Android Based Application for Blood Pressure and Real-Time Pulse Rate Monitor with SMS Alert Notification

Transcription

1 Android Based Application for Blood Pressure and Real-Time Pulse Rate Monitor with SMS Alert Notification by Patrick Wesley U. Chan Jett M. Nepomuceno Jonathan P. Ocampo A Design Report Submitted to the School of Electrical Engineering, Electronics Engineering, and Computer Engineering in Partial Fulfillment of the Requirements for the Degree Bachelor of Science in Computer Engineering Mapúa Institute of Technology December 2012

2 Approval Sheet Mapúa Institute of Technology School of EECE This is to certify that I have supervised the preparation of and read the design report prepared by Patrick Wesley U. Chan, Jett M. Nepomuceno, and Jonathan P. Ocampo entitled Android Based Application for Blood Pressure and Real-Time Pulse Rate Monitor with SMS Alert Notification and that the said paper has been submitted for final examination by the Oral Examination Committee. ii

3 ACKNOWLEDGEMENT First and foremost the researchers express their appreciation of the valuable assistance given by their adviser, Engr. Dionis A. Padilla, whose encouragement, guidance and support from the preliminary to the concluding level enabled us to accomplish the design project. We would like to acknowledge our instructor, Engr. Ayra G. Panganiban who was abundantly helpful and offered invaluable assistance, support and guidance, which inspired us to strive for the progress of the design. This project would not have been possible without the support of many people. The researchers wishes to express their gratitude for the assistance of everyone form the School of Languages, Humanities and Social Sciences (SLHS), especially to Prof. Kathleen Jean P. De Ungria, who patiently guided us in constructing paragraphs and checking the grammar of the document. We would like to thank our parents and siblings for supporting, providing financial means and encouraging us to finish the project. Lastly, we offer our regards and blessings to all of those who supported us in any respect during the completion of the project. iii

4 ROLES AND RESPONSIBILITIES OF GROUP MEMBERS Each member contributed on researching for the design project and development of prototype. The following shows the list of responsibilities of each member: Patrick Wesley U. Chan Circuit Design Documentation Hardware Design Software Design Jett M. Nepomuceno Circuit Design Documentation Hardware Design Software Design Jonathan P. Ocampo Circuit Design Documentation Hardware Design Software Design iv

5 TABLE OF CONTENTS TITLE PAGE APPROVAL SHEET ACKNOWLEDGEMENT ROLES AND RESPONSIBILITIES OF GROUP MEMBERS TABLE OF CONTENTS LIST OF TABLES LIST OF FIGURES ABSTRACT i ii iii iv v vii vii ix Chapter 1: DESIGN BACKGROUND AND INTRODUCTION 1 Customer 1 Need 2 Solution 2 Objectives of the Design 3 Constraints 3 Impact 4 Differentiation 5 Benefits 5 Definition of Terms 6 Chapter 2: REVIEW OF RELATED DESIGN LITERATURE AND STUDIES 10 A Mobile Monitoring System of Blood Pressure for Underserved in China by Information and Communication Technology Service 10 Current Pulse Oximeter Calibrators 12 Abnormal Heart Rate Detection Device Warning via Mobile Phone Network 12 Design of Wireless Mobile Monitoring of Blood Pressure for Underserved in China by Using Short Messaging Service 14 A&D UA-767PBT Blood Pressure Meter 14 v

6 Implementation of Cuff-less Continuous Blood Pressure Measurement System Based on Android 15 Portable Heart Rate Detector Based on Photoplethysmography with Android Programmable Devices 17 WSN Based Mobile u-healthcare System with ECG, Blood Pressure Measurement Function 19 Pulse Oximeter Signal Amplitudes in Different Body Parts for Wireless Solutions 21 Design of an Integrated Mobile System to Measure Blood Pressure 23 Chapter 3: DESIGN PROCEDURES 26 Hardware Development 30 Software Development 33 Prototype Development 40 Chapter 4: TESTING, PRESENTATION, AND INTERPRETATION OF DATA 45 Chapter 5: CONCLUSION AND RECOMMENDATION 51 BIBLIOGRAPHY 53 APPENDICES 55 APPENDIX A Operation Manual 55 APPENDIX B Pictures of Prototype 59 APPENDIX C Data Sheet 62 APPENDIX D Source Code 74 APPENDIX E Blood Pressure Chart 91 APPENDIX F Heart Rate Chart 92 vi

7 LIST OF TABLES Table 4.1: Standard Blood Pressure Level of Normal Patient 47 Table 4.2: Blood Pressure Test Table 47 Table 4.3: Heart rate Test Table 50 LIST OF FIGURES Figure 2.1: Block Diagram for Mobile Monitoring System of Blood Pressure 10 Figure 2.2: Polar T31 Transmitter 13 Figure 2.3: System Architecture for Cuff-less Continuous Blood Pressure Measurement System 16 Figure 2.4: Cuff-less BP measurement device 17 Figure 2.5: Figure 2.6 : Block Diagram for Portable Heart Rate Detector Based on Photoplethysmography 18 (a) Illustration of PPG sensor schematic; (b) physical case during signal extraction 19 Figure 2.7: Design Architecture of WSN Based Mobile u-healthcare System 21 Figure 3.1: Conceptual Framework 27 Figure 3.2: Design Data Gathering Procedure Flowchart 29 Figure 3.3: Figure 3.4: Block Diagram of Blood Pressure and Heart Rate Monitoring System 30 Blood Pressure and Heart Rate Monitoring System Schematic Diagram 31 Figure 3.5: Heart Rate Circuit Schematic Diagram 32 Figure 3.6: Heart Rate Sensor Schematic Diagram 32 Figure 3.7: Flow chart diagram of the system ;(a); (b); (c) 36 vii

8 Figure 3.8 : Case Model Diagram 39 Figure 3.9: PIC18F4520 (DIL40) Microcontroller 40 Figure 3.10: Watsons Digital Blood Pressure 40 Figure 3.11: Bluetooth Module 41 Figure 3.12: 7805 IC 41 Figure 3.13: LM324N IC 41 Figure 3.14: RT9163 IC 42 Figure 3.15: Blood Pressure and Real-Time Pulse Rate Monitor Circuit PCB layout 42 Figure 3.16: Heart rate PCB Layout 43 Figure 3.17: Bluetooth PCB Layout 43 viii

9 ABSTRACT Cardiovascular diseases are among the main causes of death around the world; these symptoms usually deal with the four critical vital signs of the human body. The researchers emphasize on the two of the four vital signs which deals with blood pressure and heart rate. The purpose of this study was to design a device that monitors blood pressure and heart rate with the use of PIC18F4520 Microcontroller which served as the main controller of the system. It has been mainly used to gather data from the heart rate and blood pressure circuit and sends the data to the Bluetooth module. The Bluetooth module was utilized to enable wireless communication between the monitoring systems and the Android smart phone. Another feature of the system is an automated notification system that alarms the patient s family and doctor through text messages when measurements from the blood pressure and heart rate monitor exceeds a certain limitation. This design is constructed for the purpose of helping medical patients that need heart rate and blood pressure monitoring, especially those who are always left at home. The idea of creating the device came from the need of our client for a remote monitoring system that also has an alarm system. Keywords: blood pressure and heart rate monitoring system, PIC18F4520, Android smartphone, Bluetooth technology ix

10 Chapter 1 DESIGN BACKGROUND AND INTRODUCTION The heart is one of the most important organs of the body. It consists of the atrium and ventricles. The two coordinates for the heart to pump blood throughout the body (Vikram Chandrasekaran, B.E.,2010). Diseases related to the heart or the cardiovascular system is one of the top causes of death in the world. More often than not, measurements of heart rate and blood pressure present doctors with an idea of the current status of the patient s cardiovascular system. These two vital signs are easy to acquire and produces quick results. Other factors like the protein level can also determine signs of a possible heart attack, although the process is quite complex and time consuming (M. Lucie Fritz; F. Philip Anderson, Ph.D.; Joseph P. Ornato, M.D.; James L. Tatum, M.D.; and Robert L. Jesse, M.D., Ph.D., 2001). The detection of abnormalities with the heart rate and the blood pressure is as important as notifying your doctor and your family about your current status. Immediate treatment is required once a sign for a possible heart attack is detected by the system. In this paper, a system is proposed that monitors blood pressure and heart rate, and at the same time offers an automated notification system when abnormal measurements have been detected by the system. The device is designed for home use, enabling remote monitoring of the patient. 1

11 Customer Dr. Charita M. Garcia is a Physician known for her experience in dealing with patients with heart diseases. With her clinic located at the 2 nd floor, Femar bldg., Manuel L. Quezon St., Antipolo City. Leonila Medoza is a Chemical Engineer who is diabetic and also has a high blood pressure; she frequently visits Dr. Charita M.Garcia for her scheduled checkups. Need Dr. Charita M. Garcia was having a hard time monitoring her patients having heart problems, especially those patients that require immediate treatment once abnormal signs like high blood pressure or high measurement of heart rate is experienced by the patient. She suggested a device that could monitor the heart rate and blood pressure of a patient and at the same time notify her when abnormalities have been detected in the measurements. In that way, she could immediately notify the patient or the patient s family what to do when such things occur. Solution The researchers provide a solution to the problem of the client, which is to design a portable monitoring device with the reference from the existing monitoring system. Features added to the design were specifically chosen to provide beneficiary help to the elderly. Safety precautions have been created based on the behavior of potential users. One of which is the addition of a heart rate monitor false alarm error checker. What this does is that it when a zero 2

12 reading from the heart rate monitor is produced, the system won t inform the relatives and the doctor immediately. A maximum of five readings will be taken, if the reading is still zero after five readings, then the device will contact the relatives and the doctor. Possibilities of them accidentally removing the oximeter might result to false alarms, hence the addition of the error checker. Objectives of the Design The main goal of the researchers is to create a device that could detect abnormalities with the heart rate or blood pressure and at the same time inform the patient s physician or doctor about their current condition so that immediate action can be done. The following are the specific objectives of the researchers to accomplish their main objective: First, to innovate an existing digital blood pressure device to enable it to display its output on an android phone via Bluetooth. Next is to create a heart rate system that also displays its output on an android phone via Bluetooth. Then, to create an android software that enables a user to view their heart rate and blood pressure, create their own record, and the capability to automatically text the patient s doctor and family to inform them when abnormalities with the heart rate or blood pressure has been detected by the system. Constraints Although the design is cheap and effective, it has certain limitations. First is that it is not as accurate as the procedures and tests done by doctors at hospitals. Next, the device only monitors the heart rate and blood pressure. For 3

