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Department of Mechanical Engineering
Tainan, Taiwan, R.O.C.
Kun Shan University
May ��
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Mechanical Engineering
Senior Project Research
Chapter I: Pipeline Flow Meter Test Bench Assembly
Chapter II: Peak Flow Meter
Student: Jose Daniel Sandoval Ordoñez
Advisor: Song-Hao Wang
I
II
Contents
Table of Figures ............................................................................................................................ IV
Acknowledgments.......................................................................................................................... V
Chapter I: Pipeline Flow Meter Test Bench Assembly
Abstract I ......................................................................................................................................... 6
1. Introduction ................................................................................................................................. 7
1.1.Background .......................................................................................................................... 7
1.1.1.For oil or natural gas. .................................................................................................. 8
1.1.2.For ammonia. ............................................................................................................... 9
1.1.3.For biofuels (ethanol and biobutanol) ......................................................................... 9
1.1.4.For coal and ore ........................................................................................................... 9
1.1.5.For hydrogen ............................................................................................................. 10
1.1.6.For water .................................................................................................................... 10
1.2.Pipeline Grid Operation ...................................................................................................... 11
1.3.Flow Meter Types .............................................................................................................. 12
2.Materials .................................................................................................................................... 12
3.Assembly.................................................................................................................................... 13
4.Standard Flow Meter.................................................................................................................. 14
4.1.Features .............................................................................................................................. 15
4.2.Short Specifications ............................................................................................................ 15
5.Results ........................................................................................................................................ 16
6.Conclusions ................................................................................................................................ 17
7.References .................................................................................................................................. 18
Chapter II: Peak Flow Meter
Abstract II ..................................................................................................................................... 19
1.Introduction ................................................................................................................................ 20
1.1.Asthma ................................................................................................................................ 20
1.2.History ................................................................................................................................ 21
1.3.What is a Peak Flow Meter? ............................................................................................... 22
1.4.Forced Expiratory Volume ................................................................................................. 24
1.5.Lung Volumes .................................................................................................................... 25
III
1.6.Definitions .......................................................................................................................... 26
2.Technologies Used ..................................................................................................................... 27
2.1.Rapid Prototyping ............................................................................................................... 27
2.1.1.The RP (Rapid Prototyping) process ......................................................................... 28
2.1.2.Benefits of rapid prototyping .................................................................................... 29
2.2.3D Drawing or CAD .......................................................................................................... 31
2.2.1.Design Process .......................................................................................................... 32
3.Equipment .................................................................................................................................. 33
3.1.Hardware ............................................................................................................................ 33
3.1.1.FDM machine ............................................................................................................ 34
3.2.Software .............................................................................................................................. 35
3.2.1.Solid Works ............................................................................................................... 35
4.Peak Flow Meter Design ............................................................................................................ 37
4.1.Peak Flow Meter conceptualization ................................................................................... 37
4.2.Peak Flow Meter Prototype01 ............................................................................................ 38
4.3.Peak Flow Meter Prototype02 ............................................................................................ 39
4.4.Peak Flow Meter Prototype03 Design ................................................................................ 40
4.4.1.Peak Flow Meter Prototype 03 Version 2 ................................................................. 43
4.4.2.Design of tester for the coil of the Peak Flow Meter Prototype03 ............................ 44
4.4.3.Tests and Results ....................................................................................................... 46
4.4.4.Peak Flow Meter Prototype 03 Version 3 ................................................................. 47
5.Future Enhancements ................................................................................................................. 49
6.Conclusions ................................................................................................................................ 49
7.References .................................................................................................................................. 50
IV
Table of Figures
Figure 1: Pipeline Grid Operation................................................................................................. 11
Figure 2: Test Bench Assembly .................................................................................................... 13
Figure 3: Flow Rate – Tokyo Keiso Commercial flow meter vs. our flow meter ........................ 16
Figure 4: Asthma Pathology Illustration ....................................................................................... 20
Figure 5: Peak Flow Meter ........................................................................................................... 23
Figure 6: Normal Values of PEF .................................................................................................. 24
Figure 7: Fused Deposition Modeling Process ............................................................................. 31
Figure 8: Iterative Design Process ................................................................................................ 33
Figure 9: Dimension BST Printer ................................................................................................. 34
Figure 10: Peak Flow Meter Concept design ................................................................................ 38
Figure 11: Peak Flow Meter Prototype 01 .................................................................................... 39
Figure 12: Peak Flow Meter Prototype 02 .................................................................................... 40
Figure 13: Peak Flow Meter Prototype 03 .................................................................................... 41
Figure 14: PFM Prototype 03 views ............................................................................................. 42
Figure 15: PFM Prototype 03 V2 ................................................................................................. 43
Figure 16: Tester exploded view................................................................................................... 45
Figure 17: Peak Flow Meter P03 V3 ............................................................................................ 48
Figure 18: Peak Flow Meter P03 V3 Dimensions ........................................................................ 48
V
Acknowledgment
First of all I would like to thank God for giving me the knowledge and strength to pursue this
research and an education abroad; without Him I wouldn’t be where I am now neither would
have I been able to accomplish my goals and objectives.
