Face Tracking Using Arduino
In this tutorial, I will be showing you how to
track faces using Arduino and Python and make the camera follow the face. This
may sound difficult but trust me it isn't, All you need is basic knowledge of
Arduino and Python.
So let's get started...
Step 1:
Things You Will Need
The requirements are minimum. Here I have
provided part list of everything you need:
Hardware Requirements:
·
Arduino UNO (You
can use other boards )
·
Web Cam ( Mini
Web Cam)
·
Servos x
2 (I'll be using micro servos but you can use Standard
Servos)
·
Breadboard (For
prototyping)
·
Servo Pan
Tilt Kit (You can build one if you want)
Software Requirements:
·
Python 2.7 (Should be
installed, Linux OS usually have it pre-installed)
·
OpenCV (You
can download it separately or install using 'pip install' Explained further)
After every thing is gathered we can move on
to the Installation Step...
Step 2:
Setting Up Python Environment
Installing Python:
So first we need Python 2.7 up and
running. To do this first download and Install python 2.7.14. To check if
it is installed correctly Goto : Windows Search >> Type
"IDLE" >> Hit Enter. A Python Shell should pop up.
OR
In search type 'CMD' and hit enter to open
Command Prompt. In CMD type >> python and hit enter, Python
interface should display.
If you see an error in CMD, Do not panic you
probably need to set environment variable. You can follow this tutorial Here to
set up Environment Variable.
Installing 'pyserial', 'OpenCV" and
"numpy" in Python:
To install these modules we will
use use pip install,
First open CMD and type the following codes:-
>pip install
serial
>pip install
opencv-python
>pip install
numpy
these commands will install the
necessary modules. Now we can move to the coding part...
Step 3:
Python Script
Before starting to write code
first thing to do is make a new folder as all of the code needs to be stored in
same folder. So create a new folder, name it anything you want. and download
the 'Haarcascade' from below and paste it in the folder.
Now open notepad and write the script given
below, Save it as 'face.py' in the same folder as haarcascade. (You can
download the code I have provided the file below) :
#import
all the required modules
import
numpy as np
import
serial
import
time
import
sys
import
cv2
#Setup
Communication path for arduino (In place of 'COM5' put the port to which your
arduino is connected)
arduino =
serial.Serial('COM5', 9600)
time.sleep(2)
print("Connected
to arduino...")
#importing
the Haarcascade for face detection
face_cascade
= cv2.CascadeClassifier('haarcascade_frontalface_default.xml')
#To
capture the video stream from webcam.
cap =
cv2.VideoCapture(0)
#Read the
captured image, convert it to Gray image and find faces
while 1:
ret, img = cap.read()
cv2.resizeWindow('img', 500,500)
cv2.line(img,(500,250),(0,250),(0,255,0),1)
cv2.line(img,(250,0),(250,500),(0,255,0),1)
cv2.circle(img, (250, 250), 5, (255, 255,
255), -1)
gray
= cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
faces = face_cascade.detectMultiScale(gray,
1.3)
#detect
the face and make a rectangle around it.
for (x,y,w,h) in faces:
cv2.rectangle(img,(x,y),(x+w,y+h),(0,255,0),5)
roi_gray = gray[y:y+h, x:x+w]
roi_color = img[y:y+h, x:x+w]
arr = {y:y+h, x:x+w}
print (arr)
print
('X :' +str(x))
print ('Y :'+str(y))
print ('x+w :' +str(x+w))
print ('y+h :' +str(y+h))
# Center
of roi (Rectangle)
xx = int(x+(x+h))/2
yy = int(y+(y+w))/2
print (xx)
print (yy)
center = (xx,yy)
# sending
data to arduino
print("Center of Rectangle is
:", center)
data = "X{0:d}Y{1:d}Z".format(xx,
yy)
print ("output = '" +data+ "'")
arduino.write(data)
#Display
the stream.
cv2.imshow('img',img)
#Hit
'Esc' to terminate execution
k = cv2.waitKey(30) & 0xff
if k == 27:
break
Once this is done, move on to
write the code for Arduino...
haarcascade_frontalface_default.xml, download from here
face.py, download from here
Step 4:
Arduino Code
After the python script is ready
we need arduino sketch to control the servo. Refer the code below, paste it in
Arduino IDE and save it as 'servo.ino' in the same folder as face.py and
haarcascade. upload the code and move on to the next step to make the
connections.
(Downloadable file given below.)
#include<servo.h>
Servo
servoVer; //Vertical Servo
Servo
servoHor; //Horizontal Servo
int x;
int y;
int
prevX;
int
prevY;
void setup()
{
Serial.begin(9600);
servoVer.attach(5); //Attach Vertical Servo
to Pin 5
servoHor.attach(6); //Attach Horizontal Servo
to Pin 6
servoVer.write(90);
servoHor.write(90);
}
void Pos()
{
if(prevX != x || prevY != y)
{
int servoX = map(x, 600, 0, 70, 179);
int servoY = map(y, 450, 0, 179, 95);
servoX = min(servoX, 179);
servoX = max(servoX, 70);
servoY = min(servoY, 179);
servoY = max(servoY, 95);
servoHor.write(servoX);
servoVer.write(servoY);
}
}
void loop()
{
if(Serial.available() > 0)
{
if(Serial.read() == 'X')
{
x = Serial.parseInt();
if(Serial.read() == 'Y')
{
y = Serial.parseInt();
Pos();
}
}
while(Serial.available() > 0)
{
Serial.read();
}
}
}
servo.ino, download from here
Step 5:
Pan-Tilt Mechanism :-
I have used a readily available
kit for the Pan-Tilt. If you want you can make one yourself using wood/Plastic
or even 3D print one.
The one I used is pretty cheap, and very easy
to assemble. Yet if you want instructions on how to do that, you can find
it here.
Step 6:
Making Connections
The Circuit is pretty simple. Just
attach two servos to arduino.
·
Vertical
to Pin 5
·
Horizontal
to Pin 6
·
Power
to +5V
·
Ground
to GND
Check the circuit diagram for reference.
Step 7:
Testing
·
After
everything is done last thing to do is test if it works. To test first make
sure that servos are properly connected to arduino and sketch is uploaded.
·
After
sketch is uploaded make sure to close the IDE so the port is free to connect to
python.
·
Now
open 'face.py' with Python IDLE and press 'F5' to run the code. It will take a
few seconds to connect to arduino and then you should be able to see a window
streaming the web cam. Now the code will detect your face and the servos will
track it track it.
·
The
servo should move as you move the object. Now just attach the camera to the
servos so it will move along with servos.
Hope you like it. and learn something new.
