ABSTRACT summed as follows: · The biometric system/device.

ABSTRACT – In the today’s
world, people seriously take note of security, how their belongings or private
information is ensured. As a result, security system is being rapidly developed
and several optimal systems are presented. Biometric security using personal
fingerprint has been known as one of the most popular protection for recent
years, due to the fact that every person’s fingerprint is unique. This paper
represents a demonstration of the biometric gate using the fingerprint sensor
and processing with the microcontroller on Arduino UNO board.

KEYWORDS – Biometric system, Fingerprint
sensor, Servo motor


are methods of recognizing a person using a characteristic, physiological or behavioral, as a
basis automatically. Physiological examples are fingerprints, face recognition, DNA, iris and retina recognition,, and odor/scent. Behavioral examples include typing rhythm, gait, and voice, standing or walking posture. Biometric data are different and distinctive from personal information. Biometric security is a technique mechanism used to recognize and grant access to a system or facility based on the automatic and immediate verification of a person’s bodily elements. Since biometric security analyzes an individual’s physical characteristics or
biological data, it is considered the most foolproof security mechanism used for identity inspection.

process and theoretical model of a biometric system is overally the same in
spite of which type of biometric you are using, which is briefly summed as

The biometric system/device.

The enrollment of live sample.

Template is built and stored.

Live sample is compared and verified.

Access is granted and logged.



   In general a
biometric system having a positive result proves that the person who is authenticating is the same
person enrolling in the first place. Fingerprint recognition systems operate on the
efficient algorithm of the fingerprint image analysis by the processing power
of the system. There are two main algorithm categories to identify
fingerprints, which involve using optical, silicon and ultrasound to capture
the image with adequate detail of the fingerprint:

Minutia matching
collates particular details within the fingerprint ridges. At enrollment, the
minutia points are found, together with their relative positions to each other
and their directions. At the matching stage, the fingerprint image is processed
to extract its minutia points, which are then compared with the registered

matching compares not only separate points but also the
general features of the fingerprints. Characteristics of the fingerprint may consist of areas of certain interest involving ridge thickness, density and
curvature. At
enrollment stage,
small segments and their relative distances are taken from the fingerprint. Areas of interest are
non-ideal ones like the area around a minutia point,
areas with uncommon combinations of ridges and areas
with low curvature radius.

   The two main
functions of a biometrics system are storing templates and comparing to verify. The storing
process varies from different systems: Some systems store a large amount of information
in great detail and will digitalize and compress the information. Once the fingerprint
template is kept in an accessible database, an individual’s fingerprint can be
compared whenever the system is gained access to. You are granted
access when both the stored and user’s fingerprint match. Fingerprint readers
use this unique aspect which derive from certain areas where fingerprint lines form,
merge or loop to generate a code.

Implemented system

   In this project,
we use the Fingerprint Sensor Module to save fingerprint as template. We use 4
push buttons: Enroll/Back, Delete/OK, Up/Match and Down/Match. Every button has
two functions. Enroll button is used for registering new template into the
system It also function as the Back button. When the used needs to save new template,
he/she has to press Enroll button. The LCD will ask for the location ID where he/she
wants to store the fingerprint template. At this moment, if the user don’t want
to continue further, he/she may press the Enroll button again to go back (the Enroll
button has back function now). Del/OK button has two functions as well. When
the user enrolls new fingerprint, he/she needs to select fingerprint’s location
ID by using Up/Match and Down/Match (they also have double functions). Then the
user has to press Del/OK button (this time it behaves as OK) to continue with
selected location ID. Up/Down buttons also support fingerprint match function.

Block diagram

are divided into hardware and software.

Fig. 1: Block
diagram of biometric gate using
fingerprint sensor


4.1    Fingerprint sensor module

   Fingerprint sensor module is a module which
captures fingerprint image and then converts it into the equivalent template
and saves them into its memory on selected ID (location) by Arduino. This
module can directly interface with any 3.3V or 5V microcontrollers with TTL
serial. We can also enroll
new fingerprint directly – up to 162 fingerprints can be stored in
the onboard FLASH memory. There’s a red LED in the lens that lights up during a
photo so we know it’s working.

Arduino UNO R3 SMD

   The Arduino Uno SMD is a version of the Arduino
Uno but uses an surface mount version of the Atmega328P instead
of the through-hole version. The board is based on the ATmega328.It has 14 digital input/output pins (of which 6 can be
used as PWM outputs), 6 analog inputs, a 16 MHz crystal
oscillator, a USB connection, a power jack, an ICSP header, and a reset button.
It contains everything needed to support the microcontroller; simply connect it
to a computer with a USB cable or power it with a AC-to-DC adapter or battery
to get started.

