ESP32 IoT Vehicle Tracking System

Overview

This project is an autonomous IoT vehicle tracking system built using an ESP32 microcontroller. The device automatically detects journeys using a combination of GPS and accelerometer data, records telemetry to local storage, and seamlessly uploads completed trip information to a server when a trusted Wi-Fi network becomes available. The collected data can be visualized through a companion web application to review routes, monitor driving behavior, and analyze vehicle usage.

Key Features

• Automatic Journey Tracking: Detects trip start and end automatically using a finite state machine; no user interaction required during normal operation.
• Local Data Logging: Writes telemetry data to a microSD card in CSV format, preventing data loss when internet connectivity is unavailable.
• Auto Wi-Fi Uploads: Connects to a predefined Wi-Fi network upon returning to a "home zone" to upload trip files and download remote configuration updates via HTTP.
• Power Management: Utilizes ESP32 deep sleep and wakeup timers when inactive to reduce energy consumption.
• Fault Indication & Manual Override: Includes an LED to alert users to operational issues (e.g., GPS fix failure, SD card errors, failed uploads) and a push button to trigger manual data uploads.
• Remote Configuration: Downloads operational parameters remotely via a stable HTTPS endpoint, avoiding the need to reflash firmware.

Hardware Components

• ESP32 Microcontroller: Central controller managing peripherals and Wi-Fi communication.
• NEO-6M GPS Module: Captures latitude, longitude, speed, altitude, time, and satellite count via UART communication.
• LIS3DH Accelerometer: Measures XYZ acceleration for movement detection via I2C communication.
• microSD Card Module: Provides local storage for trip CSV files via SPI communication.
• Power Source: Power bank (used to avoid high 12V car voltage).

System Logic & State Machine

The system operates on a state machine to prevent false trip recordings from brief movements or GPS inaccuracies. The states include: IDLE -> MOVING_CANDIDATE -> TRIP_ACTIVE -> STOPPED_CANDIDATE -> TRIP_ENDED -> UPLOADING -> SLEEPING

• Start: Triggered by GPS speed exceeding a configurable threshold OR sustained accelerometer movement for a set confirmation period.
• End: Triggered when GPS speed falls below the threshold AND the accelerometer indicates the vehicle is stationary for a configurable duration.

Data Format

Trip files are stored locally in standard CSV format, allowing easy import into databases or spreadsheet software.

Example record:

timestamp, lat, lon, gps_speed_kmph, altitude, satellites, accel_g
2026-06-04T17:10:15Z, 51.294750, 1.062858, 34.2, 73.4, 7, 1.02

Network Communication & Security

• Protocol: HTTP over Wi-Fi (chosen for native ESP32 support and REST API integration).
• Endpoints: Uses Cloudflare Tunnels and a custom domain to provide stable HTTPS endpoints, resolving dynamic IP and local network restriction issues.
• Security: Trusted Wi-Fi network uploads and server-controlled device configurations.

Future Work

• Battery operation optimization.
• Complete GPS power mode switching and LIS3DH interrupt-based wakeup.
• Authentication tokens for improved security.
• Machine Learning (ML) crash detection.
• External cloud deployment of backend analytics and mobile application development.