As equally important I would like to express my sincere and deepest thanks to The Republic of
China and its people for giving me the incredibly important opportunity of letting me in their
home and receiving me with their arms open to study and learn so much about their culture and
knowledge.
Secondly I would like to acknowledge ICDF for financing my studies in Taiwan and allowing
me to pursue my dream of obtaining a professional degree in a country so developed and
advanced, for giving me the opportunity of embracing another culture and of learning everything
that now makes me a better person and a better professional.
During the length of the four years that I have been able to live in this beautiful place Kun Shan
University has been my loving home and family, without its caring people it would have been
impossible to me to learn the vast amount of knowledge that I have now; I want to thank
especially the Department Of Mechanical Engineering and all the department teachers and staff
for sharing their huge wisdom and affection with me; the International Office for guiding me
during these four years and showing me the path to follow making my stay easier; and finally the
Military Office for giving me a house and a place to live in the school dorms and managing the
order and discipline, which I am sure is not an easy task.
Special thanks are deeply granted to Dr. Song-Hao Wang, my senior project advisor, for his
guidance, patience and the precious time he bestowed upon me as his student and friend; to
professor Shao-Shu Chu, my class advisor; and to my loved family for their unconditional
support, love, and counsels, for the sacrifice they made of letting me go at such a young age, and
for the patience they have had during this whole time.
And last but not least to my dear friends and classmates for their support, their unconditional
friendship and their selfless love towards me.
Chapter I: Pipeline Flow meter Test Bench Assembly
Kun Shan University
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Abstract I
The following pages describe the creation of a
test bench system with each material and
parameters used; trying to illustrate how this
project was born as an idea and the purpose
behind it in the clearest way possible is one of
the objectives of this thesis.
As we all know there lies an intrinsic and
obvious importance in testing new products
and their working principles, this helps
designers to review their work and improve
some of the mistakes done during the
construction process.
These tests are not only required to see if the
product does work or not, but most importantly
these investigations are performed to calibrate
and give a high measurement capacity and
accuracy to the new-born devise.
This is where the most profound target and
goal of this work rests, to make this calibration
task easier and more practical in a simple
manner with low costs and every-day easy-to-
obtain materials.
Chapter I: Pipeline Flow meter Test Bench Assembly
Kun Shan University
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1. Introduction
Designing a new product is not one of the easiest and simplest procedures a person can intend it
involves a lot of thinking, designing, researching, and above all testing; testing your product is
one of the most critical and important things you have to do to achieve a production level of this
new design; and since testing involves calibrating sometimes we need to come up with new test
bench designs of our own, specially made for the product we intend to create.
The purpose of this test bench is exactly that, to test and calibrate the new flow meter design that
we have come up with and to make it easier for the tester to fine-tune the new equipment, this
assembly is pretty simple and does not require too much time to achieve therefore saving time in
the whole product finishing.
1.1. Background
First we need to understand the different outlines of pipelines and how the flow meters are
implemented in them, the different types of flow meters and how they work.
Pipeline transport is the transportation of goods through a pipe. Most commonly, liquids and
gases are sent, but pneumatic tubes that transport solid capsules using compressed air are also
used.
Chapter I: Pipeline Flow meter Test Bench Assembly
Kun Shan University
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As for gases and liquids, any chemically stable substance can be sent through a pipeline.
Therefore sewage, slurry, water, or even beer pipelines exist; but arguably the most valuable are
those transporting fuels: oil (oleoduct), natural gas (gas grid), and biofuels.
Dmitri Mendeleev first suggested using a pipe for transporting petroleum in 1863. [1]
These pipelines are classified depending on the fluid they transport:
1. For oil or natural gas
2. For ammonia
3. For biofuels (ethanol and biobutanol)
4. For coal and ore
5. For hydrogen
6. For water
7. For beverages
7.1. For beer
8. For other uses
We will focus on the pipeline used for water transport, since our flow meter is designed to use
with water, although we will need to know the basic concept and importance of the other types of
pipes thus we will see a little about the rest of their uses.
1.1.1. For oil or natural gas.
Oil pipelines are made from steel or plastic tubes with inner diameter typically from 4 to 48
inches (100 to 1,200 mm). Most pipelines are typically buried at a depth of about 3 to 6 feet
(0.91 to 1.8 m). The oil is kept in motion by pump stations along the pipeline, and usually flows
at speed of about 1 to 6 metres per second (3.3 to 20 ft/s).
Chapter I: Pipeline Flow meter Test Bench Assembly
Kun Shan University
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1.1.2. For ammonia.
