Table of Contents

Overview
#

ROS uses the catkin build system to manage packages. Understanding the workspace structure is essential for ROS development.

Catkin Workspace Structure
#

catkin_ws/
├── src/                 ← Source code
│   ├── CMakeLists.txt   ← Top-level cmake
│   ├── package1/
│   │   ├── CMakeLists.txt
│   │   ├── package.xml
│   │   ├── src/
│   │   ├── include/
│   │   └── launch/
│   └── package2/
├── build/               ← Build artifacts
├── devel/               ← Development environment
│   ├── setup.bash
│   ├── lib/
│   └── share/
└── install/             ← Installation (optional)

Directory Purposes
#

Source Space (src/)
#

Contains all package source code:

ContentsPurpose
Package directoriesIndividual ROS packages
CMakeLists.txtTop-level cmake file
.rosinstallWorkspace dependencies

Build Space (build/)
#

Compilation and dependency optimization:

  • CMake cache files
  • Makefile outputs
  • Intermediate build files

Devel Space (devel/)
#

Development environment ready for execution:

ContentsPurpose
setup.bashEnvironment setup script
lib/Compiled libraries
share/Package resources
bin/Executables

Install Space (install/)
#

Optional production deployment:

  • Isolated from build artifacts
  • Clean installation structure

Build Process
#

Workflow
#

Source Code → catkin_make → Build Directory → Devel/Install
                  │
                  ↓
            CMake + Make
                  │
                  ↓
           Compiled Binaries

Building Workspace
#

cd ~/catkin_ws
catkin_make

Clean Build
#

cd ~/catkin_ws
catkin_make clean
catkin_make

TurtleBot3 Packages
#

Example package structure:

src/
├── turtlebot3/
│   ├── turtlebot3_bringup/
│   ├── turtlebot3_description/
│   ├── turtlebot3_example/
│   ├── turtlebot3_navigation/
│   ├── turtlebot3_slam/
│   └── turtlebot3_teleop/
└── turtlebot3_simulations/
    ├── turtlebot3_gazebo/
    └── turtlebot3_fake/

Package Components
#

CMakeLists.txt
#

cmake_minimum_required(VERSION 3.0.2)
project(my_package)

find_package(catkin REQUIRED COMPONENTS
  rospy
  std_msgs
)

catkin_package()

include_directories(${catkin_INCLUDE_DIRS})

catkin_install_python(PROGRAMS
  scripts/my_node.py
  DESTINATION ${CATKIN_PACKAGE_BIN_DESTINATION}
)

package.xml
#

<?xml version="1.0"?>
<package format="2">
  <name>my_package</name>
  <version>0.0.1</version>
  <description>Package description</description>
  <maintainer email="user@example.com">User</maintainer>
  <license>MIT</license>

  <buildtool_depend>catkin</buildtool_depend>
  <depend>rospy</depend>
  <depend>std_msgs</depend>
</package>

Launch Files
#

<launch>
  <node pkg="my_package" type="my_node.py" name="my_node" output="screen">
    <param name="rate" value="10"/>
  </node>
</launch>

Environment Setup
#

Source Workspace
#

source ~/catkin_ws/devel/setup.bash

Add to Bashrc
#

echo "source ~/catkin_ws/devel/setup.bash" >> ~/.bashrc

Check Environment
#

echo $ROS_PACKAGE_PATH

Should include: /home/user/catkin_ws/src

Common Commands
#

CommandPurpose
catkin_makeBuild workspace
catkin_make -j4Build with 4 threads
catkin_make cleanClean build
rospack listList all packages
roscd package_nameNavigate to package

Best Practices
#

  1. One workspace for related packages
  2. Source devel/setup.bash after building
  3. Use package dependencies properly
  4. Document packages in package.xml
  5. Version control the src/ directory