 ATmega328 microcontroller

   The Atmel 8-bit AVR RISC-based
microcontroller combines 32 kB ISP flash memory with read-while-write
capabilities, 1 kB EEPROM, 2 kB SRAM, 23 general purpose I/O lines, 32 general
purpose working registers, three flexible timer/counters with compare modes,
internal and external interrupts, serial programmable USART, a byte-oriented
2-wire serial interface, SPI serial port, 6-channel 10-bit A/D converter
(8-channels in TQFP and QFN/MLF packages), programmable watchdog timer with
internal oscillator, and five software selectable power saving modes. The
device operates between 1.8-5.5 volts. The device achieves throughput
approaching 1 MIPS per MHz

Servo motor

   The motor is attached to a plastic panel to act as a gate,
which will open only if the system verify the correct fingerprint.


   In this
project we use Arduino IDE with the Adafruit Fingerprint Sensor Library to control the fingerprint
module; the Liquid Crystal Library to control LCD displays and Servo Library to
control the Servo motor.


   In this
project, we use a gate that will only open when the fingerprint input is
already stored in the module. To begin, the user has to store his fingerprint template
by pushing the Enroll/Back button. The LCD will ask the user to select location
ID where the fingerprint will be stored by using Up/Down button . After choosing
location ID, the user has to press the Del/OK button. The LCD will now require
the user to put the finger into the fingerprint module. The user will place his
finger in the sensor twice. The fingerprint module will scan and capture the data
of the fingerprint and convert it into templates and store it into the
fingerprint module’s memory with the selected ID. By now the user can open the
gate by placing the same finger that he/she has enrolled into the system and
then press Match button (Up/Down button). Using the same process, the user can store
more fingerprint templates.

Figure 2: System flowchart

   If the user
wants to remove or delete any of the stored templates, he/she needs to press
Del button. Upon pressing Del button, the LCD will ask for the location ID to
be deleted. The user will select which ID and press OK (same Del button). The
LCD will notify that the fingerprint has been deleted successfully. Now the
user may check whether it has been deleted or not by placing the same finger
over the fingerprint module and pressing Match button (Up/Down button).

Fig. 3: Delete block


   When the
placed finger is valid the gate will open. After 5 seconds the gate will be
closed automatically. The user may modify gate opening and closing according to
how they need. Servo motor is in charge of the opening and closing of the gate.


Fig 4: Fingerprint verify block


1.      Result

   The hardware implementation of the circuit is shown
in Fig. 5 and the correct
fingerprint input is shown in Fig. 6

Fig. 5. Hardware implementation


Fig. 6. Gate opened with proper fingerprint


2.     Problem encounterd
and solution

   During of
the project, we came across some problems that were an obstacle to the proper
functioning of the system. There were hardware as well as software issues. Out
of many problems encountered, some of them are listed below.

Adjusting the
contrast of the LCD

connecting the LCD with the Arduino, the VEE pin is connected directly to GND
thus the background light is always at maximum. Therefore the LCD is too bright
to see and it consumes a lot of power.

Connect the VEE pin through a 10k ohm potentiometer to adjust the contrast of
the LCD>

Problem with
closing the gate

verifying the correct fingerprint, the gate will open but not close
automatically because there are no hinges between the motor and the gate.

   Solution: Design a hinge to
attach the blade of the motor with the gate.


   In the
Internet of Thing (IoT) era, system management over the Internet is the trend,
which creates a smarter system that can help people control wherever and
whenever with Internet connection. To execute the idea, we intend to combine
our system with a Wi-Fi chip ESP8266, which can transmit system’s data to a
server established by our computer. Our model is proposed as the following

Fig 7: Socket server model

   By this way, the host can
acquire the gate’s activity information such as signed in ID, timestamp and
also alert when someone tries to open the door without proper fingerprint.


   In this paper, a simple, user-friendly, biometric gate using fingerprint as authentication has been
introduced. Any unauthorized user will be unable to open the gate. The system
is more reliable and secured than conventional security systems used either
knowledge-based methods and token-based methods. It is also extendible and
further additions can be done.




   We would like to say thank to Prof. PhD ??ng
Thành Tín for all your time of supervising and supporting us all the time to
finish this project and all
friends who always give a hand when we need. This work is supported by the
Faculty of Electricals and Electronics Engineering, Ho Chi Minh University of
Technology, Vietnam National University, Vietnam.