Download pa college of engineering certificate

P.A. COLLEGE OF ENGINEERING
(Affiliated to Visvesvaraya Technological University & recognized by AICTE)
DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERING
CERTIFICATE
Certified that the project work entitled “HEALTH MONITORING SYSTEM” has been carried
out by Ms. A MAHALASA PAI, USN 4PA12EC001; Ms. DEEPIKA AJAYKUMAR, USN
4PA12EC020; Ms. GAYATHRI K M, 4PA12EC023; Ms. RABIYA SUHAIRA, USN
4PA12EC059, bonafide students of P.A. College of Engineering in partial fulfillment of the
requirements for the award of the degree of BACHELOR OF ENGINEERING in
ELECTRONICS & COMMUNICATION of Visvesvaraya technological University, Belgaum,
during the year 2015-2016. It is certified that all corrections/suggestions indicated for internal
assessment have been incorporated in the report deposited in the departmental library. The project
report has been approved as it satisfies the academic requirements in respect of project work
prescribed for the said degree.
Prof. Chandana B. R
Prof. Abdullah Gubbi
Project Guide
Head of the Department
Dr. Abdul Sharief
Principal
EXTERNAL VIVA
Name of the examiners
Signature with date
1.
________________________
_____________________________
2.
________________________
_____________________________
ACKNOWLEDGEMENTS
We would like to express our gratitude and appreciation to all those who gave us the necessary
support to complete this project.
We are thankful to the project guide, Mrs. Chandana B R, Assistant Professor, Dept. of
Electronics and Communication, for her guidance throughout our work.
We thank the HOD of Electronics and Communication Dept, Prof. Abdullah Gubbi, for his
support and guidance.
We are indebted to the principal Dr. Abdul Sharief, and the management of P.A College of
Engineering for providing an environment with all facilities that helped us in completing our
project.
We are extremely grateful to project coordinators, Dept. of Electronics and Communication for
their guidance and support throughout the project.
We are indebted to various technical societies, research institutes and scientists for their valuable
contribution towards science and technology based on which we were able to do this project.
We take this opportunity to thank all teaching and non-teaching staff of the Department of
Electronics and Communication Engineering for their help.
We thank the almighty for everything and also our parents for their support and encouragement
throughout this project.
ii
Health Monitoring System
Project Report 2016
ABSTRACT
Health monitoring system measures and monitor important physiological data of patient. It
accurately describes the status of his/her health and fitness. It consist of sensors, data acquisition
unit, Arduino and the software. The project describes a health monitoring system using
embedded devices. The system consists of three modules: first module that measures body fat
using principle of bio-impedance analysis which uses a small amount of alternating current to
flow between the electrodes, thus measuring the body impedance. The second module that
detects heart rate, by measuring the pulse count in the finger. Third one is for the measurement
of body temperature. Modules are serially interfaced to Arduino Uno along with analog to
digital conversion for temperature sensor and body fat analyzer.
Department of ECE, PACE
i
LIST OF FIGURES
Figure No.
Figure Name
Page No.
1.1
Measuring body fat using skin calliper
02
1.2
Hydrostatic weighing
03
1.3
Measuring body impedance
03
2.1
Five compartment model for human body
06
2.2
Heart beat sensor
08
2.3`
Temperature sensor
08
2.4
Block diagram of health monitoring system
09
3.1
Opto-isolator circuit: Isolate current source generated from MCU
10
3.2
Human impedance circuit: Get voltage across two electrodes
10
3.3
Split supply circuit: Split 9V battery into +4.5 V and -4.5V rails
11
3.4
Opto-isolator circuit with low pass filter
11
3.5
Electrodes
12
3.6
Digital heart beat sensor
13
3.7
Temperature sensor LM35
14
3.8
Internal circuit diagram of LM35
15
3.9
Regulated power supply
16
3.10
Arduino Uno
17
3.11
Arduino Uno architecture
18
3.12
ATmega328 IC
20
3.13
Pinout of Atmega328
21
3.14
LCD display
22
3.15
Pin diagram of LCD display
22
4.1
Flow chart for health monitoring system
23
4.2
Arduino program window
24
7.1
Health monitoring system
28
7.2
Output of body fat analyzer
28
7.3
Output of body fat analyzer on LCD display
29
7.4
Output of heart beat sensor
29
7.5
Output of temperature sensor
29
LIST OF TABLES
Table No
Table name
Page No.
2.1
Body fat chart for men and women based on their ages.
07
3.1
Technical Specification
18
CONTENTS
CHAPTER 1 ........................................................................... Error! Bookmark not defined.
INTRODUCTION.................................................................. Error! Bookmark not defined.
1.1 LITERATURE SURVEY ................................................................................................ 2
1.1.1 SKIN FOLD CALIPER METHOD .......................................................................... 2
1.1.2 HYDROSTATIC WEIGHING METHOD ............................................................... 3
1.1.3 BIOELECTRICAL IMPEDANCE ANALYSIS ...................................................... 3
CHAPTER 2 ............................................................................................................................. 4
PROPOSED METHOD........................................................................................................... 4
2.1 BODY FAT ANALYZER ............................................................................................... 4
2.1.1 BODY COMPOSITION ........................................................................................... 8
