Non-invasive Glucose Monitor

Gluco-Medes Design Report 1

March 20, 2015

Final Design Report

Non-Invasive Glucose Monitor

Gluco-Medes

Charlie Aylward

Jonah Clinard

Amanda Toan

Travis Stuever


Table of Contents

Introduction……………………………………………………………………….……..3 Project Overview……………………………………………………………….....3

Clients…………………………………………………………………………......3

Stakeholders……………………………………………………………….……...4

Framed Insights and Opportunities…………………………………………….....4

Goals and Objectives……………………………………………………………..6

Outcomes and Deliverables……………………….……………………………...7

Team Mission and Objectives…………………………………………………....7

Team Membership and Roles…………………………………………….……....8

Planning Information……………………………………………………….…….8

Related Work……………………………………………………………………….…...9 Formal Product Definition……………………………………………………………..12

Introduction……………………………………………………………………....12

Marketing Requirements………………………………………………………....13

Engineering Requirements……………………………………………………….14

Constraints………………………………………………………………………..14

Criteria…………………………………………………………………………....15

The User Experience…………………………………………………….…….………..16

Overview………………………………………………………………………....17

Personas…………………………………………………………………………..17

Design and Justification………………………………………………………………...18

Overview of Team Process…………………………………………………….....18

System Architecture……………………………………………………………....19

Hardware Design..…………….…………………………………………………..19

Software Architecture…………………………………………….……………….26

Mechanical Design……………………………………………….……………….27

Test Plan……………………………………………………………….………………....27

Appendices……………………………………………………………………………….30

Bill of Materials………………………………….………….……....…………....31

Gantt Chart…….………………………………………….…………….….…….32

Circuit Diagrams…………………………………………………….…………...33

Final Test Plan………………………………………………………………..….36


Introduction Project Overview

The Gluco-Medes team was formed in order to develop a non-invasive glucose monitoring

device. The team will be working with New Vision Telemedicine (NVT) as well as Innovative

Concepts to complete this project. The most important goal of the project is to create a device

that will measure blood glucose levels with some degree of accuracy. The other major goal of the

project is for the device to be simple enough for easy accessibility of individuals who may have

disabilities. After measuring the glucose levels, the device should also be able to display the

results of the test onto an android device with an android based application loaded onto it. In

short, the device aims to become a new and reliable solution to the invasive ways of measuring

blood glucose levels.

Clients

The clients of the project are Dr. Ahmad Nooristani and Paden Hughes of New Vision

Telemedicine and Lonny Rollins of Innovative Concepts. New Vision Telemedicine is a

company that aims to ensure quality health care for those in need by providing telehealth

products that will allow for easier communication between families, patients, and companies

with medical consultations. The company is run by Dr. Ahmad Nooristani, who is a practicing

hospitalist and previous chair of the Department of Medicine at his local hospital. Innovative

Concepts is acting as the IT consultant for the project, with Lonny Rollins, the CEO, being the

main consultant. The final product of this project, if finished, will be given to Dr. Nooristani of

NVT to use as he deems fit. Otherwise, it will most likely be a project that Innovative Concepts

will take over.


Stakeholders

There are many stakeholders involved in this project, including the clients of the project, people

with diabetes, as well as people affected by those with diabetes—family members of people with

diabetes. The main clients of the project are Dr. Nooristani and Paden Hughes, the

representatives of New Vision Telemedicine, the company whom this team is collaborating with

for this project. The other client whom the team will be working with is Lonny Rollins, the CEO

of Innovative Concepts. These two clients will be most interested in the success of the project as

they are the main investors of the project and have the most to lose. Aside from the obvious

stakeholders—the clients—however, there are also two other groups to consider. These two

groups are people with diabetes and family or friends of people with diabetes. The success of this

project will have a major impact on the lives of those suffering from diabetes as it will allow

them to measure their glucose levels without having to draw blood. A reliable non-invasive

glucose monitor can also potentially lower the medical costs of families with diabetic members.

Friends and family will also no longer have to watch their loved ones prick their fingers several

times a day just to measure their glucose levels. To sum it up, many people will be affected by

the success of this project, including the members of this team, making the success of this project

all the more desired.

Framed Insights and Opportunities

The initial meeting between the team and the clients focused on the specifications expected of

the device and the possible design solutions for the device. One possible design suggested by

Lonny Rollins—the acting IT consultant of the project—for the device included the use of light

sensors to measure the percentage of the glucose levels within the body. This design utilizes

specific frequencies of light chosen within a range of wavelengths in order to calculate and


determine the glucose level of an individual. Other designs were also briefly mentioned, such as

measuring glucose levels through saliva or tears. However, Lonny expressed the preferred choice

of using the light sensor for the project; though it should be noted that alternatives were deemed

acceptable if proven to be better or easier to work with. The location at which the device is to

measure the glucose levels was also discussed during the meeting. Several different parts of the

body were suggested. These suggestions included measuring at the earlobe, the area between the

pointer finger and thumb, or the wrist. The client’s preferred choice of location was the wrist.

However, the wrist was decided to be the location that would most likely cause the most trouble

as the bone would have to be taken into account when trying to measure the reflections of light.

Therefore, it was suggested that the team start at a much easier location for the initial device

design such as the area between the pointer finger and thumb or the earlobe. These locations are

ideal for testing as they are areas that do not contain bone, which is the main concern with the

wrist based design. Once the device starts working on those areas with reasonable accuracy, it

can then be slowly moved towards the client’s desired wrist area. The initial design of the clients

has the device simply measure the individual’s glucose level and then have it display directly

onto an android based mobile application. This particular aspect of the project, however, can be

expanded on, if time permits, to being able to possibly transmit the data to Dr. Nooristani

directly or into a database of New Vision Telemedicine’s. Ultimately, the most vital part of this

project that was agreed upon was accuracy. Being able to measure the glucose levels of

individuals accurately is of the utmost importance. An aesthetically pleasing device, although

would be nice to have, is the least important aspect of the overall goal of the project. Individuals

with diabetes who will need to use the device several times a day need to be able to rely on the

device and trust that it will give them accurate readings. An inaccurate device will not only be


useless for the company and its potential users but will also mean that the team essentially

wasted all their time into producing a device that does not work. In conclusion, an accurate

device will not only help New Vision Telemedicine and people suffering from diabetes but will

also prove to have been a project worth all the time and effort put into it by the team itself.

