ROS custom message

1. 패키지 및 작업 폴더 생성

cd ~/${workspack_name}/src # cd ~/ros_ws/src
catkin_create_pkg ${package_name} rospy std_msgs # catkin_create_pkg custom_message rospy std_msgs
cd ../ && catkin_make
rospack find ${package_name} # rospack find custom_message
cd src/${package_name} # cd src/custom_message
mkdir msg
mkdir launch

 

2. 메시지 형식 정의

• cd msg로 폴더를 이동한 뒤, vi person.msg 파일을 만들고 아래의 내용을 작성한다.

  string first_name
  string last_name
  uint8 age
  uint32 score

• rosmsg show person으로 메시지가 등록되었는지 확인한다

  

 

 

3. 구성 파일 변경

• cd ../로 패키지 경로로 이동한다

• package.xml에 다음의 내용을 추가한다

  <build_depend>message_generation</build_depend>
  <exec_depend>message_runtime</exec_depend>

  

• CMakeLists.txt 파일을 다음을 참고하여 수정한다
  • 전체 파일

    cmake_minimum_required(VERSION 3.0.2)
    project(custom_message)
    
    ## Compile as C++11, supported in ROS Kinetic and newer
    # add_compile_options(-std=c++11)
    
    ## Find catkin macros and libraries
    ## if COMPONENTS list like find_package(catkin REQUIRED COMPONENTS xyz)
    ## is used, also find other catkin packages
    find_package(catkin REQUIRED COMPONENTS
        roscpp
        rospy
        std_msgs
        message_generation
    )
    
    ## System dependencies are found with CMake's conventions
    # find_package(Boost REQUIRED COMPONENTS system)
    
    
    ## Uncomment this if the package has a setup.py. This macro ensures
    ## modules and global scripts declared therein get installed
    ## See http://ros.org/doc/api/catkin/html/user_guide/setup_dot_py.html
    # catkin_python_setup()
    
    ################################################
    ## Declare ROS messages, services and actions ##
    ################################################
    
    ## To declare and build messages, services or actions from within this
    ## package, follow these steps:
    ## * Let MSG_DEP_SET be the set of packages whose message types you use in
    ##   your messages/services/actions (e.g. std_msgs, actionlib_msgs, ...).
    ## * In the file package.xml:
    ##   * add a build_depend tag for "message_generation"
    ##   * add a build_depend and a exec_depend tag for each package in MSG_DEP_SET
    ##   * If MSG_DEP_SET isn't empty the following dependency has been pulled in
    ##     but can be declared for certainty nonetheless:
    ##     * add a exec_depend tag for "message_runtime"
    ## * In this file (CMakeLists.txt):
    ##   * add "message_generation" and every package in MSG_DEP_SET to
    ##     find_package(catkin REQUIRED COMPONENTS ...)
    ##   * add "message_runtime" and every package in MSG_DEP_SET to
    ##     catkin_package(CATKIN_DEPENDS ...)
    ##   * uncomment the add_*_files sections below as needed
    ##     and list every .msg/.srv/.action file to be processed
    ##   * uncomment the generate_messages entry below
    ##   * add every package in MSG_DEP_SET to generate_messages(DEPENDENCIES ...)
    
    ## Generate messages in the 'msg' folder
    add_message_files(
        FILES
        person.msg
        # Message1.msg
        # Message2.msg
    )
    
    ## Generate services in the 'srv' folder
    # add_service_files(
    #   FILES
    #   Service1.srv
    #   Service2.srv
    # )
    
    ## Generate actions in the 'action' folder
    # add_action_files(
    #   FILES
    #   Action1.action
    #   Action2.action
    # )
    
    ## Generate added messages and services with any dependencies listed here
    generate_messages(
        DEPENDENCIES
        std_msgs
    )
    
    ################################################
    ## Declare ROS dynamic reconfigure parameters ##
    ################################################
    
    ## To declare and build dynamic reconfigure parameters within this
    ## package, follow these steps:
    ## * In the file package.xml:
    ##   * add a build_depend and a exec_depend tag for "dynamic_reconfigure"
    ## * In this file (CMakeLists.txt):
    ##   * add "dynamic_reconfigure" to
    ##     find_package(catkin REQUIRED COMPONENTS ...)
    ##   * uncomment the "generate_dynamic_reconfigure_options" section below
    ##     and list every .cfg file to be processed
    
