gisnav-mock-gps-demo.mp4

Introduction

Warning Do not use this software for real drone flights. GISNav is untested and has only been demonstrated in a software-in-the-loop (SITL) simulation environment.

GISNav is a ROS 2 package that enables map-based visual navigation for airborne drones in a simulation environment.

GISNav provides a precise global position for an airborne drone by visually comparing frames from the drone's nadir-facing camera to a map of the drone's approximate global position retrieved from an underlying GIS system.

Mock GPS Example

The below steps demonstrate how GISNav enables GNSS-free flight with PX4 Autopilot's Mission mode in a SITL simulation.

You will need to have the docker compose plugin and NVIDIA Container Toolkit installed.

Build and run SITL simulation

Build the Docker images:

git clone https://github.com/hmakelin/gisnav.git
cd gisnav
docker compose build px4 qgc mapserver micro-ros-agent gisnav

Run GISNav along with supporting services:

docker compose up px4 qgc mapserver micro-ros-agent gisnav 

Note

• The build for the px4 and gisnav images may take a long time.
• The mapserver container needs to download roughly 1 GB of high-resolution aerial imagery when ran for the first time, so it may take some time until it starts serving the WMS endpoint.
• If the Gazebo and QGroundControl windows do not appear on your screen you may need to expose your xhost to your Docker containers (see e.g. ROS GUI Tutorial):

  for containerId in $(docker ps -f name=gisnav -q); do
    xhost +local:$(docker inspect --format='{{ .Config.Hostname }}' $containerId)
  done

Upload flight plan via QGroundControl

Once both the Gazebo and QGroundControl windows have appeared (QGroundControl should show the drone location near San Carlos airport), use QGroundControl to upload the sample ~/ksql_airport.plan flight plan that is included inside the Docker container, and then start the mission.

Simulate GPS failure

Wait until the drone has risen to its final mission altitude. You should see a visualization of the GISNav-estimated field of view projected on the ground appear. You can then try disabling GPS through your MAVLink Shell (accessible e.g. through QGroundControl > Analyze Tools > MAVLink Console):

failure gps off

The drone should now continue to complete its mission GNSS-free with GISNav substituting for GPS.

You can check if PX4 is receiving the mock GPS position estimates by typing the following in the MAVLink shell:

listener sensor_gps

If the printed GPS message has a satellites_used field value of 255, your PX4 is receiving the mock GPS node output as expected.

Documentation

See the latest developer documentation for information on how to setup a local environment for GISNav development, for code examples and API documentation, and for contribution guidelines.

License

This software is released under the MIT license. See the LICENSE.md file for more information.