2.2 HEART BEAT SENSOR .............................................................................................. 10
2.3 TEMPERATURE SENSOR LM35 ............................................................................... 10
2.4 BLOCK DIAGRAM ...................................................................................................... 11
CHAPTER 3 ........................................................................................................................... 12
HARDWARE DISCRIPTION .............................................................................................. 12
3.1 BODY FAT ANALYZER CIRCUIT ............................................................................ 12
3.1.1 OPTO-ISOLATOR CIRCUIT: ISOLATE SIGNAL FROM MCU ....................... 12
3.1.2 GETTING VOLTAGE ACROSS TWO ELECTRODES ...................................... 12
3.1.3 SPLIT 9V BATTERY SUPPLY ............................................................................. 13
3.1.4 ISOLATING SIGNAL BACK TO MCU ............................................................... 13
3.2 ELECTRODES .............................................................................................................. 14
3.3 DIGITAL HEART BEAT SENSOR ............................................................................. 15
3.4 TEMPERATURE SENSOR LM35 ............................................................................... 16
3.4.1 INTERNAL CIRCUIT DIAGRAM OF LM35 ...................................................... 17
3.5 REGULATED POWER SUPPLY ................................................................................. 18
3.6 ARDUINO ..................................................................................................................... 19
3.6.1 TECHNICAL SPECIFICATION ........................................................................... 20
3.6.2 INPUT AND OUTPUT .......................................................................................... 21
3.7 ATmega328: .................................................................................................................. 20
3.8 LCD DISPLAY:............................................................................................................. 24
CHAPTER 4 ........................................................................................................................... 25
SOFTWARE DISCRIPTION ............................................................................................... 25
4.1 FLOW CHART .............................................................................................................. 25
4.2 ARDUINO ..................................................................................................................... 26
4.2.1 ADVANTAGES OF ARDUINO SOFTWARE ..................................................... 27
CHAPTER 5 ........................................................................................................................... 28
ADVANTAGES AND DISADVANTAGES ........................................................................ 28
5.1 ADVANTAGES ............................................................................................................ 28
5.2 DISADVANTAGES ...................................................................................................... 28
CHAPTER 6 ........................................................................................................................... 29
APPLICATIONS ................................................................................................................... 27
CHAPTER 7 ........................................................................... Error! Bookmark not defined.
EXPERIMENTAL RESULTS.............................................................................................. 30
7.1 HEALTH MONITORING SYSTEM ............................................................................ 30
7.1.1 BODY FAT ANALYZER ...................................................................................... 30
7.1.2 HEART BEAT SENSOR ....................................................................................... 30
7.1.3 TEMPERATURE SENSOR ................................................................................... 30
CHAPTER 8 ........................................................................................................................... 31
CONCLUSION AND FUTURE SCOPE ............................................................................. 30
CHAPTER 9 ........................................................................................................................... 31
REFERENCES ....................................................................................................................... 31
APPENDIX ............................................................................................................................. 32
CHAPTER 1
INTRODUCTION
Health is one of the global challenges for humanity. According to the constitutions of World
Health Organization (WHO) the highest attainable standard of health is a fundamental right
for an individual. Healthy individuals lead to secure their lifetime income and hence to
increase in gross domestic product. A modernized healthcare system should provide better
healthcare services to people at any time and patient friendly manner. Health monitoring
system, a major improvement in hospitality because of its advance technology. Health care
sensors are playing vital role in hospitality like temperature sensors, heartbeat sensors,
electrodes.
Bioelectrical impedance analysis is commonly used method for estimating body composition,
and in particular body fat. It determines the electrical impedance, or opposition to the flow of
