GMU:Designing Utopias: Theory and Practice/Selena Deger

07.12.22

Analog sound and ultrasonic distance sensor

https://wiki.keyestudio.com/KS0035_Microphone_Sound_Sensor_with_Potentiometer

Analog sound sensor includes a microphone sensor to detect ambient sounds and loudness of them. In some sources usage is recommended with an audio analyzer module(https://www.dfrobot.com/product-514.html) to differentiate different frequencies.

https://www.sparkfun.com/products/15569

Ultrasound distance sensor consists of a trigger and receiver parts, one is releasing ultrasonic waves and the other is receiving the reflected waves to calculate the distance from the duration of the bouncing time. The detection range is 2-40cm.

connecting to Arduino

Analogue sound is connected to the analog pin, while trigger and receiver pins of the ultrasound sensor are connected to two different digital pins.

To see the differences in the values, I put some track on the bluetooth speaker and moved it in front of the distance sensor.

File:sel_sound.mp4

#define echoPin 2 // attach pin D2 Arduino to pin Echo of HC-SR04
#define trigPin 3 //attach pin D3 Arduino to pin Trig of HC-SR04

int buzzer = 7;

// defines variables
long duration; // variable for the duration of sound wave travel
int distance; // variable for the distance measurement

void setup() {
  // put your setup code here, to run once:

  pinMode(trigPin, OUTPUT); // Sets the trigPin as an OUTPUT
  pinMode(echoPin, INPUT); // Sets the echoPin as an INPUT
  Serial.begin(9600);
}

void loop() {
  int val;

  val=analogRead(2);

  Serial.print("Loudness:");
  Serial.println(val,DEC);
  delay(100);

  // Clears the trigPin condition
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  // Sets the trigPin HIGH (ACTIVE) for 10 microseconds
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  // Reads the echoPin, returns the sound wave travel time in microseconds
  duration = pulseIn(echoPin, HIGH);
  // Calculating the distance
  distance = duration * 0.034 / 2; // Speed of sound wave divided by 2 (go and back)
  
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");

creating the loop

I have added a piezzo buzzer (+ 1K resistor) to the circuit to make the process of loudness detection more cyclical. I have followed this tutorial connecting it > https://surtrtech.com/2018/01/29/how-to-use-a-buzzer-piezo-speaker-with-arduino/

added the code a condition about the distance. When the distance is smaller than 10cm, buzzer starts to buzz with the mapped values also from the sound and distance sensor.

 if(distance<10) {
    long buzz = map(val, 0, 40, 1000, 5000);
    long del = map(distance, 2, 40, 100, 800);
    tone(buzzer, buzz); 
// tone() is the main function to use with a buzzer, it takes 2 or 3 parameters (buzzer pin, sound frequency, duration)
      delay(del);
  }
  else {
    tone(buzzer, 0);
  }

File:sel_buzzer.mp4

01.12.22

line tracking sensor

https://wiki.keyestudio.com/Ks0050_keyestudio_Line_Tracking_Sensor

Line tracking sensor is used for differentiating between black and white(either can be the backgorund/foreground) with the integrated infrared sensors(one emitting, one collecting). It is very dependent on the reflectiveness of the material/object therefore it is important to have a consistent and equal light source on the surface.

connecting to arduino

After following the instructions in the producer website, I have managed to get the first digital outputs from the sensor.

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To get different numbers from the sensor(other than hi/lo), I connected it to an analog input.

void setup()
{
  Serial.begin(9600);
}
void loop()
{


  Serial.println(analogRead(A0)); // print the data from the sensor


  delay(500);
}

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moving data to processing

Following this tutorial > https://www.arduino.cc/education/visualization-with-arduino-and-processing I have first uploaded this code snippet to the arduino

unsigned int ADCValue;
void setup(){
    Serial.begin(9600);
}

void loop(){

 int val = analogRead(0);
   val = map(val, 0, 300, 0, 255);
    Serial.println(val);
delay(50);
}

Lastly running different examples from the same tutorial on processing, resulted in different visualization of the black/white data retrieved from the sensor.