Using the real Limo Robot

The goal is to make you familiar with the LIMO robot platform.

There are some Expert notes for setting up the Limo installation which will not be relevant to the "normal" operator and are only here for troubleshooting. Read ahead to focus on the main essentials:

1 Get to know your LIMO

• Check the manufacturer's webpage and read Sections 1.1-1.6 of the manual whilst inspecting the real robot and its components. (Unfortunately the app suggested in Section 1.8 of the manual does not exist in UK app stores.)

2 Setup

Get your robot and check it out

• Take the box and scan the QR code on it. Fill out the online form to check out the robot for your use. Remember to use the same form to check it back in when you are done!
• Keep the robot always on the floor to avoid it accidentally driving off a table!

Battery

• Ensure you insert the battery correctly (so that the ribbon is underneath it).

Power up

• Press and hold the power button for about 5 seconds (until it beeps) to turn the robot on.

Power down

• Press and hold the power button for about 5 seconds (until it beeps) to turn the robot off again.

IP address

The robot is connected wirelessly to the lab network (if it is not please ask a member of staff for details). To establish a connection with your LIMO, we need to find out its IP address. Open the terminal and type ip a using the robot's touchscreen keyboard (see next paragraph on how to switch it on). Note the inet address associated with the wlan0 device. Write this IP address down. You will need to repeat that procedure at the start of each session. It should be something like 10.82.0.XXX, where XXX is a number between 2 and 254. The IP address should stay always the same as long as you are using the same robot.

To enable the robot's touchscreen keyboard, first check if there is a small four-square icon on the desktop's top bar and if yes, select Show Onboard.

VNC connection (optional, not needed)

• Install a VNC viewer, e.g. from here: https://www.realvnc.com/en/connect/download/viewer/ and install it
• Connect to your robot, e.g. to IP 10.82.0.XXX (you have taken note of the IP address before) to have a more comfortable way to see the screen

This is entirely optional and not required.

Connect your computer to the robot using Zenoh

In your own computer's devcontainer, you connect the local ROS2 system to the robots as follows:

1. Make sure you are not running the simulation when connecting to the real robot! Stop it if you have to ([Ctrl-C])
2. start the bridge: zenoh-bridge-ros2dds -e tcp/10.82.0.XXX:8888 (you need to add your robot's IP here) and keep it running
3. run ros2 topic list -v in a different terminal and you should see all the robot topics. Check which topic names are different to the simulation and which are the same.

Basic operations

1. Now, let us use the graphical visualiser RVIZ to look at the robot and its sensor topics. Start by typing rviz2. Explore different sensor stream

2. Teleoperation. Leave the RVIZ running. In a new terminal start the keyboard teleoperation node ros2 run teleop_twist_keyboard teleop_twist_keyboard and drive the robot around using the keyboard. Have fun, but pay attention to other robots and your human fellows, though!

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Setup notes

update installation

• make some space: docker system prune -a and sudo apt-get purge "libre-office*"
• install docker compose: execute .devcontainer/on_limo/install-docker-compose.sh from limo_ros2 repo: https://raw.githubusercontent.com/LCAS/limo_ros2/humble/.devcontainer/on_limo/install-docker-compose.sh and run it as bash install-docker-compose.sh