol, the PX4 GPS driver is bypassed and the uORB messages are used directly by the FCU.

The Makefile make dev PROTOCOL=nmea and make dev PROTOCOL=ubx recipes create a pseudo-tty (virtual serial port) using socat to bridge the GISNav serial port output via TCP to the Docker container running the SITL simulation. The Makefile hardcodes localhost as the container host as the targets are intended for local development, but you can use the below example if your simulation is running on a different host:

gnc start px4
PX4_IP=$(docker inspect -f '{{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' gisnav-px4-1)
socat pty,link=/tmp/gisnav-pty-link,raw,echo=0 tcp:$(PX4_IP):15000

Launch

You are now ready to launch GISNav via the ROS launch system.

uORB Recommended for PX4

cd ~/colcon_ws
ros2 launch gisnav local.launch.py protocol:=uorb

NMEA Recommended

cd ~/colcon_ws
PTY_PORT=$(readlink /tmp/gisnav-pty-link)
ros2 launch gisnav local.launch.py protocol:=nmea port:=${PTY_PORT} baudrate:=${BAUDRATE:-9600}

UBX

cd ~/colcon_ws
PTY_PORT=$(readlink /tmp/gisnav-pty-link)
ros2 launch gisnav local.launch.py protocol:=ubx port:=${PTY_PORT} baudrate:=${BAUDRATE:-9600}