    ## Generate dynamic reconfigure parameters in the 'cfg' folder
    # generate_dynamic_reconfigure_options(
    #   cfg/DynReconf1.cfg
    #   cfg/DynReconf2.cfg
    # )
    
    ###################################
    ## catkin specific configuration ##
    ###################################
    ## The catkin_package macro generates cmake config files for your package
    ## Declare things to be passed to dependent projects
    ## INCLUDE_DIRS: uncomment this if your package contains header files
    ## LIBRARIES: libraries you create in this project that dependent projects also need
    ## CATKIN_DEPENDS: catkin_packages dependent projects also need
    ## DEPENDS: system dependencies of this project that dependent projects also need
    catkin_package(
        CATKIN_DEPENDS message_runtime
    #  INCLUDE_DIRS include
    #  LIBRARIES msg_send
    #  CATKIN_DEPENDS rospy std_msgs
    #  DEPENDS system_lib
    )
    
    ###########
    ## Build ##
    ###########
    
    ## Specify additional locations of header files
    ## Your package locations should be listed before other locations
    include_directories(
    # include
        ${catkin_INCLUDE_DIRS}
    )
    
    ## Declare a C++ library
    # add_library(${PROJECT_NAME}
    #   src/${PROJECT_NAME}/custom_message.cpp
    # )
    
    ## Add cmake target dependencies of the library
    ## as an example, code may need to be generated before libraries
    ## either from message generation or dynamic reconfigure
    # add_dependencies(${PROJECT_NAME} ${${PROJECT_NAME}_EXPORTED_TARGETS} ${catkin_EXPORTED_TARGETS})
    
    ## Declare a C++ executable
    ## With catkin_make all packages are built within a single CMake context
    ## The recommended prefix ensures that target names across packages don't collide
    # add_executable(${PROJECT_NAME}_node src/custom_message_node.cpp)
    
    ## Rename C++ executable without prefix
    ## The above recommended prefix causes long target names, the following renames the
    ## target back to the shorter version for ease of user use
    ## e.g. "rosrun someones_pkg node" instead of "rosrun someones_pkg someones_pkg_node"
    # set_target_properties(${PROJECT_NAME}_node PROPERTIES OUTPUT_NAME node PREFIX "")
    
    ## Add cmake target dependencies of the executable
    ## same as for the library above
    # add_dependencies(${PROJECT_NAME}_node ${${PROJECT_NAME}_EXPORTED_TARGETS} ${catkin_EXPORTED_TARGETS})
    
    ## Specify libraries to link a library or executable target against
    # target_link_libraries(${PROJECT_NAME}_node
    #   ${catkin_LIBRARIES}
    # )
    
    #############
    ## Install ##
    #############
    
    # all install targets should use catkin DESTINATION variables
    # See http://ros.org/doc/api/catkin/html/adv_user_guide/variables.html
    
    ## Mark executable scripts (Python etc.) for installation
    ## in contrast to setup.py, you can choose the destination
    # catkin_install_python(PROGRAMS
    #   scripts/my_python_script
    #   DESTINATION ${CATKIN_PACKAGE_BIN_DESTINATION}
    # )
    
    ## Mark executables for installation
    ## See http://docs.ros.org/melodic/api/catkin/html/howto/format1/building_executables.html
    # install(TARGETS ${PROJECT_NAME}_node
    #   RUNTIME DESTINATION ${CATKIN_PACKAGE_BIN_DESTINATION}
    # )
    
    ## Mark libraries for installation
    ## See http://docs.ros.org/melodic/api/catkin/html/howto/format1/building_libraries.html
    # install(TARGETS ${PROJECT_NAME}
    #   ARCHIVE DESTINATION ${CATKIN_PACKAGE_LIB_DESTINATION}
    #   LIBRARY DESTINATION ${CATKIN_PACKAGE_LIB_DESTINATION}
    #   RUNTIME DESTINATION ${CATKIN_GLOBAL_BIN_DESTINATION}
    # )
    