Goals and Objectives

The following list highlights the goals and objectives of the project.

● The product should be affordable for average consumers/patients.

● The device should be simple to use.

● The device must be reliable

● The device must be portable.

● The final product must be aesthetic/sleek.

● Using the device must be 100% safe.

● The device will feature USB data transfer.

● Results will be displayed on mobile devices (Android).

● The device will work with an Android application.

● Accuracy needs to be within 80% of a typical venipuncture test.

● The device will use 1500 - 1700 nm wavelength light for sugar reflection.

● The device will operate in room temperature environment (20-26C).

Outcomes and Deliverables

The final result of this project should be a working non-invasive glucose monitor. The device

should be able to accurately measure the blood glucose level of the user with results comparable

to a traditional method, such as finger pricking. Results of the blood glucose measurement


should then be displayed on an android device loaded with an android based mobile application.

Upon completion of this project, the team hopes to leave behind a reliable and working device.

The team will also aim to leave behind not only a working device, but also an aesthetically

pleasing encasing of the device, though it should be noted that this is not a major priority of the

project. In conclusion, even if not aesthetically pleasing, a working and accurate device will be

considered a finished product for this project.

Team Mission and Objectives

The following subsections highlight the team’s mission and objectives.

Team Mission

Our mission is to provide easier means of communication between doctors and their patients

through the use of medical technologies.

Team Objectives

● To better the lives of others

● To successfully collaborate between team members and our client

● To improve doctor patient communication

● To provide a working product

● To meet the needs of our client

● To create lifelong bonds between team members

● To further develop the understanding behind telemedicine

● To gain experience through real life application

● To apply skills and concepts we have learned in our CPE studies


Team Membership and Roles

The members of Gluco-Medes are: Jonah Clinard, Amanda Toan, Travis Stuever, and Charlie

Aylward. The following list shows the team roles as well as the assigned roles of the team

members.

Project Manager and Liaison - Charlie Aylward

Procurement and Financial Officer - Jonah Clinard

System Architect - Amanda Toan, Travis Stuever

Hardware Architect - Jonah Clinard, Travis Stuever

Software Architect - Charlie Aylward, Amanda Toan

Hardware Designer - Travis Stuever

Software Designer - Charlie Aylward, Jonah Clinard

System Interface - Travis Stuever, Amanda Toan

Development Tools Specialist - All team members

Product Verification - All team members

Product Reliability and Serviceability - All team members

Planning Information

While planning this device, there are various constraints and challenges to keep in mind. One

major constraint to this project will definitely be time, having only around six months to

complete such an ambitious project. Another challenge is the development period; as the project

currently has no known working and approved device, the time for developing a design will

definitely be longer than other projects. Due to the technology still being in the early infant

stages, this project will potentially present many unforeseeable problems during the whole

duration of the project. As the team consists of all computer engineers with little to no


background of such medical devices/technology, a large bulk of the planning/development stage

will consist of heavy research on the type of sensors to use. The client also did not specify a

specific design they desired for the project, leaving the design process much more open-ended

and up to the members of the team. Seeing as this technology is still so new to the market, there

is still much to be learned by the team members as well as plenty of planning.

Related Work

Krishnamurthy, Gaurav. “Non-Invasive Measurement of Blood Glucose Levels Using

GlucoTrack: Interview with CEO Avner Gal.” MedGadget, 13 Oct.

2013. Web. 9 Oct. 2014.

This article talks about an Israeli company who has developed a

non-invasive glucose monitor. The device clips to the user’s ear in

order to measure their glucose levels, which is then displayed onto

the screen of a device. The ear lobe is chosen because it’s a

convenient location that doesn’t interfere with activities. It also

contains a large number of capillary vessels and blood flows relatively slowly in the ear lobe. It’s

size is also relatively stable in adults. The device uses ultrasonic, electromagnetic and thermal

technology with multi-sensors.

Ahmad, Masab, Awais Kamboh, and Ahmed Khan. “Non-invasive blood glucose monitoring

using near-infrared spectroscopy.” EDN Network. 16 Oct. 2013. Web. 9 Oct. 2014. This article

talks about using near infrared spectroscopy to determine glucose levels. This device measures

glucose levels on the ear lobe. The thickness of the ear lobe is also measured to calibrate it. They

choose a wavelength of 1550nm for the glucose signals due to its high signal-to-noise ratio.


Photodiode signals are fed into an amplifier to amplify the NIR

signals. The correlation coefficient between their device and a

reference glucometer is 0.85. The reading is displayed on an LCD

and an android phone through bluetooth.

"GlucoWise™." : Meet the New Non-invasive Glucose Monitor

That Helps You Take Control of Your Life. N.p., n.d. Web. 10

Oct. 2014.

This device is a glucose monitor that takes its readings from the skin

between the thumb and forefinger and also from the earlobe

interchangeably. This device uses radio waves at the high frequency

of 65 GHz and uses these waves to send through the skin to a sensor

on the opposite side of the hand or earlobe. The special thing this

company says its product does is temporarily make the skin of the analyzed area transparent

ensuring consistent readings across all individuals. The actual specifics of what calculations are

done with this product are not given on the website but the product is scheduled to make its

market appearance in late 2016.

Honor Whiteman. “New breathalyzer ‘monitors blood glucose’ in diabetics.” 12 Nov. 2013.

Web. 15 Oct. 2014.

This article is about a breathalyzer based approach to glucose

monitoring. Ronnie Priefer, who is a researcher at Western New

England University in Massachusetts, has discovered a way to

measure one’s glucose levels through the acetone levels in one’s


breath. The device incorporates a piece of film that has different nanometer thick levels of

polymers on it. The acetone levels from one’s breath join with the polymers and in turn cause a

reaction with the film. Currently the device is about the size of a book, which Priefer is working

on changing, he expects the device to enter testing procedures for accuracy in early 2015.