Highly-toxic ammonia is theoretically the most dangerous substance to be transported through
long-distance pipelines. However, practically incidents on ammonia-transporting lines are
uncommon - unlike on industrial ammonia-processing equipment.
1.1.3. For biofuels (ethanol and biobutanol)
Pipelines have been used for transportation of ethanol in Brazil, and there are several ethanol
pipeline projects in Brazil and the United States. Main problems related to the shipment of
ethanol by pipeline are its high oxygen content, which makes it corrosive, and absorption of
water and impurities in pipelines, which is not a problem with oil and natural gas. [2][3].
1.1.4. For coal and ore
Slurry pipelines are sometimes used to transport coal or ore from mines. The material to be
transported is closely mixed with water before being introduced to the pipeline; at the far end,
the material must be dried.
Chapter I: Pipeline Flow meter Test Bench Assembly
Kun Shan University
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1.1.5. For hydrogen
Hydrogen pipeline transport is a transportation of hydrogen through a pipe as part of the
hydrogen infrastructure. Hydrogen pipeline transport is used to connect the point of hydrogen
production or delivery of hydrogen with the point of demand, with transport costs similar to
CNG,[4] the technology is proven. [5]
1.1.6. For water
Two millennia ago the ancient Romans made use of large aqueducts to transport water from
higher elevations by building the aqueducts in graduated segments that allowed gravity to push
the water along until it reached its destination. Hundreds of these were built throughout Europe
and elsewhere, and along with flour mills were considered the lifeline of the Roman Empire. The
ancient Chinese also made use of channels and pipe systems for public works. The famous Han
Dynasty court eunuch Zhang Rang (d. 189 AD) once ordered the engineer Bi Lan to construct a
series of square-pallet chain pumps outside the capital city of Luoyang. [6]
Pipelines are useful for transporting water for drinking or irrigation over long distances when it
needs to move over hills, or where canals or channels are poor choices due to considerations of
evaporation, pollution, or environmental impact.
Chapter I: Pipeline Flow meter Test Bench Assembly
Kun Shan University
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1.2. Pipeline Grid Operation
The aqueduct has to be monitored and measured to control its pressure, flow temperature, etc.
these instrumentations besides being used for data gathering are also used as communication
devices, that is when our flow gage is used. How is this going to work? Basically what the flow
meter does is that measures the amounts of liters per second at which the water is running, then
this data is sent to a remote receiver. The field Instrumentation includes flow, pressure and
temperature gauges/transmitters, and other devices to measure the relevant data required. These
instruments are installed along the pipeline on some specific locations, such as injection or
delivery stations, pump stations (liquid pipelines) or compressor stations (gas pipelines), and
block valve stations.
The information measured by these field instruments is then gathered in local Remote Terminal
Units (RTU) that transfer the field data to a central location in real time using communication
systems, such as satellite channels, microwave links, or cellular phone connections.
Figure 1: Pipeline Grid Operation
Chapter I: Pipeline Flow meter Test Bench Assembly
Kun Shan University
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1.3. Flow Meter Types
There are five main classifications of flow meters based on the principle governing their
functionality, these are: differential pressure, positive displacement, velocity, mass, open-channel.
These categories have their own sub categories with each flow meter functioning in a slightly
different way than its predecessor:
Differential
pressure
Positive
displacement
Velocity Mass Open-channel
Orifice plate
Venturi tube
Flow tube
Flow nozzle
Pitot tube
Elbow tap
Target
Reciprocating piston
Oval gear
Nutating disk
Rotary vane
Turbine
Vortex shedding
Swirl
Electromagnetic
Ultrasonic, Doppler
Ultrasonic, Transit-
time
Coriolis
Thermal
Weir
Flume
2. Materials
• Bolts
• L-brackets
• L shape aluminum Profiles
• I shape aluminum Profiles
• Nuts
• 1/2” PVC pipe
• 1/2” PVC tap or valves
• 1/2” PVC elbows
• Working flow meter
• Submersible Pump
Chapter I: Pipeline Flow meter Test Bench Assembly
Kun Shan University
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3. Assembly
First we need to connect all the PVC tubes in a trident way, two taps on the left and right set of
tubes and on the center set of tubes we need to connect the working and already calibrated flow
meter, this flow meter is going to help us fine-tune the other two meters that are connected at the
end of the right and left set of tubes, the faucets are mounted on the right and left tube to control
the amount of water that flows through each meter, and the pump is going to be connected at the
beginning of the whole pipeline which is at the center tube before the working flow meter.
This whole assembly is going to be mounted in our previously built stand, constructed from the I
shape aluminum profiles and the L shape profiles.
In this picture we have a complete illustration of
the trident form of our test bench assembly the
main pipe as you can see is in the center coming
out of the submersible pump installed on the
beginning of the circuit, after this we can find (in
the center pipe) the control flow meter which is the
one we are going to use to calibrate the other two
flow meters; the red valves regulating the flow of
water can also be appreciated from this picture.
