Download (MAV) Medical Automated Vitals System

MAV: Medical Automated
Vitals Measurement System
University of Puerto Rico,
Mayagüez Campus
TI Innovation Challenge 2015 Project Report
Team Leader:
María D. Jiménez, [email protected]
Team Members: Aaaalf Alfredo Cox, [email protected]
Team Luis R. Murphy, [email protected]
Team Luis E. Vega, [email protected]
Advising Professor:
Manuel Jiménez, [email protected]
Video
Provide link to video that you’ve uploaded to
www.ti.com/videos
Texas Instruments
Mentor (if applicable):
Date:
Qty.
List all TI analog IC
and TI processor part
number and URL
1) Explain where it was used in the project?
2) What specific features or performance made this
component well-suited to the design?
1
CC3200
This is the Main core of the project, the MCU used for the application. This MCU
was chosen for its wide variety of pins, its capability of connecting to the internet
without and external module.
1
TMP007(Temperature
Sensor)
It was used in the Temperature module of the system.
It's an IR temperature sensor that works with I2C, that makes the connection to
the MCU more efficiently, just 2 jumpers and a GND.
2
TPS5410-EP (Step down
Converter)
This chip was chosen to regulate the voltage through the system to the necessary
voltage needed in the specified module receiving power.
3
LM741J(quad op-amps)
Was use to create instrumentation amplifiers on the pressure module and on the
pulse sensor. Was chosen for the efficiency of having multiple op-amps in a single
chip.
Submit your TI Innovation Challenge project to http://tiic-na.hartehanks.com. Your team is
encouraged to post your project as early as possible- Your submission will be kept offline
until the contest has officially closed!
Instructions:
 Submit your project and include the following documents
o Your full class report, which much include this TI project report.
o Upload a video of demonstrating your project to www.ti.com/vidoes (must log
into my.TI) and provide the link to that video in this project report. We’d love to
see your team engaging with TI products!
o Link to supplemental photos
MAV (Medical Automated Vitals) System is a system that is intended to ease
the workload on the average nurse by automating the vital signs measuring of
patients, such that a nurse can focus on tasks of higher criticality and the simple
interpretation of the patient’s physiological state. The system consists of a band that
includes the necessary hardware and software to measure heart rate, blood
pressure, temperature, the capability to send this information to a database and a
user interface that allows the nurse to view the database’s information in an effective
and intuitive manner. An air cuff inflation system is also present that works in
conjunction with a pulse sensor to detect systolic and diastolic pressure; whenever
the system detects a value that is outside acceptable ranges, it triggers an alarm that
nurses should tend to immediately.
Please submit your class report with this one page document. Your class report should include
the following (Max of 10 pages, excluding appendix):
 Table of contents
 List of figures and tables
 A detailed written description of the project design
 Hardware Design
 Any Software Architecture used (include any software code as part of Appendix)
 Testing and Results / Conclusions
 Future Work / Recommendations
 Acknowledgements and/or References
 Appendix: schematics, CAD drawings, Critical IC Bill of Materials, User Manual, etc.
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MAV: Medical Automated Vitals Measurement
System
Alfredo Cox Vega
Luis E. Vega González
Luis R. Murphy Marcos
María de los A. Jiménez Vélez
For: Professor Manuel A. Jimenez
Course: ICOM 5217
Date: May 21, 2015
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Table of Contents
Abstract .......................................................................................................... Error! Bookmark not defined.
Table of Contents ......................................................................................................................................... iv
1 Introduction ................................................................................................................................................ 8
2 Theoretical Background ............................................................................................................................. 8
2.1 Nursing Necessity ............................................................................................................................... 8
2.2 Photoplethysmography ....................................................................................................................... 8
2.3 Acceptable Vital Signs Ranges ........................................................................................................... 9
3 System Specifications ................................................................................................................................ 9
3.1 System Requirements.......................................................................................................................... 9
3.2 System Features ................................................................................................................................ 10
3.3 System Limitations ........................................................................................................................... 10
3.4 System Components.......................................................................................................................... 10
3.4.1 Communications ........................................................................................................................ 10
3.4.2 User Interface ............................................................................................................................. 10
3.4.3 Control Scheme .......................................................................................................................... 10
3.4.4 Microprocessor .......................................................................................................................... 10
4 System Overview ..................................................................................................................................... 11
4.1 System Explanation .......................................................................................................................... 11
5 System Reliability .................................................................................................................................... 11
5.1 Privacy .............................................................................................................................................. 11
5.2 Safety ................................................................................................................................................ 11
5.3 Power Efficiency............................................................................................................................... 11
6 Software ................................................................................................................................................... 12
6.1 Explanation ....................................................................................................................................... 12
6.2 MCU Memory Usage (Program & Data) ........................................................................................... 13
6.3 Software Completion ........................................................................................................................ 13
7 Hardware Completion .............................................................................................................................. 13
7.1 Pulse Sensing Module ....................................................................................................................... 14
7.2 Temperature Module ......................................................................................................................... 14
7.3 Pressure Module................................................................................................................................ 15
7.4 Alert Module ..................................................................................................................................... 15
7.5 Power Analysis ................................................................................................................................. 15
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7.6 Timing Analysis ................................................................................................................................ 16
8 User Guide ............................................................................................................................................... 16
8.1 Installation Guide .............................................................................................................................. 16
8.2 Operation Guide ................................................................................................................................ 16
9 Conclusion ............................................................................................................................................... 17
9.1 Future Works .................................................................................................................................... 17
10 References .............................................................................................................................................. 18
11Appendix ................................................................................................................................................. 19
11.1 Figures and Images ......................................................................................................................... 19
Figure 1: Transmissive (left) vs. reflective (right) PPG ................................................................ 19
11.1.1 Block Diagram .......................................................................................................................... 20
Figure 2: Block Diagram Representation of the System ............................................................. 20
11.1.2 State Diagram........................................................................................................................... 21
Figure 3: System State Diagram .................................................................................................. 21
11.1.3 Power Diagrams ....................................................................................................................... 21
Figure 4: Power Schematic View ................................................................................................ 21
Figure 5: Power Module system view ......................................................................................... 22
11.2 System Conception ......................................................................................................................... 22
11.2.1 Global System View.................................................................................................................. 22
Figure 6: Global System View...................................................................................................... 22
11.3 System Schematic ........................................................................................................................... 23
Figure 7: System Schematic ........................................................................................................ 23
11.4 User Interface-Level ....................................................................................................................... 24
