webots_ros2/webots_ros2_universal_robot

• Universal Robot
• • Creation of the UR5e URDF file
  • • In order to reproduce a Xacro file that can generate this URDF file follow these steps:
    • Steps on the UniversalRobots files:
    • • The ur.urdf.xacro file:
      • The visual_parameters.yaml file:
      • The ur_macro.xacro file:
      • The ur.ros2_control.xacro file:
    • Steps on the robotiq files:
    • • The robotiq-3f-gripper_articulated_macro.xacro file:
      • The robotiq-3f-gripper_finger_articulated_macro.xacro file:

Universal Robot

This package provides an interface between ROS2 and the UR3e, UR5e and UR10e simulation models of the Universal Robots running in Webots.
It includes several simulations of these robots.

Documentation is available here.

Creation of the UR5e URDF file

The URDF file for the UR5e robot used in this package is a mix of the UR5e robot taken from UniversalRobots and the 3-fingers-gripper taken from robotiq.
Some adaptations have been made in the files from the two repositories.

In order to reproduce a Xacro file that can generate this URDF file follow these steps:

• Clone the repositories of UniversalRobots and robotiq in your package.
• Create your own Xacro file to combine the robot and the gripper and add the <webots> plugin tag:

<?xml version="1.0"?>
<robot name="UR5e" xmlns:xacro="http://wiki.ros.org/xacro">
    <!--
        Custom mix of ur5e robot and robotiq 3f gripper for Webots.
        Based on https://github.com/UniversalRobots/Universal_Robots_ROS2_Driver
        and https://github.com/ros-industrial/robotiq.
    -->

    <webots>
        <plugin type="webots_ros2_control::Ros2Control" />
    </webots>

    <!-- ur5e robot -->
    <xacro:include filename="$(find webots_ros2_universal_robot)/resource/Universal_Robots_ROS2_Driver/ur_description/urdf/ur.urdf.xacro" />

    <!-- robotiq 3f gripper -->
    <xacro:include filename="$(find webots_ros2_universal_robot)/resource/robotiq/robotiq_3f_gripper_visualization/cfg/robotiq-3f-gripper_articulated_macro.xacro" />
    <xacro:robotiq-3f-gripper_articulated prefix=""/>
</robot>

Steps on the UniversalRobots files:

The ur.urdf.xacro file:

• Define the joint_limit_params, kinematics_params, physical_params and visual_params default arguments with the path to their corresponding .yaml files.
• Update all the paths accordingly to your package.

The visual_parameters.yaml file:

• Update all the paths accordingly to your package.

The ur_macro.xacro file:

• Remove the 4 lines below <!-- Data files required by the UR driver -->.
• Replace the tag <xacro:ur_ros2_control.../> below <!-- ros2 control instance --> by:

<xacro:ur_ros2_control
    name="WebotsControl" prefix="${prefix}"
    initial_positions="${initial_positions}" />

• Update all the paths accordingly to your package.

The ur.ros2_control.xacro file:

• Remove script_filename output_recipe_filename input_recipe_filename tf_prefix hash_kinematics robot_ip from the <xacro:macro...> tag.
• Remove the <joint name="speed_scaling">, the <joint name="gpio">, the <joint name="resend_robot_program"> and the <joint name="system_interface"> tags.
• Remove all the <command_interface name="velocity">...</command_interface> tags and all the <param...>...</param> tags from the <command_interface name="position">...</command_interface> tags
• Replace the <hardware></hardware> tag by:

<hardware>
    <plugin>webots_ros2_control::Ros2ControlSystem</plugin>
</hardware>

• In order to also control the gripper, add after the <sensor name="tcp_fts_sensor">...</sensor> tag these tags:

<!-- ROBOTIQ 3F Gripper -->
<joint name="palm_finger_1_joint">
    <state_interface name="position"/>
    <command_interface name="position"/>
</joint>
<joint name="finger_1_joint_1">
    <state_interface name="position"/>
    <command_interface name="position"/>
</joint>
<joint name="finger_1_joint_2">
    <state_interface name="position"/>
    <command_interface name="position"/>
</joint>
<joint name="finger_1_joint_3">
    <state_interface name="position"/>
    <command_interface name="position"/>
</joint>
<joint name="palm_finger_2_joint">
    <state_interface name="position"/>
    <command_interface name="position"/>
</joint>
<joint name="finger_2_joint_1">
    <state_interface name="position"/>
    <command_interface name="position"/>
</joint>
<joint name="finger_2_joint_2">
    <state_interface name="position"/>
    <command_interface name="position"/>
</joint>
<joint name="finger_2_joint_3">
    <state_interface name="position"/>
    <command_interface name="position"/>
</joint>
<joint name="finger_middle_joint_1">
    <state_interface name="position"/>
    <command_interface name="position"/>
</joint>
<joint name="finger_middle_joint_2">
    <state_interface name="position"/>
    <command_interface name="position"/>
</joint>
<joint name="finger_middle_joint_3">
    <state_interface name="position"/>
    <command_interface name="position"/>
</joint>

Steps on the robotiq files:

The robotiq-3f-gripper_articulated_macro.xacro file:

• Remove the <link name="${prefix}tool0"/> tag and replace the <joint name="${prefix}palm_tool0" type="fixed">...</joint> tags by:

<joint name="${prefix}tool0_palm" type="fixed">
    <parent link="${prefix}tool0"/>
    <child link="${prefix}palm"/>
    <origin xyz="0 0 0.045" rpy="1.5708 0 0"/>
</joint>

• Update all the paths accordingly to your package.

The robotiq-3f-gripper_finger_articulated_macro.xacro file:

• Update all the paths accordingly to your package.