This repository contains a ROS2 package to simulation an orbit movement for a drone.

The scripts are ran in the px4_simulator_container found in this gitlab repository here, which uses Ubuntu 20.04, ROS2 Galatic, Micro-XRCE Agent, PX4 and Gazebo.

The scripts were tested using software-in-the-loop (SITL). NED coordinate system is used in the code.

A video of the simulation demo can be found on YouTube here.

The drone will perform a clockwise orbit about the boat position, facing inwards towards the centre. It will start the orbit from the position (x+ORBIT_RADIUS, y). Boat positions are added to boat_queue and the drone goes to the boat at the start of the queue

cmd_timer_callback runs like a state machine to command the drone at different stages of the mission.

Start the px4 simulator container

cd px4_simulator_container
./launch_container.sh

Change directory into the ROS2 workspace

cd ~/ros_ws/src

Add SSH key to your github account. Follow instructions here.

View the generated public key.

cat ~/.ssh/id_ed25519.pub

Clone the repository

git clone [email protected]:yufanana/drone_orbit.git

Build with colon

colcon build

Alternatively, only build specific packages that were modified.

colcon build --packages-select <name-of-pkg>

Source the setup file

source /ros_ws/install/setup.bash

Start the px4 simulation container

cd px4_simulator_container
./launch_container.sh

Run tmux to have multiple terminals (tmux cheatsheet).

tmux

• The common shortcuts to use are
  • Ctrl + b % : split pane with horizontal layout
  • Ctrl + b " : split pane with vertical layout
  • Ctrl + b arrow key : switch pane to the direction

Source the setup file in each new terminal session

source /ros_ws/install/setup.bash

Run software-in-the-loop. This brings up Gazebo.

./start_sitl.sh

In 2 new terminals,

• run the offboard control node that commands the drone movements

ros2 run drone_orbit offboard_orbit

• run the boat publisher node to output the boat positions

ros2 run drone_orbit boat_publisher

In the terminal for the boat_publisher, enter dummy numerical values to introduce target positions for the drone to travel to.

Enter boat XY-position: <x> <y>