an electric current through body tissues which can then be used to calculate an estimate
of total body water. Bioelectrical impedance analysis involves passing a small electrical
current through the body and measuring the resistance encountered. Impedance is greatest in
fat tissue, which contains only 10-20% water, while fat-free mass, which contains 70-75%
water, allows the signal to pass much more easily.
By using the impedance measurements along with a person's height and weight, and body
type (gender, age, fitness level), it is possible to calculate the percentage of body fat. Using
BIA to estimate person's body fat assumes that the body is within normal hydration ranges.
When a person is dehydrated, the amount of fat tissue can be overestimated. Factors that can
affect hydration include not drinking enough fluids, drinking too much caffeine or alcohol,
exercising or eating just before measuring, certain prescription drugs, illness, or a woman's
menstrual cycle. Measuring under consistent conditions will yield best results with this
method.
Heart beat sensor and temperature sensor are compact in size, it is used to monitor heart beat
in digital form and temperature.
1.1 LITERATURE SURVEY
It is always been easy to record one's weight loss. However, it is more tedious to measure
one's body fat percentage. There are different methods to measure body fat percentage like
skin calipers and hydrostatic underwater weighing which are not simple. However
bioelectrical impedance analysis provides a quick and easy method to estimate one's fat
content. The inspiration of this project is to promote personal health and to track workout
progress.
1.1.1 SKIN FOLD CALIPER METHOD
The skin fold method measures body fat percentage by pinching fat with fingers then
measuring the thickness with a body fat caliper. The reading is given in millimeters and
compared to a chart with age and gender to arrive at body fat percentage. The drawback of
this method is variability of measurements so less accurate, requires a skilled fitness
professionals.
Fig.1.1.1 Measuring body fat using skin caliper.
1.1.2 HYDROSTATIC WEIGHING METHOD
This method is considered the “Gold Standard” (+/- 1.5% error) of body fat measurement that
requires being submerged in a specialized tank of water because bone and muscle are more
dense than water, a person with a larger percentage of fat free mass will weigh more in the
water and have a lower percent body fat. Conversely, a large amount of fat mass will make
the body lighter in water and have a higher percent body fat. This method is very accurate but
drawback of this methods are impractical, expensive, not repeatable.
Fig.1.1.2 Hydrostatic Weighing
1.1.3 BIOELECTRICAL IMPEDANCE ANALYSIS
Bioelectric Impedance Analysis, determines the electrical impedance, or opposition to the
flow of an electric current through the body. Muscle has high water content, and is highly
conductive, while fat has lower water content and is not highly conductive. Based on the
strength of the impedance along with height and weight metrics, the BIA scale will estimate
fat-free body mass and body fat percentage.
Fig.1.1.3 Measuring body impedance
CHAPTER 2
PROPOSED METHOD
2.1 BODY FAT ANALYZER
Body fat analyzer using bioelectrical impedance technology uses a small alternating current
flowing between two electrodes held in hands to determine impedance. By determining the
opposition to the electric current through body tissues, it is possible to estimate the water
content of human body and used it to estimate fat free body mass. The current passes freely
through the fluids contained in muscle tissue, but encounters difficulty or resistance when it
passes through fat tissue. This resistance of the fat tissue to the current is termed bioelectrical
impedance.
A low level, imperceptible electrical current is sent through the body. The flow of the current
is affected by the amount of water in the body. The device measures how the signal is
impeded through different types of tissue. Tissues that contain large amounts of fluid and
electrolytes, such as blood, have high conductivity, but fat slow the signal down. As BIA
determines the resistance to flow of the current as it passes through the body, it provides
estimates of body water from which body fat is calculated using equations.
While measuring impedance through the cellular tissues it is assumed that resistor in parallel
with a resistor and capacitor in series. In this model the single resistor represents the
extracellular path and the resistor and capacitor in series represents the intracellular path.
In single tone body fat analyzer a frequency of 50kHz is used. Impedance measure vary with
the frequency of the AC current signal. By injecting 10µA of AC current through one's body
and measuring the voltage across the electrodes, it is possible to find the instantaneous
impedance.
In this project the two electrodes are made up of aluminium foil, it is considered as source
and sink(detector). The current generates voltages between different points in the body
volume according to Ohm’s law. The actual parameter measured with BIA is the voltage (V )
that is produced between two electrodes. The measurement normally is expressed as a ratio,
V/I, which is also called impedance (Z ). Based on the nature of the tissues, the impedance
varies with the frequency. The impedance value decreases as the frequency increases. The
relationship between frequency and impedance is nonlinear. [1]
Impedance is a function of two components: the resistance of the tissues and the additional
opposition(reactance) due to capacitance of membranes[2]. Impedance is given by:
Z=(Rˆ2 +Xcˆ2)ˆ1/2
BIA body fat analyzer is consider as safe because of several factors:

Currents at a frequency of 50 kHz are reported to be unlikely to stimulate electrically
excitable tissues, such as nerves or cardiac muscle.

Relatively small current magnitudes are involved, less than 1 mA, which are less than
the threshold of perception and in each stage isolation is provided.

The use of batteries or low-voltage power sources greatly diminishes risks from
macro shock.
CALCULATION
The amount of body fat percentage is calculated using the formula,
Males
= ( 0.0923 * weight ) + (0.1605 * age) – (0.0263 * voltage)
Females = (0.1871 * weight ) + (0.5800 * age ) – ( 0.0920 * voltage)
Commonly females has 10% more amount of fat than the males. The main intension of body
fat analyser is detection of amount of fat, then it is classified into different classes like lean,
normal, average and obese.
Here the nature of this measurement heavily depends on how hydrated the body is, there are
optimal conditions when using device:

The person should not drink alcohol within 48 hours of the measurement

The person should not engage in moderate or vigorous physical activity within 12
hours of measurement

The person should not eat or drink anything within 4 hours of measurement

The person should urinate within 30 minutes of measurement.
After calculation the fat range can be categorized into different classes:
FOR MEN
Classification
Fat Range
Athletes
6% - 13%
Fitness
14% - 17%
Acceptable
18% - 24%
Obese
25% and more
FOR WOMEN
Classification
Fat range
Essential Fat
10% - 13%
Athletes
14% - 20%
Fitness
21% - 24%
Acceptable
25% - 31%
Obese
32% and more
2.1.1 BODY COMPOSITION
The human body is composed of four main components: water, fat, protein and minerals.
Having a moderate amount of each component is important for a healthy life. The body
composition analysis is the clinical assessment of tissue and fluid distribution in the human
body. The body is modelled as a series of tissue and fluid compartments as shown in figure
2.1.1.
Fig.2.1.1 Five compartment model for human body
Fat Mass (FM) is the total amount of stored lipids in the body and consists of the following
types of fat: Subcutaneous fat is located directly beneath the skin. Subcutaneous Fat serves as
an energy reserve and as insulation against outside cold. Visceral fat is located deeper within
the body. Visceral fat serves as an energy reserve and as cushion between organs.
Fat-Free-Mass (FFM), also called as Lean Body Mass, is the total amount of non-fat (lean)
parts of the body. It consists of approximately 73% water, 20% protein, 6% mineral, and 1%
ash. Fat-free-mass is further divided into body cell mass and extracellular mass: Body Cell
Mass (BCM) contains all metabolically active tissues (living cells) of the body, including
muscle cells, organ cells, blood cells, and immune cells. BCM includes the “living” portion
of fat cells, but not the stored fat lipids. BCM also includes water inside living cells. This
water is called Intracellular Water (ICW). The main electrolyte of intracellular water is
potassium. Extracellular Mass (ECM) contains all the metabolically inactive (non-living)
parts of the body, such as bone minerals and blood plasma. ECM includes water contained
outside living cells. This water is called Extracellular water (ECW). The main electrolyte of
extracellular water is sodium. [3]
Table 2.1.1 Body fat chart for men and women based on their ages.
2.2 HEART BEAT SENSOR
Heart beat sensor with optical technique exploits the fact that tiny subcutaneous blood vessels
(capillaries) in any patch of skin (fingertip, ear lobe, etc.) furnished with a good blood supply,
alternately expand and contract in time with the heartbeat. An ordinary infrared
LED/phototransistor pair can sense this rhythmic change as small but detectable variations in
skin contrast. This method uses both transmittance and reflectance principles. It is a noninvasive method of finding heart rate i.e. no attachments or insertions on the body. It is
precise and cost effective.
Fig.2.2 Heart Beat Sensor
2.3 TEMPERATURE SENSOR LM35
LM35 is a temperature sensor that converts heat energy into electrical energy. Temperature
sensor senses the temperature and gives an output voltage corresponding to the sensed
temperature. In this it is used to monitor temperature of human body and also room
temperature.
Fig.2.3 Temperature sensor LM35
2.4 BLOCK DIAGRAM
Fig.2.4 Block diagram of health monitoring system
CHAPTER 3
HARDWARE DISCRIPTION
3.1 BODY FAT ANALYZER CIRCUIT
3.1.1 OPTO-ISOLATOR CIRCUIT: ISOLATE SIGNAL FROM MCU
Fig.3.1.1 Opto-isolator Circuit: Isolate current source generated from MCU
In order to isolate the user from the 230V line and the MCU power supply to guarantee user
safety, the circuit in fig. is used. The circuit uses an operational amplifier( LF353) at the
circuit input to drive the LED. The feedback photodiode sources current to R1 connected to
the inverting input of U1. This controls the behaviour of the photodiodes in the opto-coupler
to follow the input signal. By setting the two resistors (R1 and R2) equal to each other, we
obtain a unity gain so the output signal equals the input signal.
3.1.2 GETTING VOLTAGE ACROSS TWO ELECTRODES
Fig.3.1.2 Human Impedance Circuit: Get voltage across two electrodes.
The first stage of this circuit is the current source that takes in the isolated 50KHz signal and
generates 10µA current source at 50KHz frequency. The resistor from the negative terminal
to ground (R3) is in parallel with human impedance which forms a divider. This allows to
select R3 so that we get constant current across electrodes. The second stage of this circuit is
voltage subtractor which gives the voltage across the electrodes (represented by the resistor
labelled as human impedance). By making resistor R4=R5=R6=R7, the circuit behaves as a
unity gain differential amplifier so the output of this amplifier is simply the voltage difference
of the two electrodes.
3.1.3 SPLIT 9V BATTERY SUPPLY
Fig.3.1.3 Split Supply Circuit: Split 9V battery into +4.5 V and -4.5V rails.
In order to generate the +4.5 V and -4.5 V rails, the circuit in figure is used. The 9V battery
is essentially split into the two rails through the voltage divider ( the two 100KOhm resistors)
with output of the operational amplifier acting as virtual ground. The 1µF capacitor removes
noise in power rails. This way, these isolated rails can be used for the IL300 and the human
impedance circuit.
3.1.4 ISOLATING SIGNAL BACK TO MCU
Fig3.1.4 Opto-isolator Circuit with low pass filter: Isolates the signal back to MCU
The isolating circuit is same as the one used previously. Resistor R9 and R10 are equal to
each other to ensure unity gain since to obtain output is same as the input. Low pass filter is
used to smooth out signal so the microcontroller can perform calculations on the data from
the signal.
3.2 ELECTRODES
A solid electric conductor through which an electric current enters or leaves an electrolytic
cell or other medium. The basic metal plate electrode consists of a metallic conductor in
contact with the skin with a thin layer of an electrolyte gel between the metal and the skin to
establish the contact. Electrodes can also be made up of foil of metal (Aluminium), so as to
be flexible. Electrodes are placed on the body for bio-impedance measurement. Electrodes
are widely used to measure bioelectric signals. In this project current passed through the
electrodes is 10µA and signal of frequency 50kHz.
Bioelectrodes are a class of sensors that transduce ionic conduction to electronic conduction
so that the signal can be processed in electric circuits. The usual purpose of bioelectrodes is
to acquire medically significant bioelectrical signals. Human skin tends to have a very high
impedance compared with other voltage sources. For dry skin surface the impedance is more
than 20kOhm and for sweaty skin impedance varies from 0.5kOhm.
Fig.3.2 a) Aluminium foil electrodes b) Skin contact electrode
3.3 DIGITAL HEART BEAT SENSOR
The heart beat sensor is designed to provide digital output of heart beat when a finger is
placed on it. When the heart beat detector starts working, the top most LED will starts
flashing with every heart beat. The output of this sensor is connected to micro controller
directly to measure the heart beat per minute (BPM) rate. The sensor unit consists of an
infrared light-emitting-diode (IR LED) and a phototransistor, placed side by side, and the
finger is placed between sensor assembly. The IR LED transmits an infrared light into the
finger, a part of which is reflected back from the blood inside the finger arteries. The photo
diode senses the portion of the light that is reflected back. The intensity of reflected light
depends upon the blood volume inside the fingertip. So, every time the heart beats the
amount of reflected infrared light changes, which can be detected by the phototransistor.
Fig.3.3 Digital Heartbeat Sensor
FEATURES

