System Capabilities & Hardware Abstraction
Guiak abstracts hardware differences to deploy identical accessibility logic across both battery-powered and mains-powered microcontrollers.
Hardware Comparison
| Feature | ESP32-S3 DevKit-C | Arduino UNO R4 WiFi |
|---|---|---|
| Primary Power | Li-Ion Battery (ADC Voltage Monitoring) | Mains / 5V External Power Bank |
| Self-Test (POST) | Automated boot detection of I2S, RFID, and ADC with acoustic chime and fault-tolerant degradation | Peripheral detection with safe bypass |
| Operating Schedule | 06:30 - 20:30 (Early morning 6:30 AM wake-up for school access + night power saving) | 06:30 - 20:30 (Synchronized via NTP / Firebase) |
| Audio Synthesis | I2S Digital (MAX98357A / PCM5102) | 12-bit Analog DAC (Pin A0) / Tone Buzzer |
| Bluetooth Radio | Native BLE 5.0 (10 Hz iBeacon @ -59 dBm 1m + Low-latency GATT Server) | ArduinoBLE (iBeacon broadcast) |
| RFID Module | SPI Interface (GPIO 10, 11, 12, 13, 9) | Hardware SPI (Pins D10, D11, D12, D13, D9) |
| Energy Saving | Wi-Fi Modem Sleep + 0 µA Audio Cutoff | Wi-Fi Standby |
| Fault Recovery | Hardware Watchdog Timer (8s timeout) | Software Watchdog Recovery |
Presence Detection System
Guiak provides dual presence recognition to give teachers, special education tutors, and administrative staff peace of mind:
- Hands-Free Proximity (BLE): When a visually impaired student passes near the door frame, their mobile device automatically registers with the doorway node without requiring physical touch.
- Physical RFID Tap: For attendance verification or access control, the student can tap their RFID card on the accessible lower sensor, triggering a confirmation chime and recording an immutable timestamp.
Firebase Cloud Integration
All doorway nodes synchronize with a centralized Firebase Realtime Database schema:
/nodes/[roomCode]/config.json: Room labels, floor, volume levels, and operating hours (06:30 schedule)./nodes/[roomCode]/status.json: Online heartbeat, battery %, RSSI, and uptime./nodes/[roomCode]/command.json: Cloud-to-node dispatcher (remote acoustic pulse, lockdown)./students/[studentId]/lastSeen.json: Last recorded location and timestamp for registered students.
Software Repository & Ecosystem
Full source code for the firmware, companion accessible mobile apps, documentation, and releases are maintained directly on our official GitHub repository.
Mobile Application Status & Accessibility
The companion Android mobile application is under active development and is not 100% perfected. Continuous efforts are underway; enhancing screen reader workflows and access for blind users remains an active priority.
Educational Deployment Without Prior Notice
All high schools, colleges, and educational institutes are authorized to deploy and use Guiak freely in their facilities without needing to notify or seek prior consent from the author.