Published September 19, 2018 © LGPL

Eye Motion Tracking Using Infrared Sensor

Use an infrared sensor to sense eye movements and control an LED.

IntermediateFull instructions provided5 hours42,565

Things used in this project

Hardware components

SparkFun Arduino Pro Mini 328 - 5V/16MHz

Adafruit LiIon/LiPoly Backpack Add-On for Pro Trinket/ItsyBitsy

NeoPixel strip

QTR-1A Reflectance Sensor

3.7 V LiPo Battery

Software apps and online services

Arduino IDE

Story

I used an infrared sensor to sense eye movements and control the LED.

NeoPixel LED Eye Ball

NeoPixel LED tape is used. LED is 68 unit.

LED is fixed to the bowl with double-sided tape and wired in the following order.

Eye Motion Tracking

Schematics

Sensor

I used two sensors QTR - 1A for eye tracking. QTR - 1A are placed on a plastic sheet at a distance of about the width of the eye.

The sensor part and the microcontroller part were fixed to the eyeglasses with a clip respectively.

1 / 2

Arduino Code

When the iris approaches one sensor, the reflected light decreases and the sensor value increases. Conversely, when the iris moves away, the reflected light increases and the sensor value of the photo reflector decreases.

The right and left movement of the pupil of the LED eyeball senses the increase and decrease of one sensor value and controls it.

When blinking, both sensor values decrease, so if the two sensor values decrease simultaneously, the eyelids of the LED eyeball will go down.

