Secret Clap Door Lock

A door lock which opens only when a particular pattern of claps are detected. An Arduino based system is created which hears the pattern of claps and compares it with the saved pattern. If both matches, the lock opens.

The pattern of claps is detected using a sound sensor module. It gives a LOW(False) when a clap is detected. I am using the time component to detect the pattern. The amount of time duration between two successive claps is measured and hence a pattern is formed. This pattern is then compared to the saved correct pattern.

Here I am using a LED instead of a lock for simplicity. A servo motor in the form of lock can be used. The LED glows when the pattern matches the correct pattern. If the incorrect pattern is detected, the LED remains dim and the program resets after 3 seconds and gets ready to take new pattern input.

Security is a major concern in our day to day life, and digital locks have become an important part of these security systems. This a simple example of the same.

Components :

• Arduino Uno
• Bread Board
• Resistor (10K)
• LED
• Jumper Wires
• Sound sensor module

Connections :

Code:

  
int motor_input1=11;
int motor_input2=10;
int motor_input3=5;
int motor_input4=6;
int L=2;
int R=3;

void setup() {
  pinMode(L,INPUT);
  pinMode(R,INPUT);
  Serial.begin(9600);
  pinMode(motor_input1,OUTPUT);
  pinMode(motor_input2,OUTPUT);
  pinMode(motor_input3,OUTPUT);
  pinMode(motor_input4,OUTPUT);
}

void loop() {
  if((digitalRead(R)==true)&&(digitalRead(L)==false)) {
    Serial.println("LEFT");
    analogWrite(motor_input1,200);
    analogWrite(motor_input2,0);
    analogWrite(motor_input3,200);
    analogWrite(motor_input4,0);
    delay(10);
  }
  else
  if((digitalRead(L)==true)&&(digitalRead(R)==false)) {
    Serial.println("RIGHT");
    analogWrite(motor_input3,0);
    analogWrite(motor_input4,200);
    analogWrite(motor_input1,0);
    analogWrite(motor_input2,200);
    delay(10);
  }
  else { 
    Serial.println("Straight");
    analogWrite(motor_input1,120);
    analogWrite(motor_input2,0);
    analogWrite(motor_input3,0);
    analogWrite(motor_input4,120);
    delay(10);
  }
  
}