Scott, Mark. "Novartis Joins With Google to Develop Contact Lens That Monitors Blood

Sugar." The New York Times. The New York Times, 15 July

2014. Web. 10 Oct. 2014.

This device is yet another that is not yet on the market but still

within its development cycle. This device will use a so called

smart contact lens that has built in sensors and software that

will provide blood glucose level monitoring as part of one its offerings. This device of course

will have to pair to an application in order to send out data taken while on the eye. Beyond what

can obviously be stated not much is known on how the lens will calculate the glucose levels.

This product holds a lot of promise however as it is a joint venture with Google and Novartis,

wherein Google can provide all the technology Novartis needs in order to make this a reality.

"Grove Instruments - Grove Technology." Grove Instruments - Grove Technology. N.p., n.d.

Web. 10 Oct. 2014.

This device has had a lot of grants awarded to its development,

about 7.8 million according to its website, and is slated to hit the

market in 2016. The actual specifics of this product are not

documented at all on Grove's website but what they do say is that

they have a technology to nullify the background tissue and water content of the analyzed region,


and sense glucose levels in the vascular space. What exactly this means is anyone's guess but it

has at the very least created a viable product for this company. Their current test results show

that they have achieved readings as accurate as 88% and higher compared to conventional

means.

The related works which we found most applicable to our design is the prototype glucose

sensor created by Masab Ahmad, Awais Kamboh and Ahmed Khan, published on EDN Network.

This design had the most (while still limited) information regarding the hardware and software

architecture to base our design off of. The parts used in this device complied with our design

constraints of created a low-budget device.

Formal Product Definition

Introduction

Moska, our formal product name, is a new non-invasive glucose monitor that aims to replace the

traditional finger-pricking method through the use of light and light sensors. The simple one

button design of the product allows just about anyone, regardless of age, to use it with ease. With

the push of a button, the device will accurately measure the glucose level of the user. The results

of which will then be conveniently displayed onto an android device for easy monitoring. Listed

below are the requirements as well as constraints of the device.

Objectives

● The product should be affordable for average consumers/patients.




● The final product must be aesthetic/sleek.


● Using the device must be 100% safe.

● The device will feature USB data transfer.

● Results will be displayed on mobile devices (Android).

● The device will work with an Android application.

● Accuracy needs to be within 80% of a typical venipuncture test.

● The device will use 1500 - 1700 nm wavelength light for sugar reflection.

● The device will operate in room temperature environment (20-26C).

Marketing Requirements

● The product should be affordable for average consumers/patients



● The readings must be accurate.


● The final product must be aesthetic/sleek

● Using the device must be %100 safe

● Environmentally Friendly

● Modular

● Device will have universal accessibility (disabled patients will be able to use)

Engineering Requirements

● The device will be USB powered (5V)

● The device will feature Bluetooth/USB data transfer

● Accuracy needs to be within 85% of a typical venipuncture test

● The device will use 1500-1700 nm wavelength light for sugar absorption


● The device will operate in room temperature environment (20-26C)

● Have replaceable components

● More affordable than comparable monitoring techniques

● No initial calibration required

● Earpiece must weigh less than 2.5 oz

● RoHs compliant

Constraints

● The device must engineer

● The device must be simplistic in its nature

● The device must be accurate

● The device must be noninvasive

● Results will be displayed on mobile devices (Android)

● The device will work with an Android application

● The device must be completely safe to use

● The device must be affordable

● The final product must be aesthetic/sleek

Criteria

In order to effectively meet the constraints and engineering requirements, some standards are

needed to help with the decision making process. An example of this would be the size of the

device. The clients wish for the device to be small, however, the size of the device will

ultimately depend on several different aspects of the design. Things such as the end user and the

necessary technology needed for the device will need to be taken into consideration when

deciding on and designing the size of the product. The device will need to be large enough to


house a microcontroller, a sensor, and several LEDs. However, the device will also need to be

able to clamp comfortably onto the user’s earlobe. This means that the device should be small

enough where it will not feel too heavy on the user’s earlobe. The device also needs to be

affordable and accurate. These two requirements, in particular, are dependent on each other as a

cheaper part will most likely be less accurate than a more expensive part. Therefore, in order to

meet the criterion of being affordable, some accuracy may be lost. However, since a certain

percentage of accuracy is needed, the part will likely still be a little pricey. Careful thought will

be needed in order to find the cheapest point at which the device will still meet the required

accuracy. All of the previous standards were considered during the selection process. Table 1

shows the highlights of the decision making process to meet the criteria and requirements of the

device.

Table 1. Description of decision making process to meet product requirements

Requirement Criteria Decision

Size of device The device must be small The device must be large

enough to house the

microcontroller and the

sensors, but small enough to fit

on the users ear

Affordability of device The device must be affordable The average cost of devices

using invasive technology is

annually around $1200 we

consider any device that is

under this cost a success

Accuracy of device The device must be accurate Glucose levels of a human can

fluctuate within a matter of

minutes, after discussing with

our client we consider anything

that can report glucose levels

within 80% of their true values

to be a success

Accessibility of device The device should be usable Part of the accessibility of a


and accessible to everybody device depends on factors such

as the size and cost of the

device. In addition to these

factors we also must consider

the audience that is using the

device. Since some of the

device users may be elderly,

the device needs to be light

(weight) enough for their use.

The User Experience

Overview

A typical user of the non-invasive glucose monitor could be of any age or ethnicity and would

most likely have had prior experience with other invasive devices. It could be presumed that

these types of people are fed up with the traditional invasive methods of glucose monitoring and

would be open to try any non-invasive solution.

Personas

A person who would use this product could be of any age, therefore, this product must be simple

enough for young as well as old people to use. Users of this product are also not limited to just

one part of the world, as anyone could have the need to monitor their blood sugar levels.

Therefore, the simplicity of the design will be necessary so that the device can be used all over

the world by people of any age regardless of whether or not they live in the U.S. or speak

english. The main concerns for the users of this device will be whether or not the device is

accurate and if they will be able to discontinue the invasive methods of glucose measurement.

