Firefighter Safety Device

Project Overview

What is FSD?

The Firefighter Safety Device (FSD) is a wearable IoT safety solution that collects critical telemetry — motion, temperature, gas/smoke levels, and GPS location — and transmits it over Wi-Fi to a Firebase backend. A live web dashboard and an Android companion app give fire commanders instant, situational awareness across any device.

Auto Emergency Detection

Detects man-down scenarios (no movement for 30 s) and high temperature automatically — no action required from the firefighter.

Live GPS Tracking

Real-time location plotted on an interactive MapLibre GL map with a trail of the last 50 GPS positions.

Manual SOS Button

A dedicated push button lets firefighters trigger an instant distress signal that overrides all other device states.

Temperature Monitoring

DHT11 sensor reads ambient temperature every loop cycle, triggering progressive alerts as heat rises above safe thresholds.

Gas & Smoke Detection

MQ-2 sensor continuously screens for hazardous combustible gases and smoke, issuing instant warnings when air quality drops.

Multi-Platform Alerts

Visual interfaces, historical trend analysis, and immediate voice/push notification alerts delivered directly to the Web and Android apps.

System Design

System Architecture

Comprehensive IoT ecosystem: Wearable Device → Firebase Cloud Backend → Web Dashboard & Android App. Data flows continuously over secure HTTPS to multiple platforms simultaneously.

Wearable Device

ESP32 MCU
MPU-6050 (Motion)
DHT11 (Temperature)
MQ-2 (Gas & Smoke)
Neo-6M GPS
SOS Button
Buzzer & Battery

→

Firebase Backend

Realtime Database (live)
Firestore (historical)
REST API /api/data
HTTPS PUT from ESP32

→

Command Centers

Next.js Web Dashboard
React Native Android App
Interactive Live Maps
Real-time Push Alerts
Historical Data Analytics

Data Payload (ESP32 → Firebase)

{
  "temperature":   42.5,
  "gas_level":     350,
  "total_acc":     0.98,
  "movement":      "MOVING",
  "status":        "NORMAL",
  "mpu_status":    "OK",
  "dht_status":    "OK",
  "mq2_status":    "OK",
  "gps_status":    "OK",
  "system_status": "OK",
  "latitude":      17.385044,
  "longitude":     78.486671,
  "timestamp":     154823
}

Components

Hardware Components

All components are mounted to the ESP32 and powered by a single HW battery, keeping the device lightweight and wearable for firefighters.

#	Component	Purpose	Interface
1	ESP32	Main microcontroller — Wi-Fi, I2C, UART, GPIO	Core
2	MPU-6050	3-axis accelerometer & gyroscope — motion & fall detection	I²C
3	DHT11	Ambient temperature sensor	1-Wire
4	MQ-2	Gas & smoke sensor — detects LPG, CO, methane, and smoke for toxic environment alerting	Analog
5	Neo-6M GPS	Latitude/longitude tracking	UART
6	Push Button	Manual SOS trigger (GPIO 14 input / GPIO 27 simulated GND)	GPIO
7	Buzzer	Local audible alerts for the firefighter	GPIO
8	Battery	Primary power source — 5V	Power

Pin Map — ESP32

ESP32 Pin	Connected To	Notes
GPIO 21 (SDA)	MPU-6050 SDA	I²C data line
GPIO 22 (SCL)	MPU-6050 SCL	I²C clock line
GPIO 4	DHT11 Data	Single-wire; 10 kΩ pull-up to 3.3 V
GPIO 34 (ADC)	MQ-2 AO (Analog Out)	Analog read — gas/smoke concentration level
GPIO 35 (ADC)	MQ-2 DO (Digital Out)	Threshold-triggered digital alert output
GPIO 16 (RX1)	Neo-6M TX	HW Serial 1 RX
GPIO 17 (TX1)	Neo-6M RX	HW Serial 1 TX
GPIO 14	SOS Button (signal)	Active LOW, INPUT_PULLUP
GPIO 27	SOS Button (GND leg)	Driven LOW — simulated ground
GPIO 13	Buzzer (+)	Active HIGH

Firmware Logic

How It Works

The device runs a non-blocking state machine. Sensor values are read every loop iteration and the system state is updated in real time — no delay() calls that could stall GPS parsing.

