# Raspberry Pi 4B Setup

This guide outlines the process of setting up a Raspberry Pi onboard companion computer without the need for a mouse or keyboard, using Ubuntu 20.04 Server Image.

#### Flashing OS on the Board

1. **Install rpi-imager**
   * Run `sudo apt install rpi-imager` to install the Raspberry Pi Imager.
   * Insert the microSD card into your computer.
2. **Choose OS and Storage**
   * Open Raspberry Pi Imager and select "Choose OS".
   * Navigate to the Ubuntu 20.04 Server image.
   * Select your microSD card under "Choose Storage".
3. **Configure Settings**
   * Click on the settings icon.
   * Enable "Enable SSH".
   * Set a username and password (e.g., "pi").
   * Configure wireless LAN to connect to your Wi-Fi network.
4. **Write OS to microSD**
   * Click "Write" to write the OS to the microSD card.
5. **Boot the Board**
   * Insert the microSD card into the board.
   * Check the LED status to confirm booting from the card.

#### Setting up Ubuntu Server Image for ARIITK

1. **Basic Linux Setup**

   ```bash
   sudo apt-get update
   sudo apt-get upgrade
   timedatectl set-local-rtc 1 --adjust-system-clock
   sudo apt-get install git
   ```
2. **ROS Setup**

   ```bash
   # Setup sources.list
   sudo sh -c 'echo "deb http://packages.ros.org/ros/ubuntu $(lsb_release -sc) main" > /etc/apt/sources.list.d/ros-latest.list'

   # Setup keys
   sudo apt install curl
   curl -s https://raw.githubusercontent.com/ros/rosdistro/master/ros.asc | sudo apt-key add -

   # Installation
   sudo apt update
   sudo apt install ros-noetic-base

   # Initialize rosdep
   sudo apt install python3-rosdep
   sudo rosdep init
   rosdep update

   # Setup environment
   echo "source /opt/ros/noetic/setup.bash" >> ~/.bashrc
   source ~/.bashrc

   # Fulfill dependencies
   sudo apt install python3-rosinstall python3-rosinstall-generator python3-wstool build-essential
   ```
3. **MAVROS Setup**

   <pre class="language-bash"><code class="lang-bash"># install some dependencies
   sudo apt install python3-rosinstall python3-rosinstall-generator python3-wstool build-essential

   # install MAVROS
   sudo apt-get install ros-noetic-mavros ros-noetic-mavros-extras

   cd ~/

   wget https://raw.githubusercontent.com/mavlink/mavros/master/mavros/scripts/install_geographiclib_datasets.sh
   sudo chmod a+x install_geographiclib_datasets.sh
   sudo ./install_geographiclib_datasets.sh

   # Install catkin tools
   sudo apt-get install python3-catkin-tools

   # Updating MAVProxy and pymavlink (new versions released now and then)
   sudo pip install --upgrade pymavlink MAVProxy

   #Setup MAVROS to begin communication
   cd ~/

   # Setup MAVROS workspace
   mkdir -p ~/ardupilot_ws/src
   cd ~/ardupilot_ws
   catkin init

   # Create launch file for MAVROS
   cd src
   mkdir launch
   cd launch
   roscp mavros apm.launch apm.launch
   sudo gedit apm.launch #opens a text editor, follow the next command (you can also do it using any other editor of your choice, for eg. by using 'code .' commmand)

   #To proxy to a Ground Control Station like QGC or Mission Planner on ground we just need to modify the first line to &#x3C;arg name="fcu_url" default="udp://:{ground-port}@{ground-hostname}" />. save you file and launch it with-
   <strong>cd ~/ardupilot_ws/src/launch
   </strong>roslaunch apm.launch

   </code></pre>
4. **QGC Setup**

   To configure QGroundControl for communication with MAVROS:

   1. **Open QGroundControl**
      * Launch QGroundControl on your ground station device.
   2. **Configure UDP Settings**
      * Navigate to 'Application Settings'.
      * Go to the 'Comm Links' tab.
      * Click 'Add' in the options menu.
      * Select 'Type' as 'UDP'.
      * Enter the{ground-port} in "Port" and {ground-hostname} in "Server Addresses (optional)"
   3. **Connect**
      * Click "OK" to save the settings.
      * Click on the "Connect" tab to establish the connection from side menu

   Ensure that your onboard companion computer and ground station are connected to the same LAN setup via a router for proper communication.

**Ensure both the board and the ground station are connected to the same LAN setup for the proxy to work.**