How to use the UI and Eel together

Boot stuff

1. Start the Eel Raspberry PI.
2. Start a computer with Ubuntu installed.

Connection

Ethernet

1. Make sure you have a ethernet cable connected between the two.
2. Open Wired network settings on your computer:
   1. Top right corner.
   2. Click arrow.
   3. Click Settings.
   4. Click Network.
   5. Under Wired, click cog wheel.
3. Go to IPv4 tab.
4. Select Manual under IPv4 Method.
5. In the first row under Addresses, enter:
   • Address: 192.168.0.100
   • Netmask: 255.255.255.0
6. Click Apply and close the Network settings dialog.
7. Open a terminal:
   • Use for example Tabby, either from the Favorites panel to the left, or
   • by searching for Tabby after pressing the Windows button on your keyboard.
8. Type ssh eel and press enter.
9. If you get something like

   ubuntu@ubuntu >

   you’re good. If you get anything else, I can’t help you :)

Start applications

You will need to have three terminals running, which is why it’s good to use Tabby, since you can see them all at once.

We will refer to the three terminals as:

• Remote to RPi 1 (the one which you just connected to over SSH).
• Remote to RPi 2 (another SSH session just like the one above, which will be running ROS web bridge, so that the user interace can communicate with ROS).
• Ground control (which will be running the user interface).

Do this

1. In the Remote to RPi 1 terminal (which you just setup in the previous section), do the following:
   1. cd eel
   2. git checkout main
   3. git pull
   4. source source_me.sh
   5. make build-sym
   6. make start-pid-rudder
   7. You should now see some output saying that a few nodes have started. If you get any errors, I can’t help you :)
2. In another terminal, let’s say Remote to RPi 2, do the following:
   1. ssh eel
   2. cd eel/docker
   3. dc up -d
   4. dc logs -f
   5. You should see Docker starting up and then something like Rosbridge WebSocket server started....
3. In the third terminal, let’s say Ground control, do the following:
   1. cd ~/code/ground-control
   2. git checkout main
   3. git pull
   4. make setup
   5. make dev
   6. You should see something like started server on....

At this point (assuming no errors), everything should be up and running, so you can start sending commands from the web user interface.

Use the web user interface

1. Open a web browser.
2. Navigate to http://localhost:3000.
3. Select “Go to ROS Bridge”
4. If there are no backends to select, then click “Add backend”.
   1. Name -> E. g. “Ethernet”.
   2. Address -> 192.168.0.101.
   3. Click “Add backend”.
5. Now that there is a backend to select, click “Use backend”.

Shut down

When you’re done testing stuff, follow these steps to shut everything down properly:

1. In the Ground control terminal, press Ctrl C
2. In the Remote to RPi 1 terminal, press Ctrl C
3. In the Remote to RPi 2 terminal, press Ctrl C
   1. Then dc down
   2. Then sudo shutdown -h now
4. Kill the power to the Eel.
5. Shut down your computer.