Microcontroller-Powered Lunchbox Makes Printed Versions of QR Code Menus

(Image credit: Guy Dupont)

Some restaurants have forgone the use of traditional printed menus in favor of digital menus that can only be accessed by scanning a QR code. This project, put together by maker and developer Guy Dupont, is for those who insist upon reading a physical copy of the menu anyway. Dupont has created a portable lunchbox printer that creates a menu based on the data found at the URL provided by scanning the QR code.

Because the device both scans and prints, the idea was to bring it to restaurants where it could be used to scan the QR code menus and print them at the table. In this case, Dupont is using an ESP-32 microcontroller connected to a generic thermal printer. This module is capable of connecting to the internet, which is necessary to retrieve the menu data.

Dupont breaks down the process into to five separate segments. The device first has to scan the QR code and access the URL. From there, it captures a screenshot of that website using a Microsoft software library known as Playwright. If the website is a PDF, it’s downloaded. Otherwise, the screenshot image is scanned for text.

This text is then taken and sent over to ChatGPT. A request is made to summarize and format the menu text. The response from ChatGPT is then printed onto the thermal printer. This enabled you to get a real time copy of the menu without accessing the website yourself. All you need is an internet connection.

Dupon confirmed the device relies on a Seeed Studio Xiao ESP-32 S3 microcontroller. The software used in the project is open-source and available at GitHub for anyone to explore. Plans are in the works to create a detailed account of the project over at Hackaday.

If you want to get a closer look at this project and even see it in action, check out Dupont's full video on YouTube.

Ash Hill
Contributing Writer

Ash Hill is a contributing writer for Tom's Hardware with a wealth of experience in the hobby electronics, 3D printing and PCs. She manages the Pi projects of the month and much of our daily Raspberry Pi reporting while also finding the best coupons and deals on all tech.

  • Udyr
    ...or just have a printed menu for when a client requests one.
  • Findecanor
    If a restaurant does not have a printed menu, I'll note it down as a future release site for rescued lab animals ...

    In all seriousness: Malicious QR codes are a thing. They have been for years and years.
    You should never scan a QR code that you can't trust, and definitely never use it to pay for something.