Overview & Background
The current self-service checkout system used by our student guild has served its purpose faithfully for over a decade. However, maintaining it has become increasingly difficult due to its age and reliance on outdated technologies.
Together with the guild’s webmaster team, we began exploring potential new directions. I had previously experimented with running Flutter directly on a Raspberry Pi, and the results seemed promising. We also wanted to integrate a balance system that allows users to track their account credit.
Issue addressed: Replace an outdated self-checkout system with a maintainable, modern, and extensible solution, while also introducing personalized balance tracking.
Development Process
This project challenged me on multiple levels. We acquired a touch display and began testing Flutter’s performance with it. The outcome was excellent—Flutter ran very smoothly—so I was tasked with designing the system’s structure.
I began planning a frame using 2020 aluminum profiles. As I developed the 3D model, the design direction naturally evolved. The profile system allows for easy panel mounting and leaves enough space inside for power supplies and other electronics.
I built a 12V power system for the device, which now includes speakers, LEDs, an RFID reader, a barcode scanner, and a touch display. Users are identified using RFID tags, allowing them to purchase items based on their account balance, with every transaction being recorded for traceability.
Once the frame prototype was in place, we began designing a simple and intuitive user interface to ensure a smooth user experience.
Outcome
- A functional device that allows users to browse a product list or scan items via barcode to make purchases autonomously.
- User authentication is handled via RFID, linking transactions to individual accounts.
Next Steps / Future Improvements
- Optimize internal space usage and cable management for better reliability.
- Integrate lighting indicators that respond to system events for improved user feedback.
Technologies & Tools
- Dart / Flutter
- Raspberry Pi