13 the blood pressure, the user must have the proper posture like the conventional way of measuring it. The patient is required to be seated on a chair and ones body must be relaxed to minimize the alteration of pulse rate. For the software part, the device will only work on an android based operating system with the version of (Gingerbread) up to the latest version. Lastly, the system may require calibration of the potentiometer to provide efficient LED pulse rate reading for the benefit of patient. Impact Cardiovascular disease is one of the leading causes of death in the world, and also one of the most unpredictable. Cardiovascular disease is very complicated to detect and determine. There is no single method to determine the disease exactly, and a lot of tests and procedures should be done, which are expensive. Some patients who has critical cardiovascular disease needs to be admitted in the hospital for intensive monitoring, which also costs a lot of money. The researchers developed a device that could continually monitor a patient even without being admitted to the hospital, making their expenses cheaper. As for immediate treatment once some abnormalities has been detected by the device, the doctor and the family of the patient is immediately informed through a text message. The researchers want to develop a device that could be affordable and accessible to anyone, and to create an innovation in the medical field that could help to further develop the current technology in use. 4

14 Differentiation There were already a lot of designs that had the same function as ours, mainly to measure blood pressure and heart rate. Our design, however, implements the same system but with improved features. First is the use of Bluetooth technology. Bluetooth technology enabled our device to send output data (readings from the heart rate and blood pressure measurements) to the android phone wirelessly. It made the device less bulky and more convenient to view the output. Another is the use of an android phone for the display of the output. As of 2012, 56% of the total number of smartphones sold to end users has an Android operating system (Matt Hamblen, 2012). Based from this, we chose to develop a software for android since it is the leading operating system for smartphones. Benefits The significant benefit of this design is to improve the accessibility of the device for the patient, thus making the device handy anytime and anywhere. Innovating it with the smart phone became easier for the patient to communicate with the doctors/physicians, families and relatives. This in turn, also makes it easier for patients to be diagnosed with the proper guidance of the doctors/physicians even though the patient is not at the doctor s office. The device will automatically contact the family member or relatives through sending SMS details regarding the patient s status. Early diagnosis will decrease the patient s expenditure from consulting the doctor/physician. The two most important benefit of the device is to track the treatment; to keep track of their 5

15 condition and also give information to the patient and the doctor concern and to encourage control of the patient; gaining responsibility to their own health, motivating for improved diet, physical activities and proper medication use. Definition of Terms 1) Android - a mobile operating system based on the open Linux kernel was developed by Google. 2) Arrhythmia - a drastic change to the pattern of beating of the heart. It is also described as an irregular beating of the heart. The sudden change in heart beat could either be too fast or too slow. 3) Basic4Android - a programming language use for development environment for developers of Android application. 4) Blood Pressure - the pressure of the circulating blood against the walls of the blood vessels; results from the systole of the left ventricle of the heart; sometimes measured for a quick evaluation of a person s health (The Sage English Dictionary and Thesaurus, 2010). 5) Bluetooth Technology - a wireless LAN technology designed to connect devices of different functions such as telephones and notebooks in a small area such as a room (Forouzan, 2006). 6) C programming language - a high-level programming language that can be used for a variety of applications, from business programs to engineering created by Dennis Ritchie. 6

16 7) Calibration - the process of comparing an instrument's measuring accuracy to a known standard. 8) Cardiovascular disease - a type of disease that concerns the heart and blood vessels. 9) Database - a collection/group of data that are related with one another (Robert J. Robbins,1995 ). 10) Diastolic Pressure- the minimum pressure in an artery, which occurs when the heart contracts in between heartbeats. 11) Electrocardiogram (ECG) - a graphical recording of the cardiac cycle produced by an electrocardiograph (The Sage English Dictionary and Thesaurus). 12) Hardware - the physical components of a computer system, such as the processor, keyboard and monitor (Hardware and Computer Organization, Arnold Berger). 13) Heart rate - the rate at which the heart beats; usually measured to obtain a quick evaluation of a person s health (The Sage English Dictionary and Thesaurus). 14) Holter monitor a portable device for continuously monitoring various electrical activity of the cardiovascular system for at least 24 hours. It is commonly used for monitoring heart activity. 7

17 15) JAVA - a general-purpose programming language created by James Gosling and others at Sun Microsystems (The Sage English Dictionary and Thesaurus). 16) Microcontroller (MCU) - a microprocessor on a single integrated circuit that controls some or all of the functions of an electronic device (as a home appliance) or system (Webster Dictionary). 17) Oscillometric - a type of noninvasive blood pressure measurement which employs an occluding cuff. 18) Oximeter - a measuring instrument that measures the oxygen in arterial blood (The Sage English Dictionary and Thesaurus). 19) Printed Circuit Board (PCB) - a board made from an insulating, nonconductive material that has conductive metal tracks (electronic interconnects) called traces. Integrated circuits and components are soldered to the board, and metal traces between terminals connect the various devices and components. Multilayer circuit boards consist of multiple laminated layers of electrically integrated substrate, each with unique circuit traces (Donelly,2000). 20) Potentiometer - a resistor with three terminals, the third being an adjustable center terminal; used to adjust voltages in radios and TV sets (The Sage English Dictionary and Thesaurus). 8

18 21) Real-Time - relating to computer systems that update information at the same rate they receive information (The Sage English Dictionary and Thesaurus). 22) Sensor - any device that receives a signal or stimulus (as heat or pressure or light or motion etc.) and responds to it in a distinctive manner (The Sage English Dictionary and Thesaurus). 23) Software - describes a collection of computer programs, procedures and documentation that perform some tasks on an operating system (The Economic Properties of Software, Sebastian Engelhardt). 24) Sphygmomanometer - a device used for measuring the blood pressure. It contains an inflatable cuff that is wrapped around the arm, and mercury or a mechanical manometer to measure the pressure. 25) System - a set of interacting or interdepend entities, real or abstract, forming an integrated whole (An Introduction to Cybernetics, Chapman and Hall). 26) Systolic Pressure - the maximum pressure in an artery, which occurs when heart contracts; when it is beating, and blood is being pumped through. 27) Photoplethysmography - a device used to optically obtain a volumetric measurement of organs, which can be found in pulse oximeter. 28) PIC - a family of Harvard architecture microcontroller made by the Microchip Technology, derived from the PIC1640 originallly developed by 9

19 General Instruments Microelectronics Division. The name PIC initially referred to Programmable Interface Controller, but shortly thereafter was renamed Programmable Intelligent Computer (Encarta Encylopedia). 29) Pulse - Is the rhythmic contraction and expansion of the arteries with each beat of the heart (The Sage English Dictionary and Thesaurus). 30) Wireless - Using radio signals: using radio signals rather than wires (Encarta World English Dictionary). Chapter 2 REVIEW OF RELATED DESIGN LITERATURES AND STUDIES A Mobile Monitoring System of Blood Pressure for Underserved in China by Information and Communication Technology Service Figure 2.1: Block Diagram for Mobile Monitoring System of Blood Pressure 10

20 A research done by Jiang, Yan, Shi, Kandachar and Freudenthal (2010), includes wearable measurement devices and information receiver terminals. Patients are able to measure BP values independently, by wearable wrist devices. The data will be automatically transferred to a data server in CHC/point (P) real time. It will be then analyzed by the server and, where necessary, a short messaging service (SMS) alarm will be sent to the user s mobile phone. Finally, the data will be stored in the server for manual analysis by the caregiver. At the same time, the server can be connected to specialists in large hospitals through existing Internets and specialists (physicians with MD degree and more than five years clinic experience) will give advice if needed. By using this system, BP measurements are automatically delivered to the server at certain times throughout the day, depending on the patient s situation. Doctors in CHCs (Community Health Centers) can observe data from the server and analyze results (such as BP trend analysis) for every patient through dedicated (to be developed) software. If any medical problem occurs, e.g., when the BP level rises to problematic levels, feedback will be sent to both user terminals (patients) and database server. The difference of this product with existing wrist BP measurement devices in the market such as Omron, is the acceleration-detection module, which helps to decide the users body status automatically. In daily use, physical activity is the general reason for errors during BP measurement. An acceleration-detection module was designed, which can assess current bodily activity. The decision of 11

21 this module can advise patients whether current status is suitable for BP measurement. Current Pulse Oximeter Calibrators According to Reid, Robertson and Sonntag (2011), a pulse oximeter calibrator must fulfill certain criteria. According to Hornberger et al, it is important that the R-ratio signals that the pulse oximeter receives are within the calibration range of the device. The pulse oximeter must identify the device as a patient. It must also be able to assess the accuracy and correctness of data compared to an accepted standard. Finally, it must provide an absorbance that would be the same as a finger with known arterial blood saturation. To be detected as a patient, the calibrator would have to have a nonchanging absorbing component that absorbs proportional to the tissue and venous blood of a patient a pulsatile absorbing component that absorbs proportional to pulsating arterial blood. Current pulse oximeter calibrators do not meet the need of the commercial market. There are many designs, ideas, and patents of pulse oximeter calibrators and simulators/testers and use various methods to function. Most of them fall into one of three categories: mock circulatory, finger models, and electronic simulators. Abnormal Heart Rate Detection Device Warning via Mobile Phone Network A reseach done by Adisorn Sirikham(2010), created a device designed to send rate of heartbeat and warning signal via mobile phone network when 12

