Smart Bike Light Grp07 V03

🚲 ESP32 Smart Bike Tracker

An ESP32-based smart tracking and monitoring system for bicycles, combining GNSS (GPS) tracking, motion detection, power management, battery monitoring, and LoRa communication to create an intelligent, low-power system for bike security and telemetry.

📚 Table of Contents

• Features
• Getting Started
• Power Modes
• GNSS (GPS) Handler
• Motion Detector
• Light Control
• LoRa Communication
• Battery Monitoring
• Inactivity Handling
• Main Loop Overview
• Modules Summary
• Contributing
• License

📦 Features

• Real-time GPS tracking
• LoRa communication to send bike data remotely
• Motion detection using an accelerometer
• Battery monitoring via MAX17048 fuel gauge
• Smart power management with 3 modes: ACTIVE, PARK, SLEEP
• Inactivity-based sleep transitions
• Wake-up on button press or timer
• Integrated button and light control

🛠️ Getting Started

✅ Prerequisites

• PlatformIO or Arduino IDE
• ESP32 board definitions installed
• Required libraries:
  • TinyGPS++
  • Wire
  • SPI

🚀 Flashing the Firmware

git clone https://github.com/youruser/esp32-smart-bike-tracker.git
cd esp32-smart-bike-tracker
# Open with Arduino IDE or PlatformIO and upload to your ESP32

🔘 Button Handler

Manages button input from GPIO 33, used to:

• Wake up the system
• Trigger GPS updates
• Toggle power modes

⚙️ Configuration

#define BUTTON_PIN_1 33

📦 Variables

extern volatile bool button1Pressed;
extern unsigned long lastActivityTime;

📋 API

🧠 Power Modes

System behavior varies by mode:

🟢 ACTIVE Mode

• Full GPS + LoRa operation
• Motion detection and lighting enabled
• Auto-exit on inactivity

🟡 PARK Mode

• Enters light sleep
• Periodic wake via RTC or button
• Ideal for short-term stationary periods

🔴 SLEEP Mode

• Enters deep sleep for max power saving
• Wake on button press only
• Best for long inactivity

🛰 GNSS (GPS) Handler

Handles GPS data using the TinyGPS++ library. Sends the location everytime the mode of the system changes.

📋 API

📍 Example

This flag is used to update the location and send it.

if (sendLocationFlag) {
    GPSPosition pos = gnss.checkLocation();
    // Use pos.latitude, pos.longitude
}

🕹️ Motion Detector

Detects bike movement using a 3-axis accelerometer (e.g. ADXL345).

📋 API

MotionDetector motion(0x53); // ADXL345 default I2C address

💡 Light Control

Uses an LDR + MAX7219 LED matrix to control lights.

⚙️ Configuration

📋 API

📡 LoRaWAN Communication

Handles uplink/downlink communication via RN2483 LoRa module using OTAA.

🔧 ESP32 to RN2483 Wiring

📋 API

📤 Uplink Format (CSV)

1,3.85,12.34,56.78

📥 Downlink Format

TTN → JSON string in HEX:

{"value": 2}

TTN Payload: 7b2276616c7565223a20327d

Parsed into int value = 2.

🔋 Battery Monitoring

Powered by the MAX17048 fuel gauge.

batterypercentage = battery.percent();

Low battery warning is triggered by:

manageBatteryWarning(batterypercentage);

⏱️ Inactivity & Mode Handling

Automatically switches to PARK mode if idle for 60 seconds:

if (millis() - lastActivityTime > 60000) {
    // Switch to PARK
}

Button interrupt handler toggles modes:

void IRAM_ATTR handleInterrupt1();

Transitions:

• ACTIVE → PARK
• PARK → SLEEP

🔁 Main Loop Structure

switch (getCurrentMode()) {
    case ACTIVE:
        // Motion + LoRa
        break;
    case PARK:
        // Light sleep
        break;
    case SLEEP:
        // Deep sleep
        break;
}

🛠 Modules Summary

Authors

Group 7 in the DTU course 34346 Networking technologies and application development for IoT