Overview

This system collects environmental data from a greenhouse using Arduino-based sensor nodes and transmits it via light signals (VLC) to a receiver node. The data is then relayed through a local server to a backend API, where it is stored and served to a real-time web dashboard. Operators can monitor greenhouse conditions and control actuators (fans, lights, water pump) remotely through the web interface.

Architecture

[Transmitter (Arduino)]
        │
        │  Visible Light Communication
        ▼
[Receiver (Arduino)]
        │
        │  Serial Communication
        ▼
[Local Server (Node.js)]
        │
        │  HTTP / WebSocket
        ▼
[Backend Server (Node.js + PostgreSQL)]
        │
        │  REST API
        ▼
[Frontend Dashboard (React + TypeScript)]

Modules

Module	Description	Tech
transmitter	Reads sensor data and encodes it into light signals	Arduino / C++
receiver	Decodes incoming light signals and forwards data via serial	Arduino / C++
local-server	Bridges serial port data to the backend server	Node.js / TypeScript
backend-server	REST API that stores and exposes sensor data	Node.js / TypeScript / PostgreSQL
frontend	Web dashboard for real-time monitoring and control	React / TypeScript / Tailwind CSS

Features

• VLC-based communication — sensor data is transmitted via modulated light signals between Arduino nodes, with no RF or Wi-Fi required between hardware units
• Real-time monitoring — live dashboard displays current greenhouse conditions
• Multi-sensor support — tracks temperature, humidity, light intensity, and soil moisture
• Actuator control — remotely toggle fans, grow lights, and water pump from the web interface
• Persistent storage — historical sensor data is stored in PostgreSQL

Tech Stack

• Hardware: Arduino (C / C++)
• Communication: Visible Light Communication (VLC), Serial port
• Local Server: Node.js, TypeScript, SerialPort
• Backend: Node.js, Express, TypeScript, DrizzleORM, PostgreSQL
• Frontend: React, TypeScript, Vite, TailwindCSS, RechartJS