#include <QTRSensors.h>
#include <Adafruit_NeoPixel.h>
#define NUM_SENSORS             2  // number of sensors used
#define NUM_SAMPLES_PER_SENSOR  10  // averaging
#define EMITTER_PIN             QTR_NO_EMITTER_PIN  
int iniSensorValL, sensorValL;
int iniSensorValR, sensorValR;
#define PIN A3
Adafruit_NeoPixel led = Adafruit_NeoPixel(68, PIN, NEO_GRB + NEO_KHZ800);
int blackNum = 24;
int pupilNum = 12;
uint32_t color;
int brightness = 40;
byte eyeColor;
int LR =7;
boolean lid = false;
int cnt = 0;
//Black eye L&R animation
int blackLED[15][24] = {{12,32,35,55,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68},
                       {12,13,31,36,54,55,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68},
                       {11,13,14,30,37,53,54,56,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68},
                       {10,11,14,15,29,38,52,53,56,57,68,68,68,68,68,68,68,68,68,68,68,68,68,68},
                       { 9,10,11,12,15,16,28,33,34,39,51,52,55,56,57,58,68,68,68,68,68,68,68,68},
                       { 0, 8, 9,10,11,12,13,16,17,27,32,35,40,50,51,54,55,56,57,58,59,67,68,68},
                       { 0, 1, 7, 8, 9,10,13,14,17,18,26,31,36,41,49,50,53,54,57,58,59,60,66,67},
                       { 1, 2, 6, 7, 8, 9,14,15,18,19,25,30,37,42,48,49,52,53,58,59,60,61,65,66},
                       { 2, 3, 5, 6, 7, 8,15,16,19,20,24,29,38,43,47,48,51,52,59,60,61,62,64,65},
                       { 3, 4, 5, 6, 7,16,17,20,21,23,28,39,44,46,47,50,51,60,61,62,63,64,68,68},
                       { 4, 5, 6,17,18,21,22,27,40,45,46,49,50,61,62,63,68,68,68,68,68,68,68,68},
                       { 4, 5,18,19,26,41,48,49,62,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68},
                       { 4,19,20,25,42,47,48,63,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68},
                       {20,21,24,43,46,47,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68},
                       {21,23,44,46,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68,68}};
//pupil L&R animation
int pupilLED[15][12] = {{33,34,68,68,68,68,68,68,68,68,68,68},
                       {32,33,34,35,68,68,68,68,68,68,68,68},
                       {12,31,32,33,34,35,36,55,68,68,68,68},
                       {12,13,30,31,32,33,34,35,36,37,54,55},
                       {13,14,29,30,31,32,35,36,37,38,53,54},
                       {14,15,28,29,30,31,36,37,38,39,52,53},
                       {15,16,27,28,29,30,37,38,39,40,51,52},
                       {16,17,26,27,28,29,38,39,40,41,50,51},
                       {17,18,25,26,27,28,39,40,41,42,49,50},
                       {18,19,24,25,26,27,40,41,42,43,48,49},
                       {19,20,23,24,25,26,41,42,43,44,47,48},
                       {20,21,22,23,24,25,42,43,44,45,46,47},
                       {21,22,23,24,43,44,45,46,68,68,68,68},
                       {22,23,44,45,68,68,68,68,68,68,68,68},
                       {22,45,68,68,68,68,68,68,68,68,68,68}};
//Blink animation
int eyelid = 0;
int eyelidNum[8] = {0,4,8,16,24,34,44,56};
int eyelidLED[56] = {64,65,66,67,58,59,60,61,56,57,62,63,49,50,51,52,47,48,53,54,38,39,40,41,46,55,36,37,42,43,26,27,28,29,35,44,24,25,30,31,15,16,17,18,34,45,23,32,13,14,19,20,6,7,8,9};
QTRSensorsAnalog qtra((unsigned char[]) {0, 1}, NUM_SENSORS, NUM_SAMPLES_PER_SENSOR, EMITTER_PIN);
unsigned int sensorValues[NUM_SENSORS];
void blink(int eyelid, int LR) {
 if (eyelid != 8){
   //Pewter
   for(uint16_t i=0; i<led.numPixels(); i++) {
     led.setPixelColor(i, led.Color(66, 66, 66));
   }
   //Black eye
   for(uint16_t i=0; i<blackNum; i++) {
     led.setPixelColor(blackLED[LR][i], color);
   }
   //pupil
   for(uint16_t i=0; i<pupilNum; i++) {
     led.setPixelColor(pupilLED[LR][i], led.Color(0, 0, 66));
   }
   //eyelid
   for(int i=0; i < eyelidNum[eyelid]; i++) {
     led.setPixelColor(eyelidLED[i], 0);
   }
 } else if (eyelid == 8){
   led.clear();
 }
 led.show();
}
void setup() {
 Serial.begin(115200);
 led.begin();
 led.setBrightness(brightness); // Initial Brightness 40
 led.show(); // Initialize all pixels to 'off'
 color = led.Color(0, 177, 55); //pupil color
 delay(100);
 qtra.read(sensorValues);
 iniSensorValL = sensorValues[0];
 iniSensorValR = sensorValues[1];
 blink(eyelid, LR);
}
void loop() {
 //QTR - 1A sensor value
 qtra.read(sensorValues);
 sensorValL = sensorValues[0];
 sensorValR = sensorValues[1];
 double rasioL = (double)sensorValL / iniSensorValL;
 double rasioR = (double)sensorValR / iniSensorValR;
 Serial.print(rasioL);
 Serial.print("  ");
 Serial.println(rasioR);
 if(rasioL > 0.985 && rasioR < 0.985){ //right
   for(int i = LR; i < 12; i++){
     blink(0, i);
     delay(40);
     LR = i;
   }
 }else if(rasioL < 0.985 && rasioR > 0.985){ //left
   for(int i=LR; i>2; i--){
     blink(0, i);
     delay(40);
     LR = i;
   }
 }else if(lid == false && rasioL < 0.96 && rasioR < 0.96){ //Blinking close
   for(int i = 1; i < 9; i++){
     blink(i, LR);
     delay(40);
     lid = true;
   }
 }else if(lid == true && rasioL > 0.96 && rasioR > 0.96){ //Blinking open
   for(int i = 8; i > 0; i--){
     blink(i, LR);
     delay(40);
     lid = false;
   }
 }else if(lid == false && rasioL > 0.96 && rasioR > 0.96) {   //normal
   //cnt++;
   //eyelid = 0;
   if(LR <= 7){
     for(int i=LR; i<=7; i++){
       blink(0, i);
       delay(40);
       LR = i;
     }
   }else {
     for(int i=LR; i>=7; i--){
       blink(0, i);
       delay(40);
       LR = i;
     }
   }
   Serial.println("通常時");
 }
 //Initial value refresh
 if (cnt > 10){
   iniSensorValL = sensorValL;
   iniSensorValR = sensorValR;
   cnt = 0;
 }
}