A specific example of an individual who may who this device is an elderly diabetic who

lives alone. This individual would want a product which does not weigh a lot so that it may not

damage their body, and our monitor would fit this criteria perfectly as we have put a limit on

how much our device can weigh. Because this individual is old in age they would not want a


product that requires them to do complicated steps so that it may work, and in this way our

simple one button setup would be perfect for this individual. Lastly this individual probably

would not have a lot of money, maybe due to the fact that they can no longer work as much as

they used to or even the fact that they are retired. With this low income our device would look

very nice to this individual because we will have a lower price than traditional methods and also

lower in price than comparable non-invasive monitors.

Use Cases

● Diabetics - This person will utilize the device to check their own blood sugar levels. This

is necessary for them to monitor their glucose levels to avoid dropping below or rising

above the healthy range.

● Doctors - This person will use the device with their patients to monitor the patient's

glucose levels. Doctors will be able to use the device for diagnosis of diabetes in patients

that are potentially at risk.

● Sales Rep - This person will promote the finished product to patients and doctors who fall

under the target audience. As the device strives to change the industry, the sales rep may

sway current medical practices to use the newer technology.

Design and Justification

Overview of Team Process

The approach taken to this project involved equal input from all team members to brainstorm

initial concepts and produce our design plan. The initial meetings, which included the client

(NVT), established a basis to build ideas from. At the client meetings, the product constraints

were discussed in order to ensure the end result matched the client’s requirements. Once the team


and the client reached an agreement with a feasible product and design, the team was able to

begin brainstorming implementations. During team meetings, goals were established with

deadlines to be met in order to make the planning process fluid and optimize productivity. Most

of the goals involved determining the specifications and parts required for the product to function

as required. Team members were expected to come to each meeting with a follow up on research

topics discussed at the prior meeting, as well as possible design ideas to be discussed with the

whole team. By the end of this process of elimination, the team reached a final design plan and

were ready to begin the implementation process.

System Architecture

Figure 1. Black Box diagram for non-invasive monitor

The architecture presented above in Figure 1 is a low level black box diagram of how each

separate component will coordinate and transmit data to the other components. Starting with the

earlobe device, it can be seen that this is where all the sensors will be located as well as receive

and transmit data. The LEDs will transmit a certain light wavelength in a certain order and the

light sensor will receive this data and send it on to the logic unit for processing. The same

process can be said for the earlobe thickness sensor which will, in some way, find out the

thickness of the ear and transmit the data. Moving on to the logic unit, this component will


regulate power for the sensors in the earlobe device if needed, and perform the calculations for

finding the glucose level. Lastly, the android device will provide power to the other two devices,

in addition to displaying the results of the glucose calculation for a user to see. These are the

only three components used in the glucose sensor.

Hardware Design

After discussing our ideas as a group, as well as doing some research about the proposed ideas,

we decided that the light sensors seemed to be what works best for non-invasive glucose

monitoring. It was also the method with the most available resources on the web, which is

definitely helpful for such a new type of technology. Our research also found that the earlobe

seemed to be the ideal location to measure blood glucose since the size of an earlobe doesn't vary

much between individuals and there would be little to no interference when shining a light

through it. This was the main reason for the elimination of the wrist, as it would be difficult to

work around the bone. Saliva and tears were also voted out since they didn't seem to have as

much resources available as compared to measuring at the earlobe. A specific microcontroller

has not been decided on for the final product, however, the Arduino will likely be chosen for use

during the testing/prototype stage. The concept fan in Figure 2 on the following page shows the

possible ideas for our chosen method of glucose monitoring.


Figure 2. Concept generation fan

Measuring Locations/Methods Sensors Computation Power

Webbing between index finger and thumb Light sensors (IR, LED, etc) Arduino USB

Wrist Chemical reaction Android Battery

Earlobe Thermal Microcontroller

Saliva Electromagnetic

Tears Sonar

Data Transfer Earlobe Width Measurement

Bluetooth Clamp

USB Sensor

WiFi Light


Table 2. Decision matrix for earlobe width sensor

Earlobe Width via

Sonar

Earlobe Width via displacement

sensor

Earlobe Width via

IR

Accuracy 0.60 7 9 7

Cost 0.10 5 5 5

Size 0.15 5 5 8

Range 0.15 8 8 8

Score 6.65 7.85 7.1

The above scores in Table 2 reflect the preferential device to be used for the measurement of

earlobe width. The three options to consider: width measurement via sonar (using sound

reflection), a strain gauge(displacement sensor), and via infrared light. This depends on the

availability of the sensor itself. For instance, if it is harder for to acquire a sensor using sonar,

then the next best option would be used in place of it. The size of the sensor isn’t a heavy weight

due to the fact that the device being placed on the user’s ear is already fairly large. Accuracy is

the primary concern, and thus holds the heaviest weighting. All three sensors would provide an

acceptable level of accuracy, therefore the other choices will determine the choice of the actual

sensor. At the moment we are currently leaning more toward using IR light to measure the width

of the ear, though we are looking more into using a strain gauge for the measurement.

Table 3. Decision matrix for microcontroller

Weighting Arduino IOIO-OTG

Cost 0.1 8 8

Size 0.2 5 5

Ease of Use 0.1 7 7


Speed 0.1 6 6

Power 0.5 10 0

Score 8.1 3.1

The above scores in Table 3 reflect the device being used for processing the data obtained from

the sensors. The weighting column reflects the relative importance (greater value is more

important) to our design. The weighting is broken across several different categories, the ease of

use, cost and speed of the device all received an equal weighting. The cost of the device is based

upon the idea that we expect the cost of the microcontroller to be one of the greater factors in our

device. The ease of use factor is strictly for the developers consideration, therefore both

microcontrollers received an equal score. The speed of the device comes down to the fact that all

it needs to do is read and transmit serial data to an android device, this allows the android device

to handle some of the processing. The size of the device is going to allow more convenience in

the accessibility and portability of the device. The power category is a consideration to how the

microcontroller will receive power, ultimately we arrived at the arduino due to the fact that it

could be powered over usb, whereas the IOIO couldn’t.

