ROS1 vs ROS2 Comprehensive Comparison (3)

-

Package Configuration Files

package.xml Examples

ROS1 package.xml (Format 2) ROS2 package.xml (Format 3) 
<?xml version="1.0"?>
<package format="2">
  <name>my_ros1_package</name>
  <version>0.1.0</version>
  <description>
    A package for ROS1
  </description>
  
  <maintainer email="user@example.com">Your Name</maintainer>
  <license>BSD</license>
  <url type="website">http://wiki.ros.org/my_ros1_package</url>
  <author email="user@example.com">Your Name</author>

  <buildtool_depend>catkin</buildtool_depend>
  
  <build_depend>roscpp</build_depend>
  <build_depend>rospy</build_depend>
  <build_depend>std_msgs</build_depend>
  
  <exec_depend>roscpp</exec_depend>
  <exec_depend>rospy</exec_depend>
  <exec_depend>std_msgs</exec_depend>

  <export>
    <!-- Other tools can request additional information be placed here -->
  </export>
</package>
      
<?xml version="1.0"?>
<?xml-model href="http://download.ros.org/schema/package_format3.xsd" schematypens="http://www.w3.org/2001/XMLSchema"?>
<package format="3">
  <name>my_ros2_package</name>
  <version>0.1.0</version>
  <description>
    A package for ROS2
  </description>
  
  <maintainer email="user@example.com">Your Name</maintainer>
  <license>Apache License 2.0</license>
  <url type="website">https://github.com/user/my_ros2_package</url>
  <author email="user@example.com">Your Name</author>

  <buildtool_depend>ament_cmake</buildtool_depend>
  
  <depend>rclcpp</depend>
  <depend>std_msgs</depend>
  <exec_depend>ros2launch</exec_depend>
  
  <test_depend>ament_lint_auto</test_depend>
  <test_depend>ament_lint_common</test_depend>

  <export>
    <build_type>ament_cmake</build_type>
  </export>
</package>
ROS1 package.xml for Python package ROS2 package.xml for Python package 
<?xml version="1.0"?>
<package format="2">
  <name>my_ros1_py_pkg</name>
  <version>0.1.0</version>
  <description>
    A Python package for ROS1
  </description>
  
  <maintainer email="user@example.com">Your Name</maintainer>
  <license>BSD</license>

  <buildtool_depend>catkin</buildtool_depend>
  
  <build_depend>rospy</build_depend>
  <build_depend>std_msgs</build_depend>
  
  <exec_depend>rospy</exec_depend>
  <exec_depend>std_msgs</exec_depend>

  <export>
    <!-- Other tools can request additional information be placed here -->
  </export>
</package>
      
<?xml version="1.0"?>
<?xml-model href="http://download.ros.org/schema/package_format3.xsd" schematypens="http://www.w3.org/2001/XMLSchema"?>
<package format="3">
  <name>my_ros2_py_pkg</name>
  <version>0.1.0</version>
  <description>
    A Python package for ROS2
  </description>
  
  <maintainer email="user@example.com">Your Name</maintainer>
  <license>Apache License 2.0</license>

  <exec_depend>rclpy</exec_depend>
  <exec_depend>std_msgs</exec_depend>
  
  <test_depend>ament_copyright</test_depend>
  <test_depend>ament_flake8</test_depend>
  <test_depend>ament_pep257</test_depend>
  <test_depend>python3-pytest</test_depend>

  <export>
    <build_type>ament_python</build_type>
  </export>
</package>
ROS1 package.xml with conditional dependencies ROS2 package.xml with conditional dependencies 
<!-- Not supported in ROS1 -->
      
<?xml version="1.0"?>
<?xml-model href="http://download.ros.org/schema/package_format3.xsd" schematypens="http://www.w3.org/2001/XMLSchema"?>
<package format="3">
  <name>cross_compatible_pkg</name>
  <version>0.1.0</version>
  <description>
    A package compatible with both ROS1 and ROS2
  </description>
  
  <maintainer email="user@example.com">Your Name</maintainer>
  <license>Apache License 2.0</license>

  <buildtool_depend condition="$ROS_VERSION == 1">catkin</buildtool_depend>
  <buildtool_depend condition="$ROS_VERSION == 2">ament_cmake</buildtool_depend>
  