(1) Flow Meters, (2) Valves, (3) Control Flow
Meter, (4) Submersible pump.
2 2
3
1
4
1
Figure 2: Test Bench Assembly
Chapter I: Pipeline Flow meter Test Bench Assembly
Kun Shan University
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The water in the system is pumped from the bottom of the tank with the submersible pump after
that it reaches control flow meter in which we read the real flow rate in liters per minute after the
recording of this value is made then the water flows through both of the flow meters attached at
the end of the circuit; the calibration system is then connected to this two flow meters. This is the
basic working principle of the test bench.
The accuracy is a defining factor for the correct calibration of the flow meter, “Calibration is a
comparison between measurements – one of known magnitude or correctness made or set with
one device and another measurement made in as similar a way as possible with a second device.
The device with the known or assigned correctness is called the standard. The second device is
the unit under test, test instrument, or any of several other names for the device being calibrated.”
[7]
This is the main reason why the control flow meter or the standard flow meter accuracy has to be
high, in this work the flow meter accuracy was expressed in percent or actual flow rate as:
% of Rate Accuracy = +- (Flow uncertainty / Instantaneous Flow Rate) x 100
At a maximum flow rate this percentage of accuracy was estimated to be +-2.5% since,
• Flow Uncertainty was equal to 1.15 L
• Instantaneous Flow Rate was equal to 45.5 L/min
In general, the lower the loads a flow meter has, the more accurate it is. In this experiment it was
observed that a constant low load was enough to obtain a constant and accurate flow rate within
a minimum of five liters per minute.
4. Standard Flow Meter
The control Flow Meter used for this project was a Tokyo Keiso Flow Meter, Model W-116 it’s
a Mini-Wheel Flowmeter that measures flow rate of water and water equivalent viscosity liquids
by counting the number of the built-in wheel's rotation.
Chapter I: Pipeline Flow meter Test Bench Assembly
Kun Shan University
15 4.1. Features
• Possible to monitor the flow directly
• Easy reassembling and cleaning
• Excellent linearity of voltage output
• Compact in shape due to precision casting
• CE marking
4.2. Short Specifications
Measuring fluid Cooling water and various liquids
(viscosity: less than 2mPa·s Equivalent to
water, and liquid not corroding wetted parts
materials)
Flow Range Maximum 10 to 100 L/min
Minimum 0.6 to 3 L/min
Fluid Temperature 0 to 50° C (without freezing)
Material Body: SCS 14
Wheel: Nylon 12
Shaft: HC-276
O-ring: NBR
Process Connection Rc ¼, Rc 3/8, Rc ¾ thread
Accuracy ±5% F.S.
Output TW-11□: NPN Open collector pulse
( Unscaled pulse )
TW-12□: DC0 to 5V
Power Supply TW-11□: DC12 to 24V
TW-12□: DC12V±10%
Chapter I: Pipeline Flow meter Test Bench Assembly
Kun Shan University
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5. Results
We were able to success with the calibration not only by obtaining a good accuracy in the peak
flow meter but also by maintaining this accuracy throughout the different ranges of flow lectures,
the accuracy is kept constant at a flow rate from 5 to 20 L/min and from 37 to 45.5 L/min.
The following figure shows the comparison of accuracies between the Toyo Keiso commercial
flow meter and our flow meter.
Figure 3: Flow Rate – Tokyo Keiso Commercial flow meter vs. our flow meter
The folowing table presents the relationship between flow rate and power generated for
efficiency assessment.
Flow Rate L/min DC Power Vol DC Power mA DC Power W
5.00 2.50 7.00 0.02
10.00 5.30 25.00 0.13
20.00 10.00 44.00 0.44
30.00 16.00 68.00 1.09
40.00 20.00 100.00 2.00
45.00 20.80 115.00 2.39
Chapter I: Pipeline Flow meter Test Bench Assembly
Kun Shan University
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6. Conclusions
Since the beginning of the project our goal was to facilitate and help to the total calibration of the
new flow meters, this could not be made by only one individual so the task to build a frame for
the test bench came to us; with a lot of dedication we tried to make the test bench the most
accurate and practical that we could.
The calibration of all the flow meters that were tested in our test bench were conducted
successfully and satisfactorily thus confirming the correct performance of the system.
As always everything can be perfected and this project is not the exception, further modifications
can include a better control flow meter (standard flow meter)with more precision to achieve an
even higher degree of accuracy and the modification required on the flow meters that are
required to be calibrated to make them even more exact.
Chapter I: Pipeline Flow meter Test Bench Assembly
Kun Shan University
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7. References
[1] “Pipeline Transport” article http://en.wikipedia.org/wiki/Pipeline_transport
[2] James MacPherson (2007-11-18). "Ethanol makers consider coast-to-coast pipeline"
[3] USA Today. Retrieved 2008-08-23.; John Whims (August 2002) (PDF). Pipeline
Considerations for Ethanol. Kansas State University. Retrieved 2008-08-23.
