// Obstacles Detection  (( Collision Prevention System ))
#include <LiquidCrystal.h>
const int trigPin = 3; 
const int echoPin = 2; 
const int GledPin = 12;
const int RledPin = 13;
LiquidCrystal lcd(7, 6, 5, 4, 9, 8);
const int buzzerPin = 10;
void setup() {
  // Initialize the LCD
  lcd.begin(16, 2);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(GledPin, OUTPUT);
  pinMode(RledPin, OUTPUT);
  pinMode(buzzerPin, OUTPUT);
  noTone(buzzerPin); // Turn off the buzzer initially
}

void loop() {
  // Variables to store the duration and distance
  long duration;
  int distance;

  // Trigger the ultrasonic sensor to measure distance
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin, HIGH);   // Measure the echo duration
  distance = duration / 29 / 2;// Calculate the distance in centimeters

  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Distance: ");
  lcd.print(distance);
  lcd.print(" cm");

  // Increase volume of the beep sensor as object gets closer
  if (distance < 100) { // Adjust this threshold as needed
    int toneFreq = map(distance, 0, 20, 200, 2000); 
    // Map distance to frequency
    tone(buzzerPin, toneFreq); // Play tone with increased frequency
    digitalWrite(RledPin, HIGH);
    digitalWrite(GledPin, LOW);
    lcd.setCursor(0, 1);
    lcd.print("Please STOP Now!");
  } else {
    noTone(buzzerPin); // Turn off the buzzer if no object is close
    digitalWrite(RledPin, LOW);
    digitalWrite(GledPin, HIGH);
    lcd.setCursor(0, 1);
    lcd.print("You can Move Now");

  }
  delay(100);
}











































// To create a Arduino Uno program (commonly referred to as a sketch) 
// that uses an ultrasonic sensor to measure distance, 
// displays the distance on a 4-bit LCD, and increases 
// the volume of a beep sensor as an object gets closer 
// to the ultrasonic sensor, you can follow the steps below. 
// This example assumes you have a 4-bit LCD and a beep sensor
//  (like a piezo buzzer) connected to your Arduino Uno.


// ### Materials Needed:
// 1. Arduino Uno board
// 2. Ultrasonic Sensor (e.g., HC-SR04)
// 3. 4-bit LCD display (e.g., 16x2 LCD)
// 4. Beep sensor (e.g., Piezo Buzzer)
// 5. Jumper wires
// ~~~~~~~~~~~~~~~~
      // Sketch
// ~~~~~~~~~~~~~~~~~~
// ### Wiring:
// 1. Connect the VCC and GND of the ultrasonic sensor
//  to 5V and GND on the Arduino, respectively.
// 2. Connect the Trig pin of the ultrasonic sensor to
//  pin 2 on the Arduino.
// 3. Connect the Echo pin of the ultrasonic sensor to
//  pin 3 on the Arduino.
// 4. Connect the VCC and GND of the 4-bit LCD to 5V
//  and GND on the Arduino, respectively.
// 5. Connect the RS, EN, D4, D5, D6, and D7 pins of 
// the LCD to pins 7, 6, 5, 4, 9, and 8 on the Arduino, respectively.
// 6. Connect the positive (anode) lead of the beep sensor
//  (Piezo Buzzer) to pin 10 on the Arduino.
// 7. Connect the negative (cathode) lead of the beep sensor
//  to GND on the Arduino.

// Make sure you have the necessary libraries installed, 
// such as the "LiquidCrystal" library for the LCD. 
// You can install it through the Arduino Library Manager.

// Upload the sketch to your Arduino Uno, 
// and you should be able to measure distances 
// with the ultrasonic sensor, display them on the LCD, 
// and increase the volume of the beep sensor as objects 
// get closer to the ultrasonic sensor. Adjust the
//  distance threshold and tone frequency mapping to 
//  suit your specific needs.