Low-cost head-mounted camera system for medication-error detection

We present a low-cost, reproducible head-mounted wearable system for first-person video capture and real-time medication-workflow monitoring. The device combines a Raspberry Pi Zero W, Pi Camera Module v3, PiSugar 2 Pro battery board, active buzzer, tactile push button, and a modular 3-D-printed PLA enclosure with elastic head straps. Weighing approximately 145 g and costing about USD 100 for the core wearable components (USD 168.78 for the complete development and configuration bill of materials), the system is designed for offline operation, local storage, and low-power embedded processing. The enclosure was modeled in DesignSpark Mechanical and fabricated as modular panels with integrated mounting, ventilation, and access features. The software stack runs on Raspberry Pi OS Lite with Python/OpenCV scripts for autonomous capture, local event flagging, and audible feedback. Pilot deployment confirmed stable operation, up to 7 h of battery-powered use, and practical wearability in clinical settings. This work provides a reproducible open-hardware platform for wearable monitoring in low-resource operating room environments.