[4] Compressorless Hydrogen Transmission Pipelines
http://www.leightyfoundation.org/files/WHEC16-Lyon/WHEC16-Ref022.pdf
[5] DOE Hydrogen Pipeline Working Group Workshop
http://www1.eere.energy.gov/hydrogenandfuelcells/pdfs/hpwgw_airprod_remp.pdf.
[6] Needham, Joseph (1986). Science and Civilization in China: Volume 4, Part 2. Taipei: Caves
Books Ltd. Page 33.
[7] “Calibration” article http://en.wikipedia.org/wiki/Calibrati
Chapter II: Peak Flow Meter
Kun Shan University
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Abstract II
As we know Asthma has been a serious
problematic and mortal disease since ancient
times; it is known that asthma existed in
ancient Egyptian times, and there is some
evidence that asthma has been around even
before that.
A lot of people suffer from this disease; in
1995 statistics show that 71 out of 10,000
people were emergency hospitalized and
treated; even more alarming is the mortality
rate, this being 2 persons out of 100,000
although it sounds a little low it is still a
number that can be reduced with proper control.
This is the main purpose of the development of
a reliable yet inexpensive Peak Flow Meter,
since asthma does not discriminate between
social classes our goal is to provide an
inexpensive control tool, dependable, and
accurate whit which households and doctors
can save more lives.
The following pages describe the design,
construction, working principle, specifications
and overall development and changes that have
been and will be implemented in this prototype
for further study and a possible introduction on
the market.
Chapter II: Peak Flow Meter
Kun Shan University
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1. Introduction
1.1. Asthma
Asthma is an inflammatory disorder of the airways, which causes attacks of wheezing, shortness
of breath, chest tightness, and coughing.
Asthma is caused by inflammation in the airways. When an asthma attack occurs, the muscles
surrounding the airways become tight and the lining of the air passages swell. This reduces the
amount of air that can pass by, and can lead to wheezing sound. Asthma may also be classified as
atopic (extrinsic) or non-atopic (intrinsic). [1]
Figure 4: Asthma Pathology Illustration
Chapter II: Peak Flow Meter
Kun Shan University
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Most people with asthma have attacks separated by symptom-free periods. Some people have
long-term shortness of breath with episodes of increased shortness of breath. Either wheezing or
a cough may be the main symptom. Asthma attacks can last for minutes to days, and can become
dangerous if the airflow is severely restricted.
It is thought to be caused by a combination of genetic and environmental factors. [2] Treatment
of acute symptoms is usually with an inhaled short-acting beta-2 agonist (such as salbutamol). [3]
If the patient takes control of his/her asthma, he/she can keep living the life they want. If not,
they may miss many activities they enjoy. The symptoms can become more dangerous and
require visit to hospital emergency rooms. Left uncontrolled, asthma may cause permanent
damage.
The first step in taking control of asthma is having a plan. The plan should cover how you will
do the day-to-day activities that keep your asthma under control:
• Check: Learn to use a simple device called Peak Flow Meter in order to measure the
breathing regularly.
• Take your medications
• Avoid triggers such as allergens and irritants, animals hair, dust, etc.
• Exercise
1.2. History
The measurement of peak expiratory flow was pioneered by Dr. Martin Wright, Who produced
the first meter specifically designed to measure this index of lung function.
Chapter II: Peak Flow Meter
Kun Shan University
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Since the original design of instrument was introduced in the late 1950s, and the subsequent
development of a more portable, lower cost version (the ‘Mini-Wright’ peak flow meter), other
design and copies have become available across the world. [4]
1.3. What is a Peak Flow Meter?
A peak flow meter is a small, hand-held device used to monitor a person's ability to breathe out
air. It measures the airflow through the bronchi and thus the degree of obstruction in the airways.
[5]
A peak flow meter measures the patient’ Peak Expiratory Flow Rate (PEFR or PEF) this means
the maximum speed of exhalation. When the patient is well the peak flow meter readings are
high, on the other hand they appear low when the airways are constricted.
The basic structure of a Peak Flow Meter consists of a tube with a sliding indicator that moves
along a scale marked in liters per minute. Generally the numbers marked on the tube range from
50 to 800 (Peak Flow Meters with a smaller scale range are used for pediatrics). To use a peak
flow meter you simply take a deep breath, put the peak flow meter in your mouth, and blow as
hard and as fast as you can. It is not necessary to exhale completely since this can cause
coughing and a bad reading.
Chapter II: Peak Flow Meter
Kun Shan University
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Figure 5: Peak Flow Meter
The measurement values will be based on a person’s gender, age and height. The best of three
readings is used as the recorded value of the Peak Expiratory Flow Rate. It may be plotted out on
graph paper charts together with a record of symptoms or using peak flow-charting software.