Table 4. Decision matrix sensor placement

Weighting Ear Wrist Thumb and

Forefinger

Webbing

Consistent Size 0.25 8 5 8

Location 0.25 7 8 5


Blood Flow 0.25 10 10 10

Density 0.25 9 3 9

Score 8.5 6.5 8

The above scores in Table 4 represent the decision for where the devices sensor should be placed

upon the human body. The weighting was broken equally across the four categories: consistent

size, location, blood flow, and density of skin. The options for placement were upon the users

earlobe, wrist, or between the skin webbing located between the thumb and forefinger.

Ultimately the decision resulted with taking the measurement on the users ear. There is no bone

to pass through, making the density score high, the blood flow is good due to many capillaries in

the ear lobe. The location of the earlobe is somewhat convenient for the user, and the size of the

earlobe is fairly consistent across humans. Unfortunately this might limit users with body

modifications such as earrings or gauged ear-lobes to not use our device, we are seeking ways

around this.

Table 5. Decision matrix for device power

Weighting Batteries Phone

Size 0.25 5 5

Environmental 0.25 3 7

Convenience 0.25 3 8


Cost 0.25 3 1

Score 3.5 5.25

The above scores for Table 5 reflect the decision process on how our device will be powered.

The weighting for each of the above four categories is equal because we felt that the size,

environmental impact, convenience and cost were all important for deciding how our device

would be powered. In terms of size a phone and battery pack are very comparable in size, but

they are still large items, so the score there reflects this. Batteries are thrown out as soon as they

are used up while a phone can be recharged so the phone wins the environmental aspect. Almost

everyone nowadays has a phone in their pocket, but who has batteries on their person, probably

no one so the phone wins this category also. Lastly the initial cost of a phone is high while

batteries are comparably cheap so batteries score higher than the phone on this. Adding up all the

scores it is clear in Table 5 that the phone was the choice for powering the device.

Figure 3 provides a very general data flow diagram for the device. As the diagram shows, the

fundamental operation of the device will be contained in six different steps. Initially, the user

will place the device on their ear, this will help ensure that the device can properly calibrate

while it powers on. After this the device will acquire the data reported by the sensor. This data

will then be processed and sent to the android device. Once the data has been received by the

android device, it will display the information to the user.


Figure 3. Data flow diagram

Software Architecture

Figure 4 represents the software data flow of the device. After the device is powered on, it will

wait for a button press, which acts as a signal from the user to let the device know that data is

ready to be transmitted. After the button is pressed, the user’s earlobe width and blood oxygen

levels will be measured. Using the earlobe width and blood oxygen levels will allow the device

to know if there is an adequate amount of blood in the particular position that the sensor is

placed. Once these levels are received, the glucose reading will be taken and then used to

calculate the glucose level of the user. The final stage will then be to display the results through

the android device.

Figure 4. State diagram for software data flow


Mechanical Design

At this point in the development process, our team has not yet decided what the casing will look

like or even what materials to use when building it. We do believe that some part of the casing

will be made using a 3D printer, but beyond that, we have not yet considered anything further. At

some point in the future, when we have created a working prototype, we will then design the

casing to fit what we have found works.

Test Plan

The component that the team will be most concerned with during the testing process involves the

LEDs. The LEDs are essentially the main component in the device as they are what will be used

to measure the glucose levels as well as possibly the width of the earlobe. Theoretically, the

LEDs within the range of 1500-1700 nm should all give a considerable amount of accuracy, as

research has stated that the wavelength to measure blood sugar should be around 1600 nm. So

the main concern would be to find the LED with the best accuracy. The testing plan for the LEDs

is to order several LEDs within the range of 1500-1700 nm and then comparing the results

against one another to see which will give the best reading. The level of accuracy of the LEDs

will be determined by testing the readings against a typical finger-prick glucose test kit.


Gantt Chart

Figure 5. Gantt chart for project timeline

The above Gantt chart in Figure 5, shows the rough outline of the schedule for the project. The

chart also shows which team members are responsible for which part of the project. As shown in

the chart, many things during the design process of the project are dependent on one another.

Therefore, it is very important that each team member will complete their designated tasks on

time. Once the initial alpha prototype is done, however, the final testing stages can then be done

as a team.


Budget Request and Justification

Most of the budget for this project will go towards the purchasing of the LEDs used to for the

calculation of glucose levels. The LEDs that will be used for the device are non-standard LEDs.

Due to the fact that they are non-standard LEDs, the pricing of the LEDs were found to be very

expensive. However, since the device will only work with LEDs in those ranges, the team has no

other choice but to purchase these expensive LEDs. Beyond the cost of the LEDs, the rest of the

components should be relatively cheap in comparison to the LEDs. Although the goal of the

project is to have the device be as low cost as possible, there is no guarantee the device will stay

within budget, especially since there is still no definite list of the materials needed for the device.

Bill of Materials

Table 6. Project bill of materials

Item Name Part # Supplier Name Quantity Price Each Extended Price Total

Vials 10mm N/A Cal Poly Corp. 10 $0.75 $7.50


12-bit ADC ADS1015 Adafruit 1 $9.95 $9.95

Photodiode MTPD1346-150 Marktech 1 $26.66 $26.66

Photodiode FGA10 ThorLabs 1 $158.10 $158.10


1550nm LED LED1550E ThorLabs 2 $17.95 $35.90

Cuvette 5mm 1-G-5 Starna Cells 1 $45.00 $45.00

$343.11


References

Ahmad, Masab, Awais Kamboh, and Ahmed Khan. “Non-invasive blood glucose monitoring

using near-infrared spectroscopy.” EDN Network. 16 Oct. 2013. Web. 9 Oct. 2014.

"GlucoWise™." : Meet the New Non-invasive Glucose Monitor That Helps You Take Control of

Your Life. N.p., n.d. Web. 10 Oct. 2014.

"Grove Instruments - Grove Technology." Grove Instruments - Grove Technology. N.p., n.d.

Web. 10 Oct. 2014.

Honor Whiteman. “New breathalyzer ‘monitors blood glucose’ in diabetics.” 12 Nov. 2013.

Web. 15 Oct. 2014.

Krishnamurthy, Gaurav. “Non-Invasive Measurement of Blood Glucose Levels Using

GlucoTrack: Interview with CEO Avner Gal.” MedGadget, 13 Oct. 2013. Web. 9 Oct.

