HOME

---

ROS launch files

For bigger projects it should be not easy to open up differnt terminals to different nodes and ROS process So ROS had provided a solution known as

Launch files

launch files will run roscore when called and even you can run multiple ros lauch files in a single extention lauch files are generlly in end in ‘my_xxx.launch’

Lauch files are in XML format

XML tags in launch files

• launch :-parent tag and main tag

<?xml version="1.0" encoding="UTF-8"?>
<launch>
  <! other between these-->
</launch>

• node
  • arg

  <?xml version="1.0" encoding="UTF-8"?>
  <launch>
    <node name ="mynodexyz" pkg="rosbasics" type="pubsub.py">
      <arg name="xyz" default="sfs" value="xxx"/>
    </node>
  </launch>
  

Let’s create Launch for our projects

• create a folder named as ‘launch’ inside rosbasics folder all your .launch files must be in this Folder
• Create file named Myfirst.launch

Myfirst.launch

   <?xml version="1.0" encoding="UTF-8"?>
   <launch>
     <node name ="turtle1" pkg="turtlesim" type="turtlesim_node"/>
     <node name ="controller" pkg="rosbasics" type="pubsub.py" output="screen"/>
   </launch>

Lets RUN it

roslaunch rosbasics Myfirst.launch

---

Back to:Chapter 3

Next to:Chapter 5