Heart beat indication by LED

Instant output digital signal for directly connecting to micro controller

Total heartbeat count can be obtained serially every minute.

Compact Size.

Working Voltage +5V DC.
3.4 TEMPERATURE SENSOR LM35
The LM35 series are precision integrated-circuit temperature sensors, whose output voltage is
linearly proportional to the Celsius (Centigrade) temperature. The LM35 thus has an
advantage over linear temperature sensors calibrated in ° Kelvin, as the user is not required
to subtract a large constant voltage from its output to obtain convenient Centigrade scaling.
The LM35 has low output impedance, linear output, and precise inherent calibration make
interfacing to readout or control circuitry especially easy.
FEATURES

Calibrated directly in Celsius (Centigrade).

0.5 C accuracy guaranteeable (at +25 C).

Rated for full -55 to +150 C range.

Output is more accurate.

Suitable for remote applications.

Operates from 4 to 30 volts.

Low self-heating, 0.08 C in still air.
Fig.3.4 Temperature Sensor LM35
3.4.1 INTERNAL CIRCUIT DIAGRAM OF LM35
Fig.3.4.1 Internal circuit diagram of LM35
There are two transistors , one has ten times the emitter area of the other. This means it has
one tenth of the current density, since the same current is going through both transistors. This
causes a voltage across the resistor R1 that is proportional to the absolute temperature. The
amplifier at the top ensures that the voltage at the base of the left transistor (Q1) is
proportional to absolute temperature by comparing the output of the two transistors. The
amplifier at the right converts absolute temperature (measured in Kelvin) into Celsius. The
little circle with the 'i' in it is a constant current source circuit. The two resistors are calibrated
in the factory to produce a highly accurate temperature sensor.
3.5 REGULATED POWER SUPPLY
The regulated power supply accepts unregulated inputs from 9V to 15V AC or DC and gives
regulated output of 3.3V, 5V and 12V suitable for projects which needs precise voltage to
work. The input can come from step down transformer. Since board has Diode Bridge input
polarity does not matter. All outputs are brought to screw terminal. There is also an
unregulated output voltage to drive high current loads like relays and motors.
FEATURES

Input Voltage AC/DC 0-12.