22 abnormal heart rate is detected. The hardware system consists of 3 main parts. The first is heartbeat signal receiving part which detects cardiac electrical signal on the skin. The second part is processing unit part that computes heart rate by using the data from the first part. And the last part is warning sender part that sends heart rate and warning signal to patient s physician or relative when the system found that the heart rate is abnormal. The one that will detect cardiac electrical signal on the skin is the Polar T31 Coded Transmitter is shown in figure 2.2. It is an electrocardiogram (ECG) chest belt. It detects the electrical impulses generated by the heart, and wirelessly transmits them to the heartbeat receiver. Figure 2.2: Polar T31 Transmitter Part To calculate heart rate, the electric heart beat pulse is received from the Polar receiver. The algorithm calculates the number of heart beat pulse multiplied by 60 and divided by the time, as in (1). HR = (n 60) / t (1) HR represents heart rate in beats per minute n represents number of heart beat pulse t represents time 13

23 Design of Wireless Mobile Monitoring of Blood Pressure for Underserved in China by Using Short Messaging Service A research done by Jiang, Zhuangzhi, Jun, and Prabhu, aims to provide an affordable medical service for community residents by designing an interactive medical monitoring system. This system consists of three units: 1) Smart sensor unit, which is wearable on patient s arm in order to register the required BP and transfer it by SMS module. 2)The server unit, which enables medical staff in the CHC/P to remotely observe patient s BP condition through a computer within an existing network. At the same time, the server unit can be connected to the big hospitals through existing internet, and the specialists in big hospitals will give some advises if needed. 3) The terminal unit, which allows Patient/User to access and query the medical bio-data recorded in the server as well as for the information notification (such as alarming function). BP measurement methodology is based on Oscillometric method. In this design, the terminal unit can be a mobile phone, a Personal Digital Assistant (PDA) or a computer with an SMS receiver. The server will not send a message unless the BP value is abnormal, so it will not affect user s normal life. A&D UA-767PBT Blood Pressure Meter Sultan and Mohan (2009) designed this meter to act as a Bluetooth master in the transfer of readings from the device to the mobile phone. The device has one large button to interface with users. When the button is pressed, the readings are taken and then displayed on its monitor. After displaying the 14

24 reading to the user the device transmits the readings to the mobile phone via Bluetooth. Implementation of Cuff-less Continuous Blood Pressure Measurement System Based on Android A research done by Xu, Guo, Yang, Yin, Zhang and Meng (2012), implements a noninvasive mobile system for monitoring blood pressure and to facilitate the continuous blood pressure monitoring of patients during daily life. Fig. 2.3 shows the structure of the designed system. In the system, the C8051f410 chip is used as MCU (Micro Controller Unit) of node modules to process signals and transmit related data. After establishing the connection of smart-phone with nodes, the MCU will send the sampled physiological signals to serial port and the HC-06 module, which is a Bluetooth transmission module, will transmit the data to an Android smart-phone automatically. Afterwards, the Android smart-phone can call up the related Bluetooth API (Application Programming Interface) functions to obtain corresponding data input and output stream so that they can complete the operation of receiving and sending the ECG (Electrocardiograph) and PPG (Photoplethysmograph) signals, then PTT (Partial Thromboplastin Time). Finally, the system can realize the real-time blood pressure monitoring. In the system, ECG signal is measured by the standard lead II configuration. ECG sensors are attached to user s two arms and right leg to acquire signals. Because ECG signal is weak and band limited at the range of

25 Hz ~ 100 Hz, the pre-processing part, which includes amplification and filtration, is significant to the acquisition module. The ECG signal, in order to attenuate noise, is passed through a bandpass filter composed of cascaded high-pass and low-pass integer filters. Then, smooth ECG signal is obtained by MCU. For PPG signals, the researchers acquire fingertip PPG with FP-100 Pulse Sensor which is a kind of piezoelectric pulse sensor. By a 45 Hz low-pass filter, the system removes 50 Hz power frequency interference, at the same time it can inhibit other high frequency noise. After amplification and filtration, ECG and pulse wave signals are sampled respectively by a 12-bits ADC (Analog to Digital Converter) port from the MCU. Figure 2.3: System Architecture for Cuff-less Continuous Blood Pressure Measurement System 16

26 Figure 2.4: Cuff-less BP measurement device Portable Heart Rate Detector Based on Photoplethysmography with Android Programmable Devices A research done by Che, Lao, Pun, Mak, Wan, and Vai (2012), used a sensor to detect the PPG from the patient s fingertip. Then, a simple conditioning circuitry was designed to prepare the signal for the ADC embedded in the microcontroller. Within the microprocessor, the digitized PPG signal was packeted and passed to the server computer via a pair of RF transceiver. Within the server computer, the PPG data was processed and stored for the sake of better diagnosis and treatment/record in the future. In the meanwhile, related information was sent to a smartphone for user s concern via Bluetooth. 17

27 Figure 2.5: Block Diagram for Portable Heart Rate Detector Based on Photoplethysmography The photoplethysmography is preferred in this design because measurement can be performed on fingertip without precise positioning. Additionally, the design can easily upgrade to blood oxygen saturation measurement. Every time when blood pumps to periphery (ejection phase), blood vessels expand due to the blood pressure from the heart, a pulse will be generated. And every time when the blood flows back (diastolic filling phase), another pulse follows. So the PPG signal will be the superposition of the pumping pulse and the reflected wave. Fig. 2.6 depicts the conceptual diagram of PPG measurement on fingertip. An infra-red LED and a detector were placed beneath the fingertip of the patient for measuring the change of blood volume by the activities of the heart. The volume change of the blood within the artery will directly affect the scattering light received by the photo-detector. 18

28 (a) (b) Fig. 2.6 (a): Illustration of PPG sensor schematic; (b) physical case during signal extraction WSN Based Mobile u-healthcare System with ECG, Blood Pressure Measurement Function A research done by Chung, Lee and Toh(2008), conceptualized placing an unobtrusive wireless sensor on a person s body to form a wireless network that provides the interoperability layers to access the patient s physiological signs by base station, and route to the monitoring PC in medical center. They have developed the medical devices integrated with ECG and blood pressure sensors accordingly in the system. 19

29 Figure 2.7: Design Architecture of WSN Based Mobile u-healthcare System In Fig. 2.7, shows the system hierarchy of a WSN based Mobile u-healthcare system comprising of sensing, communication and management layer. The core of sensing layer includes sensor and wearable devices such as chest belt and wrist band blood pressure monitor device which are integrated with ECG signal and blood pressure sensors parameters which can aggregate and transmit the collected vital signs to monitoring program beyond hospital or to wireless dongle and then relayed to hospital through mobile phone. The communication layer performs bi-directional data or command exchange via IEEE network and code division multiple access (CDMA) to connect between the sensor layer and management layer. The management layer includes a web server to handle the received data and respond upon the request to and from the cellular phone. A monitoring program in the server is used to monitor and analyze the vital signs 20

30 of a patient continuously. Only the suspicious abnormal vital signs will be transmitted to hospital server for further doctor s evaluation. Communication layer in the system architecture is designed to capture, record and as a distinctive feature to locally analyze ECG signals in a cell phone. The ECG Diagnosis Module has two sub-modules which are QRS (Q-wave R-wave S-wave) Detection Module and Decision Rule Module that are based on a set of if-then rules. The QRS Detection Module is based on Pan Tompkins QRS detection algorithm which consists of digital bandpass filter, differentiation, squaring and moving window integration. They believe that only one ECG parameter cannot provide adequate information for the doctor to make correct evaluation on patient. Therefore, blood pressure measurement is necessary since it is the most commonly measured physiological parameter often taken by doctor in order to assess the most basic body functions. Pulse Oximeter Signal Amplitudes in Different Body Parts for Wireless Solutions A research done by Antti Konttila, Miia Määttälä and Esko Alasaarela (2003), designed the pulse oximeter to be as adjustable as possible. To reach this goal receiver and transmitter modules were controlled programmatically by computer. Separate receiver and transmitter modules were built to enable versatile measurement geometries. Pulse oximeter system consists of PC, 21

31 LabVIEW 8.2 program, National Instruments USB-6211 data acquisition card, voltage source, transmitter module and receiver module. In the measurements, the researchers concentrated on studying signal-tonoise ratios (SNR) and normalized signal amplitudes instead of finding out actual SaO2 readings. That was done in search of an optimum spot that would provide strong noiseless signal from which actual SaO2 reading could later be calculated in our wireless sensor belt or wrist band development. All measurements that they have done use a special pulse oximeter device which was built in the University of Oulu. The device was built so that the angle between the transmitter and receiver can be changed based from the location of the sensor on patient s skin. By using this adjustable probe, it was possible to obtain visible pulse oximeter signal from almost every spot on patient s skin by adjusting the angle and simultaneously checking the signal on the computer screen. Each patient requires a different angle for measuring these spots, requiring the angle to be specified separately every time. Measurement spots were chosen so that a belt, a band or a clip could be used to secure the probe to the measurement spot. Every measurement was analyzed for five pulses generated by heartbeat. Those five pulses were averaged to represent that particular measurement. If five pulses could not be undoubtedly recognized by human judgment, then that particular measurement was declared as non-pulse measurement and parameters were set to zero. 22

32 Design of an Integrated Mobile System to Measure Blood Pressure A research done by Ashraf Tahat, Anwar Sacca and Yazeed Kheetan (2011) deploys the oscillometric BP measurement method on their device. This method of measuring BP is very often used for the measurement of the BP because of its excellent reliability. The oscillometric method is based on observing the magnitude of oscillations caused by the blood as it begins to flow into the arm, again, after it had been occluded during the maximum inflation of the cuff. When the pressure decreases in the cuff, pulsations will begin to be emitted by the artery; the pressure then reported on the device defines the maximal BP or Systolic blood pressure (SBP). When the pressure decreases in the cuff, the oscillations will become increasingly significant, until maximum amplitude of these oscillations defines the average BP or mean arterial pressure (MAP). Then, the oscillations can still be observed while the pressure is decreasing in the cuff, until they disappear; the pressure then read on the device defines the minimal BP or Diastolic blood pressure (DBP). In the design, the BP monitoring device measures the blood pressure using a microcontroller (PIC16F877A), a pressure sensor MPX5050GP, and a Bluetooth module (LinkMatik 2.0). The microcontroller controls a valve and an air pump. These were integrated on custom-made printed circuit board (PCB). When a measure command is received via Bluetooth from the mobile phone interface, the microcontroller will close the valve and trigger the air pump to inflate the cuff to a certain predefined high pressure value (180 mmhg). Then the cuff will start 23

