网站建设app开发学习,线上营销活动主要有哪些,网页设计个人总结,基于WordPress开发目录如何实现一个服务器C编写程序配置CMakeLists.txt编译并运行python创建并编写脚本运行平台#xff1a;华硕 Thinker Edge R 瑞芯微 RK3399Pro 固件版本#xff1a;Tinker_Edge_R-Debian-Stretch-V1.0.4-20200615 记录自【古月居】古月ROS入门21讲 | 一学就会的ROS机器人入… 目录如何实现一个服务器C编写程序配置CMakeLists.txt编译并运行python创建并编写脚本运行平台华硕 Thinker Edge R 瑞芯微 RK3399Pro 固件版本Tinker_Edge_R-Debian-Stretch-V1.0.4-20200615 记录自【古月居】古月·ROS入门21讲 | 一学就会的ROS机器人入门教程 —— 古月居GYH P14 14.服务端Server的编程实现 如何实现一个服务器 初始化ROS节点创建Server实例循环等待服务请求进入回调函数在回调函数中完成服务功能的处理并反馈应答数据。 C 编写程序 nano ~/catkin_workspace/src/learning_service/src/turtle_command_server.cpp/*********************************************************************** Copyright 2020 GuYueHome (www.guyuehome.com). ***********************************************************************//*** 该例程将执行/turtle_command服务服务数据类型std_srvs/Trigger*/#include ros/ros.h #include geometry_msgs/Twist.h #include std_srvs/Trigger.hros::Publisher turtle_vel_pub; bool pubCommand false;// service回调函数输入参数req输出参数res bool commandCallback(std_srvs::Trigger::Request req,std_srvs::Trigger::Response res) {pubCommand !pubCommand;// 显示请求数据ROS_INFO(Publish turtle velocity command [%s], pubCommandtrue?Yes:No);// 设置反馈数据res.success true;res.message Change turtle command state!;return true; }int main(int argc, char **argv) {// ROS节点初始化ros::init(argc, argv, turtle_command_server);// 创建节点句柄ros::NodeHandle n;// 创建一个名为/turtle_command的server注册回调函数commandCallbackros::ServiceServer command_service n.advertiseService(/turtle_command, commandCallback);// 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10turtle_vel_pub n.advertisegeometry_msgs::Twist(/turtle1/cmd_vel, 10);// 循环等待回调函数ROS_INFO(Ready to receive turtle command.);// 设置循环的频率ros::Rate loop_rate(10);while(ros::ok()){// 查看一次回调函数队列ros::spinOnce();// 如果标志为true则发布速度指令if(pubCommand){geometry_msgs::Twist vel_msg;vel_msg.linear.x 0.5;vel_msg.angular.z 0.2;turtle_vel_pub.publish(vel_msg);}//按照循环频率延时loop_rate.sleep();}return 0; } 配置CMakeLists.txt nano ~/catkin_workspace/src/learning_service/CMakeLists.txt添加 add_executable(turtle_command_server src/turtle_command_server.cpp) target_link_libraries(turtle_command_server ${catkin_LIBRARIES})编译并运行 cd ~/catkin_workspace catkin_make# 新建一个终端 source ~/catkin_workspace/devel/setup.bash roscore # 新建一个终端 source ~/catkin_workspace/devel/setup.bash rosrun turtlesim turtlesim_node # 新建一个终端 source ~/catkin_workspace/devel/setup.bash rosrun learning_service turtle_command_server # 新建一个终端 source ~/catkin_workspace/devel/setup.bash rosservice call /turtle_command {}rqt_graphpython 创建并编写脚本 nano ~/catkin_workspace/src/learning_service/scripts/turtle_command_server.py#!/usr/bin/env python # -*- coding: utf-8 -*-######################################################################## #### Copyright 2020 GuYueHome (www.guyuehome.com). ### ######################################################################### 该例程将执行/turtle_command服务服务数据类型std_srvs/Triggerimport rospy import thread,time from geometry_msgs.msg import Twist from std_srvs.srv import Trigger, TriggerResponsepubCommand False; turtle_vel_pub rospy.Publisher(/turtle1/cmd_vel, Twist, queue_size10)def command_thread(): while True:if pubCommand:vel_msg Twist()vel_msg.linear.x 0.5vel_msg.angular.z 0.2turtle_vel_pub.publish(vel_msg)time.sleep(0.1)def commandCallback(req):global pubCommandpubCommand bool(1-pubCommand)# 显示请求数据rospy.loginfo(Publish turtle velocity command![%d], pubCommand)# 反馈数据return TriggerResponse(1, Change turtle command state!)def turtle_command_server():# ROS节点初始化rospy.init_node(turtle_command_server)# 创建一个名为/turtle_command的server注册回调函数commandCallbacks rospy.Service(/turtle_command, Trigger, commandCallback)# 循环等待回调函数print Ready to receive turtle command.thread.start_new_thread(command_thread, ())rospy.spin()if __name__ __main__:turtle_command_server()运行 sudo chmod x ~/catkin_workspace/src/learning_service/scripts/turtle_command_server.py# 新建一个终端 source ~/catkin_workspace/devel/setup.bash roscore # 新建一个终端 source ~/catkin_workspace/devel/setup.bash rosrun turtlesim turtlesim_node # 新建一个终端 source ~/catkin_workspace/devel/setup.bash rosrun learning_service turtle_command_server.py # 新建一个终端 source ~/catkin_workspace/devel/setup.bash rosservice call /turtle_command {}rqt_graph