Hello, I have created a launch file that can successfully launch and control two UR5 robots. But it seems that the TF of both the robots is not published separately, they are published as one. I need two to have two unique TF's for both the robots. I dont know where I have made mistake.

here is my launch file

<?xml version="1.0"?>
<launch>
  <param name="red_box_path" type="str" value="$(find ur5_notebook)/urdf/red_box.urdf"/>
  <arg name="robot_name"/>
  <!-- <arg name="init_pose"/> -->
  <arg name="limited" default="true"/>
  <arg name="paused" default="false"/>
  <arg name="gui" default="true"/>
  <arg name="debug" default="false" />
  <arg name="sim" default="true" />

  <!-- startup simulated world -->
  <include file="$(find gazebo_ros)/launch/empty_world.launch">
    <arg name="world_name" default="worlds/empty.world"/>
    <arg name="paused" value="$(arg paused)"/>
    <arg name="gui" value="$(arg gui)"/>
  </include>

  <node name="bin" pkg="gazebo_ros" type="spawn_model" args="-file $(find ur5_notebook)/urdf/bin.urdf -urdf -model bin -y 0.8 -x -0.5 -z 0.05" />
  <!-- <node name="bin2" pkg="gazebo_ros" type="spawn_model" args="-file $(find ur5_notebook)/urdf/bin.urdf -urdf -model bin -y -0.8 -x 0.5 -z 0.05" /> -->

  <!-- spawn the conveyor_belt in gazebo -->
  <node name="spawn_conveyor_belt" pkg="gazebo_ros" type="spawn_model" args="-file $(find ur5_notebook)/urdf/conveyor_belt.urdf -urdf -model conveyor_belt" />
  <!-- spawn the conveyor_belt in gazebo -->

  <!-- the red blocks spawner node -->

  <node name="blocks_spawner" pkg="ur5_notebook" type="blocks_spawner" output="screen" />
  <!-- <node name="blocks_spawner2" pkg="ur5_notebook" type="blocks_spawner2" output="screen" /> -->

  <node name="blocks_poses_publisher" pkg="ur5_notebook" type="blocks_poses_publisher" output="screen" />

  <group ns="robot1">
    <param name="tf_prefix" value="robot1_tf" />
      <include file="$(find ur_gazebo)/launch/ur5.launch">
        <arg name="init_pose" value="-z 0.2 -y 0.7"/>
        <arg name="robot_name" value="robot1"/>
        <!-- <node name="spawn_gazebo_model" pkg="gazebo_ros" type="spawn_model" args="-urdf -param robot_description -model $(arg robot_name)-x 0.5 -z 0.2 -y 1.1" respawn="false" output="screen" /> -->
      </include>

      <include file="$(find ur5_moveit_config)/launch/move_group.launch">
        <arg name="limited" default="$(arg limited)"/>
        <arg name="debug" default="$(arg debug)" />
      </include>

      <!-- <node name="ur5_vision" pkg="ur5_notebook" type="ur5_vision.py" output="screen" />
      <node name="ur5_gripper" pkg="ur5_notebook" type="ur5_gripper.py" output="screen"/> -->

      <remap if="$(arg sim)" from="follow_joint_trajectory" to="arm_controller/follow_joint_trajectory"/>

      <node name="ur5_vision_robot1" pkg="ur5_notebook" type="ur5_vision_robot1.py" output="screen" />
  <!-- <node name="ur5_mp_robot1" pkg="ur5_notebook" type="ur5_mp_robot1.py" output="screen" /> -->
      <node name="ur5_gripper_robot1" pkg="ur5_notebook" type="ur5_gripper_robot1.py" output="screen"/>



  </group>

  <group ns="robot2">
    <param name="tf_prefix" value="robot2_tf" />
      <include file="$(find ur_gazebo)/launch/ur5_r2.launch">
        <arg name="init_pose" value="-z 0.2 -y -0.70"/>
        <arg name="robot_name" value="robot2"/>
        <!-- <node name="spawn_gazebo_model" pkg="gazebo_ros" type="spawn_model" args="-urdf -param robot_description -model $(arg robot_name)-x 0.5 -z 0.2 -y 1.1" respawn="false" output="screen" /> -->

      </include>
      <!-- <node name="blocks_poses_publisher" pkg="ur5_notebook" type="blocks_poses_publisher" output="screen" /> -->
      <!-- <node name="ur5_mp" pkg="ur5_notebook" type="ur5_mp.py" output="screen" /> -->

      <remap if="$(arg sim)" from="follow_joint_trajectory" to="arm_controller/follow_joint_trajectory"/>

      <include file="$(find ur5_r2_moveit_config)/launch/move_group.launch">
        <arg name="limited" default="$(arg limited)"/>
        <arg name="debug" default="$(arg debug)" />
      </include>
      <!-- <node name="ur5_vision" pkg="ur5_notebook" type="ur5_vision.py" output="screen" />
      <node name="ur5_gripper" pkg="ur5_notebook" type="ur5_gripper.py" output="screen"/> -->


      <node name="ur5_vision" pkg="ur5_notebook" type="ur5_vision.py" output="screen" />
      <node name="ur5_r2_gripper" pkg="ur5_notebook" type="ur5_gripper.py" output="screen"/>
    <!-- Remap follow_joint_trajectory -->
  </group>
<!-- 
  <node name="ur5_mp" pkg="ur5_notebook" type="ur5_mp.py" output="screen" />
  <node name="ur5_mp_robot1" pkg="ur5_notebook" type="ur5_mp_robot1.py" output="screen" /> -->



  <!-- for ros control to be used with scara robot -->
  <!--   <param name="/scara_robot_left/robot_description" textfile="$(find two_scara_collaboration)/urdf/scara_robot_left.urdf" />-->

<!-- spawn the red_box in gazebo -->
<!-- node name="spawn_red_box" pkg="gazebo_ros" type="spawn_model" args="-file $(find ur5_notebook)/urdf/red_box.urdf -urdf -model red_box"/ -->

</launch>

I get two robots simulated in Gazebo perfectly but when I do rosrun rqt_tf_tree rqt_tf_tree I see that the tf for each robot are broadcasted for in the same tree with the parent frame as world. And even Rviz cannot visualize two robots because of the TF being mixed for both the robots.