Published February 21, 2020 © GPL3+

Smart Room Lighting with ESP32

Use some LED panels and strips along with an ESP32 and local webserver to control the lighting of a room from anywhere in the house.

IntermediateFull instructions provided2 hours12,797

Things used in this project

Hardware components

SparkFun ESP32 Thing

Power MOSFET N-Channel

Seeed Studio Grove - Relay

RGB LED Strip- Analog

Software apps and online services

Arduino IDE

Microsoft VS Code

Node.JS

MySQL Server

Story

Purpose

I recently purchased several new lights for an auxiliary workspace in my room, but there was a problem: it took far too long to turn the lights on and off. I also wanted to add some colored ambient lighting, and that also needed a way to be controlled, so I decided to create a web-based controller and WiFi-connected hardware to adjust the lights.

Hardware Needed

First and foremost, there had to be a webserver running the necessary services, such as MySQL, NodeJS, and Apache. I have published a guide on how to convert an old PC into a home server that can run all of these, which can be viewed here. If you don’t wish to use an entire PC, a simple Raspberry Pi can work, albeit quite a lot slower.

The hardware includes a relay that is rated for up to 120V AC @ 10A for the primary lights, an analog LED strip, a few MOSFETs, and finally, an ESP32 for the brain.

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I chose to use SparkFun’s ESP32 Thing board, but almost any ESP32 board variant should suffice.

MySQL DB Setup

I began the project by first diagramming what exactly I wanted the DB to capture, including the state, color, and location of each light involved. I accomplished this by making an ER (entity-relationship) diagram as follows, and it shows that each Light has an ID, on/off value, and location.

Additionally, RGB lights inherit the traits above, but also have an RGB value as well. The tables closely mirror the ER diagram, and they were set up like so:

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Finally, I added two lights to the DB: one regular Light, and one RGB Light.

Node.JS Backend Webserver

In order to facilitate communication between the web client, DB, and ESP32, I needed to add a webserver into the stack. At a basic level, it takes in requests via an API to change the color/state of the lights, which get stored in the DB via queries. Clients are also able to access the current values of two of the lights via an API, and they receive a JSON object back, which contains the RGB and state values.

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Credentials for the MySQL DB are stored in the config.js file, along with the IDs of the lights being controlled and the port the service is running on.

Lighting Control Frontend

The lights are controlled by a webpage that is hosted on an Apache webserver. It features a sliding switch, preview window, RGB sliders, and a few preset buttons. Whenever the user changes the color, it sends that data to the NodeJS server.

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It also gets the current value from the server every few seconds, which allows for multiple users to have concurrent access.

The ESP32 Program

Lastly, the ESP32 runs a program that fetches the current values from the NodeJS webserver, parses them, and displays them on the lights. In the setup() function, the board connects to the WiFi AP, the RGB pins are attached to three PWM timers, and the relay pin is set as an output.

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The loop() function first checks if the board has a connection to the AP, and if it does, it sends a GET request to the server, and gets a response in the form of a String. That payload is then parsed into a JSON object using the ArduinoJSON library, and then the values are sent to their respective functions to change the states of the lights.

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Expanding the System

In the future, I would like to modify the web interface to allow for new lights to be added, as well as select multiple ones from a list. That way, the entire system can scale easily. Imagine, clicking on a light that is inside of a lamp, knowing that it’s toggleable, and being able to change it by clicking a button on your phone from bed.

