## Introduction: Ultrasonic Sensor Curtain Detector

Use the ultrasonic sensor and Arduino to sense if the curtain is pulled, remind me to pull the curtain before going to bed.

• 1 X Arduino Leonardo
• 1 X ultrasonic sensor
• 3 X led light
• 1 X power-bank
• 1 X USB Cable
• Hook-up wires
• 1 X Box that is at least 20cm*12cm*7cm
• 1 X 21cm*17cm paper

## Step 2: Code

int ardublockUltrasonicSensorCodeAutoGeneratedReturnCM(int trigPin, int echoPin){

long duration;

pinMode(trigPin, OUTPUT);

pinMode(echoPin, INPUT); digitalWrite(trigPin, LOW);

delayMicroseconds(2);

digitalWrite(trigPin, HIGH);

delayMicroseconds(20);

digitalWrite(trigPin, LOW);

duration = pulseIn(echoPin, HIGH);

duration = duration / 59;

if ((duration < 2) || (duration > 300)) return false;

return duration;

}

void setup() { pinMode( 11 , OUTPUT);

pinMode( 12 , OUTPUT);

pinMode( 13 , OUTPUT);

digitalWrite( 6 , LOW );

digitalWrite( 11 , HIGH );

digitalWrite( 12 , HIGH );

digitalWrite( 13 , HIGH );

}

void loop() { if (( ( 10.0 ) > ( ardublockUltrasonicSensorCodeAutoGeneratedReturnCM( 6 , 7 ) ) )) { digitalWrite( 12 , LOW ); // you can change the number depends on the distance to the curtain

digitalWrite( 13 , LOW );

digitalWrite( 11 , LOW ); }

else {

digitalWrite( 11 , HIGH );

digitalWrite( 12 , HIGH );

digitalWrite( 13 , HIGH ); } }

## Step 3: Making a Case

Cut a 5*2 cm hole in front of the box

Cut a 6*3 cm hole above the box

Put in the Arduino and Power-bank

The sensor need to be align to the hole in front and the LEDs need to be align to the hole above the box

Roll the paper and put it in the hole above the box