1.一個簡單的launch檔案

//在catkin_ws/src/下建立一個包，單獨存放launch 檔案
cd catkin_ws/src
catkin_create_pkg my_launch
//回到catkin_ws目錄下
catkin_make

在包 my_launch 裡建立一個turtle.launch檔案，寫入下面的內容：

<launch>
  <node pkg="turtlesim" name="my_turtle" type="turtlesim_node" />
  <node pkg="turtlesim" name="keyboard"  type="turtle_teleop_key" />
</launch>
 

第二行的意思是要開啟pkg="turtlesim"包下的type="turtlesim_node"節點，併為節點取新名字為my_turtle。

//呼叫launch檔案
roslaunch my_package turtle.launch
//列印正在執行的節點
rosnode list

2.稍微複雜的launch檔案

在my_launch包裡建立一個turtlesim_advertise.launch檔案，寫入以下內容：

<launch>
  <include file="$(find my_launch)/turtle.launch"/>
  <node pkg="my_pkg" name="publisher" type ="publisher_Node" required="true" output="screen" />
  <node pkg="my_pkg" name="subscriber" type ="subscriber_Node" output="screen" respawn="true">
  </node>
</launch>

執行turtle_advertise.launch

roslaunch my_launch turtle_advertise.launch