33 to deflate slowly through the bleeding valve. The microcontroller will also acquire the sensor s measurement through its analog to digital converter (A/D) module. It will also calculate the BP and heart-rate based on these measurements. When readings are ready, the microcontroller will open the valve; send the acquired readings through its UART (Universal Asynchronous Receiver Transmitter) to the Bluetooth module, and in-turn to the controlling mobile phone. The main objective is to develop a mobile application that is capable of communicating with the BP monitoring device remotely over Bluetooth technology. The researchers wanted to achieve two main ideas in our application: to build a mobile application that has the ability to remotely start the BP measurement operation on the device, and to be able to receive data from the BP monitor device, to process and to display it in a convenient manner on the screen. Once the program is running and a proper connection has been established, the user will be capable of measuring the BP and heart-rate using the BP monitor device. This would be accomplished by selecting the Measure Blood Pressure button. The user will not be able to use any function on the main application unless the measurement process has ended. This is a form that shows that the BP measuring process is in progress. It will show up once the measurement process is started. It contains a picture box that contains an image of a dummy ECG signal, and the picture box is animated to allow it to move from left to right, from one edge of the form to the other. 24

34 They believe that only one ECG parameter cannot provide adequate information for a doctor to make the correct evaluation on patient. Therefore, blood pressure measurement is necessary since it is the most commonly measured physiological parameter often taken by doctor in order to assess the most basic body functions. 25

35 Chapter 3 DESIGN PROCEDURES This chapter describes the step-by step procedure used in developing the design and in development of the required program needed to make the prototype functional. It includes the detailed discussion of the three divisions such as hardware, software and prototype development. The procedures stated in this chapter allow readers, who are interested to further improve the design. Introduction The design project is entitled Android Based Application for Blood Pressure and Real Time Pulse Rate Monitor with SMS Alert Notification. The design uses a commercially available digital blood pressure and a heart rate circuit system, which was constructed by the researchers. The system has the ability to measure the blood pressure of the patient and monitor their heart rate in real time. For the blood pressure, data is extracted from the digital blood pressure, and transferring it to main system s MCU. Data is then processed and transferred to the android phone via Bluetooth. On the other hand, the heart rate circuit uses a sensor and an LED to measure the pulse rate of the patient. Data is also gathered by the MCU (the same MCU that gathers blood pressure data), and transfers it to the android phone also via Bluetooth. 26

36 USER HEART RATE BLOOD PRESSURE MCU BLUETOOTH MODULE BLUETOOTH SMART PHONE W/ANDROID OS DOCTOR/ PHYSICIAN FAMILY MEMBERS Figure 3.1: Conceptual Framework of Blood Pressure and Heart Rate Monitoring System Figure 3.1 shows the connection of each component of the system. User s heart rate reading is being requested by the MCU every second while the blood pressure is only requested only if the user will push the Inquire BP button in the application. Any request will be directly received by the MCU. Since only one MCU handles both request coming from the heart rate and blood pressure, it can be observed that there is a delay in displaying the blood pressure reading since the heart rate is requested every second. After the data have passed through the MCU, it will be passed on to the Bluetooth module for the transmission of data to the smart phone. The android application will then check if the measurements received are irregular, if it is, then it will send notifications to the user s doctor and family member. The design data gathering procedure as shown in Figure 3.2 starts with identifying and analyzing the problem on accuracy of data gathered and convenience of the device itself. In order for the researchers to solve the problem the next step is done which is the gathering of information from the previous related literature and various studies which can help in the development 27

37 of the solution. This part of the flowchart is very essential because this supplies the important information on how the problem can be solved. After acquiring enough information, the researchers then drafted for solutions which is to develop a device that can transfer data to a device such as smart phone for accessibility of both patient and doctor. Another is to create a real-time heart rate circuit which is supposed to gather precise reading of the pulse rate of patient. To prove the solution of the researchers, this device must be developed and tested whether or not it would function according to specifications. Knowledge acquired on the different capabilities and functionalities of individual components gave the researchers and edge on designing the prototype. Combining the materials together is an important process in order to see the outcome of the full system functionality. Calibration for the system is required when the LED displays low intensity of light; this is due to the factor that the characteristics such as thick skin or skin pigmentation will affect the performance of the pulse oximeter. To obtain accurate readings for the pulse rate, the multi-turn linear potentiometer should be calibrated so that the patient s pulse rate is synchronized with the blinking and the intensity of the light of the LED. 28

38 Start Identifying the problem: Accuracy, Convenience Researching and gathering of related literature and various studies No Data Gathered Useful? Yes Creating List of Solution to the Problem Gathering of Information on materials and various components need to design No Information appropriate? Yes Develop design Prototype End Figure 3.2: Design Data Gathering Procedure Flowchart 29

39 A. Hardware Development Figure 3.3: Block Diagram of Blood Pressure and Heart Rate Monitoring System As shown on figure 3.3, the input will be coming from the blood pressure and heart rate circuit obtained from the user. The systolic and diastolic values are obtained from the blood pressure once the start button is pressed on the blood pressure module, while continuous heart rate measurements are obtained from the heart rate circuit. All these data is passed on to a Bluetooth module, enabling wireless communication between the measuring devices and the output device. Lastly, the phone is the output device. In this design, the android phone is not only capable of displaying data, but is also capable of sending automated text messages to doctors or the patient s family members. 30

40 Schematic Diagram Figure 3.4: Blood Pressure and Heart Rate Monitoring System Schematic Diagram The circuit above depicts the main circuit of the system. A PIC184F4520 (DIL40) Microcontroller was used as the main controller of the system. It accepts the data from the heart rate circuit and the blood pressure module. The Bluetooth circuit allows the data gathered from the heart rate circuit and blood pressure module to be sent wirelessly to the android smart phone. To avoid fluctuations on the circuit s voltage input to the PIC184F4520 (DIL40) Microcontroller, a voltage regulator is placed in the circuit, otherwise known as IC It regulates a varying input voltage into a constant regulated output voltage. Another voltage regulator is placed in the circuit for the voltage input of the Bluetooth module. 31

41 Figure 3.5: Heart Rate Circuit Schematic Diagram The figure above shows the heart rate circuit. The output heart rate reading when measured by the circuit has a low magnitude, making it impossible for the microcontroller to read the data, and so we added an amplifier. LED is used to determine the calibration of the heart rate. The pulses on the LED should be synchronized with the user s oximeter pulses which can be felt when the oximeter is wrapped around the user s finger. Figure 3.6: Heart Rate Sensor Schematic Diagram 32

42 For the heart rate sensor circuit shown on figure, the designers used an infrared to detect pulsing arterial blood. This enables the system to determine the beats per minute measurement of the heart rate. B. Software Development The software development provides a description of the design of the application for Android Based Application for Pressure and Real-Time Pulse Rate Monitor with SMS Alert Notification. The programming part for the Microcontroller was developed using ProtonIDE which is similar to visual basic commands. The nature of the program is to gather data stored in the memory of the digital blood pressure and then transmit to the microcontroller then transfer the data to the android device with the help of Bluetooth unit. Meanwhile in order for the android phone to be able to communicate with the microcontroller it requires application software installed on the smart phone, the researchers apply the JAVA programming schemes deploying it on a particular software known as Basic4android. In Figure 3.7 (a) to (c), it displays the program flow of the proposed design system. The system starts when sufficient power is supplied. After powering on the device, the system is now ready and will initialize all of the variables, input ports and output ports in order to ready the necessary requirements for the other processes and to avoid unwanted and unstable states. After initializing the variables and ports, the restricted activity which can either be lying, standing or walking, is sent by the PC and is received by the wireless 33

43 module. A delay of 1 second is placed to ensure that no data loss occurs from the PC to the wireless module. After which, the current activity is detected by the microcontroller's interpretation of the accelerometer's input which can result to lying, standing or walking. A delay of 0.5 second is placed to properly process the data. Now, the microcontroller will check if the restricted activity is equal to the current activity, and will trigger on the buzzer if found true and will trigger off if not. After checking the restriction, the microcontroller will check if the current activity is not equal to the last activity. If it is equal, the value of the last activity will be replaced by the current activity. If it is not equal, the current activity will be sent to the PC through the wireless module. By this time, the system flow will repeat and will go back to the step where the restricted activity is obtained. As shown in Figure 3.7(a), assuming that the patient wishes to monitor their pulse rate first, the system starts by supplying the MCU with enough power to turn it on. When the MCU is turned on, the system will establish connection via Bluetooth connectivity, it will search for the available connection for the system to connect to. After the connection has been established the system s prerequisite is for the patient to input the necessary information, as soon as the information is saved in the database the user can precede to initial values of the readings which is set to initial value of 0 or to choose either to modify the existing record or to create new one. Once the patient proceeds to calibration, the system will display the pulse rate measurement. If the system calibration 34

44 fails, the system will recalibrate until it successfully acquires the data from the heart rate circuit. There is a small delay for the calibration to finish then values for the realtime heart rate will be displayed. It will then be stored on the database for record access purposes. The system will then compare the measured heart rate to the registered heart rate of the patient if the heart rate is above or below the assigned rate the system will send an SMS to the doctor/physician indicating irregular heart rate or pulse rate which can be seen on Figure 3.7 (b). The patient can choose to view history or to continue with the blood pressure monitor. If the patient selects the blood pressure monitor, the device must be on for the smart phone application to obtain data from the digital blood pressure device, as shown in figure 3.7 (c) the system will display the values from the device as long as the device is turned on, the system will fail to acquired data if the system is offline. The system performs comparison between assigned systolic and diastolic blood pressure and the measured values, the system will send an SMS if the patient has irregular blood pressure which is similar to heart rate. History viewing can be seen on figure 3.7 (a), the gathered numbers are stored in an individual patient record with data and time of the patient s diagnosis. 35