Output Voltages +3.3V +5V, +12V.

Maximum Load 1 Amps.

LED Indicator.

All outputs to Screw Terminal.
APPLICATIONS

Mobile Phone power adaptors.

Regulated power supplies in appliances.

Various amplifiers and oscillators.
Fig.3.5 Regulated power supply
3.6 ARDUINO
Fig.3.6.1 Arduino Uno
The Arduino UNO is a microcontroller board based on the ATmega328. It has 14 digital
input/output pins (of which 6 can be used as PWM outputs), 6 analog inputs, a 16MHz
ceramic resonator, a USB connection, a power jack, an ICSP header and 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.
"Uno" means one in Italian and is named to mark the upcoming release of Arduino 1.0. The
Uno and version 1.0. will be the reference versions of Arduino, as moving forward.
Fig.3.6.2 Arduino Uno Architecture
3.6.1 TECHNICAL SPECIFICATION
Microcontroller
ATmega328
Operating Voltage
5V
Input Voltage
5V-12V
Digital I/O Pins
14[of which 6 provide PWM output]
Analog Input Pins
6
DC Current per I/O Pin
40mA
DC Current for 3.3V Pin
50mA
Flash Memory
32KB of which 0.5 KB used by Bootloader
SRAM
2KB
EEPROM
1KB
Clock Speed
16MHz
Table 3.6.1 Technical Specification
The Arduino Uno can be powered via the USB connection or with an external power supply.
The power source is selected automatically. External power can come either from an AC-toDC adapter or battery. The board can operate on an external supply of 6 to 20 Volts. If
supplied less than 7V and the 5V pin may supply less than five volts and the board may be
unstable. If using more than 12V, the voltage regulator may overheat and damage the board.
The recommended range is 7 to 12V.
The power pins are as the follows:

VIN: The input voltage to the Arduino board when it's using an external power
source.

5V: The regulated power supply used to power the microcontroller and other
components on the board. This can come either from VIN via an on-board regulator,
or be supplied by USB or another regulated 5V supply.

3.3V: A 3.3 volt supply generated by the on-board regulator. Maximum current draw
is 50mA.

GND :Ground pins.
3.6.2 INPUT AND OUTPUT
Each of the 14 digital pins on the Uno can be used as an input or output, using pinMode(),
digitalWrite(), and digitalRead () functions. They operate at 5V. Each pin can provide or
receive a maximum of 40 mA and has an internal pull-up resistor of 20-50kOhms. In
addition, some pins have specialized functions:

Serial: 0 (RX) and 1 (TX). Used to receive and transmit TTL SERIAL DATA. These
pins are connected to the corresponding pins of the ATmega8U2 USB-to-TTL serial
chip.

External Interrupts: 2 and 3.These pins can be configured to trigger an interrupt on a
value, arising or falling edge, or a change in value. See the attachInterrupt() function
for details.

PWM : 3, 5, 6, 9, 10 and 11. Provide 8-bit PWM output with the analogWrite()
function.

