Design And Construction Of A Heart Beat Monitor

ABSTRACT

This work is on design and construction of a heartbeat monitor. Heartbeat monitor is a very vital health parameter that is directly related to the soundness of the human cardiovascular system. This project describes a technique of measuring the heart beat through a fingertip. While the heart is beating, it is actually pumping blood throughout the body, and that makes the blood volume inside the finger artery to change too. This fluctuation of blood can be detected through an optical sensing mechanism placed around the fingertip. The signal can be amplified further for the system to count the rate of fluctuation, which is actually the heart rate.

The aim of this work is to design a device senses the heart rate from the finger tip using IR reflection method and displays it on a three digit seven segment display in beats per minute. The circuit has an accuracy of 4 beats per minute.

TABLE OF CONTENTS

 TITLE PAGE

APPROVAL PAGE

DEDICATION

ACKNOWELDGEMENT

ABSTRACT

TABLE OF CONTENTS

CHAPTER ONE

• INTRODUCTION
• BACKGROUND OF THE PROJECT
• OBJECTIVE OF THE PROJECT
• PURPOSE OF THE PROJECT
• PROBLEM DEFINITION
• SIGNIFICANCE OF THE PROJECT
• SCOPE OF THE PROJECT
• FEATURES OF HEARTBEAT SENSOR
• APPLICATIONS OF HEARTBEAT SENSOR
• METHODOLOGY
• PROJECT ORGANISATION

CHAPTER TWO

LITERATURE REVIEW

2.0      LITERATURE REVIEW

2.1      OVERVIEW OF THE HEARTBEAT

2.2     FACTORS INFLUENCING HEART RATE

2.3      FACTORS DECREASING HEART RATE

2.4     REVIEW OF RELATED STUDIES

CHAPTER THREE

3.0      DESIGN METHODOLOGY

3.1      WORKING OF A HEARTBEAT SENSOR

3.2      HEARTBEAT SENSOR CIRCUIT DIAGRAM

3.3       HEARTBEAT SENSOR PRINCIPLE

3.4      SYSTEM OPERATION

3.6       CIRCUIT DIAGRAM OF HEARTBEAT MONITOR

3.7     DESCRIPTION OF COMPONENTS USED

3.8     CIRCUIT OPERATION

CHAPTER FOUR

RESULT ANALYSIS

4.1   CONSTRUCTION PROCEDURE

4.2    CASING AND PACKAGING

4.3    ASSEMBLING OF SECTIONS

4.4    PACKAGING

4.5    MOUNTING PROCEDURE

4.6   TESTING

4.7    RESULT ANALYSIS

CHAPTER FIVE

5.0      CONCLUSIONS, RECOMMENDATION AND REFERENCES

• CONCLUSIONS
• RECOMMENDATION
• FUTURE WORKS

5.4     REFERENCES

CHAPTER ONE

• INTRODUCTION

Heartbeat is the major sign that are routinely measured by physicians after the arrival of a patient [1]. Heart rate refers to how many times a heart contracts and relaxes in a unit of time (usually per minute).

Heart rate varies for different age groups. For a human adult of age 18 or more years, a normal resting heart rate is around 72 beats per minute (bpm). A lower heart rate at rest implies more efficient heart function and better cardiovascular fitness. Babies have a much higher rate than adults around 120 bpm and older children have heart rate around 90 bpm. The heart rate increases gradually during exercise and returns to its normal value after exercise. The rate at which the pulse returns to its normal value is an indication of the fitness of a person. If the heart rate is lower than the normal heart rate, it is an indication of a condition known as bradycardia and if the heart rate is higher than the normal heart rate, it is an indication of a condition known as tachycardia [2].

A heart rate monitor (HRM) allows one to measure/display heart rate in real time or record the heart rate for later study. It is largely used to gather heart rate data while performing various types of physical exercise. Measuring electrical heart information is referred to as Electrocardiography (ECG or EKG).

This work describes the design of a heart beat monitor using microcontroller as the heart of the system.

1.1                                           BACKGROUND OF THE STUDY

Heart beat rate means the number of heartbeats per unit time, usually expressed as beats per minute (bpm). The human heart pounds to pump oxygen rich blood to the muscles and carry cell waste products away from the tissues. Heartbeat rate can vary according to the demand of the muscles to absorb oxygen and excrete carbon dioxide changes such as during exercise or sleep. It also varies significantly between individuals based on age, fitness and genetics. This means that the heart must beat faster to deliver more oxygen rich blood. During exercise routines, the heartbeat rate gives a strong indication of how effective the exercise is to the body.

