#include <Servo.h>
const int trig = 9;  
const int echo = 10;  
const int servoPin = 11; 

Servo binLid;            
const int openAngle = 90;  
const int closeAngle = 0;  
const int thresholdDistance = 50; 
void setup() {
    Serial.begin(9600);
    pinMode(trig, OUTPUT);
    pinMode(echo, INPUT);
    binLid.attach(servoPin); 
    binLid.write(closeAngle); 
}

void loop() {
    long duration, distance;
    digitalWrite(trig, LOW);
    delayMicroseconds(2);
    digitalWrite(trig, HIGH);
    delayMicroseconds(10);
    digitalWrite(trig, LOW);

    duration = pulseIn(echo, HIGH);
    distance = (duration * 0.034 / 2);  
    Serial.print("Distance: ");
    Serial.println(distance);
    if (distance <= thresholdDistance) {
        binLid.write(openAngle); 
    } else {
        binLid.write(closeAngle); 
    }

    delay(500); 
}