Picture Book Locker
Chunxiao Technology · 2020 – 2023
Role: Android Developer (Cabinet Host + Client App)
Cover
1 / 1924/7 smart self-service library cabinet for schools. Cabinet-side Android host controls 10+ hardware peripherals via UART/RS485 and GPIO: electromagnetic locks, UV-C lamps, LED strips, RFID high-frequency antennas, face recognition camera, card reader, receipt printer, door sensors. Separate borrower Android app with face/QR auth for <3s transactions. Admin backend handles book catalog, locker init, and cabinet API orchestration. After the other Android dev resigned, handled escalation and scope rebalancing to keep delivery on track.
<3s
Borrow Time
0%
Book Loss
24/7
Uptime
10+
Hardware Peripherals
Multiple
Schools
Problem
Schools need 24/7 self-service book borrowing when libraries are closed, with hygienic handling, robust hardware control, and simple auth (face/QR/RFID) for children.
Solution
Smart locker cabinet: Android host controlling 10+ hardware peripherals (locks, UV-C, RFID antennas, face camera, card reader, printer, sensors) via UART/RS485 and GPIO. Separate borrower Android app with face recognition + ZXing QR auth. Spring Cloud backend for book catalog management, locker initialization, and cabinet API orchestration.
Key Highlights
- ▸Programmed Android control stack for 10+ hardware peripherals via UART/RS485 and GPIO: electromagnetic locks, UV-C lamps, RFID antennas, face camera, card reader, receipt printer, sensors
- ▸Shipped borrower-facing Android app for self-service check-out and return with face/QR auth
- ▸Sustained 24/7 unattended multi-cabinet operation across multiple schools
- ▸After colleague resigned, escalated workload to leadership, negotiated scope split (retained cabinet host, handed off To-C mobile app), kept delivery on track
Tech Stack
What I Learned
Hardware integration demands robust fail-safes for every component; UV disinfection timing must be precise; escalate workload early rather than silently risking milestones — scope rebalancing kept the project on track.