Manipulator Drone

A ROS 2 package that integrates PX4 SITL, Gazebo Harmonic, and ros2_control for simulating and controlling a manipulator-equipped drone.

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🚀 Overview

This package provides:

• PX4 + Gazebo SITL integration.
• ros2_control interface for actuators.
• Support for custom URDF/Xacro and SDF models.

The goal is to simulate and control a quadrotor drone with an attached manipulator arm using ROS 2 and Gazebo.

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📦 Requirements

• ROS 2 Humble
• Gazebo Harmonic (source install)
• PX4 Autopilot
• ros2_control
• gz_ros2_control

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⚙️ Installation

1. Clone PX4 and setup SITL with ROS 2:

   git clone https://github.com/PX4/PX4-Autopilot.git --recursive
   cd PX4-Autopilot
   make px4_sitl gz_x500

2. Install ROS 2 Humble (desktop version recommended).

3. Source install Gazebo Harmonic:

   git clone https://github.com/gazebosim/gz-sim -b harmonic
   colcon build --merge-install

4. Install gz_ros2_control:

   git clone https://github.com/ros-controls/gz_ros2_control.git
   colcon build --merge-install

5. Export required environment variables:

   export GZ_SIM_RESOURCE_PATH=$HOME/iiit_ws/install/darm/share/darm/models:$GZ_SIM_RESOURCE_PATH
   export GZ_SIM_SYSTEM_PLUGIN_PATH=$HOME/gz_ros2_control_ws/install/gz_ros2_control/lib:$GZ_SIM_SYSTEM_PLUGIN_PATH

6. Build this package:

   colcon build --packages-select darm
   source install/setup.bash

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▶️ Usage

To launch the simulation.

#inside PX4-Autopilot:
prime-run make px4_sitl gz_x500 

#launch qgc

#inside arm workspace
prime-run ros2 launch darm trial.launch.py 

#inside a serperate terminal 
ros2 run darm thrust

#launch xrce dds agent in a seperate terminal
MicroXRCEAgent udp4 -p 8888

#finally publish commands to the arm topics once everything is initialised
ros2 topic pub /{insert controller name here}_effort_controller/commands std_msgs/msg/Float64MultiArray "{data: [0]}"

This will:

• Spawn the x500_base drone model with manipulator.
• Launch ros2_control with the configured controllers.

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🛠 Troubleshooting

Check the Error.md file for common issues and their fixes.

Example:

Error	Fix	Reason
The supplied world name [world] is reserved	Rename world in SDF	world is a reserved keyword in Gazebo
Could not load resource ... Unable to open file	Ensure meshes are installed under share/darm/urdf/...	Symlink issues during build
Failed to load system plugin [gz_ros2_control-system]	Export GZ_SIM_SYSTEM_PLUGIN_PATH	Plugin library path not found

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📚 Resources

• ROS 2 Tutorials
• ros2_control Documentation
• Gazebo Harmonic Documentation
• PX4 Autopilot Docs
• gz_ros2_control GitHub

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✨ TODO

• Add unit tests for controller plugins.
• Extend manipulator control with MoveIt.
• Automate mesh/URDF installation without symlinks.

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📝 License

This project is licensed under the Apache 2.0 License.