Military Drones Simulation

Simulation setup for multi-drone surveillance using ROS 2 and the Gazebo simulator.

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Workspace Structure Assumption

This project assumes the following ROS 2 workspace layout:

~/ros2_ws/
├── src/
│   └── Military_Drones/
├── build/
├── install/
└── log/

If you do not already have a workspace:

mkdir -p ~/ros2_ws/src
cd ~/ros2_ws
colcon build

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Included packages

• military_drones_description - URDF/SDF drone models and mesh files.

• military_drones_gazebo - Gazebo Sim plugins and world configurations.

• military_drones_application - Holds ros2 specific code and configurations.

• military_drones_bringup - Holds launch files and high level utilities.

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System Requirements

Component	Version
OS	Ubuntu 22.04 LTS
ROS 2	Humble Hawksbill
Gazebo	Harmonic (8.10.0)
Python	3.10.x

Using other versions may require modifications.

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Installation

1. Clone Repository (Inside src/)

cd ~/ros2_ws/src
git clone https://github.com/Manohara-Ai/Military_Drones

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2. Install ROS 2 Dependencies

All commands below must be run from the workspace root:

cd ~/ros2_ws
source /opt/ros/humble/setup.bash

Initialize rosdep (only once per system):

sudo rosdep init
rosdep update

Install dependencies:

rosdep install --from-paths src --ignore-src -r -i -y --rosdistro humble

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3. Install Build Tools

sudo apt update
sudo apt install -y python3-colcon-common-extensions

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4. Gazebo Harmonic Configuration

ROS 2 Humble does not default to Gazebo Harmonic.

Ensure Gazebo Harmonic is installed.

Export the version before building or launching:

export GZ_VERSION=harmonic

(Optional) Add to your ~/.bashrc:

echo "export GZ_VERSION=harmonic" >> ~/.bashrc

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Build Instructions

cd ~/ros2_ws
source /opt/ros/humble/setup.bash
colcon build

If build issues occur:

cd ~/ros2_ws
rm -rf build/ install/ log/
colcon build

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Source the Workspace

Every new terminal must run:

cd ~/ros2_ws
source /opt/ros/humble/setup.bash
source install/setup.bash

(Optional) Add to ~/.bashrc:

echo -e "source /opt/ros/humble/setup.bash\nsource ~/ros2_ws/install/setup.bash" >> ~/.bashrc

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Running the Simulation

Launch Gazebo Simulation

ros2 launch military_drones_bringup military_drones.launch.py

Launch with RVIZ

ros2 launch military_drones_bringup military_drones.launch.py rviz:=true

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Development Workflow

After modifying any package:

cd ~/ros2_ws
colcon build
source install/setup.bash

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Known Issue: Gazebo Hanging at "Requesting world names"

Gazebo may hang at:

Requesting world names

Possible causes:

• Stale build artifacts
• Plugin load timing issue
• Corrupted install space

Recommended fix:

cd ~/ros2_ws
rm -rf build/ install/ log/
colcon build
source install/setup.bash

Then relaunch the simulation.

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Contributing

1. Fork the repository
2. Create a feature branch:

   git checkout -b feature/AmazingFeature

3. Commit changes:

   git commit -m "Add AmazingFeature"

4. Push branch:

   git push origin feature/AmazingFeature

5. Open a Pull Request

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Authors

Developed by Manohara & Vibhashree.

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