Published December 17, 2020 © CC BY-NC-SA

DIY Chameleon Lamp

An easy DIY lamp which can change its colour like a chameleon. Just show it a different colour & see the magic.

BeginnerFull instructions provided30 minutes6,270

Things used in this project

Hardware components

Adafruit NeoPixel Ring: WS2812 5050 RGB LED

DFRobot Gravity: TCS34725 RGB Color Sensor For Arduino

Arduino Nano R3

Breadboard (generic)

Jumper wires (generic)

LED Light Bulb, Frosted GLS

Software apps and online services

Arduino IDE

Hand tools and fabrication machines

Multitool, Screwdriver

Story

Have you ever think of making a lamp which can take any colour based on its environment?

Then this DIY lamp project is an answer to that. This is an easy DIY lamp which can change its colour based on your inputs & its made with the favourite controller of all; Arduino Nano. Drop a like if you find this Hackster project as a good resource.

Step 1: Gather the Material

All the material mentioned here is easily available in your local market as well as online stores.

Adafuit Neopixel Ring
TCS34725 RGB Sensor
Fused/Spare 15W LED Bulb Diffuser
Arduino Nano/Uno/Mega
BreadBoard
Jumper Cable

Step 2: Introduction

This project is a DIY method to replicate the colour changing power of a chameleon. For this, We will have to create an electronic circuit which can take input as colour & give output as the light of the same colour.

The most important material in this project is the RGB colour sensor TCS34725. This sensor has RGB and Clear light sensing elements. An IR blocking filter, the filter means you'll get much truer colour than most sensors since humans don't see IR. The sensor also has an incredible 3, 800, 000:1 dynamic range with adjustable integration time and gain so it is suited for use behind darkened glass.

We will be using an Arduino Nano board to take input from the sensor, one Adafruit Neopixel Ring to output the light of the same colour & one diffuser from an old fused LED bulb to diffuse the light.

Let's move to the circuit now.

Step 3: Making the Connections

There are few connections only, viz; (Refer to the connections from the circuit image)

Common Connections :

Connect GND of Arduino Nano to the side rail of the breadboard.
Connect 5V of Arduino Nano to the side rail of the breadboard.
Connect PWR of the LED ring & Vin of the TCS34725 sensor to the 5V side rail.
Connect GND of the LED ring & TCS34725 sensor to the GND side rail.

Sensor Connections :

Connect SDA of the sensor to pin A4 of Arduino nano.
Connect SCL of the sensor to pin A5 of Arduino nano.
Connect 3v3 of the sensor to pin 3v3 of Arduino nano.

LED ring Connections :

Connect IN of LED ring to pin D3 of Arduino nano.

Note: Double Check the connections before powering up the device.

Step 4: Taking Out the Diffuser

This step is a fun part, where you have to remove the diffuser cap of the fused LED bulb. There are several ways to do this :

Use a sharp tool & open the locks of the cap.
Drop the bulb from a considerable height few times, the cap will loosen up automatically. (I personally like this second option as its more fun to drop it)

Once the cap is out we can program our board & start playing.

Step 5: Let's Code It

This is an Arduino IDE sketch. You can use Arduino IDE or Fritzing to upload this code to the Arduino nano. Upload it & see the magic.

Step 6: Working

Code

Arduino Code

#include <Wire.h>
#include <Adafruit_TCS34725.h>
#include <Adafruit_NeoPixel.h>

#define NUMPIXELS 24
#define LED_PIN 3

#define debug false

byte gammatable[256];

Adafruit_TCS34725 tcs = Adafruit_TCS34725(TCS34725_INTEGRATIONTIME_50MS, TCS34725_GAIN_4X);
Adafruit_NeoPixel pixels = Adafruit_NeoPixel(NUMPIXELS, LED_PIN, NEO_GRB+NEO_KHZ800);

void setup() {
  if(debug){
    Serial.begin(115200);
  }
  tcs.begin();
  pixels.begin();
  for (int i = 0; i < 256; i++){
    float x = i;
    x /= 255;
    x = pow(x, 2.5);
    x *= 255;
    gammatable[i] = x;
  }
}

void loop(){
  float r, g, b;
  delay(60);
  tcs.getRGB(&r, &g, &b);
  if(debug){
    Serial.print("R: "); 
    Serial.print(int(r)); 
    Serial.print("\tG: "); 
    Serial.print(int(g)); 
    Serial.print("\tB: "); 
    Serial.println(int(b));
  }
  for(int i = 0; i < NUMPIXELS; i++){
    pixels.setPixelColor(i, pixels.Color(gammatable[(int)r], gammatable[(int)g], gammatable[(int)b]));
  }
  pixels.show();
}