Ros.3 自定义话题消息

1、定义

在功能包的下新建msg目录 新建Person.msg文件

#Person.msg
string name
uint8 sex
uint8 age

uint8 unknown=0
uint8 male=1
uint8 female=2

image.png

保证添加这以下两行

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

image.png

CMakeLists.txt
中修改

...
find_package(catkin REQUIRED COMPONENTS
  roscpp
  rospy
  std_msgs
  message_generation
)
...
find_package中添加 message_generation

catkin_package(
  INCLUDE_DIRS include
  LIBRARIES learning2
  CATKIN_DEPENDS roscpp rospy std_msgs message_runtime
  DEPENDS system_lib
)

catkin_package 添加 message_runtime
 add_message_files(
   FILES
   Person.msg
 )

add_message_files 添加  Person.msg 即创建的文件

 generate_messages(
   DEPENDENCIES
   std_msgs
 )

完成后编译
catkin_make

不能导出生成的类时 catkin_make install
https://answers.ros.org/question/105711/rospy-custom-message-importerror-no-module-named-msg/

rosmsg show Person

image.png

2、使用

#!/usr/bin/env python
# license removed for brevity
# talker.py

import rospy
from std_msgs.msg import String
from learning2.msg import Person  # learning2功能包的名称


def talker():
     pub = rospy.Publisher('chatter', Person, queue_size=10)
     rospy.init_node('talker', anonymous=True)
     rate = rospy.Rate(10) # 10hz
     while not rospy.is_shutdown():
           pub.publish(Person("xx",3,3))
           rate.sleep()
   
if __name__ == '__main__':
       try:
           talker()
       except rospy.ROSInterruptException:
           pass