  <depend condition="$ROS_VERSION == 1">roscpp</depend>
  <depend condition="$ROS_VERSION == 2">rclcpp</depend>
  
  <depend>std_msgs</depend> <!-- Common dependency for both ROS versions -->

  <export>
    <build_type condition="$ROS_VERSION == 1">catkin</build_type>
    <build_type condition="$ROS_VERSION == 2">ament_cmake</build_type>
  </export>
</package>

setup.py Examples

ROS1 setup.py ROS2 setup.py 
## ! DO NOT MANUALLY INVOKE THIS setup.py, USE CATKIN INSTEAD

from distutils.core import setup
from catkin_pkg.python_setup import generate_distutils_setup

# fetch values from package.xml
setup_args = generate_distutils_setup(
    packages=['my_ros1_py_pkg'],
    package_dir={'': 'src'},
)

setup(**setup_args)
      
from setuptools import setup
import os
from glob import glob

package_name = 'my_ros2_py_pkg'

setup(
    name=package_name,
    version='0.1.0',
    packages=[package_name],
    data_files=[
        # Include our package.xml file
        ('share/ament_index/resource_index/packages',
            ['resource/' + package_name]),
        ('share/' + package_name, ['package.xml']),
        # Include all launch files.
        (os.path.join('share', package_name, 'launch'),
         glob(os.path.join('launch', '*.launch.py'))),
    ],
    install_requires=['setuptools'],
    zip_safe=True,
    maintainer='Your Name',
    maintainer_email='user@example.com',
    description='A Python package for ROS2',
    license='Apache License 2.0',
    tests_require=['pytest'],
    entry_points={
        'console_scripts': [
            'talker = my_ros2_py_pkg.publisher_node:main',
            'listener = my_ros2_py_pkg.subscriber_node:main',
        ],
    },
)

setup.cfg Example (ROS2 only)

[develop]
script-dir=$base/lib/my_ros2_py_pkg

[install]
install-scripts=$base/lib/my_ros2_py_pkg

Key Differences in Configuration Files

Feature ROS1 ROS2
package.xml Format Format 1 or 2 Format 3 (adds conditional dependencies)
Python Package Processing Limited by catkin, uses catkin_pkg.python_setup.generate_distutils_setup Full setuptools functionality, direct setup() call
Executable Registration Scripts are placed in a scripts/ directory and made executable Uses Python entry_points in setup.py
Data Files Usually handled in CMakeLists.txt Specified in setup.py data_files list
setup.cfg Not typically used Required for Python packages to specify script installation directory
Build Tool Declaration Always catkin ament_cmake for C++, ament_python for Python
Cross-ROS Compatibility Not supported Supported with conditional expressions in package.xml format 3

CMakeLists.txt Comparison

Feature ROS1 (Catkin) ROS2 (Ament)
Minimum Structure 
cmake_minimum_required(VERSION 2.8.3)
project(my_package)

find_package(catkin REQUIRED COMPONENTS
  roscpp
  std_msgs
)

catkin_package()

include_directories(
  include
  ${catkin_INCLUDE_DIRS}
)

add_executable(my_node src/my_node.cpp)
target_link_libraries(my_node
  ${catkin_LIBRARIES}
)

install(TARGETS my_node
  RUNTIME DESTINATION ${CATKIN_PACKAGE_BIN_DESTINATION}
)
      
cmake_minimum_required(VERSION 3.8)
project(my_package)

# Default to C++14
if(NOT CMAKE_CXX_STANDARD)
  set(CMAKE_CXX_STANDARD 14)
endif()

find_package(ament_cmake REQUIRED)
find_package(rclcpp REQUIRED)
find_package(std_msgs REQUIRED)

add_executable(my_node src/my_node.cpp)
target_include_directories(my_node PUBLIC
  $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
  $<INSTALL_INTERFACE:include>
)
ament_target_dependencies(my_node
  rclcpp
  std_msgs
)

install(TARGETS my_node
  DESTINATION lib/${PROJECT_NAME}
)

ament_package()
Package Dependencies 
find_package(catkin REQUIRED COMPONENTS
  roscpp
  rospy
  std_msgs
  geometry_msgs
)
      
find_package(ament_cmake REQUIRED)
find_package(rclcpp REQUIRED)
find_package(std_msgs REQUIRED)
find_package(geometry_msgs REQUIRED)
Include Directories 
include_directories(
  include
  ${catkin_INCLUDE_DIRS}
)
      