Code

<html>
<head>
    <title>Change Room Lighting</title>
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <script src="/common/jquery-3.4.1.js"></script>
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css">
    <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.16.0/umd/popper.min.js"></script>
    <script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.4.1/js/bootstrap.min.js"></script>
    <style type="text/css">
        .switch input {
            opacity: 0;
            width: 0;
            height: 0;
        }
        .switch {
            position: relative;
            display: inline-block;
            width: 60px;
            height: 34px;
        }
        .slider {
            position: absolute;
            cursor: pointer;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background-color: #ccc;
            -webkit-transition: .4s;
            transition: .4s;
        }
        .slider:before {
            position: absolute;
            content: "";
            height: 26px;
            width: 26px;
            left: 4px;
            bottom: 4px;
            background-color: white;
            -webkit-transition: .4s;
            transition: .4s;
        }

        input:checked + .slider {
            background-color: #2196F3;
        }

        input:focus + .slider {
            box-shadow: 0 0 1px #2196F3;
        }

        input:checked + .slider:before {
            -webkit-transform: translateX(26px);
            -ms-transform: translateX(26px);
            transform: translateX(26px);
        }

            /* Rounded sliders */
        .slider.round {
            border-radius: 34px;
        }

        .slider.round:before {
            border-radius: 50%;
        }

        #preset-container {
            width: 85%;
        }

        #preview-container {
            width: 150px;
            height: 150px;
            background-color: black;
        }

        .accordion {
            background-color: #eee;
            color: black;
            cursor: pointer;
            padding: 18px;
            width: 100%;
            text-align: center;
            border: none;
            outline: none;
            transition: 0.4s;
        }

            /* Add a background color to the button if it is clicked on (add the .active class with JS), and when you move the mouse over it (hover) */
        .active, .accordion:hover {
            background-color: #ccc;
        }

        .panel {
            padding: 0 18px;
            background-color: white;
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.2s ease-out;
        }

        .accordion:after {
            content: '\02795'; /* Unicode character for "plus" sign (+) */
            font-size: 13px;
            color: #777;
            float: right;
            margin-left: 5px;
        }

        .active:after {
            content: "\2796"; /* Unicode character for "minus" sign (-) */
        }

        .btn {
            position: relative;
            margin: 0 auto;
        }

        .aligner {
            display: flex;
            justify-content: center;
        }

/* #region button colors */

        #neutral-black-btn
        {
            background-color: black;
            color: white;
        }

        #neutral-white-btn
        {
            color: black;
            background-color: white;
        }

        #neutral-light-gray-btn
        {
            color: black;
            background-color: lightgrey;
        }
        #neutral-dark-gray-btn
        {
            color: white;
            background-color: darkgrey;
        }
        #solid-red-btn {color:white; background-color: red;}
        #solid-green-btn {color:white; background-color: green;}
        #solid-blue-btn {color:white; background-color: blue;}
        #solid-purple-btn {color:white; background-color: purple;}

        #neon-pink-btn {color:white; background-color: rgb(255, 133, 153);}
        #neon-green-btn {color:white; background-color: rgb(118, 255, 54);}
        #neon-blue-btn {color:white; background-color: rgb(45, 101, 255);}
        #neon-purple-btn {color:white; background-color: rgb(172, 70, 255);}

/* #endregion */

    /*.slider-container {
        width: 40%;
    }*/

    .range-slider {
        -webkit-appearance: none;  /* Override default CSS styles */
        appearance: none;
        width: 100%; /* Full-width */
        height: 25px; /* Specified height */
        background: #d3d3d3; /* Grey background */
        outline: none; /* Remove outline */
        opacity: 0.7; /* Set transparency (for mouse-over effects on hover) */
        -webkit-transition: .2s; /* 0.2 seconds transition on hover */
        transition: opacity .2s;
        margin-bottom: 15px;
    }

    .range-slider:hover {
        opacity: 1; /* Fully shown on mouse-over */
    }

        /* The slider handle (use -webkit- (Chrome, Opera, Safari, Edge) and -moz- (Firefox) to override default look) */
    .range-slider::-webkit-slider-thumb {
        -webkit-appearance: none; /* Override default look */
        appearance: none;
        width: 25px; /* Set a specific slider handle width */
        height: 25px; /* Slider handle height */
        background: red; /* Green background */
        cursor: pointer; /* Cursor on hover */
    }

