Static Reconstruction with ZED
==============================

.. figure:: :ir_lfs:`<resources/isaac_ros_docs/repositories_and_packages/isaac_ros_nvblox/zed_example.gif>`
    :width: 600px
    :align: center

This tutorial demonstrates how to perform depth-camera based reconstruction
using a `ZED <https://www.stereolabs.com/docs/get-started-with-zed>`__ camera.

.. note::
   This tutorial requires a compatible ZED camera from
   the list available  :doc:`here </getting_started/hardware_setup/sensors/zed_setup>`.

Host System Setup
-----------------

The ROS 2 message delivery can be unreliable under high load
without some small modifications to the QoS profile (especially on
weaker machines). Before running this example, run one of the following:

To set the parameter temporarily, until reboot:

.. code:: bash

   sudo sysctl -w net.core.rmem_max=8388608 net.core.rmem_default=8388608

To set the parameter permanently, run:

.. code:: bash

   echo -e "net.core.rmem_max=8388608\nnet.core.rmem_default=8388608\n" | sudo tee /etc/sysctl.d/60-cyclonedds.conf

See
`DDS tuning <https://docs.ros.org/en/rolling/How-To-Guides/DDS-tuning.html>`__ for more details.

Installing the Dependencies
---------------------------

1. Complete steps 1 and 2 described in the
   :doc:`Nvblox Quickstart Guide </repositories_and_packages/isaac_ros_nvblox/isaac_ros_nvblox/index>`
   to set up your development environment and clone the required repositories.

2. Complete the :doc:`/getting_started/hardware_setup/sensors/zed_setup`
   to set up `ZED`.

Example with ZED Live Data
--------------------------

1. Complete the sections above.

2. Connect the ZED device to your machine using a USB 3 cable/port.

3. Run the ROS Docker container using the ``run_dev.sh`` script:

   .. code:: bash

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

4. Build and source the workspace:

   .. code:: bash

      cd /workspaces/isaac_ros-dev && \
        colcon build --symlink-install && \
        source install/setup.bash

5. At this point, you can check that the ZED camera is connected
   by running the ``ZED_Explorer``:

   .. code:: bash

      /usr/local/zed/tools/ZED_Explorer

6. If successful, run the launch file to spin up the example:

   .. code:: bash

      ros2 launch nvblox_examples_bringup zed_example.launch.py