Arduino Distance Approximator

1
2// -------------------------Distance Approximater using Arudino Ultrasonic  Sensor and LEDs----------------
3// By : Gurneet Singh
4// Materials Used:
5//  1. 10 LEDS
6// 2. Ultrsonic Sensor
7// 3. Resistors
8// 4. Jumper Wires and  Breadboards
9
10#define echoPin 2 // D2 to Echo
11#define trigPin 3 //D3 to  trig
12int led_pins[] = {13,12,11,10,9,8,7,6,5,4}; // Array of 10Pins as output  to LED
13int high_pins = 0; // Count of High/On Pins
14int low_pins = 10; // Count  of Low/Off Pins
15long duration; // variable for the duration of sound wave travel
16int  distance; // variable for the distance measurement
17
18void setup() {
19  pinMode(trigPin,  OUTPUT); // Sets the trigPin as an OUTPUT
20  pinMode(echoPin, INPUT); // Sets  the echoPin as an INPUT
21  for(int i=0;i<9;i++){
22    pinMode(led_pins[i],OUTPUT);  // Sets all the LED pins as OUTPUT
23  }
24  Serial.begin(9600); 
25  Serial.println("Ultrasonic  Sensor HC-SR04 and LED Distance Apporximater");
26}
27void loop() {
28  digitalWrite(trigPin,  LOW);
29  digitalWrite(trigPin, HIGH);
30  digitalWrite(trigPin, LOW);
31  duration  = pulseIn(echoPin, HIGH);
32  distance = duration * 0.034 / 2;  // Distance formula  
33  Serial.print("Distance: ");
34  Serial.print(distance);
35  Serial.println("  cm"); 
36
37  // Below are a lot of IF-ELSE which decide on the basis of the  distance, how much LEDs need to glow
38  if(distance > 0 && distance <= 5){
39    high_pins = 10;
40    }
41  else if(distance <= 9){
42    high_pins = 9;
43    }   
44  else if(distance <= 14){
45    high_pins = 8;
46    }   
47  else  if(distance<=18){
48    high_pins = 7;
49    }
50    else if(distance<=22){
51    high_pins = 6;
52    }
53    else if(distance<=26){
54    high_pins = 5;
55    }
56    else if(distance<=30){
57    high_pins = 4;
58    }
59    else if(distance<=34){
60    high_pins =3;
61    }
62    else if(distance <=38){
63      high_pins = 2;}
64     else if(distance <=43){
65     high_pins = 1;
66     }
67     else {
68      high_pins = 0;
69      }
70    for(int i=0;i<=high_pins;i++){
71      digitalWrite(led_pins[i],HIGH);   // Loop to set the led pins to HIGH
72      }
73     for(int j=high_pins;j<11;j++){
74      digitalWrite(led_pins[j],LOW);   // Loop to set the led pins to LOW
75      }
76}
77