    .range-slider::-moz-range-thumb {
        width: 25px; /* Set a specific slider handle width */
        height: 25px; /* Slider handle height */
        background: red; /* Green background */
        cursor: pointer; /* Cursor on hover */
    }

    #slider-container {
        width: 100%;
    }

    #redRange::-webkit-slider-thumb, #redRange::-moz-range-thumb {
        background: red;
    }

    #greenRange::-webkit-slider-thumb, #greenRange::-moz-range-thumb {
        background: green;
    }

    #blueRange::-webkit-slider-thumb, #blueRange::-moz-range-thumb{
        background: blue;
    }


    </style>
    <script>
        const serverBaseURL = "http://<IP>:<port>/lighting/";

        function refreshState()
        {
            $.getJSON(serverBaseURL + "getState", (data, status, xhr) => {
                setColor(data.colors.r, data.colors.g, data.colors.b, false);
                $('#toggle-switch-primary').prop('checked', data.toggleVal);
            });
        }

        function setColor(r, g, b, send_data)
        {
            $("#preview-container").css("background-color", `rgb(${r}, ${g}, ${b})`);
            $('#preview-label').text(`Red: ${r}, Green: ${g}, Blue: ${b}`);
            $('#redRange').val(r);
            $('#greenRange').val(g);
            $('#blueRange').val(b);
            if(send_data){
                $.get({
                    url: serverBaseURL + "setColor",
                    data : $.param({
                        r: r,
                        g: g,
                        b: b
                    }),
                    success: () => {},
                });
        }
        }

        $(document).ready(() => {
            refreshState();

            $('#toggle-switch-primary').change(() => {
                let lightValue = 0;
                if($('#toggle-switch-primary').is(':checked')) lightValue = 1;
                $.get({
                    url: serverBaseURL + "setLight",
                    data: $.param({
                        value: lightValue
                    }),
                    success: () => {}
                });
            });

            window.setInterval(refreshState, 5000);

            $('#neutral-black-btn').click(() =>{
                setColor(0, 0, 0, true);
            });
            $('#neutral-white-btn').click(() =>{
                setColor(255, 255, 255, true);
            });
            $('#neutral-light-gray-btn').click(() =>{
                setColor(211,211,211, true);
            });
            $('#neutral-dark-gray-btn').click(() =>{
                setColor(169,169,169, true);
            });
            $('#solid-red-btn').click(() =>{
                setColor(255,0,0, true);
            });
            $('#solid-green-btn').click(() =>{
                setColor(0,255,0, true);
            });
            $('#solid-blue-btn').click(() =>{
                setColor(0,0,255, true);
            });
            $('#solid-purple-btn').click(() =>{
                setColor(128,0,128, true);
            });
            $('#neon-pink-btn').click(() =>{
                setColor(255, 133, 153, true);
            });
            $('#neon-green-btn').click(() =>{
                setColor(118, 255, 54, true);
            });
            $('#neon-blue-btn').click(() =>{
                setColor(45, 101, 255, true);
            });
            $('#neon-purple-btn').click(() =>{
                setColor(172, 70, 255, true);
            });
            $('#redRange').on('input', () =>{
                refreshColors();
            });
            $('#greenRange').on('input', () =>{
                refreshColors();
            });
            $('#blueRange').on('input', () =>{
                refreshColors();
            });
        });
        function refreshColors()
        {
            setColor($('#redRange').val(), $('#greenRange').val(), $('#blueRange').val(), true);
        }