45 Start MCU turned on? Establish Connection with Bluetooth No Reconnect No Yes Input Patient s Information Yes Login Information Complete? No Modify and Save on Database Yes Tapped Start Calibration on Android Application Display Reading No Calibration Success? Recalibrate 1 Yes No Real Time Display of HR Values Save Record to Database ShowBP button Tapped View History Tapped Yes No 3 Exit? 2 Yes Figure 3.7: Flow chart diagram of the system (a) 36

46 2 Is the heart rate normal No Heart Rate Above or Below Assigned Rate No No Yes Yes Send Message 1 and 2 Exit? No 1 Yes End Figure 3.7: Flow chart diagram of the system (b) 37

47 3 No Check Device Connected Reconnect Yes Display Blood Pressure Values Save Record to Database Blood Pressure Above or Below Assigned Rate No Yes Send Message 1 and 2 Exit? No 1 Yes End Figure 3.7: Flow chart diagram of the system (c) 38

48 Data Model Figure 3.8: Case Model Diagram The figure above shows the case model of the system. It displays the basic functionalities of the system. Initially, the user is capable of doing three functionalities; create a patient record, measure blood pressure and heart rate, and to display previous records/readings. Two of these tasks have sub-processes that could be done upon choosing the task. For the measurement of the BP and heart rate, real time measurement of the heart rate is obtained once the smart phone is connected to the device via Bluetooth, and blood pressure can be obtained by pressing the inquire BP button on the smart phone. For the display of the readings/records, the latest blood pressure and heart rate reading can be viewed, and lastly, the logs, which contains the time when the data is acquired. 39

49 C. Prototype Development Hardware Components Figure 3.9: PIC18F4520 (DIL40) Microcontroller This is the main controller of the system. The PIC18F4520 (DIL40) Microcontroller is responsible for sending and synchronizing the data from the heart rate and blood pressure to the smart phone via the Bluetooth module. Figure 3.10: Watsons Digital Blood Pressure For the blood pressure, we used a commercially available digital blood pressure from Watsons. For the design, we extracted the output data of the blood pressure readings by redirecting its output data to the PIC18F4520 (DIL40) Microcontroller. 40

50 Figure 3.11: Bluetooth Module The Bluetooth module enables the system the capability to pass data from the MCU to the Android smart phone wirelessly. It is directly connected to the MCU, and its input voltage comes from a voltage regulator RT9163 IC. Figure 3.12: 7805 IC The 7805IC is a voltage regulator used for providing a constant regulated output for the circuit. This IC is used for regulating the voltage input for the PIC184F4520 (DIL40) Microcontroller. Figure 3.13: LM324N IC The LM324N IC is an op amp that has been used to increase the signal strength of the data from the heart rate circuit. Data directly produced from the heart rate circuit is too small for the MCU, hence amplification is necessary. 41

51 Figure 3.14: RT9163 IC The RT9163 IC is another voltage regulator just like the 7805IC. This voltage regulator was used to provide a constant regulated input voltage for the Bluetooth module. PCB Layout Figure 3.15: Blood Pressure and Real-Time Pulse Rate Monitor Circuit PCB layout 42

52 Figure 3.16: Heart rate PCB Layout Figure 3.17: Bluetooth PCB Layout The following statements summarize the development of the Android Based Application for Pressure and Real-Time Pulse Rate Monitor with SMS Alert Notification. 1. Submission of project proposal. 2. Data gathering related literature and related studies 43

53 3. Research on how the major components function: a. Digital Blood Pressure b. Real-Time Pulse Rate c. Oximeter d. Android Software e. JAVA f. Basic4Android g. Microcontroller 4. Development of the design outline for Android Based Application for Pressure and Real-Time Pulse Rate Monitor with SMS Alert Notification. 5. Study on the operation and parts of the Android Based Application for Pressure and Real-Time Pulse Rate Monitor with SMS Alert Notification. 6. Designing of the device based on the design flowchart. 7. Testing of the device if it is able to function properly and accordingly to the requirements. 8. Debugging the software for necessary bugs affecting the device. 9. Modification and improvements on the casing of device and reduce the noise propagation of the Bluetooth module. 10. Testing the device on the patient. 44

54 Chapter 4 TESTING, PRESENTATION, AND INTERPRETATION OF DATA I. Comparing Display on Blood Pressure Monitor Device and Android Application This digital blood pressure device is designed to monitor and display the cuff pressure during cuff inflation and deflation. The blood pressure is checked by measuring the changes in the motion of the artery as the blood flows through the artery while the cuff deflates. To conduct the test, the procedure below was followed. (Sari Hardyal, 2011). Procedures 1. The patient has to be relax sitting on a chair with his/her arm resting comfortably on a table at approximately heart height. Have the patient roll up his/her sleeve so the sphygmomanometer can be put on the bare skin of the arm. 2. Place the sphygmomanometer on the arm, lining up the appropriate line on the device with the brachial artery. There is a designation on the cuff of the sphygmomanometer that shows where to align the left or right brachial artery. Attach the cuff's Velcro so the cuff is wrapped comfortably around the patient's arm. 45

55 3. Turn on the digital blood pressure, and then press the Start button. The cuff will automatically inflate and after the reading is displayed it will automatically deflate. 4. The blood pressure readings will be displayed on the device s monitor. The systolic blood pressure corresponds to the number that is on top when recording the blood pressure. Diastolic blood pressure is the number that is at the bottom when recording blood pressure. 5. Using android phone with the heart rate monitor application, press scan device to search for the Bluetooth device connected to the microcontroller and connect to Linvor, the name assigned to the device s Bluetooth connection. 6. Once connected, the application will indicate the connectivity of the device; it will prompt the patient to create new patient record or use the existing patient record then tap the name twice to login. 7. Then tap the inquire BP button to acquire the data from the blood pressure device.. 8. Automatically the application will display the corresponding reading of blood pressure which was obtained from the blood pressure monitoring device. 9. After deflation, slowly remove the blood pressure s cuff from the patient. 46

56 After following the procedure, the data gathered was filled in the table below. We used this limit for all the users: (Based from the Philippine Society of Hypertension) Blood Pressure (Systolic) Blood Pressure (Diastolic) 140 mmhg 90 mmhg Table 4.1: Standard Blood Pressure Level of Normal Patient Patient No. Blood Pressure Monitor Device Android Application Text Message (if irregular) Systolic Pressure (mmhg) Diastolic Pressure (mmhg) Systolic Pressure (mmhg) Diastolic Pressure (mmhg) No No No No No No No No No Yes Yes No Yes No Yes Yes No Yes No No Table 4.2: Blood Pressure Test Table 47

57 The data gathered in table 4.2, presents the reading of the blood pressure device for the 20 patients. As observed from the table, data displayed on the device and the inquired values on the android application are the same. Based on the results, there are 6 patients which have irregular blood pressure that exceeds the set standards as shown on Table 4.1, while there are 14 patients which has regular blood pressure. The SMS function of the smart phone will activate when the recording data of the patients exceed the standard blood pressure level of a normal patient as shown on Table 4.1. Refer to Appendix E for abnormal readings of the blood pressure both systolic and diastolic pressure. II. Testing the Real-Time Pulse Rate Measurement Accuracy The pulse oximeter is an early-warning device that continuously measures the level of oxygen saturation of hemoglobin in the arterial blood. It can detect hypoxia much sooner than the anesthesia provider can see clinical signs of hypoxia such as cyanosis. This ability to provide early warning has made the pulse oximeter essential for safe anesthesia. (World Health Organization, 2011) Procedures 1. The patient has to be relax sitting on a chair with his/her arm resting comfortably on a table at approximately heart height. Place the Velcro in the bare skin index finger of the patient; it must be properly layered so the sensor will have precise reading of the pulse rate. 48

58 2. Calibrate the potentiometer s knob. Two knobs can be seen from device. The left knob is to adjust the speed in which the LED blinks, and the right knob is for the intensity of the light produced by the LED. 3. Using android phone with the heart rate monitor application, press scan device to search for the Bluetooth device connected to the microcontroller and connect to Linvor the name assigned to the device s Bluetooth connection. 4. Once connected, the application will indicate the connectivity of the device; it will prompt the patient to create new patient record or use the existing patient record then tap the name twice to login. 5. Then tap the start button to initialize the calibration of the pulse rate, it will indicate a correct reading if the android application displays the reading acquired, otherwise it will display recalibrate the system. If calibration failed in reading try to attune the knobs so that the reading can be identified by the device. Press Stop if the patient has not adjusted the knob before starting the calibration of pulse rate. 6. The application will display real-time reading of pulse rate, this reading will be stored on the database of the android application, and can be accessed by the patient in order to view their record. 7. Slowly remove the heart rate s cuff from the patient. 49

59 After following the procedure, the table below was filled in. Patient No. Heart Rate Monitor (bpm) Android Application Via pulse oximeter (bpm) Text Message (if irregular) No No Yes No No No No No No Yes No No No Yes No Yes No No No No Table 4.3: Heart rate Test Table Table 4.3 shows the relevance of the heart rate measured from the digital blood pressure device and the android application using the pulse oximeter probe. The values suggest that there is a difference that can be used and be utilized in differentiating the digital blood pressure and the android application using pulse oximeter in gathering the patients pulse rate. With the readings obtained for each individual patient are acceptable due to the factor the 50

60 pulse rate oximeter measurements updates the values according to the pulse rate of the patient in real-time unlike the fixed measurement of pulse rate for the digital blood pressure device. With respect to the SMS function, it will only trigger when the irregular heart rate either exceeds the set values or is less than the set low pulse rate for a normal patient pulse rate reading. Data gathered for each patient refer to the table above that indicates that 4 out of 20 patient volunteered in testing have irregular heart rate which exceeds the limit of 120 bpm (beats per minute) of the standard pulse rate of individual patient. Refer to Appendix F for further information of the details regarding normal pulse rate of an individual person. Chapter 5 CONCLUSION AND RECOMMENDATION This chapter provides the conclusions of the researcher after designing the Android Based Application for Pressure and Real-Time Pulse Rate Monitor with SMS Alert Notification device through testing and analysis. Accordingly, the device has room for suggestions to enhance by future researchers. Conclusion In terms of blood pressure and heart rate monitoring, the design has successfully met this objective. The design was able to measure blood pressure and heart rate and notifies two people simultaneously whenever an irregular reading has been received by the smartphone application. The tests conducted by the designers show the effectiveness of the device by comparing the output 51