The patient monitoring systems is one of the major improvements in the global health care program because of its advanced technology. A patient monitoring system measures the heartbeat by using embedded technology. This advancement in technology is highly needed because many sick patients at the hospitals die because of high fever and heart attacks. The trend of cardiovascular disease has shown that heart beat rate plays a key role in determining the possibility of a heart attack. Heart diseases such as heart attack, coronary heart disease, congestive heart failure, and congenital heart disease are the leading causes of death for men and women in many countries. Most of the time, the aged people of the society are more prone to heart disease problems than the younger ones. For people who live alone with no one to monitor their health condition, this device offers an opportunity to them for a constant monitoring of their health status, it is developed to monitor and alert the doctors about the heartbeat condition of a patient. It is developed to give patients a timely and proper heath care.

These days it is not easy for doctors and the nurses to remain close to a patients bed side to monitor their heath condition. In the past, a huge and fixed monitoring device was used (only in the hospitals) to know the health status of a patient when on a bed. These monitoring devices are only available in the hospitals and are constantly on Many the of patient them are not user friendly so it is important that the doctors and family members will have a handy device that can always monitor their patients when they are not around.

Another vital thing to monitor in a patient is the heartbeat rate. It is very important that the heartbeat is to be normal. That is 72 BPM. If there is any abnormality, then the patient is in distress. Heartbeat rate means the number of heartbeats per unit of time. The normal heartbeat rate of a resting person is about 70 bpm for adult males and 75 bpm for adult females. The average heartbeat per minute for 25-year old ranges between 140-170 beats per minute while for a 60-year old it is typically between 115-140 beats per minute. Normally it is difficult to keep track of the abnormalities in the heartbeat count of by manual means. Patients are not well versed with the manual treatments, which the doctors normally use for tracking the count of the heartbeat. Thus, there must be some kind of device which would help patients and their family member to keep track of their health by themselves. This sole reason is why this project presents a heartbeat monitor. The concept of developing an RF. based patient monitoring device is to have a simple home and hospital based pulse monitoring device for sick person’s that are in critical condition and needs to be constantly or periodically monitored by clinician or family.

1.3                                                  PROBLEM DEFINITION

The human health is one of the most important concerns in the world today. Anything/everything becomes meaningless when one becomes sick and dies due to improper Medicare. For health reasons, people, governments and several voluntary bodies spend a lot of money to ensure a better health condition for themselves and the entire populace. Scientists and Engineers are always at work to device a means of supporting/sustaining a sound health condition for all through the invention of numerous technologies both Electrical/Mechanical gadgets that are in use for health care delivery today. The heart is a very delicate organ in the human body (once it stops beating, nothing else matters). Thus, If early actions are taken (and on time) the heart condition can be managed effectively and many patients can be cured and saved. The problem of patients slumping and dying is associated with cardiovascular arrests and can be checkmated this sensitive and highly effective device (the patient heartbeat and temperature monitor). This device has an outstanding advantage that it is easy to handle and access. Heartbeat rate and body temperature monitors are part of the most vital tools needed in first aid kit for saving lives. Unlike the x-ray, the heartbeat and temperature monitor does not impose any hazard to the human health. There devices in the market which can provide raw measurement data of the patients to the doctors, but the patients may not be able to interpret the medical measurement into a meaningful diagnosis due to their limited medical background. On the other hand, if raw medical data is delivered to the doctor, time is wasted and may pose a problem, but in emergencies waste of time can never be tolerated. It is tough to share data over large area within a short period. Most of the products available in the market have this drawback of limitation in flexibility and portability. If the heat that is produced from metabolism cannot be checkmated on time, it will cause a turbulent body temperature, which could be worse than 40°C and lead to headache, vertigo, low blood pressure, high energy consumption, unconsciousness and crocking up of body temperature regulation function.

1.3                                                 AIMS AND OBJECTIVES

The main aim of this work is to design a monitoring device that allows one to measure/display heart rate in real time or record the heart rate for later study.

1.4                                              PURPOSE OF THE PROJECT

The purpose of this work is to help the doctors and family members to keep track of the heartbeat condition of their loved ones [as well as their body temperature] in the case of an abnormality in the health condition (for those with heartbeat defects and those that run excessive high temperature beyond normal). If any varied change takes place, it is notified.

1.5                                         SIGNIFICANCE OF THE PROJECT

There are various instruments available in the hospitals to keep track of the internal body changes, but many of them have limitations regarding to maintenance, cost, size of instruments, and mobility. This project is so significant because it is mobile, small in size, cost effective, very easy to use, highly efficient performance, portable and light in weight etc. to help both the patient and the concerned doctor to take an appropriate action.

