Hello, This time I will show an application of the infrared sensor module with Arduino.

This module (composed of a pair of LEDs, a infrared transmitter and a receiver and an IC that generates a frequency modulated) is generally used to detect obstacles in robots.

This module has some advantages over a simple LED emitting LEDs with a photodetector. The principal, in this case is that the emission frequency is modulated, preventing ambient light makes the receiver detect the wrong signal. Also, the construction module that facilitates interconnection and didactic use with the Arduino.

Step 1: Materials

- An Arduino board

- A sensor shield board

- 3 infrared sensor modules

- A standard servomotor

- A Styrofoam ball

- wires

Step 2: Mounting

Cut the Styrofoam ball to hold the arm of the servomotor, paint the Styrofoam ball in the shape of an eye, fit the servo arm in the eye and fit them into the servo.

Step 3: Mounting the Shield and Connecting Sensors

Mounting the Shield in Arduino, install the sensors with the aid of wires.

Note: The receiver module has 4 pins.

- A 5V

- 1 GND

- 1 OUT

- Enable (works to enable the module when it is without the jumper)

* Be careful not to inveter wires.

How to connect the wires:

Shield -> Sensors

pin 12 -> left sensor

pin 11 -> center sensor

pin 10 -> right sensor

Step 4: Mounting the Servo and Programing

After the sensors installed, install the servo on pin 9 of the shield, programming and testing.

The eye works as follows: to detect an object in front of each sensor (up to 40 cm, adjustable), the sensor changes state at the exit from Hi to Lo (of 5volts to zero) then the Arduino realize that there was a change state in one of its ports so, according to the software, the servomotor to rotate the eye to the preset position.

This was an application of the didactic use of infrared sensors. Many other applications are possible. The limit is your imagination. Hope you enjoy.

Software:

#include <Servo.h> // include servo library
Servo pescoco; // create servo object to control a servo
int pos =0;
int irdireita = 10;
int iresquerda = 12;
int ircentro = 11;
int tempo = 50;

void setup (){
pescoco.attach(9); // attaches the servo on pin 9 to the servo object
pinMode (irdireita, INPUT); // set pin irdireita (pin10) as input
pinMode (iresquerda, INPUT); // set pin iresquerda (pin12) as input
pinMode (ircentro, INPUT); // set pin ircentro (pin11) as input
}
void loop(){
int valdireita = digitalRead (irdireita);
int valesquerda = digitalRead (iresquerda);
int valcentro = digitalRead (ircentro);

if (valdireita == LOW){
pescoco.write(180);
pos = (180);
delay (tempo);
}
else if(valesquerda == LOW){
pescoco.write (0);
pos =(0);
delay (tempo);
}
else if (valcentro == LOW){
pescoco.write (90);
pos = (90);
delay (tempo);
}
else {
pescoco.write (pos);
delay (tempo);
}
}