11.4.1 Arm Band ................................................................................................................................. 24
Figure 8: Arm Band System View ................................................................................................ 24
11.4.2 Computer Interface: ................................................................................................................. 25
Figure 9: User interface web page that show a dashboard ........................................................ 25
Figure 10: User interface web page that show a patient information ....................................... 25
Figure 11: User interface web page to add a new arm band to the system............................... 26
Figure 12: User interface web page to configure an armband and link it to a patient .............. 26
11.5 System Flowcharts .......................................................................................................................... 27
11.5.1 Timer ISR................................................................................................................................. 27
Figure 13: Timer ISR .................................................................................................................... 27
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11.5.2 Pulse ISR ................................................................................................................................. 27
Figure 14: Pulse ISR ..................................................................................................................... 27
11.5.3 Pressure Meassurement Algorithm .......................................................................................... 28
Figure 15: Pressure Measurement Algorithm............................................................................. 28
11.5.4 Main Software Plan.................................................................................................................. 29
Figure 16: Main Software Plan .................................................................................................... 29
11.5.5 Database ER Diagram .............................................................................................................. 29
Figure 17: Database ER Diagram ................................................................................................. 30
11.5.6 Button ISR ............................................................................................................................... 30
Figure 18: Button ISR .................................................................................................................. 30
11.5.7 Blink LED and Buzzer Flowchart ............................................................................................ 31
Figure 19: Blink LED and Buzzer Flowchart ................................................................................. 31
11.5.8 Alert Flowchart ........................................................................................................................ 31
Figure 20: Alert Flowchart........................................................................................................... 31
11.6 Formulas ......................................................................................................................................... 31
Equation 1: Resistance for the passive RC HPF ........................................................................ 32
Equation 2: Frequency acquired for pulse sensing module ........................................................ 32
Equation 3: Resistance for low pass filter ................................................................................... 32
Equation 4: DC gain Calculation .................................................................................................. 32
Equation 5: R1 from DC Calculation ............................................................................................ 32
Equation 6: Gain potentiometer modification............................................................................ 32
Equation 7: Pulse Sensor Final Output Voltage .......................................................................... 32
Equation 8: Pressure Amplification............................................................................................. 32
Equation 9: LED Collector Resistance ......................................................................................... 32
Equation 10: LED Base Resistance .............................................................................................. 33
Equation 11: Battery life ............................................................................................................. 33
Equation 12: total current consumption when active MCU ....................................................... 33
Equation 13: Total Current Consumption when MCU is in low power mode ............................ 33
Equation 14: Active Battery Life.................................................................................................. 33
Equation 15: Low Power Batter Life ........................................................................................... 33
Equation 16: Expected Battery Life ............................................................................................. 33
11.7 Tables .............................................................................................................................................. 33
11.7.1 Acceptable Vitals Values .......................................................................................................... 33
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Table 1: Average heart rate by age. [1]....................................................................................... 34
Table 2: Systolic and Diastolic Blood Pressure Range Table. [2] ................................................. 34
Table 3: Body Temperature Classification Values [3] ................................................................. 34
11.7.2 Voltage and Current Consumption Table ................................................................................ 34
Table 4: Voltage and Current Consumption Table ...................................................................... 35
11.7.3 Software Completion Table ..................................................................................................... 35
Table 5: Software Completion Table........................................................................................... 35
11.7.4 Hardware Completion Table .................................................................................................... 36
Table 6: Hardware Completion Table ......................................................................................... 36
11.7.5 Work Distribution..................................................................................................................... 36
Table 7: Work Distribution Table ................................................................................................ 36
11.8 Bill of Materials .............................................................................................................................. 36
Table 8: Bill of Materials ............................................................................................................. 39
11.9 Team Members ............................................................................................................................... 39
Figure 21: Team picture, from left to right Luis E. Vega, Maria D. Los Angeles, Alfredo Cox, Luis
R. Murphy.................................................................................................................................... 39
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1 Introduction
Throughout the years, the occurrence of new illnesses has affected people worldwide
and have been increasing; as a result, the demand for professionals in the medical field has
been increasing due to the high patient count in hospitals. This occurring high patient
countaffects treatment time due to the increase in patient to nurse ratios in hospitals and
clinics:the patient to nurse ratio in the US (including Puerto Rico) is an average of 20:1 and
can reach up to a 40:1 ratio [3].Nurses are in charge of direct human interaction, interpretation
of the patient’s current physiological stateand measuring patient vital signs amongst other job
requirements. Vital sign measurements are taken as part of the admittance exams in hospitals
and as check-up measurements in clinics that must be repeated per patient. Patients are
monitored for a set period of time; this time is dependent on the patient’s conditions and the
doctor’s diagnosis of the patient. The time lapses between a patient monitoring occurs
because of potential situations nurses might have per patient, affecting the diagnosis of the
consecutive patients and the effective monitoring due to the shift in measurement times.
In order to address this situation, several products exist on the market that
automatically measure the most prominent vital signs (eg. heart rate, blood pressure). Robust
solutions typically make use of electrodes which restrain the patient to a bed, and most portable
solutions available for consumers are exercise-oriented and not precise enough to be used in a
medical environment. In both of these cases, the systems are geared for individual users, not
multiple users. In a hospital, these single user systems are restricting and take a toll on a nurse’s
time distribution per patient, increasing the inaccuracy of the vitals measurement; hence a system
that allows the control and automation of patient vital sign measuring, while giving the patient the
freedom of mobility, will help the accuracy of measurement readings at specified intervals,
enable nurses to monitor a group of patients at the same time, record obtained measurements to a
database, and grant the patient comfort.
The system developed, named MAV System, consists of measuring bands, a user
interface (UI) to view information and control the bands, and a database on a server to store the
measurements taken. The system’s users include the group of patients that will wear the bands for
the duration of the time that they are under observation, and the nurse or doctor that analyze the
database with the measurements obtained for each individual patient in the group. The bands’
parameters should be programmable via the UI by the health professional; specifically, the patient
assigned to it, the time lapse between measurements and the thresholds for critical vital signs
according to the patient’s characteristics. In addition to controlling the behavior of the bands, the
UI should display a history of the last vitals taken. The history of vital measurements obtained
over the desired time frame should be stored in a database to optimize a user’s critical thresholds
over time.
2 Theoretical Background
2.1 Nursing Necessity
Part of a nurse’s daily schedule consists of taking the vital signs of the many patients
assigned to the nurse’s shift. As nurses from Peres Hospital expressed and Dr. Gloribell Ortiz
confirmed, this task is among the most time-consuming of the daily chores, owing to the high
patient-to-nurse ratio in the U.S. (including Puerto Rico), which has an average of 20:1, and
can reach a peak of up to 40:1. Although there are several products on the market that
automatically measure the most prominent vital signs (eg. heart rate, sometimes blood
pressure), robust solutions typically make use of electrodes, which tie the user to a bed, while
more portable solutions are exercise oriented. In both of these cases, the system is geared for
individual users, not groups of people. For these reasons, a system that is intended for the
automatic measuring and tracking of the vital signs was designed.