# Per-target approach (preferred)
target_include_directories(my_target PUBLIC
  $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>
  $<INSTALL_INTERFACE:include>
)
Link Libraries 
target_link_libraries(my_node
  ${catkin_LIBRARIES}
)
      
# Target-specific dependencies using modern CMake
target_link_libraries(my_node
  PUBLIC
    ${std_msgs_TARGETS}
    another_lib::another_lib
)
Package Export 
catkin_package(
  INCLUDE_DIRS include
  LIBRARIES my_library
  CATKIN_DEPENDS roscpp std_msgs
  DEPENDS system_lib
)
      
# Not explicitly required with target-based approach
# Dependencies are handled through ament_target_dependencies
# and target_link_libraries

# To export dependencies:
ament_export_targets(export_my_package HAS_LIBRARY_TARGET)
ament_export_dependencies(rclcpp std_msgs)
Message Generation 
find_package(catkin REQUIRED COMPONENTS
  std_msgs
  message_generation
)

add_message_files(
  FILES
  MyMessage.msg
)

add_service_files(
  FILES
  MyService.srv
)

generate_messages(
  DEPENDENCIES
  std_msgs
)

catkin_package(
  CATKIN_DEPENDS message_runtime std_msgs
)
      
find_package(rosidl_default_generators REQUIRED)
find_package(std_msgs REQUIRED)

rosidl_generate_interfaces(${PROJECT_NAME}
  "msg/MyMessage.msg"
  "srv/MyService.srv"
  DEPENDENCIES std_msgs
)

# To use interfaces in the same package:
rosidl_target_interfaces(my_node ${PROJECT_NAME} "rosidl_typesupport_cpp")

# In package.xml:
# <member_of_group>rosidl_interface_packages</member_of_group>
# <build_depend>rosidl_default_generators</build_depend>
# <exec_depend>rosidl_default_runtime</exec_depend>
Installation 
install(TARGETS my_node my_library
  ARCHIVE DESTINATION ${CATKIN_PACKAGE_LIB_DESTINATION}
  LIBRARY DESTINATION ${CATKIN_PACKAGE_LIB_DESTINATION}
  RUNTIME DESTINATION ${CATKIN_PACKAGE_BIN_DESTINATION}
)

install(DIRECTORY include/${PROJECT_NAME}/
  DESTINATION ${CATKIN_PACKAGE_INCLUDE_DESTINATION}
  FILES_MATCHING PATTERN "*.h"
)

install(DIRECTORY launch/
  DESTINATION ${CATKIN_PACKAGE_SHARE_DESTINATION}/launch
)
      
install(TARGETS my_node my_library
  EXPORT export_my_package
  ARCHIVE DESTINATION lib
  LIBRARY DESTINATION lib
  RUNTIME DESTINATION lib/${PROJECT_NAME}
)

install(
  DIRECTORY include/
  DESTINATION include
)

install(
  DIRECTORY launch
  DESTINATION share/${PROJECT_NAME}
)
Testing 
if(CATKIN_ENABLE_TESTING)
  catkin_add_gtest(my_test test/test.cpp)
  target_link_libraries(my_test ${catkin_LIBRARIES})
endif()
      
if(BUILD_TESTING)
  find_package(ament_lint_auto REQUIRED)
  find_package(ament_cmake_gtest REQUIRED)
  
  ament_lint_auto_find_test_dependencies()
  
  ament_add_gtest(my_test test/test.cpp)
  target_link_libraries(my_test
    my_library
  )
endif()
Finalization 
# Not required, handled by catkin_package()
      
# Always required as the last CMake command
ament_package()
Python Modules Support 
catkin_python_setup()

# Refers to setup.py in the package
      
# For pure Python packages: use ament_python build type
# For mixed C++/Python packages:
find_package(ament_cmake_python REQUIRED)

ament_python_install_package(${PROJECT_NAME})

