moveit_planning_execution.xml

<?xml version="1.0"?>
<launch>
  <arg name="robot_ip" value="127.0.0.1" />

  <group>
    <include file="$(find ur5_moveit_config)/launch/ur5_moveit_planning_execution.launch">
      <arg name="sim" value="false" />
    </include>
  </group>

  <group ns="sim">
    <include file="$(find ur5_moveit_config)/launch/ur5_moveit_planning_execution.launch">
      <arg name="sim" value="true" />
    </include>
  </group>

</launch>