    </script>
</head>

<body>

<div id="center-container" class="container">
    <div class="row">
    <div class="col-sm-4"></div>
    <div id="light-toggle-container" class="col-sm-8">
        <h2>Toggle Primary Lighting</h2>
        <label class="switch">
            <input type="checkbox" id="toggle-switch-primary">
            <span class="slider round"></span>
        </label>
    </div>
    </div>
    <div class="row">
    <div class="col-sm-4">
        <h4>Preview the Color</h4>
        <div id="preview-container">
        </div>
        <p id="preview-label"></p>
    </div>
    <div class="col-sm-2"></div>
    <div class="col-sm-6">
        <h2>Adjust Color By RGB Values</h2>
        <div id="slider-container">
            <input type="range" min=0 max=255 class="range-slider" id="redRange">
            <input type="range" min=0 max=255 class="range-slider" id="greenRange">
            <input type="range" min=0 max=255 class="range-slider" id="blueRange">
        </div>
    </div>
    </div>
    <div class="row">
    <div class="col-sm-2"></div>
    <div class="col-sm-10">
    <h2>Or Use a Preset</h2>
    <div id="preset-container">
        <button class="accordion">Neutral Colors</button>
        <div class="panel">
        <div class="aligner">
            <button class="btn" id="neutral-black-btn">Black</button>
            <button class="btn" id="neutral-white-btn">White</button>
            <button class="btn" id="neutral-light-gray-btn">Light Gray</button>
            <button class="btn" id="neutral-dark-gray-btn">Dark Gray</button>
        </div>
        </div>
        <button class="accordion">Solid Colors</button>
        <div class="panel">
        <div class="aligner">
            <button class="btn" id="solid-red-btn">Red</button>
            <button class="btn" id="solid-green-btn">Green</button>
            <button class="btn" id="solid-blue-btn">Blue</button>
            <button class="btn" id="solid-purple-btn">Purple</button>
        </div>
        </div>
        <button class="accordion">Neon Colors</button>
        <div class="panel">
        <div class="aligner">
            <button class="btn" id="neon-pink-btn">Neon Pink</button>
            <button class="btn" id="neon-green-btn">Neon Green</button>
            <button class="btn" id="neon-blue-btn">Neon Light Blue</button>
            <button class="btn" id="neon-purple-btn">Neon Purple</button>
        </div>
        </div>
        </div>
    </div>
    </div>
</div>

<script>
    var acc = document.getElementsByClassName("accordion");
    var i;
    
    for (i = 0; i < acc.length; i++) {
      acc[i].addEventListener("click", function() {
        this.classList.toggle("active");
        var panel = this.nextElementSibling;
        if (panel.style.maxHeight) {
            panel.style.visibility = "hidden";
            panel.style.margin = "0px";
            panel.style.maxHeight = null;
          
        } else {
            panel.style.visibility = "visible";
            panel.style.margin = "15px";
            panel.style.maxHeight = panel.scrollHeight + "px";
            //panel.style.margin = "15px";
        } 
      });
    }
</script>

</body>

</html>

#include <WiFi.h>
#include <HTTPClient.h>
#include <ArduinoJson.h>
 
const char* ssid = "ssid";
const char* password =  "pword";

const char* serverURL = "http://<IP>:<port>/lighting/getState";

#define RGB_R 12
#define RGB_G 13
#define RGB_B 14

#define RELAY_PIN 5

// Refresh every 3 seconds
#define DELAY_TIME 500
 
void setup(){
  Serial.begin(115200);
  delay(3000);
  WiFi.begin(ssid, password);
 
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi..");
  }
 
  Serial.println(WiFi.localIP());

    pinMode(RGB_R, OUTPUT);
    pinMode(RGB_G, OUTPUT);
    pinMode(RGB_B, OUTPUT);
    ledcAttachPin(RGB_R, 1);
    ledcAttachPin(RGB_G, 2);
    ledcAttachPin(RGB_B, 3);
    ledcSetup(1, 12000, 8);
    ledcSetup(2, 12000, 8);
    ledcSetup(3, 12000, 8);

    pinMode(RELAY_PIN, OUTPUT);
 
