IR sensor with Arduino for restaurant parking - arduino

Question

I have problem in the code logic, I did not find any solution.
My doubt is I'm using two IR sensor interface with Arduino, so when car is passing 1st sensor and 2nd sensor then I'm sending the data that car is passed. That is fine but whenever car1 is passing 1st sensor and another car, say car2 is in 2nd sensor, then also flag is becoming 1, that is true but I don't want that.
How to code this so that car should pass two sensors? If car 1 is in sensor 1 and car 2 is in sensor 2 than flag should not be 1.
Please find the code below:
#include<avr/wdt.h>
#define DISTANCE 100
const int trigPin1 = 7;
const int echoPin1 = 6;
const int trigPin2 = 5;
const int echoPin2 = 4;
int MOVE_FLAG = 0;
void setup() {
// initialize serial communication:
Serial.begin(9600);
MOVE_FLAG = 0;
wdt_enable(WDTO_8S);
}
void loop()
{
// establish variables for duration of the ping,
// and the distance result in inches and centimeters:
long duration1, duration2, inches1, inches2, cm1, cm2;
// The sensor is triggered by a HIGH pulse of 10 or more microseconds.
// Give a short LOW pulse beforehand to ensure a clean HIGH pulse:
pinMode(trigPin1, OUTPUT);
digitalWrite(trigPin1, LOW);
delayMicroseconds(2);
digitalWrite(trigPin1, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin1, LOW);
// Read the signal from the sensor: a HIGH pulse whose
// duration is the time (in microseconds) from the sending
// of the ping to the reception of its echo off of an object.
pinMode(echoPin1, INPUT);
duration1 = pulseIn(echoPin1, HIGH);
inches1 = microsecondsToInches(duration1);
cm1 = microsecondsToCentimeters(duration1);
delay(10);
pinMode(trigPin2, OUTPUT);
digitalWrite(trigPin2, LOW);
delayMicroseconds(2);
digitalWrite(trigPin2, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin2, LOW);
pinMode(echoPin2, INPUT);
duration2 = pulseIn(echoPin2, HIGH);
// convert the time into a distance
inches2 = microsecondsToInches(duration2);
cm2 = microsecondsToCentimeters(duration2);
if(cm1 <= DISTANCE && cm2 <= DISTANCE && MOVE_FLAG == 0)
{
Serial.println("3");
MOVE_FLAG = 1;
}
if (cm1 > DISTANCE && cm2 > DISTANCE && MOVE_FLAG == 1)
{
MOVE_FLAG = 0;
delay(500);
}
delay(50);
wdt_reset();
}
long microsecondsToInches(long microseconds)
{
return microseconds / 74 / 2;
}
long microsecondsToCentimeters(long microseconds)
{
return microseconds / 29 / 2;
}

Answer 1

Two motion sensors are inadequate to accomplish what you described. Without video or something similar, there's no way for you to know whether Car 1 triggered the sensor or Car 2 triggered the sensor.
I suggest you re-think your approach to solving the problem. You might want to look at other parking lot projects people have created and posted on the Internet. Do a Google search for "Arduino Parking Lot" or something similar.