Weather-Monitoring-System-using-RPi-PICO-Microcontroller

This repository contains the source code, schematics, and documentation for a cost-effective and compact Weather Monitoring System built around the Raspberry Pi Pico microcontroller. The system integrates several sensors to measure atmospheric pressure, temperature, humidity, and air quality, while logging data onto an SD card.

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Table of Contents

• Overview
• Features
• Components
• System Architecture
• Installation and Setup
• Usage
• Future Enhancements
• References

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Overview

The Weather Monitoring System (WMS) is designed as a versatile embedded solution for real-time environmental sensing. Utilizing the Raspberry Pi Pico, the system gathers and logs data from:

• BMP280 for atmospheric pressure and temperature,
• DHT11 for temperature and humidity,
• MQ135 for air quality (detecting gases like CO₂, NH₃, benzene, and alcohol), and
• SD Card Module for local data storage.

This project is ideal for applications in meteorology, agriculture, aviation, disaster management, and educational research.

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Features

• Cost-Effective Design: Total BOM cost is kept minimal.
• Compact and Lightweight: Small form factor (21×51 mm) suitable for portable deployments.
• Modular Sensor Integration: Multiple sensors integrated via UART, I²C, and SPI interfaces.
• Data Logging: Continuous logging of sensor data in CSV format to an SD card.
• Low Power Consumption: Efficient operation at 3.3 V with a low power draw.
• Scalability: Foundation for future IoT connectivity and advanced data analytics.

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Components

Component	Description	Approx. Cost (INR)
Raspberry Pi Pico	Microcontroller (RP2040, dual-core, 133 MHz)	349
BMP280	Pressure & Temperature Sensor (±0.12 hPa accuracy)	30
DHT11	Temperature & Humidity Sensor (±2°C, ±5% RH)	48
MQ135	Air Quality Sensor (detects CO₂, NH₃, etc.)	96
SD Card Module	SPI-based Data Logging Module	40
Breadboard & Jumpers	For prototyping and circuit connections	200

Note: Prices and component specifications are based on project estimates.

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System Architecture

Circuit Diagram

The hardware setup includes:

• Raspberry Pi Pico: Serving as the central controller.
• BMP280: Connected via I²C (SDA & SCL).
• DHT11: Digital connection for temperature and humidity.
• MQ135: Analog output connected to an ADC pin.
• SD Card Module: Connected via SPI (MISO, MOSI, SCK, CS).

All sensors are powered by the 3.3 V output of the Pico.

Data Flow

1. Initialization: Power applied and sensors are calibrated.
2. Data Acquisition: Sensors are polled periodically.
3. Data Logging: Readings are formatted as CSV and written to the SD card.
4. Continuous Monitoring: The process repeats as long as power is available.

A flowchart and detailed schematic are available in the repository (see the docs/ folder).

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Installation and Setup

Hardware Assembly

1. Connect the Sensors:

   • Wire the BMP280 to the I²C pins (SDA and SCL).
   • Connect the DHT11 data pin to a digital GPIO (e.g., GP2).
   • Attach the MQ135 analog output to an ADC pin (e.g., GP27).
   • Hook up the SD card module using the SPI interface pins.

2. Power Supply:

   • The system runs on 3.3 V supplied from the Pico.
   • Optionally, use a battery for portable deployment.

Software Requirements

• Arduino IDE: For compiling and uploading the code.
• Libraries:
  • SD.h for SD card operations.
  • Wire.h for I²C communication.
  • SPI.h for SPI interface.
  • DHT.h for the DHT11 sensor.
  • Adafruit BMP280.h for the BMP280 sensor.
  • MQUnifiedsensor.h for the MQ135 sensor.
  • SimpleKalmanFilter.h for sensor data filtering.

Installation

1. Clone this repository:

   git clone https://github.com/yourusername/weather-monitoring-system.git
   cd weather-monitoring-system