LED : 13. There is a built in LED connected to digital pin 13. When the pin is HIGH
value, the LED is on, when the pin is LOW, it's off.
3.7 ATmega328:
The Atmega328 is a very popular microcontroller chip produced by Atmel. It is an 8-bit
microcontroller that has 32K of flash memory, 1K of EEPROM, and 2K of internal SRAM.
The Atmega328 is one of the microcontroller chips that are used with the popular Arduino
boards. The Arduino Duemilanove board comes with either 1 of 2 microcontroller chips, the
Atmega168 or the Atmega328. Of these two, the Atmega328 is the upgraded, more advanced
chip. Unlike the Atmega168 which has 16K of flash program memory and 512 bytes of
internal SRAM, the Atmega328 has 32K of flash program memory and 2K of internal
SRAM. The Atmega328 has 28 pins. It has 14 digital I/O pins, of which 6 can be used as
PWM outputs and 6 analog input pins. These I/O pins account for 20 of the pins.
Fig.3.7.1 ATmega328 IC
20 of the pins function as I/O ports. It can function as an input to the circuit or as output.
Whether they are input or output is set in the software. 14 of the pins are digital pins, of
which 6 can function to give PWM output. 6 of the pins are for analog input/output. In
Atmega two of the pins are for the crystal oscillator. This is to provide a clock pulse for the
Atmega chip. A clock pulse is needed for synchronization so that communication can occur
in synchronous between the Atmega chip and to the device it is connected. The chip needs
power to the two of the pins, Vcc and GND, provide it power so that it can operate. The
Atmega328 is a low-power chip, so it only needs between 1.8-5.5V of power to operate.
Fig.3.7.2 Pinout of Atmega328
The Atmega328 chip has an analog-to-digital converter (ADC) inside it and without these
pins Atmega328 it wouldn't be capable of interpreting analog signals. The chip has 6 pins for
analog input. The ADC has 3 pins set aside for it to function- AVCC, AREF, and GND.
AVCC is the power supply, positive voltage, that for the ADC. The ADC needs its own
power supply in order to work. GND is the power supply ground. AREF is the reference
voltage that the ADC uses to convert an analog signal to its corresponding digital value.
Analog voltages higher than the reference voltage will be assigned to a digital value of 1,
while analog voltages below the reference voltage will be assigned the digital value of 0.
Since the ADC for the Atmega328 is a 10-bit ADC, meaning it produces a 10-bit digital
value, it converts an analog signal to its digital value, with the AREF value being a reference
for which digital values are high or low. Thus, a portrait of an analog signal is shown by the
digital value and it is its digital correspondent value. The last pin is the RESET pin. This
allows a program to be rerun and start over.
3.8 LCD DISPLAY:
LCD (Liquid Crystal Display) screen is an electronic display module and find a wide range of
applications. A 16x2 LCD display is very basic module and is very commonly used in
various devices and circuits. These modules are preferred over seven segments and other
multi segment . The LCDs are economical, easily programmable, have no limitation of
displaying special and even custom characters (unlike in seven segments).
Fig.3.8.1 LCD Display
A 16x2 LCD means it can display 16 characters per line and there are 2 such lines. In LCD
each character is displayed in 5x7 pixel matrix. This LCD has two registers, they are
command and data registers. The command register stores the command instructions given to
the LCD. A command is an instruction given to LCD to do a predefined task like initializing
it, clearing its screen, setting the cursor position, controlling display etc. The data register
stores the data to be displayed on the LCD. The data is the ASCII value of the character to be
displayed on the LCD.
Fig.3.8.2 Pin Diagram of LCD Display
CHAPTER 4
SOFTWARE DISCRIPTION
4.1 FLOW CHART
Fig.4.1 Flow chart for health monitoring system
4.2 ARDUINO
Arduino is an open-source platform used for building electronics projects. Arduino consists
of both a physical programmable circuit board (often referred to as a microcontroller) and a
piece of software, that runs on your computer, used to write and upload computer code to the
physical board. Arduino can be used to develop interactive objects, taking inputs from a
variety of switches or sensors, and controlling a variety of lights, motors and other physical
outputs. Arduino projects can be stand-alone, or they can communicate with software running
on computer.
The Arduino platform has become quite popular with people just starting out with electronics,
and for good reason. Unlike most previous programmable circuit boards, the Arduino does
not need a separate piece of hardware in order to load new code onto the board. To load the
program it just require USB cable. Additionally, the Arduino Integrated Development
environment uses a simplified version of C++, making it easier to learn to program. Arduino
is a key tool to learn new things.
Over the years Arduino has been the brain of thousands of projects, from everyday objects to
complex scientific instruments. A worldwide community of makers - students, hobbyists,
artists, programmers, and professionals - has gathered around this open-source platform, their
contributions have added up to an incredible amount of accessible knowledge that can be of
great help to novices and experts alike.
Fig.4.2 Arduino program window
4.2.1 ADVANTAGES OF ARDUINO SOFTWARE

Inexpensive - Arduino boards are relatively inexpensive compared to other
microcontroller platforms. The least expensive version of the Arduino module can be
assembled by hand, and even the pre-assembled Arduino modules less cost.

Cross-platform - The Arduino software runs on Winsows and Linux operating
systems. Most microcontroller systems are limited to Windows.

Simple, clear programming environment - The Arduino programming environment
is easy to use for beginners, yet flexible enough for advanced users to take advantage
of as well.

Open source and extensible software - The Arduino software is published as open
source tools, available for extension by experienced programmers. The language can
be expanded through C++ libraries, and people wanting to understand the technical
details can make the leap from Arduino to the AVR C programming language on
which it is based. It is possible to add AVR C code into Arduino programs

