LIFEBAND: A Long-Range, Low-Power Wearable for Real-Time Aquatic Distress Detection

Abstract

Drowning is a leading cause of accidental aquatic mortality worldwide, highlighting the need for robust emergency detection in infrastructure-constrained environments. LifeBand is an edge-computing wearable engineered for real-time aquatic physiological distress recognition, long-range emergency telemetry, and automated dispatch triggering. The device incorporates a multi-modal sensor array including a photoplethysmography (PPG) heart rate sensor, a 6-axis inertial measurement unit (IMU), a piezoelectric impact sensor, and a GPS module all managed by an ESP32 system-on-chip. By executing sensor fusion locally on the edge, LifeBand classifies submersion events using dynamic threshold analysis of photoplethysmographic variance, impact dynamics, sustained immobility, user profile and battery status. Upon distress, LifeBand constructs a standardized telemetry packet and broadcasts it over a 915 MHz LoRa network without reliance on cellular towers or Wi-Fi infrastructure. A gateway base station ingests the packet, logs the incident, triggers trimodal (auditory, optical, haptic) alarms, and provides victim locations and distress scores on a monitoring dashboard as well as on a mobile app. The scope of work includes a working prototype of the hardware and software components, reliability experiments and simulated telemetry results. The experimental results and the prototype implementation show that Lifeband is a reliable, affordable, safety solution that scales from swimming-pool facilities, to open water flood rescue operations, accelerating response to
mitigate aquatic fatalities.