Device States

Normal

All parameters within safe limits. Buzzer off.

Warning

Potential danger detected. Buzzer intermittent (1 Hz).

Emergency

Critical condition. Buzzer intermittent (5 Hz).

SOS

Button pressed. Overrides all other states. Continuous buzzer.

Offline

No data received by dashboard. Last known state retained.

Movement Detection — No-Motion Timer

0–10 s
MOVING

10–29 s
WARNING

≥ 30 s
EMERGENCY

The MPU-6050 computes movement = |√(Ax²+Ay²+Az²) − 1.0 g|. If movement drops below 0.07 g the no-motion timer starts. Thresholds of 10 s and 30 s trigger WARNING and EMERGENCY respectively.

Temperature Thresholds

Temperature Range	State	Buzzer Behaviour
< 25 °C	NORMAL	Silent
25 – 30 °C	NORMAL	1 ambient beep / min
30 – 35 °C	NORMAL	2 ambient beeps / min
35 – 40 °C	NORMAL	3 ambient beeps / min
> 40 °C	WARNING →	Escalates to WARNING / EMERGENCY

SOS Button Logic

Toggle Design

First press activates SOS. Second press deactivates it. Debounced at 200 ms to prevent accidental re-triggers.

Simulated Ground Trick

GPIO 27 is driven permanently LOW, acting as the button's GND leg. Eliminates a physical GND wire and simplifies the wiring harness.

Apps & Platforms

Available On

The FSD ecosystem spans multiple platforms — a live web command center and a native Android companion app — giving commanders real-time visibility from any device, anywhere.

Web Dashboard

A full-featured command-center application built with Next.js and Firebase Realtime Database. Monitor live telemetry, GPS location, gas/smoke levels, temperature trends, and emergency alerts from any browser — no installation needed.

Next.js Firebase RTDB Live GPS Map Analytics

Open Dashboard

Android App

A native Android companion app built with React Native & Expo. Receive push alerts, view real-time sensor data, track firefighter GPS location on a mobile map, and trigger SOS acknowledgments — right from your pocket.

React Native Expo Firebase Android APK

Download APK Source Code

Web Application

Web Dashboard

A full-featured Next.js command-center application. Connects to Firebase Realtime Database for live streaming and Firestore for historical analytics.

Live GPS Map Status Cards Temperature Trend Chart Movement Timeline Status Distribution Donut Alert & Event Log Field Units Roster Run Simulation Mode

Left Panel

Status card, battery, sensor row, comm reliability bars, and live scrollable log with timestamped events.

Center Panel

Interactive MapLibre GL map with real-time firefighter position & GPS trail. Field units roster with online/offline indicators.

Right Panel

Temperature min/avg/max badges, line chart (Recharts), movement pixel strip, and status distribution donut chart.

App

App Features

Comprehensive mission-control capabilities integrated directly into the operations dashboard and companion app, providing unparalleled situational awareness, resilience, and analytical depth.

Fleet Monitoring

Tracks multiple firefighter units in one dashboard with fleet cards, status summary, and quick unit switching.

Fallback Polling

Uses Firebase realtime listeners as primary stream, with 1-second polling fallback for resilient refresh in unstable connectivity.

State Mapping

Converts incoming device_state values into NORMAL / WARNING / EMERGENCY / SOS / OFFLINE operational states.

Offline Detection

Marks units OFFLINE when heartbeat/timestamp freshness window is exceeded.

Emergency Handling

Triggers CRITICAL ALERT modal with looping alarm and vibration for EMERGENCY, SOS, and FALL conditions.

Auto-dismiss Alerts

Auto-clears active critical alerts when the triggering unit returns to NORMAL and fall is cleared.

Alert Cooldown

Applies per-unit/per-alert cooldowns to avoid notification/alarm spam during bursty updates.

Geofence Monitors

Loads zones from Firebase (config/geofence_zones) and detects safe-zone breach and danger-zone entry events.