2014.

Scott, Mark. "Novartis Joins With Google to Develop Contact Lens That Monitors Blood Sugar."

The New York Times. The New York Times, 15 July 2014. Web. 10 Oct. 2014.

Appendices

Bill of Materials

Gantt Chart

Circuit Diagrams, Layouts, CAD Drawings, etc.

Final Test Plan Documentation


Bill of Materials

Hardware Listing:

Item Name Part # Supplier Name Quantity Price Each Extended Price



12-bit ADC ADS1015 Adafruit 1 $9.95 $9.95

Photodiode MTPD1346-150 Marktech 1 $26.66 $26.66



1550nm LED LED1550E ThorLabs 2 $17.95 $35.90

Cuvette 5mm 1-G-5 Starna Cells 1 $45.00 $45.00

$343.11


Gantt Chart

The following is a gantt chart outlining the timeline and workflow

of our project


Circuit Diagrams and Layouts

System Schematic of the Device

Block Diagram of the Entire System

System State Diagram


Data Flow Diagram

Concept Generation Fan Diagram


Non-Invasive Glucose Monitor

High Level Functional Verification Test Plan

Version 2

March 20, 2015

Prepared for

New Vision Telemedicine

Prepared By

Gluco-Medes

Charlie Aylward ([email protected]), Jonah Clinard

([email protected]), Travis Stuever ([email protected])

Introduction

This is the non-invasive glucose monitor high level test plan prepared by the Cal Poly capstone

team Gluco-Medes for New Vision Telemedicine. This document describes the procedures taken in the

testing phase of the glucose monitor.

Document Control Information

Author / Owner

Travis Stuever - Design/Application Specialist- [email protected]

Jonah Clinard - Application/Hardware Specialist - [email protected]

mailto:[email protected]


Charlie Aylward - Implementation Specialist and Team Leader - [email protected]

Approvers

The following people provide the approval of this document:

Name Function Approval Date

Dr. Nooristani Client

John Oliver Class Leader

Reviewers

The following people provide the review comments to this document:

Name Function Mandatory/Optional

John Oliver Class Leader Mandatory

Dr. Nooristani Client Mandatory

Summary of Changes

The Author/Owner of this document is authorized to make the following types of changes to the

document (identified in the change history) without requiring the document re-approval:

Editorial, formatting, and spelling

Clarification

Document structure

Note: Any other changes may require re-review and re-approval.


To request a change to this document, contact it’s Author/Owner.

Changes to this document are summarized chronologically in the following table.

Version Number Date Summary of Changes Editor

1.0 1-28-2015 Initial Write Up Glucomedes Team

1.1 1-31-2015 Cont.Initial Write Up Glucomedes Team

1.2 2-4-2015 Cont. Initial Write

Up

Glucomedes Team

1.3 2-9-2015 Cont. Initial Write

Up

Glucomedes Team

2.0 3-19-2015 Final Revision Glucomedes Team

Supporting Documents

The following are the supporting documents for this Functional Verification Test plan:

Project Wiki

Primary resource center containing all project documentation.

https://polylearn.calpoly.edu/AY_2014-2015/mod/ouwiki/view.php?id=66785

Reference Documents

The following documents expand on the information available in this test plan:

Existing Non-invasive glucose monitoring research project

This is a detailed article outlining the basic principles behind MIT researchers methods

for measuring glucose levels via a non invasive method

http://www.edn.com/design/medical/4422840/Non-invasive-blood-glucose-monitoring-

using-near-infrared-spectroscopy

https://polylearn.calpoly.edu/AY_2014-2015/mod/ouwiki/view.php?id=66785

http://www.edn.com/design/medical/4422840/Non-invasive-blood-glucose-monitoring-using-near-infrared-spectroscopy

http://www.edn.com/design/medical/4422840/Non-invasive-blood-glucose-monitoring-using-near-infrared-spectroscopy


Use Cases

Overview

A typical user of the non-invasive glucose monitor could be of any age or ethnicity and would

most likely have had prior experience with other invasive devices. It could be presumed that these

types of people are fed up with the traditional invasive methods of glucose monitoring and would

be open to try any non-invasive solution.

Personas

A person who would use this product could be of any age, therefore, this product must be simple

enough for young as well as old people to use. Users of this product are also not limited to just

one part of the world, as anyone could have the need to monitor their blood sugar levels.

Therefore, the simplicity of the design will be necessary so that the device can be used all over

the world by people of any age regardless of whether or not they live in the U.S. or speak english.

The main concerns for the users of this device will be whether or not the device is accurate and if

they will be able to discontinue the invasive methods of glucose measurement.

A specific example of an individual who may who this device is an elderly diabetic who lives

alone. This individual would want a product which does not weigh a lot so that it may not damage

their body, and our monitor would fit this criteria perfectly as we have put a limit on how much

our device can weigh. Because this individual is old in age they would not want a product that

requires them to do complicated steps so that it may work, and in this way our simple one button

setup would be perfect for this individual. Lastly this individual probably would not have a lot of

money, maybe due to the fact that they can no longer work as much as they used to or even the

fact that they are retired. With this low income our device would look very nice to this individual

because we will have a lower price than traditional methods and also lower in price than

comparable non-invasive monitors.

A design goal for this device is compatibility with individuals who have disabilities preventing

the use traditional finger-pricking test kits. A constraint for the device is the user must be able to

administer the device under their own supervision. In order to keep the compatibility spectrum

wide, we’d like to make this device operable under conditions such as partial paralysis,

wheelchair, and other physical inhibitions.


Objective

This is the High Level Functional Verification Test Plan for version 1. The test plan outlines the

following aspects of a Functional Verification Test:

Assumptions

Scope

Test methodology

Entry & exit criteria

Exclusions

Dependencies & responsibilities

Schedule

Risks management

Testing Results and Preparation

Test resources

Defect management for functional test activities

Assumptions

The following assumptions are made for the functional verification test of this project in terms of

glucose solution testing:

● The user will have no cosmetic modifications on their earlobe

● The user will have a large enough earlobe to test upon

● The placement of the device on the users earlobe will be the same globally

Functional Verification Test

Functional verification testing is a type of black box testing that uses the solution specifications,

design document and use case document as a point of comparison to validate that the product is

functioning properly. FVT also needs to ensure the system is working properly and not leading to an

undesired behaviour when an end user uses the device in a way not described in the use cases. FVT

testing is not limited to positive flow tests described in use cases.