2.2 Photoplethysmography
Pulse sensing technology has advanced to the point that wearable devices can be
produced to measure these signals. Heart rate is primarily measured with one of two
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technologies: electrocardiography (ECG) and Photoplethysmography (PPG). ECG measures
the electrical signals generated by the heart pumping, while PPG uses light based means to
estimate the blood flow through the skin. Both methods are non-invasive and inexpensive.
Photoplethysmography relies on skin’s rich perfusion, that is, the ability of its
capillary bed to absorb blood. Skin’s perfusion is especially noticeable in thin areas, such as
the fingertip or earlobe. Therefore, when the heart pumps, the increase of blood in these areas
is easily detectable. This can be seen by simply lightly squeezing a finger. PPG typically
measures the blood’s oxygen saturation using a pulse oximeter by illuminating the skin and
measuring the emitted light’s absorption or reflectivity at a certain time. When using
reflective PPG, it is preferred to use infrared light, because pumped blood has a higher
amount of hemoglobin, which reflects infrared light (wavelength greater than 700nm) better.
To measure reflective PPG, an infrared opt couple is used, where both the emitter and
receiver are on the same side of the finger, as seen in section 11.1 Figures and Images:Figure
1. When there is no finger placed on the couple, the photo sensor remains in cutoff. On the
other hand, when a finger is placed on the couple, the IR light is reflected and the photosensor conducts current. The pulse sensing lies the fact that when oxygenated blood is
pumped and flows through the finger, it reflects IR light better, thus increasing the current
through the transistor.
The signal output by the opt couple is noisy and includes a DC component owed to
skin and tissue. To remedy this, the signal is passed through low pass filters and high pass
filters. The low pass filters remove the noise and the high pass filters remove the skin’s DC
component. The low pass filters are active, which amplify the signal. The final output
resembles a train of pulses that rise when a pulse occurs.
2.3 Acceptable Vital Signs Ranges
The sensors will be periodically collecting data. When these values are out of certain
ranges, the system should alert the personal in charge. Section 11.7 Tables: Tables 1 to
3indicate the acceptable ranges for pulse, blood pressure and temperature, according to the
American Heart Association and Prof. Ortiz. As observed in section 11.7 Tables: Table 1,
Tachycardia is diagnosed when the pulse is higher than 100 beats per minute. Bradycardia is
diagnosed when the pulse is lower than 60 beats per minute.
Blood
pressure
is
measured in millimeters of mercury (mmHg) and several factors affect it, namely:





age
exercise habits
stress
race
sex
Section 11.7 Tables:Table 2 has a record of the acceptable ranges of blood pressure
according to the American Heart Association.A vital sign that doesn't vary much is the body
temperature, some of the factors can produce changes on it are the local temperature of the
area, the state of the patient, or any sickness that may cause the body to produce fever.
Section 11.7 Tables:Table 3 illustrates the acceptable ranges of the body temperature.
3 System Specifications
3.1 System Requirements

The MCU must be able to calculate arithmetic for the measurements of pressure,
temperature, and heart rate.
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








The MCU must be able to communicate with the database server through a wireless
network.
The MCU’s behavior must be controllable using the UI.
The band system must include hardware that supports communication with the UI when
used for the first time.
The MCU must be able to receive and interpret sensor data.
The system must be able to communicate with the patient and assigned nurse using LED
and speaker.
The UI must be able to communicate with the server.
The MCU must communicate with the compressor and valve operations.
The MCU must be able to communicate with the pressure, temperature sensors.
The system mounted on the band must not cause discomfort on the patient.
3.2 System Features




The system will automatically measure at time intervals set up by the nurse or medic.
The system alerts if any of the measurements are outside the acceptable range of values.
The UI must be able to access tabulated data and show the data in a visual manner.
The UI must be able to connect with multiple armbands.
3.3 System Limitations


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
Power must be maintained for at least 24 hours.
In the case of power loss, time management between time intervals must be maintained.
Sensor accuracy.
The system must be comfortable for the patient to wear in a 24 hour interval.
The system is limited to Wi-Fi range.
The data exchanged by the UI, server and band cannot be readable by external sources.
3.4 System Components
3.4.1 Communications
The System will use Wi-Fi to establish a communication between the UI, the Server with its
database and the armband device. This communication was chosen because the system
environment is the hospital and Wi-Fi is a service that the hospital already has. Moreover, if we
compare the Wi-Fi with Bluetooth, in matters of range, the Bluetooth range would not suffice for
the intended length between the room and the server.
3.4.2 User Interface
The User Interface will be a software based program that will communicate with the server,
storing patient information and the starting inputs of each armband into the database for the MCU
to read. Also this User Interface will have the ability to give visual representation of the data in
the database.
3.4.3 Control Scheme
For this system the time interval for measurements provided by the nurse through the UI will
determine the quantity of times the armband will inflate and deflate in order to take the
required blood pressure measurements. Also the inputs from the nurse will specify to the
armband which are the accepted values for the patient. Given this, the microprocessor will
monitor and control all sensor measurements and the frequency of these measurements. Also
all alerts will be controlled by the microprocessor depending on the values retrieved.
Furthermore, the MCU will serve as a control system to the compressor and valve.
Additionally, the band’s pushbutton will be used to control its state.
3.4.4Microprocessor
For the development of the system proposed a microprocessor is required. A microprocessor will
provide our system with the necessary I/O interfaces, processing needs and system specifications
required for the correct implementation of the system hardware and software. Some of the
specification that need to be addressed are Wi-Fi, memory, and the synchronization between
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sensors and the alert system. The I/O interfaces are the sensors, pushbutton, speaker, LEDs,
micro-USB communication, compressor and valve. The system processing needs are interpreting
sensor data, comparing with accepted values, and transmitting it via the wireless network.
4 System Overview
4.1 System Explanation
The MAV System consist of a CC3200 Microcontroller unit as a core that can connect to
the internet to establish a connection with a database system. It also have a temperature
component, TMP007, which connects through I2C with the CC3200 transmitting what would be
temperature in a digital manner. Other of the components in the MAV System is the pulse sensor
module that consist of an Easy pulse board embedded system that will react with an IR sensor to
the pulses of the human body and send 3V impulse to the MCU each time it registers a pulse. An
alert module that consist of a LED, a buzzer and a button provide interaction with the outside of
the system each time a measurement is not on the acceptable values. The final component of the
MAV System would be the power supply that consist of 3.7 V lithium rechargeable battery with
its recharge station and a booster to supply 5 V to the compressor and the valve components on
the Air Compression Module. All of this is shown on the block diagram in section 11.1.1 Block
Diagram:Figure 2.
