学习资料主要源自http://wiki.ros.org/ROS/Tutorials/WritingPublisherSubscriber%28c%2B%2B%29

$ roscd beginner_tutorials/

$ mkdir -p src

$ cd src

$ gedit talker.cpp

1. 编写发布器节点 talker

#include "ros/ros.h"#include"std_msgs/String.h"#include

int main(int argc, char **argv)

{//初始化ROS，名称重映射(唯一)，必须为base name，不含/

ros::init(argc, argv, "talker");//为进程的节点创建一个句柄，第一个创建的NodeHandle初始化节点

ros::NodeHandle n;//告诉主机要在chatter topic上发布一个std_msgs消息//主机会订阅所有chatter topic节点，参数表示发布队列的大小(先进先出)

ros::Publisher chatter_pub = n.advertise<:string>("chatter", 1000);

ros::Rate loop_rate(10); //自循环频率

int count = 0;while(ros::ok())

{

std_msgs::String msg;

std::stringstream ss;

ss<< "hello world" <

msg.data=ss.str();//输出，用来替代prinf/cout

ROS_INFO("%s", msg.data.c_str());

chatter_pub.publish(msg);

ros::spinOnce();//休眠，来使发布频率为10Hz

loop_rate.sleep();++count;

}return 0;

}

实现功能：

(1) 初始化ROS系统

(2) 在chatter topic上发布std_msgs/String消息

(3) 以每秒10次频率发布消息

2. 编写订阅器节点

#include "ros/ros.h"#include"std_msgs/String.h"

//回调函数

void chatterCallback(const std_msgs::String::ConstPtr&msg)

{

ROS_INFO("I heard: [%s]", msg->data.c_str());

}int main(int argc, char **argv)

{

ros::init(argc, argv,"listener");

ros::NodeHandle n;//告诉master需要订阅chatter topic消息

ros::Subscriber sub = n.subscribe("chatter", 1000, chatterCallback);

ros::spin();//自循环

return 0;

}

实现功能：

(1) 初始化ROS系统

(2) 订阅chatter topic消息

(3) 进入自循环，等待消息到达

(4) 消息到达，调用chatterCallback()函数

3. src/ /CMakeLists.txt

cmake_minimum_required(VERSION 2.8.3)

project(beginner_tutorials)

## Find catkin and any catkin packages

find_package(catkin REQUIRED COMPONENTS

roscpp

rospy

std_msgs

message_generation

)

## Declare ROS messages and services

add_message_files(

FILES

Num.msg

)

add_service_files(

FILES

AddTwoInts.srv

)

## Declare a catkin package

catkin_package(

CATKIN_DEPENDS message_runtime

)

## Build talker and listener

include_directories(include

${catkin_INCLUDE_DIRS}

)

add_executable(talker src/talker.cpp)

target_link_libraries(talker ${catkin_LIBRARIES})

add_dependencies(talker beginner_tutorials_generate_messages_cpp)

add_executable(listener src/listener.cpp)

target_link_libraries(listener ${catkin_LIBRARIES})

add_dependencies(listener beginner_tutorials_generate_messages_cpp)

$ rosrun rqt_graph rqt_graph 或直接rqt_graph

注：如果遇到Couldn't find executable named talker below */src/beginner_tutorials

很有可能是工作空间初始化的问题。

参考

http://wiki.ros.org/ROS/Tutorials