Peak flow readings are often classified into 3 zones of measurement according to the American
Lung Association: green, yellow and red.
Zone Reading Description
Green zone
80 to 100 percent of the usual or normal peak flow readings are clear.
Indicates that the asthma is under good control.
Yellow zone
50 to 79 percent. Indicates caution. It may mean respiratory airways are narrowing.
Red zone Less than 50 percent. Indicates a medical emergency. Severe airway narrowing may be occurring and immediate action needs to be taken.
Chapter II: Peak Flow Meter
Kun Shan University
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Figure 6: Normal Values of PEF
1.4. Forced Expiratory Volume
The Force Expiratory Volume (FEVT) is the volume of gas expired during a given interval (t)
from the beginning of the FVC maneuver. The Forced Expiratory Volume is normally stated in
liters (FEVT), and T is expressed in seconds. Of the various FEVT measurements the FEV1 is
the most widely used.
Chapter II: Peak Flow Meter
Kun Shan University
25
Significance:
Decreased FEVT values are common in both obstructive and restrictive patterns. Distinction
between obstructive and restrictive causes of reduced FEVT is made by relating the FEVT to the
VC as the FEVT/FVC ratio , and to other flow measurements. In obstructive patterns the FVC
may be normal and the FEVT reduced; in restrictive patterns the FVC and the FEVT are
proportionally decreased.
The FEV1 and the FEV1/FVC ratio are the most widely used and best standardized indices of
obstructive disease and is used for assessment of response to bronchodilators, inhalation
challenge studies and for detection of exercise-induced bronchospasm.
1.5. Lung Volumes
Lung volumes and lung capacities refer to the volume of air associated with different phases of
the respiratory cycle. Lung volumes are directly measured. Lung capacities are inferred from
lung volumes.
The average total lung capacity of an adult human male is about 6 litres of air, but only a small
amount of this capacity is used during normal breathing.
Since lung volumes are variable from one person to another there are some factors that affect
lung volumes; some can be controlled and some cannot. Lung volumes vary with different
people as follows:
Larger volumes Smaller volumes
Taller people Smaller people
Non-smokers Smokers
People who live at high altitudes People who live at low altitudes
Chapter II: Peak Flow Meter
Kun Shan University
26
The amount of air that you move in and out of your lungs while breathing normally is called
Tidal Volume (VT). This amount of air provides enough oxygen for a person who is resting, and
the maximum amount of air moved in and out of the lungs is called Vital Capacity.
1.6. Definitions
To better comprehend the importance and how the Peak Flow Meter operates, we must state
some significant definitions that are given in the field of spirometry, these are:
Forced Vital Capacity (FVC) Forced vital capacity (FVC) is the volume of air that can forcibly
be blown out after full inspiration, measured in liters. FVC is the most basic maneuver in
spirometry tests.
Forced Expiratory Volume in 1 second (FEV1) is the volume of air that can forcibly be blown
out in one second, after full inspiration. Average values for FEV1 in healthy people depend
mainly on sex and age, values of between 80% and 120% of the average value are considered
normal. [6]
FEV1/FVC ratio (FEV1%) is the ratio of FEV1 to FVC. In healthy adults this should be
approximately 75–80%. Usually decreased in obstructive airways and is independent of the
relative values of FVC and FEV1.
Peak Expiratory Flow (PEF) usually decreased in obstructive airways and is independent of the
relative values of FVC and FEV1.
Tidal volume (TV) is the volume of air inspired or expired in a single breath at rest.
Total Lung Capacity (TLC) is the maximum volume of air present in the lungs.
Chapter II: Peak Flow Meter
Kun Shan University
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Besides the factors related to human nature, we also have diseases we must take into
consideration that affect the overall lung volumes. We can group them into Obstructive lung
disease and Restrictive lung disease.
Obstructive lung disease is a category of respiratory diseases characterized by airway
obstruction. As an example we have the following: asthma, emphysema, bronchitis, chronic
obstructing pulmonary disease.
Restrictive lung disease the restrictive lung diseases are a category of extra pulmonary, pleural,
or parenchymal respiratory diseases that restrict lung expansion, resulting in a decreased lung
volume, an increased work of breathing, and inadequate ventilation and/or oxygenation.
Pulmonary function test demonstrates a decrease in the forced vital capacity.
As seen, the FEV1/FVC ratio is considerably decreased when the patient suffers from obstructive
or restrictive lung disease, so the FEV1 is by far the most frequently used index for assessing
airway obstruction, bronchoconstriction or bronchodilatation. [7]
2. Technologies Used
• Rapid Prototyping
• 3D drawing or CAD
2.1. Rapid Prototyping
Rapid prototyping can be defined as a group of techniques used to quickly fabricate a scale
model of a physical part or assembly using three-dimensional computer aided design (CAD) data.