.


Functional Verification Test Scope

The tests are responsible for the validation of functional correctness for the following aspects of

the scope:

Phone Application Tests

Validate data received

Validate correct data displayed

Exploratory Testing/Ad hoc Testing

Functional Scenario Testing

Main Flow

User clips ear-piece to earlobe. User then connect earlobe device to phone. Phone then

displays glucose level.

Exception Flow

Alerts user to connect to device if not already connected.

Functional End to End Flow

User connects device to ear, connects device to phone, phone displays value.

Exploratory Testing / Ad hoc Testing

This type of testing will encompass unforeseen errors while using the device/product. These

errors will be addressed as they come along without need for documentation or formal meetups to

address the issues, unless they are major issues. The fixes for these errors will be done by the

person who found the error, with help from others if asked.

Test Methodology

High level test planning is done prior to formal detailed test planning and execution. As part of

the high level test planning the following are determined:

FVT Criteria

FVT entrance criteria

FVT exit criteria

FVT Exception handling for entry and exit criteria

A detailed test case document is prepared based on the project specifications and use cases. The

test case document is reviewed and approved as part of the functional test preparation.


Prior to formal entry into the test execution phase, the Lab environment will be setup with

appropriate operating systems, protocols, and any other pre-requisite software and hardware.

Entry and Exit Criteria

Entry Criteria

The software and hardware development is based on the Waterfall development model.

The following is the post development code and unit test entry criteria for FVT:

Functional verification test preparation can begin once:

Solution specifications are reviewed and approved for the whole project

Use cases are reviewed and approved for the whole project

Functional verification test execution can begin once:

Functional verification high level test plan (this document) is reviewed and

approved

Functional verification test case document is reviewed and approved

Code is complete and has been unit tested for the necessary areas

Exit Criteria

The development is based on Waterfall development model.

Functional verification test preparation can exit once:

All test documents are reviewed and approved

High Level Functional Verification Test Plan

Detailed Test Case Document

Functional verification test can exit once:

All test cases have been attempted and completed

All defects have been addressed

Functional verification test exit checklist is completed, reviewed, and approved

Exception Handling for Entry / Exit Criteria

A document is prepared by the test team lead with the exceptions and associated reason, action

plan, and risks. The document is then reviewed by the solution owner/manager, development

lead, test manager and project manager. The exceptions must be approved before officially

claiming functional verification test entry or exit.

Exclusions

This test plan only covers the testing of glucose solution and does not check the wavelength of

light used in the sensor. The parts for the sensor were chosen based on manufacturer


specifications assumed to be accurate. Especially as the device uses NIR (near-infrared) light,

the wavelength must be trusted to be correct without a spectrometer able to test in the NIR range

of the LED.

Dependencies

The following dependencies will affect the completion and testing phase of the project.

Dependency By (date) By Whom Risk if Not Met

Initial collection of

glucose level

datapoints

2-11-2015 All developers Impedes the accuracy

of the results obtained

by the FVT

Second stage collection

of glucose level

datapoints

2-13-2015 All developers Impedes the accuracy

of the results obtained

by the FVT

Blood glucose

comparison

2-16-2015 All developers Impedes final

completion of the

device

Responsibilities

Role Responsibilities Remarks

Project Manager Oversees the flow of the project Charlie Aylward

Arduino Developer Maintains and oversees Arduino code Jonah Clinard

Android Developer Maintains and oversees Android code Travis Stuever, Jonah Clinard

Designer Oversees and develops the aesthetic

solutions for the project

Travis Stuever

Build Team Responsible for assembling the

hardware elements of the device

Travis Stuever, Charlie

Aylward, Jonah Clinard

Unit Tests Testing individual components of the

entire project

Charlie Aylward


Schedule

Milestone Description Date

Beta Prototype Develop second phase

prototype

2-6-15

Test Plan Develop outline for testing

sensor functionality

2-9-15

Ear Clamp Completion Part developed with CAD and

printed using 3D Printer

2-13-15

Testing Completion Complete test plan 2-18-15

Design Review Review current device and

make needed revisions

2-23-15

Packaging Finalize device aesthetics 2-25-15

Risk Management

Risks

The following risks have been identified in this project:

Functional verification testing assumes the following tests are covered by the

development team:

Software Testing

Hardware Testing

If these areas are not properly unit tested, they could potentially be missed

altogether.

Test Environment - functional testing includes measurements with the LED and

photodiode. The functional test assumes the environment in which the emission and

detection of light will be controlled with negligible outside interference.

Sensor Quality - functional testing of the sensor assumes compatibility between the

photodiode and LED which are both documented to operate at their optimal levels at the

1550nm wavelength mark. Our testing relies on the data presented on the device

datasheets to be accurate.

Test Tracking


Testing Results and Procedures

Test Preparation

The following document discusses our test preparation:

https://docs.google.com/document/d/1mwifIAcCFAVmPiwe6H27z6EnYmH5zYxudx_Qw523_

mM/edit?usp=sharing

Test Execution

The following document is our first run excel spreadsheet:

https://drive.google.com/file/d/0B8HcwAbTkZGVMEh5X2wtc245TmM/view?usp=shari

ng

Test Resources

Hardware

The following machines were used for testing:

Hardware Located Hardware

Specification

Used For Contact Person

Android Phone Jonah’s person Android 3.0+ Displaying

Glucose Level

Jonah Clinard

Software

Software Version License Type Where to

download

Contact Person

Android Version 4.4.4 Free Pre loaded with

phone

Google

Gluco-medes app Version 1.6 Free Not available to

download

Gluco-medes

Team

Arduino IDE Version 1.0.6 Free Arduino.cc Arduino

https://docs.google.com/document/d/1mwifIAcCFAVmPiwe6H27z6EnYmH5zYxudx_Qw523_mM/edit?usp=sharing

https://docs.google.com/document/d/1mwifIAcCFAVmPiwe6H27z6EnYmH5zYxudx_Qw523_mM/edit?usp=sharing

https://drive.google.com/file/d/0B8HcwAbTkZGVMEh5X2wtc245TmM/view?usp=sharing

https://drive.google.com/file/d/0B8HcwAbTkZGVMEh5X2wtc245TmM/view?usp=sharing


Staffing

Name Phone E-mail Location Title

Travis

Stuever

970-403-4040 [email protected] San Luis

Obispo

Design/Application

Specialist

Jonah Clinard 805-550-4957 [email protected] San Luis

Obispo

Application/Hardware

Specialist

Charlie

Aylward

530-774-6696 [email protected] San Luis

Obispo

Implementation

Specialist and Team

Leader

Defect Management

Defect

A defect is when the software/hardware fails to display/calculate the user’s glucose level.

