Scopul proiectului este realizarea unui decibelmetru, un aparat capabil sa capteze intensitatea sunetelor si sa prezinte utilizatorului informatia atat digital prin intermediul unui ecran, cat si analogic folosind un ledbar.

Utilizam un modul microfon pentru captarea sunetului si o placuta Arduino Uno R3 pentru procesarea lui, in functie de intensitatea sunetului se va aprinde secvential un ansamblu de leduri si se va transmite valoarea in dB unui ecran LCD.

Componente utilizate:

• Arduino Uno R3
• Breadboard
• LEDs
• Cabluri
• Rezistente
• Modul microfon
• Display LCD

Schema hardware:

#include <Wire.h>
#include <LiquidCrystal_I2C.h> 
LiquidCrystal_I2C lcd = LiquidCrystal_I2C(0x27, 16, 2);
 
const int sampleWindow = 50;                              
unsigned int sample;
 
#define SENSOR_PIN A0
#define PIN_QUIET1 3
#define PIN_QUIET2 4
#define PIN_MODERATE1 5
#define PIN_MODERATE2 6
#define PIN_LOUD1 7
#define PIN_LOUD2 8
 
void setup ()  
{   
  pinMode (SENSOR_PIN, INPUT);  
  pinMode(PIN_QUIET1, OUTPUT);
  pinMode(PIN_QUIET2, OUTPUT);
  pinMode(PIN_MODERATE1, OUTPUT);
  pinMode(PIN_MODERATE2, OUTPUT);
  pinMode(PIN_LOUD1, OUTPUT); 
  pinMode(PIN_LOUD2, OUTPUT); 
 
  digitalWrite(PIN_QUIET1, LOW);
  digitalWrite(PIN_QUIET2, LOW);
  digitalWrite(PIN_MODERATE1, LOW);
  digitalWrite(PIN_MODERATE2, LOW);
  digitalWrite(PIN_LOUD1, LOW);
  digitalWrite(PIN_LOUD2, LOW);
 
 
 
  lcd.backlight();
  delay(20);
  lcd.init();
}  
 
 
void loop ()  
{ 
   unsigned long startMillis= millis();                   
   float peakToPeak = 0;                                 
 
   unsigned int signalMax = 0;                            
   unsigned int signalMin = 1024;                         
 
 
   while (millis() - startMillis < sampleWindow)
   {
      sample = analogRead(SENSOR_PIN);                   
      if (sample < 1024)                                  
      {
         if (sample > signalMax)
         {
            signalMax = sample;                           
         }
         else if (sample < signalMin)
         {
            signalMin = sample;                           
         }
      }
   }
 
   peakToPeak = signalMax - signalMin;                    
   int db = map(peakToPeak,0,500,28,85);             
  lcd.setCursor(0, 0);
  lcd.print("Loudness: ");
  lcd.print(db);
  lcd.print("dB");
  if(db <= 30){
    digitalWrite(PIN_QUIET1, LOW);
    digitalWrite(PIN_QUIET2, LOW);
    digitalWrite(PIN_MODERATE1, LOW);
    digitalWrite(PIN_MODERATE2, LOW);
    digitalWrite(PIN_LOUD1, LOW);
    digitalWrite(PIN_LOUD2, LOW);
  }
 
  else if (db > 30 && db < 35)
  {
    digitalWrite(PIN_QUIET1, HIGH);
    digitalWrite(PIN_QUIET2, LOW);
    digitalWrite(PIN_MODERATE1, LOW);
    digitalWrite(PIN_MODERATE2, LOW);
    digitalWrite(PIN_LOUD1, LOW);
    digitalWrite(PIN_LOUD2, LOW);
  }
 
  else if (db >= 35 && db < 40)
  {
    digitalWrite(PIN_QUIET1, HIGH);
    digitalWrite(PIN_QUIET2, HIGH);
    digitalWrite(PIN_MODERATE1, LOW);
    digitalWrite(PIN_MODERATE2, LOW);
    digitalWrite(PIN_LOUD1, LOW);
    digitalWrite(PIN_LOUD2, LOW);
  }
 
  else if (db >= 40 && db < 45)
  {
    digitalWrite(PIN_QUIET1, HIGH);
    digitalWrite(PIN_QUIET2, HIGH);
    digitalWrite(PIN_MODERATE1, HIGH);
    digitalWrite(PIN_MODERATE2, LOW);
    digitalWrite(PIN_LOUD1, LOW);
    digitalWrite(PIN_LOUD2, LOW);
  }
 
  else if (db >= 45 && db < 50)
  {
    digitalWrite(PIN_QUIET1, HIGH);
    digitalWrite(PIN_QUIET2, HIGH);
    digitalWrite(PIN_MODERATE1, HIGH);
    digitalWrite(PIN_MODERATE2, HIGH);
    digitalWrite(PIN_LOUD1, LOW);
    digitalWrite(PIN_LOUD2, LOW);
  }
  else if (db >= 50 && db < 60)
  {
    digitalWrite(PIN_QUIET1, HIGH);
    digitalWrite(PIN_QUIET2, HIGH);
    digitalWrite(PIN_MODERATE1, HIGH);
    digitalWrite(PIN_MODERATE2, HIGH);
    digitalWrite(PIN_LOUD1, HIGH);
    digitalWrite(PIN_LOUD2, LOW);
 
  }
 
  else if (db >= 65)
  {
    digitalWrite(PIN_QUIET1, HIGH);
    digitalWrite(PIN_QUIET2, HIGH);
    digitalWrite(PIN_MODERATE1, HIGH);
    digitalWrite(PIN_MODERATE2, HIGH);
    digitalWrite(PIN_LOUD1, HIGH);
    digitalWrite(PIN_LOUD2, HIGH);
 
  }
 
   delay(200); 
   lcd.clear();
}

Dezvoltat folosind Arduino IDE, am utilizat “Wire.h” si “LiquidCrystal_I2C” pentru interactiunea cu ecranul LCD.

Realizarea unui decibelmetru functional, usor de folosit, capabil sa lucreze in intervale de sunet uzuale (30dB-65dB).

Finished initial doc. (5/6/2023)
Added hardware schematic and source code of the project. (5/26/2023)