IR Proximity Sensor

Using Arduino Sensors
1

Hi I would like to ask why i always get same value distance even if the object is near or far as long as it is detected by the IR sensor? TIA for the reply. :slight_smile:

2

Based on the infromation provided, it is either a programming problem or a hardware setup problem.

3

This is my code:

#include<Servo.h>

int proxSensorPin= A0; // Proximity sensor pin
int proxSensorValue= 0; // variable to store the value coming from the sensor

int irSensorPin = A1; //IR sensor pin
int irSensorValue;

Servo servo1;

void setup() {
// declare the ledPin as an OUTPUT:
Serial.begin(9600);

servo1.attach(11);
}

void loop() {
// read the value from the sensor:
proxSensorValue= analogRead(proxSensorPin);
irSensorValue= analogRead(irSensorPin);
Serial.print("\nPlasticsensor = ");
Serial.println(proxSensorValue);
Serial.print("Papersensor = ");
Serial.println(irSensorValue);
// turn the ledPin on if triggered
//
if (proxSensorValue <200){
Serial.println("Plastic Detected");
servo1.write(20);
}
else if (irSensorValue <100){
Serial.println("Paper Detected");
servo1.write(180);

}
else{
Serial.print("\nNo Item Detected");
servo1.write(100);
}

delay(1000);
}

4

Although the Arduino has multiple input pins, it only has one A/D converter. When reading multiple analog pins, you need to pre-read and throw away the value read to ensure the sample circuit has acquired and settled on the new analog pin.

junkread= analogRead(proxSensorPin);
proxSensorValue= analogRead(proxSensorPin);
junkread= analogRead(irSensorPin);
irSensorValue= analogRead(irSensorPin);

It could be a hardware problem as well.

5

Thanks for replying sir it will really help me in my project but i want to ask where to put those lines you replied to me :slight_smile:

6

Put them where you have the analogRead instructions.

Change

proxSensorValue= analogRead(proxSensorPin);
irSensorValue= analogRead(irSensorPin);

to

junkread= analogRead(proxSensorPin);
proxSensorValue= analogRead(proxSensorPin);
junkread= analogRead(irSensorPin);
irSensorValue= analogRead(irSensorPin);

Don't forget to declare junk_read as a local int variable.