Higher Diploma in Biomedical Engineering

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HIGHER DIPLOMA IN BIOMEDICAL ENGINEERING
HND FINAL ENGINEERING PROJECT: INTERIM REPORT
S
Eman Hassan CL/HNDBME/07/25
Varsha Kalubowila CL/HNDBME/07/26
Naween Dissanayake CL/HNDBME/07/05
Adisha Gamage CL/HNDBME/07/18

Abstract:
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Table of Contents
Chapter 01: Introduction.......................................................................................................................4
1.1 Background of the project:..............................................................................................................4
1.2 Problem identification.....................................................................................................................5
1.3 Aim and Objective...........................................................................................................................5
1.3.1 Aim.......................................................................................................................................5
1.3.2 Objectives.............................................................................................................................5
1.4 Scope and Limitation.......................................................................................................................6
Chapter 02: Background Study.............................................................................................................7
2.0 Theory.............................................................................................................................................7
2.1 ECG Detection Algorithms.....................................................................................................7
2.2 ECG Signal Filters...................................................................................................................8
Chapter 03: Literature Review..............................................................................................................9
3.1 ECG Circuitry..................................................................................................................................9
3.1.1 ECG Amplifier.....................................................................................................................9
3.1.2 Instrumentation Amplifier..................................................................................................11
3.1.3 Electrode.............................................................................................................................11
3.1.4 Biosensors..........................................................................................................................11
3.1.5 Pulse Sensor SEN-11574....................................................................................................12
3.1.6 ECG Filtering Techniques..................................................................................................12
3.1.7 A/D Conversion..................................................................................................................12
3.1.8 Transmitter.........................................................................................................................12
3.2 Data Processing.............................................................................................................................12
3.2.1 Microcontrollers.................................................................................................................12
3.3 Output............................................................................................................................................12
3.3.1 LCD....................................................................................................................................12
3.4 Emergency Alarm System.............................................................................................................12
Chapter 04: Methodology....................................................................................................................13
4.1 Overview of the design..................................................................................................................13
4.2 ECG Circuitry................................................................................................................................14
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4.3 Device to embed Microcontroller..................................................................................................15
4.4 Microcontroller..............................................................................................................................15
4.5 Thermal Sensor..............................................................................................................................15
4.6 Pressure Sensor..............................................................................................................................15
4.7 Emergency Alarm System.............................................................................................................16
4.8 Further Discussion on the Reviewed Project................................................................................16
REFERENCES....................................................................................................................................17
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Chapter 01: INTRODUCTION
1.1 Background of the project:
An ECG is a recording of the electrical activity on the body surface generated by the heart
aaccording to National Health Service, United Kingdom in 2018, ECG measurement is an
information that is collected through electrodes placed at designated locations on the body. It is the
best way to measure and diagnose abnormal rhythms of the heart, particularly abnormal rhythms
caused by damage to the conductive tissue that carries electrical signals by electrolyte imbalances.
The aim of ECG detection algorithm is to detect the characteristic waveforms of ECG, such as QRS
wave group which represents depolarization and contractions left and right ventricles. This includes
exporting the digitized data of ECG and then using programming languages to detect the high peak
QRS wave group through a threshold.
The National Heart, Lung, and Blood Institute, Disease and Condition Index in 2003, states that
abnormal ECG waveforms are mostly obtained from patients above 55 years old. Therefore senior
citizens are vulnerable to heart attack. Senior citizens need to be monitored closely to identify and be
alerted regarding any sudden changes on the heart condition so that necessary actions could be
taken. Usually a caretaker or a family member is responsible for measuring and recording the
important parameters and comparing them to see if the heart condition worsens or not. This requires
the caretaker/family member to be present near the patient at most times and the elder citizen may
even find it difficult to have to take ECG and such hourly every day. This will definitely hinder their
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Electrical disease Circulatory disease Structural disease
Problems with the electrical
system that regulates the
steady heartbeats cause heart
rate to be too slow or too fast.
High blood pressure and
coronary artery disease can
cause a stroke or heart attack
Heat muscle disease and
congenital abnormalities are two
problems that can damage the
heart muscle or valves.

daily routine. Thus, an installable multi-healthcare system with Heart Attack Detection is specially
designed as detection unit and as the medium asking for medical help in case of an emergency.
1.2 Problem identification
A proportion (45.3%) of the elder citizens suffer from diabetes and high blood pressure which are
both risk factors for heart attack. Elderly have a need for an extensive health monitoring and
treatment. They need extraordinary care and geriatric treatments that are expensive (Satharasinghe,
A., 2016). Therefore, the provision of long term health care is a most serious issue. Hiring a
caretaker would be wise but expensive as she/he will need to be paid a fee every month including all
the other expenses for the machines to measure the patient’s heart conditions.
The patient would not be able to spend his/her day as they please because the readings have to be
taken at specific times which will hinder their regular routine. If a family member is responsible,
then they would not be able to go for work or might not be sufficiently experienced to handle an
emergency situation if it arises. Thus a simpler and easier way to monitor the patient without
hindering his/her regular routine is important.
1.3 Aim and Objective
1.3.1 Aim
The main aim of this project is to be able to continuously measure the patient’s vitals without
obstructing the patient’s regular routines and to make their life safer and easier. Also, making sure
that there is no abnormality in the heart rhythms and if so, giving a warning before the emergency
call that gives the patient a chance to avoid heart attack.
1.3.2 Objectives
General objectives
 To measure patient’s heart rhythms using a wireless biosensor on the wrist and to produce an
alarm in case of an emergency through a microcontroller based program installed in the
walking stick or wheelchair
 To produce a wireless emergency communication system through Bluetooth in critical
conditions
Specific objectives
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