61 of the designed pulse oximeter to a commercially available pulse oximeter. It has been observed that their difference is almost negligible; it s just that the commercially available pulse oximeter s reading is more stable than the design made. Perhaps, some changes in the calibration algorithm must be done to come up with a more precise measurement. Aside from that, other functionalities of the design were perfectly done. The SMS notification prompts immediately before you can see the irregular heart rate or blood pressure reading. A history file of all the readings was also made for later preferences of the patient. Some limitations were observed from the device, since the heart rate is being transmitted every second, if a patient will request for a BP reading, there will be a delay because they are using the same microcontroller and Bluetooth module for transmitting the data to the smart phone application. Also, during testing procedures, it has been observed that signal being omitted by the Bluetooth module affects measurement done by the heart rate circuit, that is why we separated the casing of the Bluetooth module from the rest of the circuit and made the wiring between them a bit long so that we can move it a little further from each other. Doing so prevented the measurement of the heart rate for being interfered by Bluetooth signals. The device would aide doctors and hospitals in monitoring heart rate and blood pressure of patients in remote locations especially those who are in critical conditions and are in need of constant monitoring and periodic. 52

62 Recommendation The design has accurate readings and good functionalities but there is still room for improvement. The recommendations are as follows: 1. Make a more stable calibration algorithm for heart rate measurement. 2. Minimize size of device incorporating future technology such as nanotechnology. 3. Improve the algorithm in saving in the history file by removing redundant entries. 4. Attach knobs in the potentiometers or place them outside the casing for easier calibration. 5. Incorporate new Smartphone technology such as Near-Field Communication for faster connection between the device and the smart phone. 6. Include information in the patient s database such as present location, age, etc. 7. Include a function which allows the patient to add more than two numbers (if desired) were notifications will be sent. BIBLIOGRAPHY Jiehui Jiang, Zhuangzhi Yan, Jun Shi, Prabhu Kandachar and Adinda Freudenthal (2010), A Mobile Monitoring System of Blood Pressure for Underserved in China Information and Communication Technology Service David Reid, Heidi Robertson and Matthew Sonntag (2011), Pulse Oximeter Calibrator 53

63 Adisorn Sirikham(2010), Abnormal Heart Rate Detection Device Warning via Mobile Phone Network Jiehui Jiang, Zhuangzhi Yan, Jun Shi, and Prabhu Kandachar (2008), Design of Wireless Mobile Monitoring of Blood Pressure for Underserved in China by Using Short Messaging Service Salys Sultan and Permanand Mohan (2009), How to Interact: Evaluating the Interface between Mobile Healthcare Systems and the Monitoring of Blood Sugar and Blood Pressure Lisheng Xu, Xu Guo, Feifei Yang, Sainan Yin, Xibin Zhang and Max Q.-H. Meng (2012), Implementation of Cuff-less Continuous Blood Pressure Measurement System Based on Android U Kin Che, Chi Kin Lao, Sio Hang Pun, Peng Un Mak, Feng Wan, and Mang I Vai (2012), Portable Heart Rate Detector Based on Photoplethysmography with Android Programmable Devices Wan-Young Chung, Seung-Chul Lee and Sing-Hui Toh(2008), WSN Based Mobile u-healthcare System with ECG, Blood Pressure Measurement Function Antti Konttila, Miia Määttälä and Esko Alasaarela (2003), Pulse Oximeter Signal Amplitudes in Different Body Parts for Wireless Solutions Ashraf Tahat, Anwar Sacca and Yazeed Kheetan (2011), Design of an Integrated Mobile System to Measure Blood Pressure 54

64 APPENDIX A Operation s Manual 1. First, connect all the devices. Connect the rubber tube to the digital blood pressure device and the pulse oximeter to the heart rate device. Then, attach the battery at the back of the heart rate device. 2. Wear the blood pressure cuff in your upper left or right arm. The rubber tube must be aligned in the center palm to have an accurate reading. 3. Wear the pulse oximeter in any of your finger which fits it best. The red LED light and the photodiode must be facing each other and it must be tightly wrapped to your finger. 4. If the attachment of pulse oximeter is tight enough, you should be feeling the beat of you pulse. If you do, check if your pulse is in rhythm with the blinking LED light in front of the heart rate device. If you do not, reattach the pulse oximeter. 5. If your pulse is in rhythm with the LED light, then you are ready to start the application but if it is not in rhythm, then adjust the potentiometer in the heart rate device. 6. Now, start the android application and then add a new patient record. Fill in all the needed information carefully. 7. After that, go back to the main menu and push the Use Selected button. 8. Then it will ask if you want to open the Bluetooth connection, choose Yes. 55

65 9. Push the Start button to start the heart rate calibration. If it did not fail then the reading must be displayed in the screen. If the calibration fails, it will ask you if you want to recalibrate, choose Yes, if it continues to fail, try to reset the heart rate device and the android app. 10. To display and record your blood pressure in the app, power on the digital blood pressure. Place the cuff on the upper half of the arm and press the start button on the blood pressure. Afterwards, the results will be displayed on the blood pressure monitor. For the results to be transferred on the smart phone, press the Inquire BP button on the application. 11. To see previous records, push the View History button. 12. To modify and delete patient record, you must go back to the main menu and then push the Modify Database button. 1. System Requirement Here are the requirements necessary to operate the device. It should be a smart phone with the following features: a. Android Operating System : Android Gingerbread and above b. Bluetooth Connection c. Minimum Memory of 512MB. 2. Installation Procedure 1) Copy the MITBP.apk file located in the CD included in the package anywhere in your android phone s memory. 56

66 2) Then open the file to install it. 3) You must agree to the following questions to able to install it. Safety Precautions Statements provided below indicate pointers to prevent hazards from users when handling the unit: If one is using a power supply, never attempt to plug or unplug the power outlet when one s hand is wet. Push the plug all the way into the power outlet. If one prefers to use battery, never attempt to connect the battery with wet hands. Do not touch the battery while in use. Caution Statements provided below indicate pointers for the unit safety handling to prevent hardware complications: The device is Electrostatic discharge (ESD) sensitive. Improper handling may result to damage. Do not touch any of the electronic components of the device placed inside the package. Do not place heavy objects on the device. Keep the device away from hot objects. Store the device in a cool, safe place to prevent damage. 57

67 Never use any power supply greater than the required:12v Observe the correct placement of the battery. Wrong placement of polarity will damage the components of the unit. Handle the unit with care. Do not drop the hardware. 3. User s Manual Device Description Measures your blood pressure and heart rate and display the result in your Android phone. Your blood pressure reading is by-request. Your heart rate is being monitored continuously. Notifies your relatives and doctor if any irregular reading has been received. You can modify the blood pressure and heart rate limits. Every reading is being saved in a text file. 4. Troubleshooting Guides and Procedures In adjusting the potentiometers, it is easier to adjust only one potentiometer to have a precise reading. Using other power supply other than rechargeable batteries may affect the reading of the heart rate because it may have some noise to it. If your heart rate is too far from the normal, it can be caused by improper wrapping of the pulse oximeter in your 58

68 finger, reattaching it may help. Find the finger which best fitted the pulse oximeter, meaning that the LED light and the photodiode are facing each other. 5. Error Definitions An error reading in your BP means that you are not seated properly or the cuff is not properly wore in your arm. An error in heart rate calibration means that the pulse oximeter is not placed properly. A Generic Error means that the SIM (Subscriber Identity Module) card, the user is using does not have credit of his/her phone. This occurs when the application tries to send a notification to someone but failed to do it due to insufficient amount. 59

69 APPENDIX B Pictures of Prototype Picture of the whole system including the digital blood pressure, oximeter, and the smart phone 60

70 Picture of the system when turned on The smart phone in the process of calibrating with the device Connection Successful with the device 61

71 The digital blood pressure determining the systolic pressure of a user Measurements of the blood pressure displayed on the digital blood pressure, including the user s heart rate 62

72 APPENDIX C Data Sheet 63

73 64

74 65

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76 67

77 68

78 69

79 70

80 71

81 72

82 73

83 74

84 APPENDIX D Source Code PIC18Microntroller using Proton IDE Device 18F4520 Declare Xtal 20 Declare Watchdog = OFF Declare FSR_CONTEXT_SAVE = On Remarks On Declare Unsigned_Dwords On Declare SERIAL_DATA 8 Declare Hserial_Baud = 9600 Declare Hserial_RCSTA = % Declare Hserial_TXSTA = % Declare Hserial_Clear = On Declare Adin_Res 8 Declare Adin_Tad 2_FOSC Declare Adin_Stime 50 Symbol TMR0IF = INTCON.2 ' TMR0 Overflow Interrupt Flag Symbol TMR0IE = INTCON.5 ' TMR0 Overflow Interrupt Enable Symbol GIE = INTCON.7 ' Global Interrupt Enable Symbol BPReadSW = PORTD.6 Dim intctr As Dword Dim dsdelay As Byte, hrbpm As Dword Dim dsdctr As Byte intctr = 0 dsdelay = 0 dsdctr = 0 On_Interrupt GoTo ihandler GoTo preprog ihandler: Context Save If TMR0IF = 1 Then Inc intctr Inc dsdctr EndIf If dsdctr > 100 Then Inc dsdelay dsdctr = 0 EndIf TMR0IF = 0 Context Restore 75

