Project 2 - Measuring the distance of an object using ultrasonic sensor and also smoothen the sensor data using moving average filter
// C++ code
//
#define WINDOW_SIZE 5
#include <LiquidCrystal.h>
LiquidCrystal lcd(12,11,5,4,3,2);
float duration;
float sigpin = 13;
int INDEX = 0;
float VALUE = 0;
int SUM = 0;
int READINGS[WINDOW_SIZE];
int AVERAGED = 0;
void setup(){
lcd.begin(16,2);
lcd.setCursor(0,0);
pinMode(sigpin, INPUT);
lcd.setCursor(0,0);
lcd.print("Distance: ");
Serial.begin(9600);
}
void loop() {
pinMode(sigpin, OUTPUT);
digitalWrite(sigpin, HIGH);
delayMicroseconds(10);
digitalWrite(sigpin, LOW);
pinMode(sigpin, INPUT);
duration = pulseIn(sigpin, HIGH);
VALUE = (duration / 2.0) / 74.0;
//Moving Avg Filter
SUM = SUM - READINGS[INDEX];
READINGS[INDEX] = VALUE;
SUM = SUM + VALUE;
INDEX = (INDEX+1) % WINDOW_SIZE;
AVERAGED = SUM / WINDOW_SIZE;
lcd.setCursor(0,1);
lcd.print(VALUE);
lcd.print(" inches");
delay(50);
//Serial.print(inches);
Serial.print(VALUE);
Serial.print(",");
Serial.println(AVERAGED);
}