ROS笔记-01 install和helloworld.txt

1. Ubuntu install of ROS Indigo<-- LTS (Long Term Service)
	http://wiki.ros.org/indigo/Installation/Ubuntu

2. HelloWorld 
	http://3.1415926.science/ros/2015/06/15/ROS%E6%91%B8%E7%B4%A2(3)%E4%B9%8BHelloWorld/
	
		workspace_folder/        -- WORKSPACE, provided by yourself
			build/       					 -- provided by catkin, $ catkin_make
			devel/       					 -- provided by catkin, $ catkin_make
			src/                   -- SOURCE SPACE, provided by yourself
				CMakeLists.txt       -- 'Toplevel' CMake file, provided by catkin, $ catkin_init_workspace
				package_1/
				  CMakeLists.txt     -- CMakeLists.txt file for package_1
				  package.xml        -- Package manifest for package_1
				...
				package_n/
				  CMakeLists.txt     -- CMakeLists.txt file for package_n
				  package.xml        -- Package manifest for package_n
				  
				  
		
			1). 初始化项目目录 创建工作空间目录workspace/src后进入并执行命令以初始化此项目目录
				catkin_init_workspace
			2). 编译工作空间 先切换到workspace目录
				catkin_make
			3). 配置工作空间环境
				source devel/setup.bash
					环境变量设置检查
				echo $ROS_PACKAGE_PATH
					若返回类似这样 /root/dev/workspace/src:/opt/ros/indigo/share:/opt/ros/indigo/stacks, 则环境变量配置成功
			4). 创建包
				cd src
				catkin_create_pkg pachage_1 std_msgs rospy roscpp
				
				Created file pachage_1/CMakeLists.txt
				Created file pachage_1/package.xml
				Created folder pachage_1/include/pachage_1
				Created folder pachage_1/src										        -- your source file



		a. 两种创建ROS程序包的方式介绍
			catkin包是ROS的一个官方的编译构建系统，是原本的ROS的编译构建系统rosbuild的后继者
			rosbuild包(不使用)
		b. 过程(学习如何开发catkin工程)
			b.1 参照上文完成工程源码编写，熟悉工程结果，了解大致原理
				cmake CMakeLists.txt
				make
			b.2 运行 ROS 节点前需要开启 ros_master
				roscore
			b.3 运行上述创建的两个节点
				./listener 
				./talker