It is beneficial in terms of cost. It saves time and is very helpful to patients who live alone. It offers a freedom of movement to patients. It has low power consumption.

1.6                                                 SCOPE OF THE PROJECT

It is designed to operate with an alkaline battery of a minimum of 9 volts to a maximum of 12v consumes 50mA. It uses a buffer, temperature sensor, AT89c51 Microcontroller and a led display with buzzer for the alert. The hardware and soft ware of the system is oriented towards the AT89c51 single chip microcontroller. Hence, reducing the size of the device.

1.7                                    FEATURES OF HEARTBEAT SENSOR

1. Indicates heartbeat by a LED
2. Provides a direct output digital signal for connecting to a microcontroller
3. Possesses compact Size
4. Works with a working Voltage of +5V DC

1.8                                                                                                                                                                         APPLICATIONS OF HEARTBEAT MONITOR

1. Works as a Digital Heart Rate monitor

• Works as a Patient Health Monitoring System
• Used as a Bio-Feedback control of robotic applications

1.9                                         METHODOLOGY

To achieve the aim and objectives of this work, the following are the steps involved:

1. Study of the previous work on the project so as to improve it efficiency.
2. Draw a block diagram.

• Test for continuity of components and devices,

1. programming of microcontroller
2. Design and calculation for the work was carried out.
3. Studying of various component used in circuit.

• Construct the whole circuit.
• Finally, the whole device was cased and final test was carried out.

1.10                                               DEFINITION OF TERMS

Atrial Fibrillation (AFib or AF) – A type of irregular heartbeat that occurs when the upper chambers of the heart beat very fast and unpredictably, producing an irregular heartbeat.

Autonomic Reflex Testing – A series of tests that monitor blood pressure, blood flow, heart rate, skin temperature, and sweating in response to stimuli to determine if the autonomic nervous system is functioning normally.

Bradycardia – A slower than normal heart rate of under 60 beats per minute.

Cardiologist – A doctor who specializes in diagnosing, treating, and preventing diseases in the heart and blood vessels.

Cryptogenic Stroke – A stroke of unknown cause.

Echocardiogram – A device that provides a “moving” picture of the heart, heart valves, and how the heart is pumping.

Electrocardiogram (ECG) – A test that records the heart’s electrical activity.

Electroencephalogram (EEG) – A test that records brain wave activity to help determine where seizures may occur.

Electrophysiologist – A cardiologist who specializes in diagnosing and treating abnormal heartbeats, including when the heart beats too fast, too slow, or in a way that pumps blood inefficiently.

Electrophysiology (EP) Study – A test that reproduces abnormal heart rhythms and extra heartbeats so the heart’s electrical impulses and responses to the heartbeats can be evaluated.

Heart Palpitations  – Sensations that feel like the heart is pounding, racing, fluttering, skipping, or adding a beat.

Hemodynamic Testing – A test that evaluates the blood flow and pressure when the heart muscle contracts and pumps blood throughout the body.

1.11                                    PROJECT REPORT ORGANIZATION

The organization of the project report is well detailed and vast in its coverage. It covers all the activities encountered during the research work. The first chapter is the introductory chapter, which covers the background, project objectives, scope of the project, constraints and block diagram overview of the states. Chapter two presents the literature review. Chapter three covers the system analysis and design including the design methodology in block diagram form, implementation, which shows the component layout, the wiring schedule, the wiring diagram and the complete schematic diagram. Chapter four covers the testing and integration of the project design. The system testing was first carried out in a laboratory. Chapter five is the Conclusion, which includes the summary of achievements, problems encountered during project design, recommendation and suggestion for further improvement.

CHAPTER TWO

2.0                                                    LITERATURE REVIEW

2.1                                         OVERVIEW OF THE HEARTBEAT

A heartbeat is a two-part pumping action that takes about a second. As blood collects in the upper chambers (the right and left atria), the heart’s natural pacemaker (the SA node) sends out an electrical signal that causes the atria to contract. This contraction pushes blood through the tricuspid and mitral valves into the resting lower chambers (the right and left ventricles). This part of the two-part pumping phase (the longer of the two) is called diastole.

The second part of the pumping phase begins when the ventricles are full of blood. The electrical signals from the SA node travel along a pathway of cells to the ventricles, causing them to contract. This is called systole. As the tricuspid and mitral valves shut tight to prevent a back flow of blood, the pulmonary and aortic valves are pushed open. While blood is pushed from the right ventricle into the lungs to pick up oxygen, oxygen-rich blood flows from the left ventricle to the heart and other parts of the body.