}
 
void loop()
{
  if((WiFi.status() == WL_CONNECTED))
  {
    HTTPClient http;
    http.begin(serverURL);
    int code = http.GET();
    if(code > 0)
    {
      DynamicJsonDocument doc(1024);
      String payload = http.getString();
      Serial.printf("Code = %d\n", code);
      Serial.println(payload);
      deserializeJson(doc, payload);
      JsonObject obj = doc.as<JsonObject>();
      set_led_strip(obj[String("colors")][0], obj[String("colors")][1], obj[String("colors")][2]);
      set_relay(obj[String("toggleVal")]);
    }
    http.end();
    delay(DELAY_TIME);
  }
}

void set_led_strip(uint8_t r, uint8_t g, uint8_t b){
    ledcWrite(1, r);
    ledcWrite(2, g);
    ledcWrite(3, b);
}

void set_relay(bool val)
{
    digitalWrite(RELAY_PIN, !val);
}

var config = require("./config.js");
var mysql = require("mysql");
const express = require("express");
const url = require('url');
const router = express.Router();

var pool = mysql.createPool({
    host : config.mysql.host,
    user : config.mysql.user,
    password : config.mysql.password,
    database : config.mysql.database
});

router.get("/lighting/setColor", (req, res)=>{
    const queryObj = url.parse(req.url, true).query;
    const RGBLightId = config.light.RGBLight;
    pool.getConnection((err, conn)=>{
        conn.query(`UPDATE RGBLight SET RGB_value = ? WHERE light_id = ?`, 
        [JSON.stringify([queryObj.r, queryObj.g, queryObj.b]), RGBLightId], () => {
            conn.release();
            res.send("ok");
        });
    });
});

router.get("/lighting/setLight", (req, res)=>{
    const queryObj = url.parse(req.url, true).query;
    const mainLight = config.light.main;
    pool.getConnection((err, conn)=>{
        conn.query(`UPDATE Light SET state = ? WHERE light_id = ?`, 
        [queryObj.value, mainLight], () => {
            conn.release();
            res.send("ok");
        });
    });
});

router.get("/lighting/getState", (req, res)=>{
    const RGBLightId = config.light.RGBLight;
    const mainLight = config.light.main;
    var response = {
        colors : {}
    };
    pool.getConnection((err, conn)=>{
        if(err) console.log(err);
        conn.query(`SELECT RGB_value FROM SmartHome.Light LEFT JOIN SmartHome.RGBLight ON Light.light_id = RGBLight.light_id WHERE Light.light_id = ? LIMIT 1`, [RGBLightId], (err, rows) => {
            conn.release();
            if(err) console.log(err);
            var colorArr = JSON.parse(rows[0].RGB_value);
            response.colors.r = colorArr[0]; response.colors.g = colorArr[1];
                response.colors.b = colorArr[2]; 
        });
    });
    pool.getConnection((err, conn)=>{
        conn.query(`SELECT state FROM SmartHome.Light WHERE Light.light_id = ? LIMIT 1`, [mainLight], (err, rows) => {
            conn.release();
            response.toggleVal = Number(rows[0].state);
            res.send(response);
        });
    });
    
});

module.exports = router;

Credits

Evan Rust

122 projects • 1091 followers

IoT, web, and embedded systems enthusiast. Contact me for product reviews or custom project requests.

Smart Room Lighting with ESP32

Things used in this project

Hardware components

Software apps and online services

Story

Purpose

Hardware Needed

MySQL DB Setup

Node.JS Backend Webserver

Lighting Control Frontend

The ESP32 Program

Expanding the System

Schematics

Wiring

Code

webpage.html

server.js

ESP32 Code

light-control.js

config.js

Credits

Evan Rust

Comments

Embed the widget on your own site

Smart Room Lighting with ESP32

Smart Room Lighting with ESP32

Things used in this project

Hardware components

Software apps and online services

Story

Purpose

Hardware Needed

MySQL DB Setup

Node.JS Backend Webserver

Lighting Control Frontend

The ESP32 Program

Expanding the System

Schematics

Wiring

Code

webpage.html

server.js

ESP32 Code

light-control.js

config.js

Credits

Evan Rust

Comments

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