85 preprog: T0CON = $C2 ADCON1 = $00 ADCON2.7 = 0 TRISA = $FF TRISB = $FF TRISC = $BF TRISD = $BF TRISE = $07 BPReadSW = 1 Dim tread As Byte, mytempa As Dword Dim mytemp As Float Dim myhr As Byte Dim dbuffer[7] As Byte, systolic As Byte, diastolic As Byte, bpm As Byte Dim gctr As Word Dim dirc As Byte Dim dummy As Float Dim asamps1[255] As Byte Dim maxid As Byte, maxbpmc As Byte, ubpm As Byte, lbpm As Byte Dim amax As Byte Dim ulimit As Byte Dim llimit As Byte Dim startid As Word Dim endid As Word Dim mfailure As Byte Dim bfailure As Byte Dim hrdiff As Byte, hrprev As Byte DelayMS 500 mytemp = 0 myhr = 0 systolic = 0 diastolic = 0 DelayMS 2000 While 1 = 1 HSerIn[Wait("ABP"),dirC] Select Case dirc Case "B" 'BP Request GoSub readbp bpsr: HSerOut["ABP",Dec3 systolic, Dec3 diastolic, Dec3 myhr] HSerIn 5000,bpSR,[Wait("AOK")] Case "H" 'Heartrate GoSub readhr 76

86 hrdiff = Abs (bpm - hrprev) If bpm = 0 Then 'recalibrate! GoSub HRCalibrate GoSub readhr ElseIf hrdiff > 5 Then If bfailure < 3 Then Else Inc bfailure 'recalibrate! GoSub HRCalibrate GoSub readhr EndIf Else bfailure = 0 hrprev = bpm Print At 2,7,Dec3 bpm EndIf hrsr: HSerOut["AHR", Dec3 bpm] HSerIn 5000,hrSR,[Wait("AOK")] Case "C" GoSub HRCalibrate GoSub readhr clbsr: HSerOut["AHR", Dec3 bpm] 'HSerOut["AMAX=", DEC5 AMAX] HSerIn 5000,clbSR,[Wait("AOK")] EndSelect Wend readhr: While GIE = 1 : GIE = 0 : Wend TMR0L = 0 77

87 TMR0H = 0 TMR0IE = 1 GIE = 1 While TMR0H > 0 And TMR0L > 0 Wend dsdctr = 0 dsdelay = 0 While dsdelay < 75 tread = ADIn 0 If tread <= ulimit And tread >= llimit Then EndIf GoTo readdelay 'print At 2,1,Dec5 amax, 32, Dec5 tread,32, Dec5 dsdelay Wend bpm = 0 If mfailure < 255 Then Inc mfailure EndIf GoTo HREnd readdelay: intctr = 0 dsdctr = 0 dsdelay = max 145 bpm While dsdelay < 10 Wend readnext: dsdctr = 0 dsdelay = 0 While dsdelay < 75 tread = ADIn 0 If tread <= ulimit And tread >= llimit Then hrbpm = intctr GoTo HROK EndIf 'Print At 3,1,Dec5 amax, 32, Dec5 tread,32, Dec5 dsdelay Wend bpm = 0 If mfailure < 255 Then Inc mfailure EndIf 78

88 GoTo HREnd HROK: dummy = intctr * dummy = / dummy hrbpm = dummy bpm = hrbpm mfailure = 0 HREnd: dsdctr = 0 dsdelay = 0 While dsdelay < 10 Wend While GIE = 1 : GIE = 0 : Wend TMR0L = 0 TMR0H = 0 TMR0IE = 0 GIE = 0 Return HRCalibrate: While GIE = 1 : GIE = 0 : Wend TMR0L = 0 TMR0H = 0 TMR0IE = 1 GIE = 1 While TMR0H > 0 And TMR0L > 0 Wend intctr = 0 dsdctr = 0 dsdelay = 0 amax = 0 ulimit = 0 llimit = 0 maxid = 0 maxbpmc = 0 For gctr = 0 To 254 asamps1[gctr] = 0 Next gctr While 1 = 1 'If intctr > Then 79

89 If intctr > 4902 Then Else EndIf Wend 'verify amax for valid measurement GoTo maxgetok tread = ADIn 0 Inc asamps1[tread] DelayUS 5 maxgetok: amax = 255 maxid = 0 For gctr = 1 To 254 If amax > asamps1[gctr] And asamps1[gctr] > 15 Then amax = asamps1[gctr] maxid = gctr EndIf Next gctr amax = maxid ulimit = amax + 2 If amax > 1 Then llimit = amax - 2 Else llimit = 0 EndIf 'bpm = 0 bfailure = 0 mfailure = 0 While GIE = 1 : GIE = 0 : Wend TMR0L = 0 TMR0H = 0 TMR0IE = 0 GIE = 0 Return readbp: BPReadSW = 0 DelayUS 10 BPReadSW = 1 systolic = 0 80

90 diastolic = 0 myhr = 0 SerIn PORTD.7,84,2000,readBPComplete,[Wait("DATA"), systolic, diastolic, bpm] readbpcomplete: Return End Android Application using Basic4Android Main 'Activity module Sub Process_Globals Dim DBFileName As String Dim DBFileDir As String Dim DBTableName As String Dim SQL1 As SQL : DBFileName = "cbhrbp.db" : DBFileDir = File.DirDefaultExternal : DBTableName = "tblsysusers" Dim Serial1 As Serial Dim connected As Boolean Dim BulToot As BluetoothAdmin Dim AStreams As AsyncStreams Dim BtIsOn As Boolean Dim mpcallintent As PhoneCalls Dim mpsmsintent As PhoneSms Dim mpphoneevent As PhoneEvents Dim pid As String : pid = "0" Dim pname As String : pname = "No Name" Dim psmsnum1 As String : psmsnum1 = "" Dim psmsnum2 As String : psmsnum2 = "" Dim pcallnum As String : pcallnum = "" Dim phrhi As String : phrhi = "" Dim phrlo As String : phrlo = "" Dim pbphi As String : pbphi = "" Dim pbplo As String : pbplo = "" Dim Systolic As String : Systolic = "000" Dim Diastolic As String : Diastolic = "000" Dim BPStr As String : BPStr = "000" Dim myhr As String : myhr = "000" Dim myhri As Int : myhri = 0 Dim reqtype As String : reqtype = "H" Dim smshrc As Int : smshrc = 5 Dim smsbpc As Int : smsbpc = 5 Dim HRPrev As Int : HRPrev = 0 Dim mytimer As Timer Dim mylogger As Timer End Sub Sub Globals Dim StrBuff01 As String Dim lblbp As Label Dim lblconstat As Label Dim lblhr As Label Dim btlist As List 81

91 Dim macaddtable As List Dim lblpname As Label Dim btninquirebp As Button Dim btnstartstop As Button Dim btncalib As Button ' Dim Systolic As String : Systolic = "000" ' Dim Diastolic As String : Diastolic = "000" ' Dim BPStr As String : BPStr = "000" ' Dim myhr As String : myhr = "000" ' Dim myhri As Int : myhri = 0 ' Dim reqtype As String : reqtype = "H" ' Dim smshrc As Int : smshrc = 5 ' Dim smsbpc As Int : smsbpc = 5 ' Dim HRPrev As Int : HRPrev = 0 Dim mysmsexec As Int : mysmsexec = 0 Dim mysmstype As Int : mysmstype = 0 Dim Writer As TextWriter End Sub Sub Activity_Create(FirstTime As Boolean) If FirstTime Then Serial1.Initialize("Serial1") End If 'If File.Exists(File.DirDefaultExternal, DBFileName) = False Then ' DBFileDir = DBUtils.CopyDBFromAssets(DBFileName) 'End If SQL1.Initialize(DBFileDir, DBFileName, True) Dim mymap As Map mymap.initialize mymap.put("userid",dbutils.db_integer) mymap.put("username",dbutils.db_text) mymap.put("usersms1",dbutils.db_text) mymap.put("usersms2",dbutils.db_text) mymap.put("usercall",dbutils.db_text) mymap.put("userhrhi",dbutils.db_text) mymap.put("userhrlo",dbutils.db_text) mymap.put("userbphi",dbutils.db_text) mymap.put("userbplo",dbutils.db_text) mytimer.initialize("mytimer",1000) mytimer.enabled = False mylogger.initialize("mylogger",1000) mylogger.enabled = False DBUtils.CreateTable(SQL1,DBTableName, mymap,"") 'StartActivity(mpCallIntent.Call(" ")) Activity.LoadLayout("1") Activity.Title = "Heart Rate Monitor" Activity.AddMenuItem("Connect", "mnuconnect") Activity.AddMenuItem("Scan Devices", "mnuscandev") Activity.AddMenuItem("Disconnect", "mnudisconnect") Activity.AddMenuItem("Change User", "mnuchangeuser") BulToot.Initialize("BulToot") StrBuff01 = "" 82

92 BtIsOn = BulToot.IsEnabled lblconstat.textcolor = Colors.Red lblconstat.text = "Disconnected" lblpname.text = "" StartActivity("showData") End Sub Sub Activity_Resume lblpname.text = pname mpphoneevent.initialize("pe_events") If Serial1.IsEnabled = False Then BTConnect Else Serial1.Listen 'listen for incoming connections End If End Sub Sub PE_Events_SmsSentStatus (Success As Boolean, ErrorMessage As String, PhoneNumber As String, Intent As Intent) If Success = True Then If mysmsexec = 1 Then Select Case mysmstype Case 1 ProgressDialogShow("Sending SMS Alert 2, Irregular HeartRate") & ")") mpsmsintent.send(psmsnum2,"patient " & pname & " has irregular heartrate (" & myhr Case 2 ProgressDialogShow("Sending SMS Alert 2, Irregular BP") mpsmsintent.send(psmsnum2,"patient " & pname & " has irregular blood pressure (" & Systolic & "/" & Diastolic & ")") End Select Else Else End If mysmsexec = 2 ProgressDialogHide mysmsexec = 0 reqtype = "H" mytimer.enabled = True mysmsexec = 0 83

