Wildfire Operations Center & LoRa Sensor Fleet
An end-to-end IoT disaster response system connecting field-deployed ESP32 sensor nodes over 433 MHz LoRa radio to a real-time GIS situational operations center.
Wildfires in remote forests spread rapidly before satellite or observation aircraft detect them. Cell towers frequently fail or have zero coverage in deep timber terrain, preventing standard internet sensor deployment.
Designed a resilient mesh telemetry pipeline: autonomous ESP32 nodes equipped with DHT22, MQ-2 smoke sensors, and IR flame photodiodes transmit telemetry over 433 MHz LoRa radio to a central base station gateway. A local Python serial bridge ingests packets and feeds an SSE-driven GIS situational dashboard.
Rather than relying on continuous polling or cellular SIM modems at every sensor node, used low-power SX1278 LoRa radio modules (SF7, 125 kHz BW) with interrupt-driven sleep cycles, achieving multi-kilometer transmission range through dense forest canopy with minimal battery drain.
LoRa packet sizes are strictly bandwidth-constrained; raw sensor dumps were compressed into compact binary byte packets and decoded on the Python gateway bridge rather than transmitting verbose JSON over the air.
System Motivation & Problem
Early detection is the single most critical factor in controlling wildfire escalation. Traditional monitoring relies on satellite thermal imaging (which suffers from multi-hour orbital pass latency) or human lookout towers. This system was engineered to deploy cheap, solar-assisted hardware nodes directly into high-risk forest perimeters with zero cellular dependency.
Physical Hardware & Radio Architecture
- Sensor Nodes: Custom ESP32 microcontrollers wired to DHT22 temperature/humidity sensors, MQ-2 analog gas/smoke detectors, and high-sensitivity optical flame sensors.
- LoRa RF Telemetry: SX1278 transceivers transmitting at 433.0 MHz (Spreading Factor 7, Bandwidth 125 kHz, Coding Rate 4/5) to penetrate foliage and rugged topography.
- Base Station Gateway: Receiver node interfaced via high-speed USB Serial (115200 baud) running a daemonized Python bridge.
Software & Cloud Operations Center
The Python serial bridge parses structured hardware packets (GATEWAY_PACKET:<payload>), performs physical range verification and deduplication, and streams records into a PostgreSQL database with Server-Sent Events (SSE) pushing immediate coordinate updates to the browser GIS dashboard.
Key Architectural Decisions
Zero-Cloud Fail-Safe
If cloud internet connectivity drops, the base station gateway continues logging telemetry locally to an encrypted SQLite circular buffer, automatically reconciling and syncing records once WAN connectivity recovers.