5System Reliability
The three mayor specifications in which the system was developed. These
specifications are privacy, safety and power efficiency.
5.1 Privacy
Privacy is one of the main topics of concern when you analyze the system, since it
involves getting personal information of a person's health status. When dealing with patient
medical information there is a law called HIPAA Law that protects the information of each
patient.
HIPAA stands for Health Insurance Portability and Accountability Act and its
primary goal is to make it easier for people to keep health insurance, protect the
confidentiality and security of healthcare information and help the healthcare industry control
administrative costs. The current action taken to ensure the safety of the patient’s information
is to use the Parse platform to generate the data base and the connections between the
database and the MCU. These connections are made by HTTPS and SSL, and Parse will
reject all non-HTTPS connections, which means that a successful attack to access the
personal information of any patient is very difficult.
5.2 Safety
The safety of the patient is considered by giving the alert module priority over any
interrupt or continuing the main function. As soon as an unacceptable value is read, the alert
module turns on and demands attention from a nurse in charge, by both noise from the buzzer
and a blinking LED. Additionally, when measuring pressure by filling the air cuff, a safe
pressure value was chosen such that in general, the patient won't be harmed by over inflation
of the cuff.
5.3 Power Efficiency
In order to consider power efficiency in our design, the program was designed to
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remain in sleep mode for as long as possible. The system wakes up whenever it receives a
pulse, every second and when it is time to measure blood pressure. In the first two cases, the
MCU wakes up to increase a variable through the ISR, check flags in the main function and
return to sleep mode if there is no unacceptable values, which is done in a matter of micro
seconds. When it measures pressure, it remains on to fill up the air cuff twice and measure
the pressure entered through the ADC.
6 Software
6.1 Explanation
The MAV System like any other programmed device uses a flow of process that makes it
reach its function, that process will be explain here with a series of steps that can be explain
following the state diagram:
1. What is first needed is to establish a connection with the hospital Wi-Fi, this can be
illustrated in the diagnostics and setup mode, here a pop up window will appear
asking for the internet's name and its password, that input is entered the system will
establish connection and store it in the MCU.
2. Once the connection with the internet is established the system will be able to operate.
The next step for usage is to enter the patients data, the band ID to be used, this ID is
provided, and the monitoring time interval on the UI so that it could pass that data
into the database.
3. Then the band could be attached to the patient. Once attached the system can be
turned on, on that moment the system will follow section 11.5.4 Main Software
Plan:Figure 16, to establish connection with the database, receive and store that data.
4. When connection to database is assured and the patient’s data has been uploaded to
the system the system will wait 1 minute to generate heart rate and temperature
measurements to then generate the first pressure measure.
5. Once any of the measures are done the system will make sure to verify if the measure
is within the acceptable value, if the measured value is not the system will make a
store on the database and generate and alert in both the User Interface and the patient
room, following section 11.5.8:Figure 20. If an alert is triggered a health professional
must go to the room and press the button to turn off the alarm.
6. If the measure is within acceptable values the system will store the values on the
database and go directly to low power mode, regardless if it's the first measure or not.
The system will get out of low power mode in three occasions:
 Every time the system registers a pulse to make the count of the pulse,
following section 11.5.2 Pulse ISR:Figure 14.
 Every minute to have a monitoring value of what is the heart rate and the body
temperature, following section 11.5.1 Timer ISR:Figure 13, and then enters
low power mode again.
 Once the time interval establish by the health professional is over, when this
happens the system will measure blood pressure and the system will check
once again if the measurements are acceptable and if they are it enters low
power mode again.
Once the 6 steps are over the system will maintain itself in this step until turned off.
As an overview, the system will first establish connection with the database and if
successful will receive all the data of the patient. Once established, the system will prepare
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itself for the first measurement, and once measurement is done, it will check if it's acceptable,
and the system will enter low power mode and wait until the established time interval is over
to generate another measurement and store it in the database. If the value is not acceptable,
then the system will store this data and generate an alert to the UI and in the room to get the
patient some attention.
6.2 MCU Memory Usage (Program & Data)
In terms of data since the system uses a database for keeping the record, the MCU just
uses approximately 48 bytes in RAM memory to be able to temporary store each measured
value to be stored in the database in a variable. However, in program memory the main
memory takes around 60 KB in C and the CC3200 has an SRAM capacity of 256 kB. The
ROM is used to store the Wi-Fi internet.
6.3Software Completion
When the project specifications were made, it was decided that the vital signs the
system would measure would be pulse (or heart rate), blood pressure, and temperature. For
this reason, development of the project’s software was divided into the following modules:
Setup of Wi-Fi and connection to the database, timer and interrupt setup, I2C communication
for the TMP007 temperature readings and low power mode setup; section 11.7 Tables: Table
5 divides the software parts in sections and shows the level of completion each section has.
To connect the CC3200 to a local access point, the Simple Link APIs were used to
configure WLAN, using a command line application to prompt the user for an SSID,
password and security type. Once Wi-Fi is configured, the CC3200 initializes its database
connection and retrieves the ID number that will be used to identify the band among the other
connected to the database. The system’s database is powered by Parse, a platform that
provides an API for embedded C applications.
When main operation is entered, timers, interrupts for timers and GPIO pins used by
pulse are configured and the MCU enters low power mode, awaiting interrupts. If the GPIO
pin assigned to the pulse sensor receives a high voltage, then the edge triggers an interrupt
that counts the pulses and sends the CC3200 back to sleep mode. This continues for sixty
seconds, after which the timer interrupts the system to store the pulses-per-minute and current
temperature values in memory.
To measure the temperature value, the pins required for I2C communication between
the CC3200 and the TMP007 must first be established. Once established, the TMP007 must
be set as a slave to the master CC3200 and configured to read die temperature. After the IC is
setup, temperature can be read. Temperature data is 16 bits long, which requires the data to
be sent over two bursts. The most significant byte is sent first.
7Hardware Completion
Once a clear picture of the hardware design was obtained, the modules were to be
built in such a way that they work independent of each other. The modules all provided
signals to the MCU via different channels (I2C, GPIO, ADC), such that the CC3200 would
be the only link between all of the modules;as shown in section 11.7 Tables: Table 6, an
overview of the hardware completion table is described.
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The pulse sensing circuit is designed to form an analog signal chain, where the output
signal follows binary logic: 1 for pulse received, 0 for no pulse. The chain consists of the
analog pulse sensor and the conditioning of the signal, as this is enough to output the train of
pulses expected. The IR sensor’s sensitivity is crucial to the correct operation of the circuit.
