Combining URDF-files with tf (static_transform)

edit

Hello, I'm struggling with combining different urdf files (robots). I had some problems when I added everything in one urdf file ( http://answers.gazebosim.org/question... ) so I tried another attempt. I split it up in two different urdf files and made a static transform between the two links.

This is my launch file

    <?xml version="1.0" ?>
<launch>
  <!-- LAUNCH INTERFACE -->

  <!-- The robot name is required for gazebo to spawn a model. -->
  <arg name="robot_name" default="kuka-lwr-gripper"/>

  <!-- The recommended way of specifying the URDF file is to pass it in
       directly. -->
  <arg name="robot_path" default="$(find kuka-lwr-gripper)/robot"/> 
  <arg name="robot_urdf_file" default="$(arg robot_path)/$(arg robot_name)_standalone.urdf.xacro" />
  <arg name="gripper_urdf_file" default="$(arg robot_path)/simple_gripper/simple_gripper_model.urdf.xacro" />

  <!-- <arg name="controllers" default="joint_controllers"/> -->
  <arg name="controllers" default="joint_controllers"/>
  <arg name="t1_limits" default="false"/>

  <arg name="rviz_config" default="$(find lwr_launch)/launch/rviz/rviz_config.rviz"/>
  <arg name="rviz_bringup" default="true"/> <!--If false, do not launch rviz-->

  <arg name="hw_interface_file" default="$(find kuka-lwr-gripper)/config/hw_interface.yaml"/>
  <arg name="controller_config_file" default="$(find kuka-lwr-gripper)/config/controllers.yaml"/>
  <arg name="gazebo_world_file" default="$(find kuka-lwr-gripper)/worlds/simple_environment.world"/>
  <arg name="t1_limits_file" default="$(find kuka-lwr-gripper)/config/t1_joint_limits.yaml"/>
  <arg name="GAZEBO_GUI" default="true"/>

  <!-- gripper parameters -->
  <arg name="gripper_controller_config_file" default="$(find kuka-lwr-gripper)/config/gripper_controllers.yaml"/>

  <!-- ROBOT -->
  <group ns="lwr">
    <param name="robot_description" command="$(find xacro)/xacro $(arg robot_urdf_file)"/>
    <node name="robot_state_publisher" pkg="robot_state_publisher" type="robot_state_publisher"/>
  </group> 


  <!-- GRIPPER -->
  <group ns="my_gripper">
    <param name="robot_description" command="$(find xacro)/xacro $(arg gripper_urdf_file)"/>

    <node name="my_tp_lwr" pkg="tf" type="static_transform_publisher" args="0 0 0.01 0 0 0 lwr_7_link base_link 100"/>

    <node name="robot_state_publisher" pkg="robot_state_publisher" type="robot_state_publisher"/>
  </group> 


  <!-- GAZEBO -->
  <node name="spawn_urdf1" pkg="gazebo_ros" type="spawn_model" args="-param /lwr/robot_description -urdf -model $(arg robot_name)" respawn="false" output="screen" />
  <node name="spawn_urdf2" pkg="gazebo_ros" type="spawn_model" args="-param /my_gripper/robot_description -urdf -model my_gripper1" respawn="false" output="screen" />

  <!-- enable/disable gui at will, the rviz listens to the simulation -->
  <include file="$(find gazebo_ros)/launch/empty_world.launch">
    <arg name="world_name" value="$(arg gazebo_world_file)"/>
    <arg name="paused" value="false"/>
    <arg name="use_sim_time" value="true"/>
    <arg name="gui" value="$(arg GAZEBO_GUI)"/>
    <arg name="headless" value="false"/>
    <arg name="debug" value="false"/>
  </include>

  <!-- Load updated joint limits (override information from single_lwr_moveit) to respect T1 mode limits -->
  <group if="$(arg t1_limits)" ns="robot_description_planning">
    <rosparam command="load" file="$(arg t1_limits_file)"/>
  </group>

  <!-- load robotHW configurations to rosparam server -->
  <rosparam command="load" file="$(arg hw_interface_file)"/> 

  <!-- load all controller configurations to rosparam server -->
  <rosparam command="load" file="$(arg controller_config_file)" /> 

  <!-- load the gripper controller configuration to rosparam server -->
  <rosparam command="load" file="$(arg gripper_controller_config_file)"/> 

  <!-- real robot and controllers -->
  <group ns="lwr">
     <!-- spawn only desired controllers in current namespace --> 
     <node name="controller_spawner_js" pkg="controller_manager" type="spawner" respawn="false" output="screen" args="kuka_joint_state_controller"/>
     <node name="controller_spawner" pkg="controller_manager" type="spawner" respawn="false" output="screen" args="$(arg controllers)"/>  
  </group>

  <group ns="my_gripper">
     <!-- <param name="robot_description" command="$(find xacro)/xacro.py $(arg robot_urdf_file)"/> -->
     <node name="controller_spawner" pkg="controller_manager" type="spawner" respawn="false" output="screen" args="left_finger_joint_position_controller right_finger_joint_position_controller joint_state_controller"/> 
  </group>

  <!-- LAUNCH RVIZ -->

  <node name="lwr_rviz" pkg="rviz ...