International Conference on Electrical Electronics and Communications-ICEEC-21st June 2014-ISBN-978-93-81693-66-03

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WEB SERVER NETWORK FOR ECG RECORDING AND BODY

TEMPERATURE MONITORING SYSTEM BASED ON ARM

MICROCONTROLLER

SHRUTHI G. B

1, NAVEEN H

2, PRIYA R SANKPA

3

1Ug, BNMIT,

2Asst Prof, MSEC,

3Asst Prof, BNMIT

Abstract: Recent development of Biomedical application like ECG recording and body temperature monitoring system for

time saving and low cost products are focused most . In this report we using a system based on web server network (WSN)

for recording ECG data and monitoring body temperature using ARM Microcontroller. The report describes continuous

recording of ECG signal on to web server and also displayed on on-board LCD display on MCU unit. It also describes Body

temperature monitoring system. Low voltage ECG signal from the electrode is Amplified by Instrumentation amplifier(INA)

and converted to digital values using ADC1298 . The acquired ECG signal are converted to specific format using ARM

MCU and recorded continuously in web server. The recorded ECG graph can be seen at any place using secured web

network.

Keywords- ECG,ARM MCU,ADC1298, INA ,LCD,WSN

I. INTRODUCTION

In recent years there has been increasing demands in

Biomedical area . To evaluate the performance of

cardiovascular system, continuous recording of

patient’s ECG is needed and also monitoring body

temperature of patient’s is required. A System which

has both ECG recording and Body temperature

monitoring interfaced with web server might help to

increase the comfort of patient and also it might

improve the leaving standard of the patient. The

detailed structure of project is given in Figure 1.

Figure 1: Structure of our project

There were many research which are carried on ECG

recording and increasing cardiovascular disease like

heart attack due to time and resource constraint

which motivated to carry out our work which give

precaution even better than the work which were

proposed in earlier research.

Most of the deaths due to heart attack are because of

less monitoring of patient’s who are at potential risk.

Wearable ECG device to record ECG data on to SD

card storage[1] inspired us to improvise it by using

web sever network to record ECG data.

The project aim is to reduce cost and to increase the

performance by using web server interface in place of

any other wireless device like Zigbee or Bluetooth.

.

A. Technical Background

Wearable ECG recording and Monitoring device

based on MSP430 MCU [1][2] was previous work

carried where amplified ECG data converted to

specific format by MSP430 to store in SD card.

Limitation of this work was unnecessary usage of

resource and time constraint.

In the research work of Wireless body area sensor

network [3] tiny wireless sensor network were placed

on the human body any vital sign can be monitored

by the user and personal. Limitation of this work is

limited range of wireless sensor network.

Our project uses resource efficient design and range is

also not limited as compared to WBAN research work

B.Proposed Solution

The simple solution is proposed in our project which

overcomes the limitation of the previous work.

The wearable ECG recording system to SD card is

extended to web server network where ECG data is

monitored on LCD display and also continuously

recorded into web server where time and resource are

efficiently utilized.

At remote place we can monitor the ECG data which

solves the range limitation of WBAN network. The

Top level block diagram of proposed work is given in

Figure 2

Our Project

Patient System Server system Doctor system

ECG Recorder Body temperature

Monitor

Web server network for ECG Recording and Body Temperature Monitoring System based on ARM Microcontroller

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Figure 2: Top level Block diagram

C. Organization of the Paper

Organization of the paper is as follows : System level

block diagram and detailed description about the

proposed solution are discussed in Section II ,

hardware and software implementation of our project

are given in Section III , results snapshots and test

trials are discussed in section IV , Conclusion and

future scope given in section V.

II. PROPOSED SOLUTION

The system-level block diagram of our project with

signal flow is as shown in figure 3

Figure 3 : System level block diagram

The hardware and software components used in our

design are ECG Electrodes and body temperature

sensor which are weak analog signals in mv, Theweak

signal is converted into strong signal by using

instrumentation amplifier (INA123). For processing

of data in Microcontroller unit, the analog signal

ouput from INA123 is converted to digital data using

instrumentation ADC IC i.e ADS1298.

Using microcontroller LPC1298 ARM 7 TDMI the

digital ECG data converted to specified format and

monitoring on LCD display and the same data is

processed into server system and the real time ECG

graph for three electrode and the body temperature of

patient is displayed. ECG data which is recorded into

system can be viewed by patient using there secured

ID and passwordprovided and also authenticated

doctor can view the details of the patients,ECG plot

and body temperature reading can be analyzed easily.

ECG signals are measured with button type ECG

electrode it uses AG/Agcl sensor element which has

best sensitivity and solid conductivity .Adhesive

hydrogel has very low impedance and is non irritating.

Body temperature signals are measured with

temperature sensor TMP36 it is very similar to LM35

temperature sensor.

The ECG signals which come from electrodes are

1mv peak to peak . An amplification is required for

suitable heart rate detection . Best approach is to use

differential amplifier like Instrumentation amplifier

INA123 . The device is operated at 2.7v. INA

provides fixed amplification of 5x for ECG signal.