As was tested, a normal pair of IR emitter and receiver would not be sensitive enough to pick
up the slight variation in voltages pulse produces. The TCRT1000 on the other hand blocks
visible light and reacts very visibly to the changes in voltage. The final processed signal is
robust enough to send accurate interrupts periodically to the MCU, such that BPM can be
easily measured in injunction with a timer. From the pulse sensor’s perspective, the MCU
only needs to wake up to mark a received pulse (increase a variable, in this case) and can
immediately enter low power mode.Up next a brief explanation of how each module work
will be given.
7.1 Pulse Sensing Module
According to A wearable prototype of reflective sensor for non-invasive measurement
of heart rate, the signal conditioning for the sensor’s output should consist of an RC high
pass filter with a cutoff frequency of 0.7Hz to impose a lower limit of 42BPM and remove
the DC component the skin adds to the output signal; and an active low pass filter with a
cutoff frequency of 2.34Hz to impose an upper limit of 140BPM and remove noise from the
power supply.
To implement the passive RC HPF with a cutoff frequency of 0.7Hz, with a tantalum
capacitor of 4.7uF that was readily available, the resistance value to be used is shown in
section 11.6 Formulas: Equation 1.The closest available resistor values were 47k and 51k.
The 47k resistor was chosen because it provides a higher cutoff frequency, blocking off a
bigger low frequency component of the signal. The new cutoff frequency was found to be
what is shown in section 11.6 Formulas: Equation 2.
To eliminate the noise, a low pass filter was to be cascaded with the high pass filter. It
is noted that the signal still needs amplification, especially after having been processed
through a passive filter. To do so, an active LPF is used. The high pass closed loop circuit
used was a resistor and capacitance in parallel. Using a ceramic capacitor of 100nF, the
resistor necessary is illustrated in section 11.6 Formulas: Equation 3.Although a 680k
resistor was not at disposal, an equivalent resistance consisting of two 330k and two 10k
resistors in series was used.
To add gain to the active filter, a resistor is added between the inverting input and
ground. DC gain is calculated according to section 11.6 Formulas: Equation 4, where R1
value is shown in section 11.6 Formulas: Equation 5 which is a resistor value already
available.The full gain of the circuit is expressed by the product of the gain of both active
filters shown insection 11.6 Formulas: Equation 6. The gain can be modified with the
potentiometer setting.The final output signal has maximum voltage level of 5V. This is
lowered to 3V using a voltage divider. If R1 is 1.8k, then R2 is calculated from the following
section 11.6 Formulas: Equation 7.
7.2 Temperature Module
Temperature module uses I2C that works as a master slave connection with the
CC3200 SCL and SDA pins. Calculations done in this module are specified strictly on the
14
TMP007 datasheet, in which it specifies that the value that is received by the chip to the
CC3200 must be shifted twice to eliminate the two least significant bit and a multiplication
by 0.03125 to convert the value given to C°.
7.3 Pressure Module
The pressure module consists of two stages, the 2SMPP-03 pressure sensor and an
instrumentation amplifier. The pressure sensor is a resistor bridge that outputs a differential
voltage (that can be positive or negative). This voltage is relatively small and require
amplification. Therefore, it requires amplification, and the amplifier must be able to saturate
at negative voltages. If the amplifier is designed correctly, the gain can be controlled with a
single resistor according to section 11.6 Formulas: Equation 8, where every resistor inside
the amplifier is of equal value and Rgain is a resistor that can be controlled. This circuit
consist of 3 Operational amplifiers which the first two are connected to the output of the
pressure sensor and the output of each of these two op amps are the input of the third op amp
which leads into the CC3200 ADC pins. The CC3200 ADC pins have 12 bits of resolution
and the input that is received is 32 bits long. The result of the input signal actually goes from
pin 2 to pin 14 of the 32 bit long number. To be able to receive this number what is done is
make a logic AND software wise by 0x3ffc and shift the result of the logic AND by 2 to the
right.
As part of the pressure module there is also the compressor and valve functions which
are implemented inside of this module. These component need a type of amplifier to make a
connection to control the CC3200 and the motor and valve. For the Motor there is a
Darlington Driver connected between the MCU and itself, and for the valve a BJT NPN
transistor is used for control.
7.4 Alert Module
The alert module includes a green LED that flashes when alerts occur. It is driven by
a 2N3906 PNP BJT, so it can turn on when the CC3200 is in sleep mode. To calculate the
resistance in the collector to prevent LED burnout, a KVL was used as shown insection 11.6
Formulas: Equation 9,where 1V is the emitter to collector voltage, 3V is the LED forward
voltage and 15mA is the LED’s forward current. The base resistance was then calculated with
another KVL, as shown in section 11.6 Formulas: Equation 10.
7.5 Power Analysis
The system power analysis consists on making sure the power supply will be enough
to feed the system and result fully functional. In order to accomplish this, we need to
determine which voltage and current values are needed so that every module can work
properly. Section 11.7 Tables: Table 4 has an overview of voltage and current consumption
that each powered module has.
The power supply selected for the system is a 3.7V and 1200mAh lithium battery with
the capability of recharging itself, and as we can see in section 11.7 Tables: Table 4, they are
components that need more than 3.7V which means a booster is needed to rise the voltage
from 3.7V to 5V. Section 11.1.3 Power Diagrams:Figure 4 gives a graphical representation
of the power supply module and section 11.2 System Conception:Figure 5 is a graphical
representation of the power supply connected to the components mentioned in section 11.7
Tables: Table 4.
15
Battery life of the system can be calculated as shown in section 11.6 Formulas:
Equation 11, since the system will be constantly changing from active mode to low power
mode we need to estimate the battery life by taking into consideration both. Using the section
11.7 Tables: Table 4 information, we calculate the battery life of the system as shown in
section 11.6 Formulas: Equation 12, which shows the total current consumption of the
system when the MCU is in active mode and section 11.6 Formulas: Equation 13 shows the
total consumption in low power mode, with these values we can roughly estimate the system
expected battery life by calculating the average between an active battery life and a low
power battery life, as section 11.6 Formulas:Equations 14 to 16 shows that this value will be
approximately 173 h.
7.6 Timing Analysis
The MAV System uses a CC3200 that is a microcontroller that works at 80 MHz when a
program runs in RAM. The MAV System uses a timer to consider the time intervals
established by the health professional and to be able to calculate the heart rate every minute.
To be able to measure time, a calculation is taken into consideration to keep a record of the
seconds the internal timer must be configured with a pre-scalar of 8, and make the timer
count until 10,000,000. This action will simulate that a second has passed.The MAV System
also uses a TMP007 that works with I2C which means that the MCU and the TMP007 will
have a master-slave relationship where the TMP007 will work at the same clock frequency
established by the CC3200 that's 80MHz.