Geofence Fallback

Automatically falls back to built-in default zones when Firebase config is missing/invalid.

History Persistence

Writes periodic incident points to Firebase for debrief and replay workflows.

Incident Replay

Supports replay window selection (1h/3h/6h), playback speeds, play/pause, and frame stepping.

Replay Scrubber

Provides clickable replay timeline points for fast manual scrubbing to incident moments.

Breadcrumb Recovery

Draws recent movement breadcrumbs (20/50/100 points) to support route backtracking/recovery.

Live Movement Trails

Maintains per-unit path trails and displays selected-unit trajectory on map.

Offline Map Style

Switches map rendering into offline-safe style while preserving overlays and operational markers.

Multi-layer Maps

Supports vector and satellite map styles with in-app layer toggle.

External Navigation

Offers map focus/centering action and opens platform navigation apps toward selected unit coordinates.

Geofence Overlays

Renders SAFE/DANGER polygons, live trail, replay path, and breadcrumb overlays simultaneously.

Telemetry Panels

Displays temperature, humidity, gas, movement/state, fall status, and unit-level sensor health states.

Analytics Panel

Shows status breakdown and sensor health summary for command awareness.

Theme Toggle

Runtime dark/light theme switching for better readability across lighting conditions.

Backend

API Endpoints

The Next.js server exposes a REST route for alternative HTTP-based ingestion and for writing to the Firestore historical collection.

POST /api/data

Receives sensor data from ESP32 (or any HTTP client) and stores it in Firestore.

Request Body

{
  "device_id":  "FF_001",
  "temperature": 42.5,
  "movement":   "MOVING",
  "status":     "NORMAL",
  "latitude":   17.385044,
  "longitude":  78.486671
}

Response Codes

200  { "success": true }
400  { "error": "device_id is required" }
503  { "error": "Firebase not initialized" }
500  { "error": "Internal server error" }

Transparency

Assumptions & Known Limitations

This is a functional prototype. The following constraints are acknowledged and are planned to be addressed in future production versions.

Area	Detail
GPS indoors	Neo-6M signal degrades inside buildings. Dashboard retains last known location.
DHT11 accuracy	±2 °C — suitable for prototypes. Production should use DHT22 or SHT31.
Single firefighter	Firmware hardcoded for device ID `FF_001`. Multi-device support is planned.
Firebase auth	Uses legacy Database Secret. Should use Firebase Auth tokens in production.
SSL verification	`client.setInsecure()` disables cert verification. Production must verify the server cert.
Timestamp	ESP32 sends `millis()` (uptime), not wall-clock time. Dashboard uses server local time.
Connectivity	Wi-Fi range ~50–100 m indoors. LoRa / GSM upgrades planned for larger deployments.

Project Team

Team

This project was brought to life by a team of dedicated engineers. FSD is the output of their sleepless nights and efforts.

RSMK

Srinivasa Manikanta

Developed the software stack, logic, and dashboard.

Chintu

Santhosh

Handled presentations and assisted with hardware.

chaitu

Sri Chaitanya

Assembled hardware connections for the prototype.

Ramu

N Ramu

The mastermind behind the companion APP.

Sairam

The mastermind behind the new website.

Firefighter
Safety Device

What is FSD?

System Architecture

Data Payload (ESP32 → Firebase)

Hardware Components

Pin Map — ESP32

How It Works

Device States

Movement Detection — No-Motion Timer

Temperature Thresholds

SOS Button Logic

Available On

Web Dashboard

App Features

Project Gallery

Technologies Used

Firmware (ESP32)

Web Dashboard

API Endpoints

Assumptions & Known Limitations

Team

FirefighterSafety Device

What is FSD?

System Architecture

Data Payload (ESP32 → Firebase)

Hardware Components

Pin Map — ESP32

How It Works

Device States

Movement Detection — No-Motion Timer

Temperature Thresholds

SOS Button Logic

Available On

Web Dashboard

App Features

Project Gallery

Technologies Used

Firmware (ESP32)

Web Dashboard

API Endpoints

Assumptions & Known Limitations

Team

Firefighter
Safety Device