Tutorial: Generate an Occupancy Map for Navigation
==================================================

This tutorial will enable you to create a 2D occupancy map of your environment.
This map can the be used for autonomous navigation.

Instructions
------------

1. SSH into the robot (:ref:`instructions<nova-carter-ssh-setup>`).

2. Make sure you have successfully connected the PS5 joystick to the robot
   (:ref:`instructions<nova-carter-joystick-setup>`).

3. Build/install the required packages:

.. run_ros_app::
    :repo_setup: <nova-carter-dev-setup>
    :repo: nova_carter
    :image: isaac/nova_carter_bringup:release_3.2-aarch64
    :package: nova_carter_bringup
    :app: lidar_mapping.launch.py
    :skip_packages: isaac_ros_ess_models_install:isaac_ros_peoplesemseg_models_install

4. Make sure you complete :ref:`visualization-setup-carter`.
   Open Foxglove Studio on your remote machine,
   open the ``nova_carter_navigation.json`` layout file downloaded in the previous step.

   You should already see a visualization of the part of the map that is in close proximity to the
   robot.

.. figure::
    :ir_lfs:`<resources/isaac_ros_docs/robots/nova_carter/foxglove_mapping.png>`
    :width: 800px
    :alt: foxglove_mapping
    :align: center

5. To map your entire environment move the robot around using the joystick. You should be able to
   see the map visualization in Foxglove expand in real-time as you are moving the robot around.

6. To store the map open a new terminal, SSH into the robot, and attach to the
   docker container that's running the lidar mapping application. This depends on
   what approach you chose above to build/install the app.

.. tabs::

    .. tab:: Docker Image

        Get the name of the docker container by running

        .. code:: bash

          docker ps

        Then attach to the docker container with the following command. Make
        sure to replace ``<name-of-docker-container>`` with the name found
        above.

        .. code:: bash

          docker exec -it <name-of-docker-container> /bin/bash

    .. tab:: Binary Package

        Isaac ROS development docker container using the ``run_dev.sh`` script:

        .. code:: bash

          cd $ISAAC_ROS_WS/src/isaac_ros_common && \
            ./scripts/run_dev.sh

    .. tab:: Build from Source

        Isaac ROS development docker container using the ``run_dev.sh`` script:

        .. code:: bash

          cd $ISAAC_ROS_WS/src/isaac_ros_common && \
            ./scripts/run_dev.sh


7. Next run the below command to save the map ``.png`` and ``.yaml`` file:

   This ``.yaml`` file can be used as the input map in the
   :doc:`navigation tutorial</reference_workflows/isaac_perceptor/tutorials_on_carter/demo_navigation>`.

.. code:: bash

    source /opt/ros/humble/setup.bash
    cd /workspaces/isaac_ros-dev
    ros2 run nav2_map_server map_saver_cli --fmt png -f <path/to/my/map>

.. note::

   Please make sure to replace ``<path/to/my/map>`` with the path where the map
   should be stored. To keep the map when the docker container is
   stopped, it is recommended to use a path that is mounted to the docker
   container, for example ``/tmp/my_map.png``. If you are running this example
   with the pre-built docker image, then no suitable path is mounted. In this
   case you can use ``docker cp <name-of-docker-container>:<path/to/my/map> .``
   to copy the map out of the container.