8User Guide
8.1 Installation Guide
The arm band is connected to a data base through a Wi-Fi connection with internet. To
configure an arm band to connect to a Wi-Fi connection, the follow steps are required:
1. Connect the arm band to a computer through an USB cable.
2. Open any serial communication client software. (Ex. Putty).
3. In the host name write COM #, where the # can be obtained by:
a. In Windows, go to Control Panel -> Device Manager.
b. In Device Manager, go to Port (COM &LPT)
c. In the Port list, search the CC3200LP Dual Port (COM #) and take the COM #
4. In the Speed field write 115200.
5. Turn on the band with the on/off switch.
6. In the screen select write 1 and press enter to add a new Wi-Fi connection
a. Insert the Wi-Fi SSID and press enter
b. Insert the Wi-Fi password and press enter
c. Insert 1 if the Wi-Fi security type is WPA or 2 if is OPEN and press enter
7. Power off the band and disconnect the band from the computer.
8.2 Operation Guide
The band will send the data to the data base for default each 15 minutes. If the measure
time of the band is not the desired, then the following steps are necessary to change the
measure time:
1.
2.
3.
4.
In the web page go to band configuration
In the available bands dropdown menu select the band for it band id.
Write the measure time desired in the change measure time field
Press Save button
16
The next time that the band is power on will receive this value as measure time. The arm
band will constantly taking the pulse and temperature value. If one of this values are out of
the range of acceptable values, an alert mode will turn on. The alert mode will send an alert
to the web page, and the LED will go to blink and a buzzer to sound. To turn off the alert
mode, the following step is needed:
1. Press the button that is close to the LED.
2. Automatically the alert mode will exit and continue with the program.
9Conclusion
The final product of this project was able to generate body temperature and heart rate
measuring data. It also had the capability to connect to the internet and transmit and receive
data with a parse database server, in which the system armband receiving protocol establish a
communication between the User interface (which was a web page) and the armband. Once
the system acquired the measurements, it makes a comparison with the average values of a
human body temperature and heart rate, and if the values are not within the established
acceptable range, the system triggers an alert in the room and notifies the database. The
Blood Pressure module of the system was not finished; this module consist of the mix process
between the pressure module and the pulse module. The algorithm to generate the process of
starting this measurement was finished but after thorough testing, the actual reading of
pressure was erroneous, which implicates that more research was needed to be able to use
that pressure component with the CC3200 and finalize the blood pressure measuring process.
Another discovery the team made was that the system needs negative voltage supply to work
with the pressure sensor, something that was not taken into consideration when making the
design.
9.1 Future Works
Currently this version of the system is a prototype, this current competition task are,
taking the body temperature, taking the pulse and taking the blood pressure which consist of a
combination of the pulse and the pressure adding an air cuff. This system has plans for
improvements and add on hardware that cover a larger scan of the body vital signs like:





More Precision with measurements
Since the MAV system is a medical system to be used in hospitals it needs to be as
precise as possible, in this prototype the measurements were accurate but too
approximated for being an medical tool.
Redesign the power supply
A new design for the power supply is needed since it wasn't considered for the
pressure module.
Optimize and Re-design the Pressure sensor module
Since this module was not completed, it is necessary to re-evaluate and design it once
again to be able to fix the communication problems it currently haves with the MCU.
Respiration Rate Module add on
This module will take the body oxygenation that is the last one of the vital signs
needed to complete this system, and it installation in the database.
User Interface Upgrade
Planning of an upgrade of the User Interface web page to have a more manageable,
17

user friendly control over the system bands.
Reporting tool link
This is one of the mayor upgrades that the system will require. This capability enables
the webpage to be link to some powerful reporting tools that when implemented
correctly can generate specific programmed reports to visualize the data represented
in the database on the user interface, and it can even generate each of the reports in an
automated manner for each specific time value put by the programmer. A basic
example is to generate a basic table and graph report of the patients that generated an
alert on a daily basis.
10References
[1] American Heart Association, "Understanding Blood Pressure Readings," 8 April 2014.
[Online]. Available:
http://www.heart.org/HEARTORG/Conditions/HighBloodPressure/AboutHighBloodP
ressure/Understanding-Blood-Pressure-Readings_UCM_301764_Article.jsp.
[Accessed 31 January 2015].
[2] Disabled World, "Blood Pressure Chart," 20 February 2014. [Online]. Available:
http://www.disabled-world.com/artman/publish/bloodpressurechart.shtml.
[Accessed 2 February 2015].
[3] G. Ortiz, "Unidad III: Professional Nurse System FaseEstimado - TemaSignos
Vitales," Mayaguez, 2014.
[4] Embedded Lab, 'Easy Pulse Sensor (Version 1.1) Overview (Part 1) - Embedded Lab', 2013. [Online].
Available:http://embedded-lab.com/blog/?p=7336. [Accessed: 22- May- 2015].
[5] Google Books, 'A Wearable Prototype of Reflective Sensor for Non Invasive Measurement of Heart Rate', 2015.
[Online].
Available: https://books.google.com.pr/books?id=HdUxBgAAQBAJ&pg=PA43&lpg=PA43&dq=2.34+hz&source=bl
&ots=lj9YVNfJC&sig=lS3skEGPY2hwxMXdcaHPkGH9ZIg&hl=en&sa=X&ei=h25IVbebG4KkgwSX2ID4Cw&ved=0CCUQ6AE
wAQ#v=onepage&q&f=false. [Accessed: 22- May- 2015].
[6]G. Patancheru, A Wearable Prototype of Reflective Sensor for Non Invasive Measurement of Heart Rate.
Hamburg, Anchor Academic Publishing 2014, 2014.
[7] ncbi.nlm.nih, 'NCBI', 2015. [Online].
Available: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3394104/pdf/CCR-8-14.pdf. [Accessed: 22- May- 2015].
[8] www.robots.ox.ac.uk, 'robots.ox', 2015. [Online].
Available: http://www.robots.ox.ac.uk/~neil/teaching/lectures/med_elec/notes6.pdf. [Accessed: 22- May- 2015].
[9] www.amperordirect.com, 'amperodirect', 2015. [Online]. Available: https://www.amperordirect.com/pc/helppulse-oximeter/z-what-is-oximeter-plethysmograph.html. [Accessed: 22- May- 2015].
[10] www.vishay.com, 'vishay', 2015. [Online]. Available: http://www.vishay.com/docs/83752/tcrt1000.pdf.
[Accessed: 22- May- 2015].