Defect Severity

Defects are classified by severity. Defect severity levels can only be changed by the defect’s

originator or by concurring with the originator or test lead. Severity levels are defined as:

SEVERITY 1 - A severity 1 defect involves a hardware failure to calculate a glucose level.

Schedules are impacted. A problem fix and problem retest is required before any test activity

can effectively proceed. The defect must be resolved within 48 hours and a fixed test driver

must be delivered to the test team as soon as possible after the defect is fixed; so that testing can

resume. When the problem is fixed, the test execution record may not be closed as complete

until a supported build containing the fix has been delivered to the test team.

SEVERITY 2 - A severity 2 defect represents a significant functional defect with the android

application. This defect may invalidate continued testing in the functional area. The defect may

mask the further detection of problems in the functional area affected. A problem fix and retest

is required before test activity can proceed in the functional area. The next scheduled build (no

more than 10 days later) must resolve the defect. When the problem is fixed, the test execution

record may not be closed as complete until a supported build containing the fix has been

delivered to the test team.


Defect Reporting System

All defects will be reported to the entire team and then a discussion will ensue on where the

defect is located and the severity of the defect. The team will then delegate a member to fix the

defect and report back when it has been resolved.

Defect Reporting Data

We will keep a cloud based copy of all reported defects.

Defect Validation

When a defect is fixed, the team is notified via email. The team then follows the steps that

produced the defect to ensure the defect is fixed.

Specific Tests:

Drop Rate Tests: This series of tests will look at the change in intensity with a single drop of

glucose water, over the course of multiple drops or saturation. This test is for looking at how the glucose

concentrations in the glucose water we are using is affecting the intensity level of light we are recording.

To pass these tests the drops must register a difference in the intensity we see as more drops are

added to a vial.

Change In Intensity Tests: This set of tests will focus on the difference in intensity levels we

see as different glucose solutions are tested. For instance, a 50 mg/dl solution will have a different

intensity than a 200 mg/dl glucose solution. These tests will cover a varying amount of liquid tested

against, meaning glucose solutions will be tested with 15 drops of glucose water in each sample and then

the next test run will have 18 drops of water to see if there is a consistent trend across the amount of water

used. These tests will also cover different factors outside of the glucose samples. Examples include

varying the ambient light outside of the testing environment, the distance between the samples, LED, and

photodiode.


In order for these tests to pass they must show a difference between the glucose samples being

tested against and also have a visible trend to extrapolate data from the results.

Component Tests: This set of tests will see if the LED and the photodiode are working as

expected. We will set up the LED and photodiode and see if the photodiode receives more light as the

LED comes closer and less as it goes away by outputting the photodiode levels to a serial connection.

To pass this test the LED photodiode must output a higher number the closer the LED is to it and

a lower number as it goes farther away.

Application Test: This test is for the application specifically, where we test the full

functionality of the app. We see how the application reacts to not being connected to the device,

plagued by excessive recalculation tests, and purposefully sending bogus data.

The criteria for passing these tests is to perform without error, or crashing. Basically, the

app must function as designed with no visible problems.

Calibration Process

After the development of the beta prototype we are able to begin calibration on the device. The

Calibration of the device will be performed as follows: (please note this is assuming we have

gotten our beta prototype functioning)

● First we will obtain a range of glucose solutions with tested and specified nominal levels.

● We are using a curve fit for our solution to measurements, therefore we have taken many

many data points and have devised a trend from this data.

● This best fit curve has been programmed into the device in the form of a software

algorithm.

● We will then compare the readings the device gives us to the true readings as reported by

the controlled solutions.


● If we obtain any outliers they will be noted, and if we receive enough outliers at a given

measurement range we will note the device as being defective, or depending on the

severity of the outlier, adjust the devices software accordingly.

● This will be performed on several different devices, each with the identical build

specifications. We will record the results of the all these devices and then extract which

ones are defective, and which devices produce the same results. If a majority of the

devices (80%) produce the same true results as reported by the solutions then we can

confirm that these devices are functioning properly.

Bug Tracking

We are using github as our version control manager. Each iteration marking a major design

change is pushed into a new branch. Each branch contains multiple revision histories specifying

both major and minor updates. If a bug is encountered in a pushed revision then it is noted in the

versions notes. The software team will then try and replicate the bug and then attempt to fix it. If

the bug is verified as fixed it will be updated and pushed to the repository documenting and

listing any changes that were made.


Conclusion

The result of the effort put toward making this device was far from the goals in the initial design

plan. However, going into this project, the limitations and potential obstacles were made clear.

Thus the struggles we encountered during the development process did not come with a surprise.

The beta prototype will be the hand off project to be continued by another design group. The

most challenging obstacle we faced while creating the device was the conceptual proof of the

theory on which the device design was based off of. The lack of informative research combined

with our tight budget made for a difficult challenge in creating a non-invasive glucose

monitoring solution. Our group put forth a great effort in ensuring we crosschecked all of the

design decisions to ensure we didn’t make a mistake in our approach to the problem.

Unfortunately, we were unable to observe a data trend in the NIR light attenuation through

varying levels of glucose solutions. This step was necessary to move forward in the product

design. We do have ideas to fix the issues we had should further investigation be performed on

the device prototype. The main improvement to be made to the system is an increase in the

intensity of the light source by using multiple LEDs of the same model/wavelength.