# Install Python executables
install(PROGRAMS
  scripts/my_python_script.py
  DESTINATION lib/${PROJECT_NAME}
)

Key Differences in CMakeLists.txt

Aspect ROS1 (Catkin) ROS2 (Ament)
CMake Version Typically 2.8.3+ Typically 3.5+ (3.8+ for newer distributions)
Build System catkin ament_cmake, ament_python
Dependency Handling Centralized through catkin Per-package find_package calls
Include Paths Global via include_directories Per-target via target_include_directories
Library Linking Often uses ${catkin_LIBRARIES} Modern CMake target-based approach
Package Export Through catkin_package() Through ament_export_* functions
Message Generation Multi-step with add_*_files and generate_messages Single call to rosidl_generate_interfaces
Installation Paths Uses CATKIN_* variables More direct paths, lib/${PROJECT_NAME}
Final Function None required (catkin_package is typically not at the end) ament_package() required at the end

留言

張貼留言

這個網誌中的熱門文章

Useful PX4 Parameters

-
1. For setting companion link SYS_COMPANION (Before ver. 1.9.0) MAV_0_CONFIG, MAV_0_MODE (After ver. 1.9.0) 2. EKF2 configuration EKF2_AID_MASK EKF2_HGT_MODE EKF2_EV_DELAY (Reduce this parameter if high rate external vision is available) EKF2_EV_POS_X, EKF2_EV_POS_Y, EKF2_EV_POS_Z 3. Offboard mode parameters ( The vehicle will exit the mode if target setpoints are not received at a rate of > 2Hz ) COM_OBL_RC_ACT (Default: position mode, I set land mode) COM_OBL_ACT COM_OF_LOSS_T 4. Position loss failsafe COM_POSCTL_NAVL 5. Land mode MPC_LAND_SPEED COM_DISARM_LAND: Time-out for auto disarm after landing. (Default: 0, I set 3.) 6. TBD Reference: [1]  https://dev.px4.io/en/advanced/parameter_reference.html [2]  https://dev.px4.io/en/ros/external_position_estimation.html#tuning-EKF2_EV_DELAY [3]  https://docs.px4.io/en/config/safety.html#qgc_safety_setup
閱讀完整內容

Tuing PID parameters in QGroundcontrol (2)

-
圖片
Based on tips for tuning PX4 PID parameters written in my previous post [1] or even using the default values directly, you will be able to fly your vehicle freely in manual or stabilized flight mode.   However, if you are using an unique vehicle (usually assembly by yourself and only equipped with sensors you desire) and struggling for finding the best PID parameters for your applications. I think following 8 tips will help you to get ideal PID parameters.  This is the vehicle I made based on LHI QAV250 fiber frame, with TX2, high-speed camera, etc.[2]  Tip1:  Tuning order: Rate controller -> attitude controller -> position controller The PX4 controllers are layered [3], which means a higher-level controller passes its results to a lower-level controller. Thus the PID tuning needs to be done from lowest-level controller to highest-level controller. Tip2:  Check if  PWM_MIN  is set correctly. Remove propellers Arm the vehic...
閱讀完整內容

Matlab Pixhawk Support Package installation (Windows)

-
圖片
1. Download the pixhawk support package [1] 2. Open MATLAB R2017b and navigate to the file location. 3. Click "PX4PSP_v3_0_4_351_R2017b" and install it 4. Create a folder for firmware download path (ex: D/PX4) 5. Setting bash environment for windows 10 [2]  (1) Active "Windows subsystem for linux" (2) Download and install Ubuntu (3) Using the terminal like in Ubuntu environment ex: 6. Install all necessary toolchain with " windows_bash_nuttx.sh " [3] or using Cygwin Toolchian [4] or [5] (python27 would show in following folder) 7. Key in command " PixhawkPSP(' D:\PX4 ') " in the Matlab 8. Make sure windows 10 bash and python path are correct => Validate paths 9. Download firmware to the folder we specify before and then validate firmware. 10. Selecting cmake configuration [6] 11. Build firmware *Error: make command not found   Solution: [7] T...
閱讀完整內容