Ros机器人之（四）发布Publisher消息

从基础学习，发布消息Publisher
首先创建功能包,命令+名称+功能包依赖

catkin_create_pkg learning-topic roscpp rospy std_msgs geometry_msgs turtlesim

src文件夹下创建一个publisher.cpp

touch publisher.cpp

内容如下：

/*
publisher topic
*/

#include<ros/ros.h>
#include<geometry_msgs/Twist.h>

int main(int argc, char**argv){
	//初始节点化
	ros::init(argc,argv,"publisher");
	//创建节点句柄
	ros::NodeHandle n;
	//创建发布者，发布的话题及队列长度用于缓存
	ros::Publisher turtle_vel_pub = n.advertise<geometry_msgs::Twist>("/turtle1/cmd_vel",10);
	//循环频率
	ros::Rate loop_rate(10);
	int count=0;
	//循环
	while(ros::ok())
	{	
		//定义vek_msg 对象
		geometry_msgs::Twist vel_msg;
		//线速度
		vel_msg.linear.x = 0.5;
		vel_msg.angular.z = 0.2;
		//发布出去
		turtle_vel_pub.publish(vel_msg);
		//显示消息
		ROS_INFO("Publish command[%0.2f,%0.2f]",vel_msg.linear.x,vel_msg.angular.z);
		//按照设置的频率循环
		loop_rate.sleep();
	}
	return 0;
}

完成后在Cmakelists中添加

#把cpp编译成publisher
add_executable(publisher src/publisher.cpp)
#将publisher进行接口链接
target_link_libraries(publisher ${catkin_LIBRARIES})

完成后，工作区的根目录下进行编译并设置环境变量。

catkin_make
source devel/setup.bash

完成后运行小乌龟

roscore
rosrun turtlesim turtlesim_node

运行发布节点

rosrun learning_topic publisher