[11] www.microchip.com, 'LM324 Datasheet', 2015. [Online].
Available: http://ww1.microchip.com/downloads/en/DeviceDoc/21733j.pdf. [Accessed: 22May- 2015].
18
11Appendix
11.1 Figures and Images
Figure 1: Transmissive (left) vs. reflective (right) PPG
19
11.1.1 Block Diagram
Figure 2: Block Diagram Representation of the System
20
11.1.2 State Diagram
Figure 3: System State Diagram
11.1.3 Power Diagrams
Figure 4: Power Schematic View
21
Figure 5: Power Module system view
11.2System Conception
11.2.1Global System View
Figure 6: Global System View
22
11.3 System Schematic
Figure 7: System Schematic
23
11.4User Interface-Level
11.4.1 Arm Band
Figure 8: Arm Band System View
24
11.4.2 Computer Interface:
Figure 9: User interface web page that show a dashboard
Figure 10: User interface web page that show a patient information
25
Figure 11:User interface web page to add a new arm band to the system.
Figure 12: User interface web page to configure an armband and link it to a patient
26
11.5System Flowcharts
11.5.1 Timer ISR
Figure 13: Timer ISR
11.5.2 Pulse ISR
Figure 14: Pulse ISR
27
11.5.3 Pressure Meassurement Algorithm
Figure 15: Pressure Measurement Algorithm
28
11.5.4 Main Software Plan
Figure 16: Main Software Plan
11.5.5 Database ER Diagram
29
Figure17: Database ER Diagram
11.5.6 Button ISR
Figure 18: Button ISR
30
11.5.7 Blink LED and Buzzer Flowchart
Figure 19: Blink LED and Buzzer Flowchart
11.5.8 Alert Flowchart
Figure 20: Alert Flowchart
11.6 Formulas
𝑅=
1
≅ 48.4𝑘Ω
2𝜋(4.7𝜇)(0.7)
31
Equation 1: Resistance for the passive RC HPF
𝑓𝑐 =
1
= .72𝐻𝑧
2𝜋(4.7𝜇)(47𝑘Ω)
Equation 2:Frequency acquired for pulse sensing module
𝑅=
1
≅ 680𝑘
2𝜋(100𝑛)(2.34)
Equation 3: Resistance for low pass filter
𝐷𝐶 𝐺𝑎𝑖𝑛 = 1 +
𝑅2
𝑅1
Equation 4: DC gain Calculation
𝑅1 =
680𝑘
= 6.8𝑘Ω
101 − 1
Equation 5: R1 from DC Calculation
𝐺𝑎𝑖𝑛 = 101 ∗ 101 = 10201
Equation 6: Gain potentiometer modification
𝑅2
3 = 5(
) → 𝑅2 = 6.8𝑘Ω
1.8𝑘Ω + 𝑅2
Equation 7: Pulse Sensor Final Output Voltage
𝐴𝑣 = 1 +
2𝑅
𝑅𝑔𝑎𝑖𝑛
Equation 8: Pressure Amplification
𝑅𝑐 =
5𝑉 − 1.0𝑉 − 3.0𝑉
= 66Ω
15𝑚𝐴
Equation 9: LED Collector Resistance
𝑅𝐵 =
5𝑉 − 1.3𝑉 − 0.4𝑉
= 368Ω
16𝑚𝐴
32
Equation 10: LED Base Resistance
𝐵𝑎𝑡𝑡𝑒𝑟𝑦 𝑙𝑖𝑓𝑒 =
𝐼 𝑠𝑢𝑝𝑝𝑙𝑦 𝑝𝑒𝑟 ℎ
𝐼 𝑡𝑜𝑡𝑎𝑙
Equation 11: Battery life
𝐼 𝑎𝑐𝑡𝑖𝑣𝑒 𝑡𝑜𝑡𝑎𝑙 = 450𝑚𝐴 + 1.5𝑚𝐴 + 2.64𝑚𝐴 = 453𝑚𝐴
Equation 12: total current consumption when active MCU
𝐼 𝑙𝑜𝑤 𝑝𝑜𝑤𝑒𝑟 𝑡𝑜𝑡𝑎𝑙 = 250𝑢𝐴 + 1.5𝑚𝐴 + 2.64𝑚𝐴 = 3.49𝑚𝐴
Equation 13: Total Current Consumption when MCU is in low power mode
𝑎𝑐𝑡𝑖𝑣𝑒 𝑏𝑎𝑡𝑡𝑒𝑟𝑦 𝑙𝑖𝑓𝑒 =
1200𝑚𝐴ℎ
= 3ℎ
453𝑚𝐴
Equation 14: Active Battery Life
𝑙𝑜𝑤 𝑝𝑜𝑤𝑒𝑟 𝑏𝑎𝑡𝑡𝑒𝑟𝑦 𝑙𝑖𝑓𝑒 =
1200𝑚𝐴ℎ
= 343ℎ
3.49𝑚𝐴
Equation 15: Low Power Batter Life
𝑒𝑥𝑝𝑒𝑐𝑡𝑒𝑑 𝑏𝑎𝑡𝑡𝑒𝑟𝑦 𝑙𝑖𝑓𝑒 =
𝑎𝑐𝑡𝑖𝑣𝑒 𝑏𝑎𝑡𝑡𝑒𝑟𝑦 𝑙𝑖𝑓𝑒 + 𝑙𝑜𝑤 𝑝𝑜𝑤𝑒𝑟 𝑏𝑎𝑡𝑡𝑒𝑟 𝑙𝑖𝑓𝑒
= 173 ℎ
2
Equation 16: Expected Battery Life
11.7 Tables
11.7.1 Acceptable Vitals Values
Average pulse values:
Age
Average Value (beats/minute)
Newborn
130
1 year
120
5-8 years
100
10 years
70
33
Teen
75
Adult
80
Old adult
70
Table 1: Average heart rate by age.[1]
Blood Pressure Ranges
Category
Systolic blood pressure (mmHg)
Diastolic blood pressure
(mmHg)
Hypotension
< 90
< 60
Normal
90 - 120
60 - 80
Pre-hypertension
120 - 139
80 - 89
Hypertension I
140 - 159
90 - 99
Hypertension II
> 160
> 100
Table 2: Systolic and Diastolic Blood Pressure Range Table. [2]
Physiological state according to body temperature
Physiological State
Temperature (°C)
Hypothermia
< 36
Average
36 – 38
Pyrexia (Fever)
38 - 41
Hyperpyrexia (Death)
> 41
Table 3: Body Temperature Classification Values [3]
11.7.2 Voltage and Current Consumption Table
Component
Voltage Requirement (V)
Current consumption
CC3200 active
1.6 - 3.3
450mA
CC3200 low power
1.6 - 3.3
250uA
Compressor
5
2.64mA
34
Valve
5
1.5mA
TMP007
3
2uA
Pulse Sensor
3
600uA
Table 4: Voltage and Current Consumption Table
11.7.3 Software Completion Table
Tasks
Percentage Completed
MCU Programming
Wi-Fi Setup
100%
Connection to Parse DB
100%
JSON Parsing
100%
Adding band to system
100%
Syncing band to patient
100%
Sending values to database
100%
Vitals Measuring and Processing
Pulse Rate Interrupt Handling
100%
TMP007 I2C Logic & Interpretation