The output of Instrumentation amplifier is analog

need to be made digital for processing of ECG data in

MCU .MSP430 has built in ADC but for ECG data,

instrumentation ADC (ADS1298) is

preferred.ADS1298 is operated at maximum of 3.2v

for digital data, it is an 8 channel low power, 24 bit

resolution delta sigma analog to digital converter, it

uses simultaneous sampling , it has onboard oscillator.

It has all the features required for biomedical

application like ECG recording. Digital ECG data is

sent through SPI bus to ARM7 MCU for

preprocessing.

ARM7 TDMI family of ultra low power

microcontroller consists of several devices featuring

different set of peripherals. The special feature of this

microcontroller that we are going to use are Op-amp,

built in LCD display, ADC, USB interface and

USART.

Sampling of ECG data has to be done , The amplified

ECG signal is given to the instrumentation ADC

(ADS1298) which output’s 24 bits of data per channel

in binary two complement format.A positive full scale

input produces an output code of 7FFFFFh and the

negative input produces an output code of 800000h.

LSB has a weight of Vref/(2^23 -1). The device has

only 17 and 19 bit resolution. The table 1 gives ideal

output code verses input signal [5]. The ADC in the

device offer data rates from 250SPS to 32kSPS.

Communication to the devise is by SPI interface.

Internal oscillator generates a 2.048MHz clock.

Electrode 2

Electrode 1

Electrode 3

ECG Electrode sensor

LM275

Body temperature Sensor

Microcontroller Unit

ADC

INA13

ECG

Acquisition

Unit

Server

system

Doctor

System

Patient

system

Web Unit

Web server network for ECG Recording and Body Temperature Monitoring System based on ARM Microcontroller

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Table 1: Ideal output code verses input signal

The sampled ECG signal contains some amount of

line frequency noise. This noise can be removed by

low pass filtering the signal. The filtered signal can be

output on display unit by the DAC of Microcontroller

unit (ARM) or it can be monitored on LCD display or

transmitted to PC using UART of ARM MCU. Here

we are monitoring the ECG signal on LCD Display

and also transmitted to PC using UART (USB Cable).

The ECG data is processed into server PC using USB

interface and stored in specific format and this format

is converted into web format using html code and the

ECG graph for three electrode and body temperature

data in Fahrenheit is displayed and this recorded data

can be viewed anywhere with secured username and

password by doctor and also by patient.

III. IMPLEMENTATION

A. Hardware Implementation

In our project we using three ECG lead electrodes for

ECG recorder and TMP36/LM35for body

temperature monitoring as shown in figure 4[7][2].

Figure 4: TMP36 and ECG Electrodes

The complete hardware schematic before digital

processing is as shown in the figure 5 below.

Figure 5 :Processing Hardware schematic

The ECG data and temperature data are first

amplified by an instrumentation amplifier and given

as input to the Instrumentation ADC (ADS1298) for

conversion to digital format and it is display on LCD

Display.The figure 6 gives the hardware schematic

for LCD Display module.

Figure 6 :LCD module Hardware Schematic

In this hardware implementation shown in figure 7 ,

The Amplified ECG electrode data from three

electrodes are separated and individually

preprocessed before driving this data into

Microcontroller unit (ARM 7).

Figure 7: Hardware schematic for USB Interface

Web server network for ECG Recording and Body Temperature Monitoring System based on ARM Microcontroller

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The individual Digital ECG Signal are driven into

Microcontroller unit using Serial port interface

(USB).The ECG data which are loaded are converted

to specific format by Microcontroller unit (LPC2148

ARM7 TDMI) and displayedonon- board LCD

Display.

Figure 8: Temperature sensor Hardware Schematic

The Figure 8 shows temperature sensor interface

before ADC conversion. From the figure,

LM35/TMP36 IC are used to read body temperature

to a certain level and this temperature data also need

to be converted to digital to display /store in Server

PC.

The Processed ECG data is recorded to the system

using UART interface from ARM 7 microcontroller

and the data are recorded into web server and also

body temperature are monitored continuously and it

is displayed on on-board LCD display of ARM7

microcontroller and the same temperature data are

displayed in web server.

Few of hardware related challenges was while

designing ADC, Crystal and few register were

interchanged. There was no proper ECG data

recorded. We also faced problem to interface MCU

with PC using USB port. Data to get on terminal

window was really challenging part in this project.

Figure 9: Finished MCU Unit

The figure 9 shows the completely finished MCU

unit withLCD Display .

B. Software Implementation

In our project Embedded C code for ARM

Microcontroller is implemented , mainly the software

code is used for getting digital data in specific format

from instrumentation ADC and this data are displayed

on LCD Display as well as using this code formatted

data is loaded into server system for further

processing

Software implementation involves two flow diagram

or flow chart one is to process ECG data in specific

format from ADC in ARM MCU ,second is to

monitor body temperature data and ECG data in

specific format on LCD display.

The Flowchart diagram for Recording ECG by MCU

into server PC is as shown in Figure 11.