    ## Mark cpp header files for installation
    # install(DIRECTORY include/${PROJECT_NAME}/
    #   DESTINATION ${CATKIN_PACKAGE_INCLUDE_DESTINATION}
    #   FILES_MATCHING PATTERN "*.h"
    #   PATTERN ".svn" EXCLUDE
    # )
    
    ## Mark other files for installation (e.g. launch and bag files, etc.)
    # install(FILES
    #   # myfile1
    #   # myfile2
    #   DESTINATION ${CATKIN_PACKAGE_SHARE_DESTINATION}
    # )
    
    #############
    ## Testing ##
    #############
    
    ## Add gtest based cpp test target and link libraries
    # catkin_add_gtest(${PROJECT_NAME}-test test/test_custom_message.cpp)
    # if(TARGET ${PROJECT_NAME}-test)
    #   target_link_libraries(${PROJECT_NAME}-test ${PROJECT_NAME})
    # endif()
    
    ## Add folders to be run by python nosetests
    # catkin_add_nosetests(test)

  find_package(catkin REQUIRED COMPONENTS
      roscpp
  + rospy
      std_msgs
  + message_generation
  )
  
  +add_message_files(
      FILES
      person.msg
      # Message1.msg
      # Message2.msg
  +)
  
  +generate_messages(
  + DEPENDENCIES
  + std_msgs
  +)
  
  catkin_package(
  + CATKIN_DEPENDS message_runtime
  #  INCLUDE_DIRS include
  #  LIBRARIES msg_send
  #  CATKIN_DEPENDS rospy std_msgs
  #  DEPENDS system_lib
  )

• cd ../ && catkin_make로 패키지가 제대로 빌드되는지 확인한다

 

 

4. 커스텀 메시지를 불러온 Publisher, Subscriber 작성

• src에 publisher.py을 만들고 아래의 내용을 작성한다

  #!/usr/bin/env python
  # license removed for brevity
  import rospy
  from custom_message.msg import person
  
  def talker():
      pub = rospy.Publisher('chatter', person, queue_size=10)
      rospy.init_node('talker', anonymous=True)
      rate = rospy.Rate(10) # 10hz
  
      msg = person()
      msg.first_name = "gildon"
      msg.last_name = "Hong"
      msg.age = 24
      msg.score = 95
  
      while not rospy.is_shutdown():
          rospy.loginfo(msg)
          pub.publish(msg)
          rate.sleep()
  
  if __name__ == '__main__':
      try:
          talker()
      except rospy.ROSInterruptException:
          pass

• src에 subscriber.py을 만들고 아래의 내용을 작성한다

  #!/usr/bin/env python
  import rospy
  from custom_message.msg import person
  
  def callback(msg):
      print ("1. Name: ", msg.last_name + msg.first_name)
      print ("2. Age: ", msg.age)
      print ("3. Score: " , msg.score)
      
  def listener():
  
      # In ROS, nodes are uniquely named. If two nodes with the same
      # name are launched, the previous one is kicked off. The
      # anonymous=True flag means that rospy will choose a unique
      # name for our 'listener' node so that multiple listeners can
      # run simultaneously.
      rospy.init_node('listener', anonymous=True)
  
      rospy.Subscriber("chatter", person, callback)
  
      # spin() simply keeps python from exiting until this node is stopped
      rospy.spin()
  
  if __name__ == '__main__':
      listener()

• 파일을 실행할 수 있도록, chmod +x *.py로 명령어를 실행한다

 

 

5. launch 파일 생성

• launch 폴더에 communication.launch 파일을 생성한 뒤, 아래의 내용을 작성한다

  <launch>
      <node pkg="custom_message" type="publisher.py" name="publisher"/>
      <node pkg="custom_message" type="subscriber.py" name="subscriber" output="screen"/>
  </launch>

 

 

6. 노드 실행

• roslaunch custom_message communication.launch로 노드를 실행해본다

  

 

 

7. 참고

ROS/Tutorials/CreatingMsgAndSrv - ROS Wiki

http://wiki.ros.org/ROS/Tutorials/CreatingMsgAndSrv#Creating_a_msg

ros_ws/src/custom_message at master · SwimingKim/ros_ws

Contribute to SwimingKim/ros_ws development by creating an account on GitHub.

https://github.com/SwimingKim/ros_ws/tree/master/src/custom_message