自定义msg

ros 版本：kinetic
自定义test包的文件结构如下

|-- test
|   |-- CMakeLists.txt
|   |-- msg
|   |   `-- Complex.msg
|   |-- package.xml
|   |-- scripts
|   |   |-- message_publisher.py
|   |   `-- message_subscriber.py

1. 定义msg文件

Complex.msg #通常大写字母开头

float32 real
float32 imaginary

2. 修改 package.xml

向其中添加如下信息，首先是<build_depend>message_generation</build_depend>和<exec_depend>message_runtime</exec_depend>；其次，需要使用那些包就添加进去，例如 std_msgs，roscpp。

  <buildtool_depend>catkin</buildtool_depend><build_depend>rospy</build_depend><build_export_depend>rospy</build_export_depend><build_depend>message_generation</build_depend><build_depend>std_msgs</build_depend><build_depend>roscpp</build_depend><exec_depend>roscpp</exec_depend><exec_depend>rospy</exec_depend><exec_depend>message_runtime</exec_depend><exec_depend>std_msgs</exec_depend>

3. 修改 CMakeLists.txt

find_package(catkin REQUIRED COMPONENTSrospyroscppstd_msgsmessage_generation
)

添加自定义的msg文件

add_message_files(FILESComplex.msg
)

## Generate added messages and services with any dependencies listed here
generate_messages(DEPENDENCIESstd_msgs  # Or other packages containing msgs
)

catkin_package(
#   INCLUDE_DIRS include
#   LIBRARIES testCATKIN_DEPENDS rospy message_runtime std_msgs roscpp
#   DEPENDS system_lib
)

## Mark executable scripts (Python etc.) for installation
## in contrast to setup.py, you can choose the destination
catkin_install_python(PROGRAMSscripts/message_publisher.pyscripts/message_subscriber.pyDESTINATION ${CATKIN_PACKAGE_BIN_DESTINATION}
)

4. message_publisher.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-import rospy
from test.msg import Complex
from random import randomrospy.init_node("message_publisher")
pub = rospy.Publisher("complex", Complex)rate = rospy.Rate(2)while not rospy.is_shutdown():msg = Complex()msg.real = random()msg.imaginary = random()pub.publish(msg)rate.sleep()

5. message_subscriber.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-import rospy
from test.msg import Complexdef callback(msg):print("real:", msg.real)print("imaginary:", msg.imaginary)print("\n") rospy.init_node("message_subscriber")
sub = rospy.Subscriber("complex", Complex, callback)rospy.spin()

6. 运行 catkin build

测试

roscore

rosrun test message_publisher.py

rosrun test message_subscriber.py

rqt_graph  #看一下 ros 节点图