Learning Experience (LX): Collision Checker

About these activities

As part of this learning experience, you will write your very own collision checker. While this checker will only function in-simulation, it should give you a good idea of the complexity associated with detecting collisions in the real world.

The boilerplate code contained in this folder is a fully functional (albeit wrong) solution. Currently, the solution submits random guesses as to whether the robot collides with the environment or not. You can try to evaluate right away to see how it works.

Note: This is a code-only exercise: you don't need the Duckiebot.

This learning experience is provided by the Duckietown team. Visit us at the Duckietown Website for more learning materials, documentation, and demos.

For guided setup instructions, lecture content, and more related to this LX, see the Self Driving Cars with Duckietown course on EdX.

Grading challenge

Your submissions will be sent to two different challenges:

• lx22-collision-check-vali is the validation challenge. You will be able to see the score and other output.
• lx22-collision-check-test is the testing challenge. You will not be able to see the scores.

Instructions

NOTE: All commands below are intended to be executed from the root directory of this exercise (i.e., the directory containing this README).

1. Make sure your exercise is up-to-date

Update your exercise definition and instructions,

git pull upstream mooc2022

NOTE: to pull from upstream, you need to have completed the instructions in the duckietown-lx repository README to fork this repository.

2. Make sure your system is up-to-date

• 💻 Always make sure your Duckietown Shell is updated to the latest version. See installation instructions

• 💻 Update the shell commands: dts update

• 💻 Update your laptop/desktop: dts desktop update

3. Work on the exercise

Launch the code editor

Open the code editor by running the following command,

dts code editor

Wait for a URL to appear on the terminal, then click on it or copy-paste it in the address bar of your browser to access the code editor. The first thing you will see in the code editor is this same document, you can continue there.

Walkthrough of notebooks

NOTE: You should be reading this from inside the code editor in your browser.

Inside the code editor, use the navigator sidebar on the left-hand side to navigate to the notebooks directory and open the first notebook.

Follow the instructions on the notebook and work through the notebooks in sequence.

📽 Perform local evaluation

We suggest you evaluate your work locally before submitting your solution. You can do so by running the following command,

dts code evaluate --challenge lx22-collision-check-vali

This should take a few minutes. This is not supposed to be an interactive process: just let it run, and when you return, you will find the output in a folder, including videos, and trajectories, and all the statistics you would usually find on the website.

📬 Submit your solution

When you are ready to submit your homework, use the following command,

dts code submit

This will package all your code and send it to the Duckietown servers for evaluation.

Troubleshooting

If an error of this form occurs

Traceback (most recent call last):
  File "/usr/local/lib/python3.8/dist-packages/duckietown_challenges_cli/cli.py", line 76, in dt_challenges_cli_main
    dt_challenges_cli_main_(args=args, sections=sections, main_cmd="challenges")
  File "/usr/local/lib/python3.8/dist-packages/duckietown_challenges_cli/cli.py", line 203, in dt_challenges_cli_main_
    f(rest, environment)
  File "/usr/local/lib/python3.8/dist-packages/duckietown_challenges_cli/cli_submit.py", line 165, in dt_challenges_cli_submit
    br = submission_build(
  File "/usr/local/lib/python3.8/dist-packages/duckietown_challenges_cli/cmd_submit_build.py", line 41, in submission_build
    raise ZException(msg, available=list(credentials))
zuper_commons.types.exceptions.ZException: Credentials for registry docker.io not available
available:

you need to log into docker using dts. Use this command:

dts challenges config --docker-username <USERNAME> --docker-password <PASSWORD>

Retire obsolete submissions

Note that you can "retire" submissions that you know are wrong. You can do this through the Duckietown Challenges website.

To do so, login using your token, then find the submission you want to retire from the list of submission in your user profile page. Use the button "retire" to the right of the submission record line.