Open source and extensible hardware - Arduino is based on Atmel's ATmega8 and
ATmega168 microcontrollers. The plans for the modules are published under a
Creative Commons license, so experienced circuit designers can make their own
version of the module, extending it and improving it. Even relatively inexperienced
users can build the breadboard version of the module in order to understand Arduino
working and save money.
CHAPTER 5
ADVANTAGES AND DISADVANTAGES
5.1 ADVANTAGES
1. Bioelectrical impedance analysis is one of the quickest methods of testing body fat
.Testing itself takes less than a minute.
2. Bioelectrical Impedance Analysis method is accurate (4% margin of error).
3. To measure body fat it does not require skilled fitness professionals.
4. Repeated measures over time can be more accurate and thus more comparable to one
another.
5. Painless and easy method of analysis since electrodes are held in hands unlike
invasive electrodes.
6. Heart Beat sensor device can be considered as a very good alternative instead of a
stethoscope.
7. Temperature sensor (LM 35) is sensitive to a small change in temperature, which
gives accurate measurements.
5.2 DISADVANTAGES
1. The impedance measure is affected by body hydration status, body temperature, time
of day, and therefore requires well controlled conditions to get accurate and reliable
measurement. If a person is dehydrated, the amount of fat will likely be
overestimated.
2. People with pacemakers should not use bioelectrical impedance method for body
composition analysis.
CHAPTER 6
APPLICATIONS
1. Health monitoring system can be used in small clinics and hospitals for patients.
2. Health monitoring system can be used in old age homes.
3. An accurate heart rate monitor is a useful tool for ensuring a person is not
endangering himself by over-exercising. This is especially important for people with
recovering from heart conditions.
4 . Health monitoring system can comprehensively track activity level, body fat
percentage in one place. Using this information, it can help in maintaining a healthy
lifestyle. Hence it can be used in fitness centers.
5 . Health monitoring system helps in better nutrition, if one find that his/her body fat
percentage is increasing, and then he/she can make some changes in food habits.
CHAPTER 7
EXPERIMENTAL RESULTS
7.1 HEALTH MONITORING SYSTEM
The health monitoring system consist of three units. They are body fat analyser, heart beat
sensor and temperature sensor. Health monitoring system is tested for their real time
operation and functionally with different conditions to verify the performance of the project.
Image shows the overview of the health monitoring system.
Fig.8.1 Health Monitoring System
7.1.1 BODY FAT ANALYZER
A current of 10µA and frequency of 50kHz signal is passed through the human body, it
measures body impedance and calculates the body fat in percentage. From the obtained value
the body fat is categorised into different categories based on their age. The different
categories are lean, ideal, average and obese. To get body fat percentage press 'm' for males
and 'f' for females, and required data (age, weight) are entered.
7.1.2 HEART BEAT SENSOR
Heart beat sensor starts working when 'h' is pressed and finger is placed on it. Sensor
measures the heart beat per minute. Displays the value on LCD. The normal range of heart
beat is 60 to 100 per minute.
7.1.3 TEMPERATURE SENSOR
Temperature sensor starts working when 't' is pressed. Sensor measures temperature which is
accurate and displays value on LCD in ᵒC.
CHAPTER 8
CONCLUSION AND FUTURE SCOPE
8.1 CONCLUSION

The main goal of this study is to design a single frequency bioimpedance system for
clinical applications.

The body fat analyzer operated at a safe current that is ~10µA and frequency
generated is 50kHz and did not harm any test subjects.

The body fat analyzer provided body fat percentage with 4% of error margin.

The electrodes used are non-invasive.

Main intention of the project is to estimate body fat percentage and based on the value
obtained it is classified into lean, ideal, average, obese.

Health monitoring system also monitors heart beat rate and temperature along with
body fat analyzer.

Portable and easy to use.

Health monitoring system is user friendly.

The system provides a hardware and software integration solution for bioimpedance,
heart beat and temperature measurements which may be very useful and helpful in
clinical application.
8.2 FUTURE SCOPE
This project provides many opportunities for future extensions. One extension would be to
improve accuracy by implementing multi-frequency bio-impedance analysis. The current
with multi-frequency are able to pass through both inside and outside the cell, but the use
single low frequency is incapable of determining the water inside the cell [4].
In addition to the other changes, a separate GSM module can be serially interfaced to
Arduino, which would send SMS to the doctor when the body fat analysis is performed
remotely.
Additional body composition such as body mass index, blood pressure, blood glucose level
can be augmented to the existing module.
CHAPTER 9
REFERENCES
LITERATURE REFERENCES
[1]
Bioelectrical impedance analysis - Cornell University
[2]
A simple method of visceral fat accumulation by bioelectrical impedance analysisT. Shiga, Y. Oshima, H. Kanai.
[3]
Multi-frequency bioimpedance Monitoring Technique using network analyzer for body
composition- Mrs. Sharada Prakash Tondare, Dr.Shreeshail Tatyasaheb Patil.
IJERT ISSN:2278-0181
[4]
Bioelectrical impedance analysis in body composition measurement- National Institutes
of Health Technology Assessment Conference Statement.
WEBSITES
1. http://people.ece.cornell.edu/land/courses/ece476/FinalProjects/f2014/smb435_pkl25/
webpage
2. http://en.wikipedia.org/wiki/Bioelectical Impedance Analysis.
APPENDIX