Linux BLE Security Monitoring System

A motion-activated security system built using an Arduino Nano, STHS34PF80 infrared motion sensor, Bluetooth Low Energy (BLE), and a Linux server.

When motion is detected, the Arduino sends a BLE notification to a Linux host, which records video, converts it to a Discord-compatible format, and uploads both a timestamped alert and recording to a Discord channel.

Features

• Interrupt-driven motion detection using the STHS34PF80
• Bluetooth Low Energy communication via HM-10
• Linux-based monitoring service using Python and Bleak
• Automatic webcam recording using OpenCV
• FFmpeg video conversion to H.264 MP4
• Discord webhook notifications and video uploads
• Protection against duplicate recordings using asyncio locks

System Architecture

STHS34PF80 Motion Sensor

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    Arduino Nano

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     HM-10 BLE

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    Linux Server

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    OpenCV Webcam

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   FFmpeg Convert

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Discord Notification

Technologies Used

Embedded

• Arduino Nano
• Adafruit STHS34PF80 Library
• Hardware Interrupts
• SoftwareSerial

Linux / Software

• Python
• asyncio
• Bleak
• OpenCV
• FFmpeg
• Discord Webhooks

Example Workflow

1. Motion is detected by the STHS34PF80.
2. The sensor asserts its interrupt pin.
3. The Arduino sends a BLE notification.
4. The Linux service receives the event.
5. A video recording begins automatically.
6. FFmpeg converts the recording to H.264 MP4.
7. A timestamped alert and video are uploaded to Discord.

Future Improvements

• Automatic startup with systemd
• BLE reconnection handling
• Final Recording after BLE disconnect/powerloss
• Multiple camera support
• Local event database
• Battery-backed operation

Lessons Learned

This project provided experience with:

• Embedded firmware development
• Hardware interrupts
• BLE communication
• Linux systems programming
• Asynchronous Python programming
• Video processing pipelines
• End-to-end embedded system integration