py版本

Author: HuangCongQing

catkin_wp/src/learning_topic/script/velocity_publisher.py

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+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+########################################################################
+####          Copyright 2020 GuYueHome (www.guyuehome.com).          ###
+########################################################################
+
+# 该例程将发布turtle1/cmd_vel话题，消息类型geometry_msgs::Twist
+
+import rospy
+from geometry_msgs.msg import Twist
+
+def velocity_publisher():
+	# ROS节点初始化
+    rospy.init_node('velocity_publisher', anonymous=True)
+
+	# 创建一个Publisher，发布名为/turtle1/cmd_vel的topic，消息类型为geometry_msgs::Twist，队列长度10
+    turtle_vel_pub = rospy.Publisher('/turtle1/cmd_vel', Twist, queue_size=10)
+
+	#设置循环的频率
+    rate = rospy.Rate(10) 
+
+    while not rospy.is_shutdown():
+		# 初始化geometry_msgs::Twist类型的消息
+        vel_msg = Twist()
+        vel_msg.linear.x = 0.5
+        vel_msg.angular.z = 0.2
+
+		# 发布消息
+        turtle_vel_pub.publish(vel_msg)
+    	rospy.loginfo("Publsh turtle velocity command[%0.2f m/s, %0.2f rad/s]", 
+				vel_msg.linear.x, vel_msg.angular.z)
+
+		# 按照循环频率延时
+        rate.sleep()
+
+if __name__ == '__main__':
+    try:
+        velocity_publisher()
+    except rospy.ROSInterruptException:
+        pass