93 End If ToastMessageShow(ErrorMessage,False) End Sub Sub mnuchangeuser_click StartActivity("showData") End Sub Sub mnuscandev_click If BtIsOn = False Then BTConnect Else BulToot.StartDiscovery End If End Sub Sub mnuconnect_click Dim PairedDevices As Map PairedDevices = Serial1.GetPairedDevices Dim l As List l.initialize If PairedDevices.Size > 0 Then Else End If End Sub For i = 0 To PairedDevices.Size - 1 l.add(paireddevices.getkeyat(i)) Next Dim res As Int res = InputList(l, "Choose device", -1) 'show list with paired devices If res <> DialogResponse.CANCEL Then Serial1.Connect(PairedDevices.Get(l.Get(res))) 'convert the name to mac address End If Msgbox("There are no devices currently paired to the device." & CRLF & _ "Please select scan to get a list of available devices.","paired Devices Missing!") Sub Serial1_Connected (Success As Boolean) If Success Then ToastMessageShow("Connected successfully", False) AStreams.Initialize(Serial1.InputStream,Serial1.OutputStream,"AStreams") lblconstat.textcolor = Colors.Green lblconstat.text = "Connected" 84

94 connected = True StrBuff01 = Chr(13) AStreams.Write(StrBuff01.GetBytes("UTF8")) StrBuff01 = "" Else connected = False 'Timer1.Enabled = False Msgbox(LastException.Message, "Error connecting.") End If End Sub Sub mnudisconnect_click AStreams.Close Serial1.Disconnect lblconstat.textcolor = Colors.Red lblconstat.text = "Disconnected" ToastMessageShow("Connection Disconnected", False) connected = False End Sub Sub Activity_Pause (UserClosed As Boolean) mpphoneevent.stoplistening If UserClosed = True Then End If AStreams.Close Serial1.Disconnect BulToot.Disable End Sub Sub AStreams_NewData (Buffer() As Byte) Dim msg As String msg = BytesToString(Buffer, 0, Buffer.Length, "UTF8") StrBuff01 = StrBuff01 & msg If StrBuff01.Contains("ABP") = True AND StrBuff01.StartsWith("ABP") = False Then StrBuff01 = "ABP" Else If StrBuff01.Contains("ABP") = True AND StrBuff01.StartsWith("ABP") = True Then If StrBuff01.Length >= 12 Then ProgressDialogHide Systolic = StrBuff01.SubString2(3,6) Diastolic = StrBuff01.SubString2(6,9) 'lblhr.text = BPStr & " BPM" lblbp.text = Systolic & " / " & Diastolic StrBuff01 = "AOK" Buffer = StrBuff01.GetBytes("UTF8") AStreams.Write(Buffer) StrBuff01 = "" 85

95 If Systolic > pbphi OR Systolic < pbplo Then 'If smsbpc = 0 Then ProgressDialogShow("Sending SMS Alert 1, Irregular BP") mysmstype = 2 mpsmsintent.send(psmsnum1,"patient " & pname & " has irregular blood pressure (" & Systolic & "/" & Diastolic & ")") mysmsexec = 1 smsbpc = smsbpc + 1 'Else If smsbpc < 5 Then ' smsbpc = smsbpc + 1 'Else ' smsbpc = 0 'End If Else If Diastolic > pbphi OR Diastolic < pbplo Then 'If smsbpc = 0 Then ProgressDialogShow("Sending SMS Alert 1, Irregular BP") mysmstype = 2 mpsmsintent.send(psmsnum1,"patient " & pname & " has irregular blood pressure (" & Systolic & "/" & Diastolic & ")") mysmsexec = 1 smsbpc = smsbpc + 1 Else End If 'Else If smsbpc < 5 Then ' smsbpc = smsbpc + 1 ' reqtype = "H" ' mytimer.enabled = True ' mysmsexec = 0 'Else ' smsbpc = 0 ' reqtype = "H" ' mytimer.enabled = True ' mysmsexec = 0 'End If smsbpc = 0 reqtype = "H" mytimer.enabled = True mysmsexec = 0 End If Else If StrBuff01.Contains("AHR") = True AND StrBuff01.StartsWith("AHR") = False Then StrBuff01 = "AHR" Else If StrBuff01.Contains("AHR") = True AND StrBuff01.StartsWith("AHR") = True Then 86

96 If StrBuff01.Length >= 6 Then myhr = StrBuff01.SubString2(3,6) myhri = myhr lblhr.text = myhr & " BPM" lblbp.text = Systolic & " / " & Diastolic StrBuff01 = "AOK" Buffer = StrBuff01.GetBytes("UTF8") AStreams.Write(Buffer) StrBuff01 = "" If reqtype = "C" Then ProgressDialogHide If myhri = 255 OR myhri = 145 Then Then If Msgbox2("Calibration Failed. Retry?","Error!","Yes","","No",Null) = DialogResponse.POSITIVE End If mytimer.enabled = True Else Writer.Initialize(File.OpenOutput(File.DirDefaultExternal, pname & ".txt",true)) Writer.WriteLine("Logging Started: " & DateTime.Date(DateTime.Now) & ", " & DateTime.Time(DateTime.now)) Writer.WriteLine(DateTime.Time(DateTime.now) & ":" & "BP- " & Systolic & "/" & Diastolic & " HR- " & myhr & " BPM") Writer.Close HRPrev = myhri reqtype = "H" mytimer.enabled = True mylogger.enabled = True Else End If If myhri = 0 Then ProgressDialogShow("Calling for Help, Heart Attack Detected!") StartActivity(mpCallIntent.Call(pCallNum)) Else If myhri > phrhi OR myhri < phrlo Then If smshrc = 0 Then & ")") ProgressDialogShow("Sending SMS Alert 1, Irregular HeartRate") mysmstype = 1 mpsmsintent.send(psmsnum1,"patient " & pname & " has irregular heartrate (" & myhr mysmsexec = 1 smshrc = smshrc + 1 Else If smshrc < 5 Then Else smshrc = smshrc + 1 reqtype = "H" mytimer.enabled = True mysmsexec = 0 87

97 End If Else End If smshrc = 0 reqtype = "H" mytimer.enabled = True mysmsexec = 0 reqtype = "H" mytimer.enabled = True mysmsexec = 0 End If End If End If End Sub Sub AStreams_Error 'ToastMessageShow(LastException.Message, True) 'close everything. Msgbox("Data Connection Error. Please Check Bluetooth Connectivity","Fatal Error" ) End Sub Sub BTConnect As Boolean If Msgbox2("Enable Bluetooth?","Bluetooth Required","Yes","","No", Null) = DialogResponse.POSITIVE Then Else BulToot.Enable Return True Return False End If End Sub Sub BulToot_DiscoveryStarted End Sub ProgressDialogShow("Scanning Devices..") btlist.initialize macaddtable.initialize Sub BulToot_DiscoveryFinished ProgressDialogHide 88

98 End Sub Dim res As Int res = InputList(btList, "Choose device", -1) 'show list with paired devices If res <> DialogResponse.CANCEL Then Serial1.Connect(macAddTable.Get(res)) 'convert the name to mac address End If Sub BulToot_DeviceFound (Name As String, MacAddress As String) End Sub 'ToastMessageShow(Name & ":" & MacAddress,False) ProgressDialogShow("Detected: " & Name & ":" & MacAddress) btlist.add(name) macaddtable.add(macaddress) Sub BulToot_StateChanged(NewState As Int, OldState As Int) If NewState = BulToot.STATE_TURNING_ON Then ProgressDialogShow("Turning On Bluetooth.") Else If NewState = BulToot.STATE_ON Then ProgressDialogHide ToastMessageShow("Bluetooth Enabled",False) BtIsOn = True Else If NewState = BulToot.STATE_OFF Then End If End Sub Sub mylogger_tick ToastMessageShow("Bluetooth Disabled",False) BtIsOn = False Activity.Title = DateTime.Time(DateTime.Now) If reqtype = "B" Then " BPM") Writer.Initialize(File.OpenOutput(File.DirDefaultExternal, pname & ".txt",true)) Writer.WriteLine(DateTime.Time(DateTime.now) & ":" & "BP- " & Systolic & "/" & Diastolic & " HR- " & myhr & Writer.Close Else If reqtype = "H" Then If myhr <> HRPrev Then Writer.Initialize(File.OpenOutput(File.DirDefaultExternal, pname & ".txt",true)) Writer.WriteLine(DateTime.Time(DateTime.now) & ":" & "BP- " & Systolic & "/" & Diastolic & " HR- " & myhr & " BPM") Writer.Close HRPrev = myhr End If 89

99 End If End Sub Sub mytimer_tick If AStreams.IsInitialized = True Then Else End If 'send request to device Dim Buffy() As Byte StrBuff01 = "ABP" & reqtype Buffy = StrBuff01.GetBytes("UTF8") AStreams.Write(Buffy) StrBuff01 = "" If reqtype = "C" Then ProgressDialogShow("Calibrating Device. Please Wait..") Else If reqtype = "B" Then End If ProgressDialogShow("Requesting BP. Please Wait..") Msgbox("You must connect first to the device before starting the monitoring process.","error!") mytimer.enabled = False End Sub Sub btnstartstop_click If btnstartstop.text = "Start" Then btnstartstop.text = "Stop" mytimer.enabled = True mylogger.enabled = False reqtype = "C" Else End If End Sub btnstartstop.text = "Start" mytimer.enabled = False mylogger.enabled = False Sub btninquirebp_click reqtype = "B" 90

100 End Sub Sub btncalib_click End Sub StartActivity("viewHistory") List of Materials Quantity Item Price per unit Total amount 1 IC socket - 40 PINS V Rechargable Battery 1 Watson s Digital Blood Pressure 2 LM324N Voltage Regulator 1 RT9163 IC N4148 Diode Capacitor (0.1µF) Capacitor (470 µf) Capacitor (22 µf) Capacitor (100 nf) Capacitor (33 pf) Resistor (100Ω) Resistor (330Ω) Resistor (1kΩ) Resistor (3kΩ) Resistor (22kΩ) Resistor (100kΩ) Resistor (500kΩ) Green LED Bluetooth Dongle PIC18F Pulse Oximeter Probe 2 Multi-turn Linear Potentiometer 1 Small Casing Big Casing Set of wires Total

101 APPENDIX E Blood Pressure Chart 92

102 APPENDIX F Heart Rate Chart 93