Introduction: Clap Activated Light Switch

This simple device allows you to make any common light switch clap activated.

Step 1: Acquire the Components

The components needed can be purchased most easily from Amazon

  • 1 Arduino Uno with leads and power/sync cable
  • 1 microphone
  • 1 180 degrees hi torque micro servo
  • 6 jumper leads
  • 1 power bank
  • 1 sheet of foem core
  • 1 small sheet of thin metal or plastic
  • 1 bread board
  • A 1 inch diameter wooden dowel rod 2 inches long
  • 1 heavy duty paper clip

Step 2: Program and Connect Arduino

With Arduino installed on your computer use the following code to program your arduino:

#include Servo

lightSwitch;

int sensor = 0;

boolean state = false;

int tolerance = 1000;

int counter = 0; int count = 3;

void setup() { Serial.begin(9600);

lightSwitch.attach(5); lightSwitch.write(0);}

void loop() { int raw = analogRead(sensor);

Serial.println(raw);

if (raw > tolerance){counter++;}

else{counter = 0;}

if (counter >= count)

{ if (state == false){ lightsOn();

state = true; }

else if (state == true)

{ lightsOff(); state = false; }

delay(2000); }

}

void lightsOn(){ lightSwitch.write(180); }

void lightsOff(){ lightSwitch.write(0); }

Connect the three leads going to the servo into the ground, "Vin" and #6 pins on the Arduino.

Plug the microphone into the breadboard and connect the 3 leads into another ground, "5v", and A0 pins on the Arduino.

Plug the power bank into the Arduino.

Step 3: Light Switch Attachment

Mark the metal or plastic plate and cut it to size.

Use a light switch to mark where to drill the hole for the 2 screws and and where to cut the slot for the switch and cut.

Use the piece of wood to make two legs that will hold the servo off the plate. I used hot glue to attach the servo to the wood.

Cut the foam core to build a box around the Arduino-microphone set up for protection.

Drill through the plate into the 2 wooden legs to connect the servo to the plate.

Mount the device to the light switch.

Straighten the paper clip and make a loop at one end to go around the switch. At the other end bend the clip so that it attaches the the servo arm.

Step 4: Try It Out!

With everything connected, clap and the switch should be flipped. In some cases you may have to clap more than once to activate it.