Figure 11: Flowchart for recording ECG Data

The amplified ECG data has to be converted to

digital format so first ADC I/O is initialized .Check

for ADC data, if ECG data available, select 3

channels out of 8 channel and convert to specific

format;send the ECG data into PC using USB. Repeat

the process till reset is made low.

Web server network for ECG Recording and Body Temperature Monitoring System based on ARM Microcontroller

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The Flowchart diagram for ECG and Body

temperature monitoring is as shown in figure 12.

Analog Temperature data is converted to digital data

using ADC. One channel out of 8 channels is used for

temperature monitoring and converted to specific

format. The body temperature is sent to PC using

USB. Temperature reading is displayed in

Fahrenheit.

Figure 12: Flowchart for monitoring Body temperature

IV. RESULTS

A: Hardware result

The figure 13 showcomplete hardware to process the

ECG data on to web server and continuously

monitored on LCD display

Figure 13:Hardware Product

B: Software Result

After Processing of data into specified format by

MCU, simulated results from Eclipse for ECG data

are given in the figure 14.

Figure 14: Eclipse Database Acquired ECG result

C: Web result

The simulated data from CCS studio is converted to

HTML data for plotting ECG graph on Web server.

Temperature data are continuously monitored in web

server. Figure 15 gives login page where we enter

unique username and password. Figure 16 shows

ECG graph on web server which runs in real time

Figure 15: Web server login page

Figure 16: Real ECGgraphin web server

D: Field Trials

Field trial was conducted and compared with existing

ECG device with ECG graph which is recorded in the

Web server network for ECG Recording and Body Temperature Monitoring System based on ARM Microcontroller

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web server for three electrodes, Figure 19 shows the

ECG setup and ECG graph of an Existing system.

Figure 19: ECG setup andGraph of an Existing system

ECG graph for proposed system taken for three electrodes are

shown in figure 20.

Figure 20:ECG Graph for Proposed system

CONCLUSIONS

Our project web server network for ECG recording

and body temperature monitoring system for people

suffering from cardiac disorder who wish to lead an

active lifestyle. In this report ECG recording into SD

card and into web server network is present. It also

present monitoring of body temperature. We have got

successful recording of ECG data and body

temperature is precisely measured.

Only few trial test are done on few people. Actual

test on patient is not explored. This project has wide

scope in small scale industry because of its low cost,

easy access by many people at the same time.

We have considered three electrode in our design,

five electrode design will be explored in future

implementation. Real time access is available only at

the server system where hardware connected.

We will expand our web design for accessing real

time ECG data by doctor system who is at far

distance.

ACKNOWLEDGMENTS

We like to thank our management for giving

opportunity to participate in TI design contest, We

like to thank HOD ,TCEDept BNMIT for her

constant support in completing this project. We like

to thank Dr.Ravish.

H for giving input on medical application and other

medical related information and also for providing

lab facilities to test over project. We like to thank

Santosh .B.S for his support in building web part of

project.

Our sincere thanks to external mentor Naveen. H for

his constant support in making documentation and

building this project.

REFERENCES

[1]. Asifiqbal Thakor, Prof. Rahul Kher,and Prof. Dipak Patel,

“Wearable ECG Recording and Monitoring System based

on MSP430 Microcontroller”,International Journal of Computer Science and Telecommunications October 2012.

[2]. J. Mühlsteff O. Such, R. Schmidt, M. Perkuhn, H. Reiter, J. Lauter, J. Thijs, G. Müsch, M. Harris. “Wearable approach

for continuous ECG- and Activity Patient Monitoring”.

Proceedings of the 26th Annual International Conference of the IEEE EMBSSan Francisco, CA, USA., September 1-

5,2004.

[3]. J. W. Zheng, Z. B. Zhang, T. H. Wu, Y. Zhang. “A

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[4]. Yoshio Okada, Tsuyoshi Yi YOTO, Taka-aki Suzuki, Satoshi Sakuragawa Industrial Research Institute of

Shizuoka prefecture Shizuoka, Japan ,Toshifumi Sugiura Research Institute of Electronics, Shizuoka University

Shizuoka, Japan, “Development of a Wearable ECG

Recorder for Measuring Daily Stress”. International conference on Information science and application 21-23

April 2010.

[5]. Aleksandra Milenkovic´ *, Chris Otto, Emil Jovanov,”

Wireless sensor networks for personal health monitoring:

Issues and an implementation, March 2006

[6]. Chris Otto, Aleksandar Milenković, Corey Sanders, Emil

Jovanov,” System architecture of a wireless body area sensor network for ubiquitous health monitoring” Jan 2006.

[7]. Tang Yawei,Jiang Kai*,Fu Xiuquan,Li Dingli,”Low Power

dual-core Holter Systerm Based on MSP430 and ARM7,2007

[8]. J.L.Urrusti and W.J.Tompkins, “Performance evaluation of an ECG QRS complex detection algorithm” Proc. Annual

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Web server network for ECG Recording and Body Temperature Monitoring System based on ARM Microcontroller

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APPENDIX A

Final ECG PCB design