.. _tutorial_sitl:

Software-In-The-Loop Simulation
====================================

**Note: This tutorial is applicable for all Kerloud VTOL products.**

We provide the Software-In-The-Loop (SITL) simulation environment for our customers to validate their
onboard application software before real flights.

Due to environment dependencies, the SITL simulation can only be run on an Intel-64 PC with Ubuntu 18.04 instead of the onboard computer.
The minimum hardware requirements are: an Intel i7 processor and 8GB RAM memory. 

Environment Prerequisites
---------------------------

The required environment is Ubuntu 18.04 with ROS melodic and Gazebo 9 engine, and a complete PX4 development toolchain should be setup as well.
Users can refer to instructions in http://cloudkernel-tech.gitee.io/kerloud_mini/en/ADVANCEDDEV.html and utilize the convenience scripts for quick setup.
The setup commands are:

::

        cd Tools/setup/custom
        bash ubuntu.sh
        bash ubuntu_sim_ros_melodic.sh

Invited customers will join our maintained repository SITL-space in https://gitee.com/cloudkernel-tech/sitl_space_vtol.
Please keep updated since the repository will be upgraded regularly.


How to Use
-------------

The SITL simulation can be brought up simply by running:

::

        cd <sitl-space directory> \
        && bash sitl_run.sh $PWD/bin/px4 none gazebo standard_vtol

Hopefully the gazebo 9 will show up with a virtual VTOL vehicle as given below:

.. image:: ../img/sitl_snap.png
   :height: 450 px
   :width: 750 px
   :scale: 100 %
   :align: center

Users can then start the Qgroundcontrol station and their customized ROS nodes for application development.