../_images/tiagopro-icon.png ../_images/tiago-icon.png ../_images/triago-icon.png ../_images/mobile-bases-icon.png

How to use the dockstation#

🏁 Goal of this tutorial

By the end of this tutorial, you will know how to make the robot autonomously dock and undock using the PAL dockstation.

Pre-requisites#

Caution

This tutorial requires the robot to be equipped with a dockstation and that the dockstation is properly powered.

Dock the robot using RViz#

The easiest way to dock the robot is by using the RViz GUI. This requires that you first establish the communication with the robot as explained in Set up ROS 2 communication with the robot.

Then, in the same terminal that is connected to the robot, you can start RViz with the command:

rviz2 -d /opt/pal/$PAL_DISTRO/share/<ROBOT>_2dnav/config/rviz/navigation.rviz

Attention

Make sure to replace the <ROBOT> placeholder with the name of your robot (e.g. tiago, omni_base, tiago_pro, etc.).

Otherwise, if you want to use the simulation, you can use the following command:

source /opt/pal/${PAL_DISTRO}/setup.bash
ros2 launch <robot>_gazebo <robot>_gazebo.launch.py navigation:=True docking:=True world_name:=pal_office_w_docks

This starts the simulation in a virtual environment with several dockstations available.

../_images/pal_office_w_docks.svg

Once RViz is running and is connected to the robot or to the simulation, you can dock it by following these steps:

  1. If not already available, load the PAL Navigation 2 panel in RViz

../_images/pal_nav2_panel1.svg

  1. Go to the Docking tab in the PAL Navigation 2 panel

../_images/docking_manager_rviz_interface.svg

  1. Place the robot in front of the dockstation, as shown in the image below:

Staging Pose for Dock Detection

Staging Pose for Dock Detection#

  1. Click on the Dock button in the PAL Navigation 2 panel

This will send a new Action Goal to the /dock_robot Server, which will trigger the Docking detection system and the robot will autonomously navigate to the dockstation and dock itself.

Undock the robot using RViz#

The easiest way to undock the robot is by using the RViz GUI through the PAL Navigation 2 RViz panel. To achieve this, the Docking tab in the PAL Navigation 2 panel provides an Undock button that will send a new Action Goal to the /undock_robot Server, which will trigger the undocking maneuver.

Dock the robot using ROS 2 Actions#

Alternatively, to trigger the Dock, one can use the /dock_robot Action. By sending an Action Goal to this Server it will make the robot detect a dock and perform the docking maneuver.

Please, refer to the following examples for executing docking:

ros2 action send_goal /dock_robot opennav_docking_msgs/action/DockRobot "use_dock_id: false
dock_id: ''
dock_pose:
  header:
    stamp:
      sec: 0
      nanosec: 0
    frame_id: 'map'
  pose:
    position:
      x: 0.0
      y: 0.0
      z: 0.0
    orientation:
      x: 0.0
      y: 0.0
      z: 0.0
      w: 1.0
dock_type: 'pal_charging_dock'
max_staging_time: 1000.0
navigate_to_staging_pose: false"

Undock the robot using ROS 2 Actions#

Similarly, to trigger the Undock, one can use the /undock_robot Action. By sending an Action Goal to this Server it will make the robot perform the undocking maneuver.

ros2 action send_goal /undock_robot opennav_docking_msgs/action/UndockRobot "dock_type: 'pal_charging_dock'
max_undocking_time: 30.0"

Next steps#