"False Alarms Kill Trust. We Kill False Alarms."
Guardian is a next-gen safety application that combines low-power native sensors with on-device AI to distinguish real crashes from phone drops. It acts as an intelligent gatekeeper—verifying incidents before disturbing emergency services.
Most crash detection apps drain battery or trigger on every phone drop. Guardian solves this by splitting detection into two phases: The Trigger and The Judge.
- Technology: Native Android Service (Kotlin).
- Function: Runs silently in the background using minimal battery. It monitors the accelerometer and gyroscope for sudden spikes (>2.5G) or violent rotations.
- Role: It is the "Watchdog" that only wakes up the app when absolutely necessary.
Guardian uses a Two-Stage Hybrid Inference pipeline to ensure accuracy, privacy, and battery efficiency.
- Engine: TensorFlow Lite (YAMNet Model).
- Process: Instantly records 10 seconds of raw audio (16kHz, Mono) and scans for high-risk acoustic signatures offline.
- Triggers: Glass Breaking, Vehicle Impact, Skid/Squeal, Airbag Explosion, Screaming.
- Engine: Pollinations AI (GenAI).
- Process: Acts as a forensic investigator. It combines G-Force Data + Detected Audio Tags to determine context.
- Context: Distinguishes between a Phone Drop (High G + Silence) and a Car Crash (High G + Impact Sounds).
The AI follows a strict logic protocol to filter false alarms:
| G-Force | Audio Evidence (YAMNet) | Verdict | System Action |
|---|---|---|---|
| > 4.0 G | "Crash", "Glass", "Bang" | CRITICAL 🚨 | SOS SENT + Hospital Alert |
| < 3.0 G | "Silence", "Music", "Speech" | FALSE ALARM ✅ | GREEN SCREEN (Event Ignored) |
| High | "Microphone Error" | FAIL-SAFE |
SOS SENT (Safety First) |
Fail-Safe Protocol: If the Cloud AI server is unreachable (Offline/502), the system automatically defaults to CRITICAL mode. We prioritize saving a life over avoiding a false alarm in worst-case scenarios.
- ⚡ Smart Sensor Fusion:
- Native background processing filters out "Freefall" events (phone drops) before they even reach the AI.
- 🚫 False Alarm Prevention (Green Screen Protocol):
- If the AI determines the event is safe (e.g., loud music + low impact), the screen turns GREEN ("False Alarm").
- No SMS is sent, and the event is logged as "Ignored" to prevent panic.
- 🏥 Hospital Dispatch Dashboard:
- A dedicated tablet interface for paramedics.
- Shows exact crash location and allows responders to listen to the audio evidence before dispatching.
- 📍 Instant SOS with Live Tracking:
- If verified as CRITICAL, the app sends an SMS with high-accuracy Google Maps coordinates to emergency contacts.
- Fail-Safe Mode: If the AI server is unreachable, the system defaults to "Critical" to ensure safety.
| Select Role | Login Screen | Emergency Contacts | Home Monitoring |
|---|---|---|---|
 |
 |
 |
 |
| Choose User or Hospital | Secure Sign-In | Manage Trusted Contacts | Active Protection Mode |
| Crash Detected | AI Analysis | False Alarm | Connecting Hospital | SOS Sent |
|---|---|---|---|---|
 |
 |
 |
 |
 |
| Real-time Alert Countdown | Processing Sensor Data | AI Cancels Alert | Finding Nearby Help | Alerts Dispatched |
| Dashboard Feed | Hospital Portal | Incident Details | Location View | Case Accepted |
|---|---|---|---|---|
 |
 |
 |
 |
 |
| Incoming Feed | Admin Login | Severity Data | Map Location | Dispatch Confirmed |
Guardian leverages powerful open-source libraries to achieve real-time safety:
geolocator: ^14.0.2– Fetches high-accuracy GPS coordinates for the SOS link.sms_sender_background: ^1.0.6– Sends critical SMS alerts even if the app is minimized.record: ^6.1.2&path_provider– Records the 10-second "Black Box" audio evidence in WAV format.audioplayers: ^6.5.1– Allows hospitals to playback the crash audio.
google_generative_ai: ^0.4.0– Powers the Cloud AI decision-making (Gemini/Pollinations integration).tflite_flutter– Runs the offline YAMNet audio model (on-device).firebase_core,auth,firestore– Handles real-time syncing between the User and Hospital Dashboard.
permission_handler: ^12.0.1– Manages critical access to SMS, Location, and Microphone.shared_preferences– Stores emergency contacts locally for offline access.url_launcher– Opens Google Maps for route navigation.
To run this project successfully, you must complete these configuration steps:
The SOS feature will NOT work until you add contacts.
- Open the app → Login → Go to "Manage Emergency Contacts".
- Add at least one phone number (e.g., your own secondary number for testing).
This app uses Google services for Maps and AI.
- Google Maps API: Ensure your API key is added to
android/app/src/main/AndroidManifest.xml. - Gemini/Pollinations AI: If you are using a specific API key for the AI service, ensure it is updated in
lib/services/sensor_service.dartorlib/services/google_places_service.dart.
Since we cannot crash a real car on stage, the app includes a Secret Demo Menu on the Home Screen:
- Test False Alarm (Button A):
- Simulates 2.5 G-Force (Minor Bump).
- AI Analysis: "Low Impact + No Crash Sounds" → FALSE ALARM.
- Result: Green Screen, No SMS.
- Test Real Crash (Button B):
- Simulates 8.8 G-Force (Severe Impact).
- AI Analysis: "High G-Force Threshold Exceeded" → CRITICAL ALERT.
- Result: Red Screen, SMS Sent to contacts.
- Clone & Install:
git clone [https://github.com/vibhutomer/guardian.git](https://github.com/vibhutomer/guardian.git) cd guardian flutter pub get - Setup Assets:
- Ensure
assets/yamnet.tfliteandassets/icon.pngare present.
- Ensure
- Run:
flutter run
- Vibhu Tomer - Flutter Developer, System Architect & Firebase Integration
- Sharukh Ahamad - Kotlin & Native Modules Developer
- Shavez Ali - Kotlin & Sensor Logic Developer
- Jaskaran Singh - AI Engineer & Model Integration
Guardian is a prototype safety aid. While the Hybrid Gatekeeper significantly reduces false alarms, no system is 100% perfect. Always drive responsibly.