BusIT 2024-2025

Overview & Course materials

Week	Main Topic	Sub Topic(s)
Day 1	Intro	Introduction to Robotics, Introduction to ROS2
Day 2	Computer Vision	Computer Vision, Project
Day 3	LiDAR	LiDAR, Project
Day 4-5	Workshop & Project

Planning: link

Teams

Link

Development environment

Repository: https://github.com/PXLAIRobotics/ROS2JazzyDocker

Discord server

Invite link: https://discord.gg/Nnt9ps3h

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Day 1: Intro

Introduction

1. 01 - Introduction to the international BusIT week
2. 02 - Introduction to robotics

ROS

1. 01 - Introduction to ROS
2. 02 - ROS Concepts
3. 03 - ROS: Publisher Subscriber
4. 04 - Simulation Environments

Exercises

1. Start the gazebo sim

gz sim

...and start the Prius on Sonoma Raceway world.

2. Create a ROS bridge for the /cmd_vel topic

ros2 run ros_gz_bridge parameter_bridge /cmd_vel@geometry_msgs/msg/Twist@gz.msgs.Twist

3. Create a Teleop Node that allows you to control the Prius using keyboard inputs.

4. Always remember to rebuild and source each time you change anything:

clean_and_rebuild_ros2_workspace

If that does not work, you can do it manually:

colcon build
source install/setup.bash

5. Go nuts

Day 2: Computer Vision

OpenCV

1. 01 - An introduction to OpenCV

Exercises

1. Start the gazebo sim

gz sim

...and start the Prius on Sonoma Raceway world.

2. Create a ROS bridge for the /front_camera topic

ros2 run ros_gz_bridge parameter_bridge /front_camera@sensor_msgs/msg/Image@gz.msgs.Image

3. Create a vision_controller package:

cd ~/Projects/ros2_workspace/src
ros2 pkg create --build-type ament_python vision_controller --dependencies rclpy image_transport cv_bridge sensor_msgs std_msgs opencv2

5. Add the src/process_front_camera.py script

6. Always remember to rebuild and source each time you change anything:

clean_and_rebuild_ros2_workspace

If that does not work, you can do it manually:

colcon build
source install/setup.bash

7. Drive autonomously along the racetrack. Use the Example OpenCV code for inspiration.

Day 3: LiDAR

LiDAR

1. 02 - ROS: Laser rangefinders and ROS

Exercises

Day 4-5: Workshop & Project

Project info

It's recommended to use a Miro board for your business idea (https://miro.com/) to collaborate easily.

Project presentation tips

Technology path

You can show code examples, but limit it to the most relevant sections, i.e.:

• Usage of a canny edge detector
• Contour detection

Focus on visuals, i.e:

• Screenshots or video of the results of computer vision transformations
• Live demo of the car driving
• ...

Innovation path

• Use the AI Business model canvas as a starting point, but you can convert it into a presentation. Your choice. Make it a striking presentation!

Additional info

How to get an overview of all gazebo topics:

gz topic -l

Then you can use a ROS-Gazebo bridge for whatever topic you need.

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Troubleshooting

1.

ros2 run package_1 publisher output:

Package 'package_1' not found

Solution: You forgot to...

cd ~/Projects/ros2_workspace
colcon build
source install/setup.bash

2.

ros2 run package_1 subscriber output:

No executable found

Solution: You forgot to add subscriber to setup.py.

3.

colcon build output:

Summary: 0 packages finished [0.97s] 1 package failed: package_1 1 package aborted: example_package 1 package had stderr output: package_1 Command '['/usr/bin/python3', '-c', 'import sys;from contextlib import suppress;exec("with suppress(ImportError): from setuptools.extern.packaging.specifiers import SpecifierSet");exec("with suppress(ImportError): from packaging.specifiers import SpecifierSet");from distutils.core import run_setup;dist = run_setup( 'setup.py', script_args=('--dry-run',), stop_after='config');skip_keys = ('cmdclass', 'distclass', 'ext_modules', 'metadata');data = { key: value for key, value in dist.dict.items() if ( not key.startswith('_') and not callable(value) and key not in skip_keys and key not in dist.display_option_names )};data['metadata'] = { k: v for k, v in dist.metadata.dict.items() if k not in ('license_files', 'provides_extras')};sys.stdout.buffer.write(repr(data).encode('utf-8'))']' returned non-zero exit status 1.

Solution: You forgot a comma in your setup.py file

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Increasing Docker container performance (on Windows)

1.

Create a .wslconfig file in this location: C:\Users\<UserName>\.wslconfig

2.

Open the created .wslconfig file (with Notepad or VSCode), change your preferred memory usage for the container and number of logical processors:

Note

The default settings for WSL are:

• Memory: 50% of total memory on Windows.
• Processors: The same number of logical processors on Windows.

So to increase performance you want to set this to the maximum number of logical processors and more than 50% of the memory on your host device, otherwise the container will get less resources than before.

Source (and more settings)

[wsl2]
memory=16GB
processors=8

3.

Shutdown WSL in a terminal window:

wsl --shutdown

4.

Restart Docker desktop.

5.

Start the container again.

6.

You can check if it works by entering docker stats in a terminal window.

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Additional resources

• ROS2 (Jazzy): https://docs.ros.org/en/jazzy/Tutorials.html
• Gazebo: https://gazebosim.org/docs/harmonic/tutorials/
• Gazebo x ROS2: https://github.com/gazebosim/ros_gz/tree/ros2/ros_gz_bridge