[8]
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Construction of the part or assembly is usually mostly done using 3D printing technology. The
first techniques for rapid prototyping became available in the late 1980s and were used to
produce models and prototype parts. Today, they are used for a much wider range of applications
and are even used to manufacture production-quality parts in relatively small numbers. Some
sculptors use the technology to produce exhibitions. [9]
Rapid Prototyping has also been referred to as solid free-form manufacturing; computer
automated manufacturing, and layered manufacturing. RP has obvious use as a vehicle for
visualization. In addition, RP models can be used for testing, such as when an airfoil shape is put
into a wind tunnel. RP models can be used to create male models for tooling, such as silicone
rubber molds and investment casts. In some cases, the RP part can be the final part, but typically
the RP material is not strong or accurate enough.
2.1.1. The RP (Rapid Prototyping) process
The basic methodology for all current rapid prototyping techniques can be summarized as
follows:
• To begin the rapid prototyping process, a virtual design is created with CAD, computer
aided design, or with another animation modeling software, then this design is converted
to STL format; the resolution can be set to minimize stair stepping.
• This virtual design will be the starting point to create the model or prototype.
• The image will be the basis for the final protocol that is developed.
• The RP machine processes the .STL file by creating sliced layers of the model.
• The first layer of the physical model is created. The model is then lowered by the
thickness of the next layer, and the process is repeated until completion of the model.
In other words rapid prototyping takes the image and begins applying very thin layers of powder,
liquid, or sheet material until the final product has been created. The model takes shape as cross
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sections of the materials begin to take form into the intended design. The cross sections are
fused together once they are complete. The completed physical model and the virtual model
should be nearly identical at the end of the process. At the end of this whole process the
completed piece is removed the bases cut off and the surfaces cleaned and polished.
2.1.2. Benefits of rapid prototyping
• It allows the user to create the finished product very quickly. If these prototypes had to
be created manually it would take anywhere from several hours to possibly several days.
• When rapid prototyping is used a project can be completed in just a few hours. The exact
time it takes varies depending on the specific type of machine that is used and how big
the prototype will be in its final form.
• When a solid freeform fabrication technique is used, two different materials will be used.
One material is used to create the actual prototype of model and the other is used as
support so that the piece can be configured accurately. This technique makes the removal
of the support material easier, allowing the piece to be finished even faster.
• While it is less expensive to create the models using injection molding if you are creating
a large amount of the same items, when the goal is to complete only a few parts then the
additive fabrication can provide a significant cost saving.
The research and development throughout the course of these years since the introduction of the
RP technology and the use of additive manufacturing technology on the 1980s has allowed the
industry and developers of new products to implement new schemes and concepts in the field of
Rapid Prototyping, these concepts have evolved to the point of reaching the production line
which has allowed in its own terms the use of new and more advanced technologies and forms of
RP; each and one of these forms uses different materials, different components, and also each of
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them is used for different purposes than its predecessor or competitors; this huge diversity of
machines opens field to a variety of manufacturing and construction times some of this times
lasting from a few minutes to a couple of days (depending on the complexity of the model being
created by these machines), usually this times range around a common average of a few hours.
A wide division of these technologies can be made taking into account different parameters but
for reasons of efficiency we are going to focus in the most common areas of these technologies;
the following table illustrates the different types of rapid prototyping and the materials each one
uses:
Prototyping Technologies Base Material
Stereolithography (SLA) Photopolymer
Selective Laser Sintering (SLS) Thermoplastic, metal powders
Fused Deposition Modeling (FDM) Thermoplastic, Eutectic metals
Laminated Object Manufacturing (LOM) Paper
3D Printing (3DP) Various materials
Electron Beam Melting (EBM) Titanium alloys
The technology used to create the models for the prototype developed in this project is FDM or
Fused Deposition Modeling, is a solid-based rapid prototyping method that extrudes material,
layer-by-layer, to build a model. The system consists of a build platform, extrusion nozzle, and
control system.
The build material, a production quality thermoplastic, is melted and then extruded through a
specially designed head onto a platform to create a two-dimensional cross section of the model.
The cross section quickly solidifies, and the platform descends where the next layer is extruded
upon the previous layer. This continues until the model is complete, where it is then removed
from the build chamber and cleaned for study or shipping.
The layer thickness and vertical dimensional accuracy of the machine is determined by the
extruder die diameter, which ranges from 0.013 to 0.005 inches. In the X-Y plane, 0.001 inch
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resolution is achievable. A range of materials are available including ABS, polyamide,
polycarbonate, polyethylene, polypropylene, and investment casting wax.