100%
Blood Pressure Measuring Algorithm
50%
Measure Timing Setup
100%
Alert Handling
100%
Low Power Mode Setup
User Interface Programming
Database Design & Setup
100%
Web Application / DB Integration
100%
Web Application Design
50%
Table 5: Software Completion Table
35
11.7.4 Hardware Completion Table
Tasks
Percentage Completed
Pulse Sensing
100%
Temperature Measuring
100%
Raw Pressure Measuring
90%
Air Cuff Filling
100%
Alert Module
100%
Power Module
70%
Table 6: Hardware Completion Table
11.7.5Work Distribution
Work
Alfredo Cox
Luis Vega
Luis Murphy
Maria Jimenez
x
Power Supply
Module
Temperature Module
x
Wi-Fi Module
x
User Interface
x
x
x
Blood Pressure
Module
x
x
Alert Module
x
Pulse Module
Integrating
Hardware
x
x
Integrating Software
x
x
Database Creation
x
x
x
Table 7: Work Distribution Table
11.8 Bill of Materials
Item
#
Qty
Part #
Unit #
(On
schematic)
Description
Unit
Price
(Sale
Price)
Exit
Price
Supplier
36
1
6
CC3200LAUNCHXL
2
2
TMP007
SEN1
3
3
EasyPulse
Sensor
SEN2
4
2
5
2
6
2
PS1240
BLL515RGBW
-CA
Tactile
On/Off
Switch with
Leads/
Prod. ID
1092
7
1
8
Evaluation development
platform for the CC3200
wireless MCU.
Thermopile sensor that
detects temperature by
absorbing IR waves
emitted. Can be read
directly over I2C.
Mounted circuit that
helps detect the pulse
generated by the body
using
photoplethysmography.
This piezo buzzer is
compact and can
operate with a 3V
square wave.
$29.99
$179.94
Texas
Instruments
$12.50
$25.00
Ada Fruit
$18.50
$55.50
Tindy
$1.50
$3.00
Ada Fruit
Common Anode red,
green, blue LED
$2.00
$4.00
Ada Fruit
S1
Power Switch
$3.95
$7.90
KPM14A
M1
$4.69
$4.69
2
2SMPP03
SEN3
Mini Airpump
OMRON pressure
sensor with analog
output.
Ada Fruit
Ebay/
SmartProto
typing
$7.60
$15.20
9
1
V1
$7.10
6
KOGE Solenoid Valve
Darlington 7 NPN
Transsistor array
$7.10
10
$0.30
$1.80
11
1
KSV05B
ULN2003A
DRG3
Blood
Pressure
Cuff
$10.00
$10.00
12
1
Battery Charger
$6.95
$6.95
13
1
U7
Voltage Regulator
$3.03
$3.03
14
3
MCP73831
MIC52393.3YS
Lithium Ion
Polymer
Battery 3.7v
1200mAh
B1
Battery Power Supply
$9.95
$29.85
15
2
100Ω
Resistor
$0.01
$0.02
16
4
1KΩ
Resistor
$0.01
$0.04
17
4
10KΩ
R3; R4
R1; R5; R7;
R12
R2; R6; R8;
R9
Resistor
$0.01
$0.04
18
2
1.6KΩ
R10; R11
Resistor
$0.01
$0.02
19
3
$11.50
$34.50
20
1
LM741J
TPS5410EP
$7.20
$7.20
Ada Fruit
Radio
Shack
Radio
Shack
Radio
Shack
Radio
Shack
Mouser
Electronics
Texas
Instruments
21
1
0.1uF
$0.29
$0.29
Ada Fruit
U1
LS1
LED1
U3
*** Out of
Schematic
*** Out of
Schematic
U2; U4; U5
Airbag cuff
U4
Single Op Amp IC
1-A Wide Input Range,
Step-Down Converter
C1
Capacitor
DigiKey
Amazon/Ux
cell
Radio
Shack
Ada Fruit
Mouser
Electronics
37
22
1
.01uF
23
2
47uF
24
1
150pF
25
1
2700pF
26
1
28
1
29
3
30
1
31
1
32
2
33
1
34
1
35
1
.056uF
Wisher
WBU-204
Solderless
BreadBoard
Modular IC
Bread
Boards
Sockets
Multipurpos
e PC Board
with 417
holes
40 Premium
Fmale/Male
Extension
Jumper
Wires
29-Range
Digital
Multimeter
Project
Enclosure
3x2x1
Weller
WPS18MP
HIGHPERFORM
ANCE
soldering
iron
Rosin Core
Solder
*** Out of
Schematic
*** Out of
Schematic
*** Out of
Schematic
*** Out of
Schematic
*** Out of
Schematic
Capacitor
$0.29
$0.29
Ada Fruit
Capacitor
$0.29
$0.58
Ada Fruit
Capacitor
$0.29
$0.29
Ada Fruit
Capacitor
$0.29
$0.29
Ada Fruit
$0.29
$0.29
Ada Fruit
*** Out of
Schematic
Capacitor
8.46x5.12x1.22
BreadBoard with
volltageand ground
connections.
$19.97
$19.97
Radio
Shack
*** Out of
Schematic
Small Breadboard
$7.99
$23.97
Radio
Shack
*** Out of
Schematic
Connection tool
$1.99
$1.99
Radio
Shack
Connection tool
Voltage, current, and
continuity measurment
tool.
Recipient for storing the
final product of the
prototype.
$7.95
$7.95
Ada Fruit
$31.99
$63.98
Radio
Shack
$2.09
$2.09
Radio
Shack
Soldering tool
$25.30
$25.30
Soldering tool
$4.79
$4.79
*** Out of
Schematic
*** Out of
Schematic
*** Out of
Schematic
*** Out of
Schematic
*** Out of
Schematic
TOTA
L:
Radio
Shack
Radio
Shack
$547.85
38
Table 8: Bill of Materials
11.9 Team Members
Figure 21: Team picture, from left to right Luis E. Vega, Maria D. Los Angeles, Alfredo Cox, Luis R.
Murphy
39