Figure 7: Fused Deposition Modeling Process
2.2. 3D Drawing or CAD
Computer Aided Design is the use of computer systems to assist in the creation, modification,
analysis, or optimization of a design [10]. Beginning in the 1980s computer-aided design
programs reduced the need of draftsmen significantly, especially in small to mid-sized
companies. Since these first steps the CAD techniques have widely evolved and with this
evolution a diversity of software products were born; some of these platforms are, Pro/E, CATIA,
Solid Works, Solid Edge and Inventor; just to mention some.
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The designs or models that these technologies help us analyze are also known as parametric
models or Parametric Sketching. However parametric sketching and drawing are not the same; A
sketch is a collection of geometry (lines, points, and arcs) coupled with relationships (parameters,
equations, dimensions, sketch constraints, and construction geometry) laid out in a 2D format.
A sketch has to be more defined understandable and have a degree of completion from which a
manufacturer can produce an accurate reproduction of the object that is being targeted with the
design, all the geometric elements contained in the drawing have to be related to each other to
reflect the sketch intent. These drafts are used to define 3D geometry, which is then projected to
2D for final prints.
2.2.1. Design Process
Design is the act of devising an original solution to a problem by a combination of principles,
resources and products in design. Design process is the pattern of activities that is followed by
the designer in arriving at the solution of a technological problem.
The design process is an iterative procedure. A preliminary design is made based on the available
information and is improved upon as more and more information is generated. There have been
several attempts to provide a formal description of the stages or elements of the design process.
The design progresses in a step-by-step manner from some statement of need through
identification of the problem, a research for solution and development of the chosen solution to
trial production and use. These descriptions of design are known as models of the design process,
the following picture shows how a basic design process takes place, as it was said above it is an
iterative process in which continuous revision and constant changes are made as new information
on the prototype becomes available.
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Figure 8: Iterative Design Process
3. Equipment
3.1. Hardware
• Rapid Prototyping FDM Machine
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3.1.1. FDM machine
The machine used to construct and print the models for the assemble of our product was a
Dimension BST machine.
Figure 9: Dimension BST Printer
The current specifications for this machine are:
• Starting price: $24,900
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• Model Material: ABSplus in ivory, white, black, red, olive green, nectarine, fluorescent
yellow, blue or gray.
• Support Material: Breakaway Support Technology (BST)
• Build Size: 254 x 254 x 305 mm
• Layer Thickness: .254 mm (.010 in.) or .33 mm. (.013 in.) of precisely deposited
ABSplus model and support material.
• Workstation Compatibility: Windows® XP / Windows Vista® / Windows® 7
• Network connectivity: Ethernet TCP/IP 10/100Base-T
• Size and Weight: 838 x 737 x 1143 mm (33 x 29 x 45 in.) 148 kg (326 lbs.)
• Power Requirements: 110-120 VAC, 60 Hz, minimum15A dedicated circuit; or 220-240
VAC, 50/60 Hz, minimum 7A dedicated circuit.
3.2. Software
• Solid Works 2010
3.2.1. Solid Works
SolidWorks is a 3D mechanical CAD (computer-aided design) program that runs on Microsoft
Windows and is being developed by Dassault Systèmes SolidWorks Corp., a subsidiary of
Dassault Systèmes, S. A. (Vélizy, France). SolidWorks is currently used by over 1.3 million
engineers and designers at more than 130,000 companies worldwide [11]. SolidWorks
Corporation was founded in December 1993 by Jon Hirschtick with headquarters in Waltham,
Massachusetts, USA, [12][13] who recruited a team of engineers to build a company that
developed 3D CAD software that was easy-to-use, affordable and available on the Windows
desktop, with its headquarters at Concord, Massachusetts, and released its first product,
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SolidWorks 95, in 1995, later in 1997 SolidWorks Corporation was acquired by the company
known as Dassault Systèmes, best known for its CATIA CAD software.
Since then Solid Works corporation has launched several new versions of its leading software
improving in each new release the whole software making it more user friendly, more reliable,
adding new features as simulation and libraries with tons of standardized mechanical parts; just
to name a few of the more notorious advancements on this complete solution. But Solid Works
isn’t the company’s only product; they have produced a collaboration tool called eDrawing and
software focusing entirely in a 2D sketching and modeling named DraftSight.
As I mentioned before the version of the software used in this project is Solid Works 2010, the
top enhancements for this version provide improvements to existing products and innovative new
functionality, some of the new features present in this version are:
• User Interface
o Mouse Gesture Support
• Fundamentals
o Reference Planes
• Assemblies
o Assembly visualization
o Mirror components
o Virtual components
• Configurations
o Configuration Publisher
o Modify Configurations
• Drawing and Detail
o Rapid Dimension
o Dimension Palette
o Drawing views of multibody parts
• Enterprise PDM
o Enterprise PDM and toolbox integration
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• Motion Studies
o Event Based Motion Study
• Parts and Features
o Move face Features
• Routing
o Manufacture-style flattening
4. Peak Flow Meter Design
The Design of the Casing for the Peak Flow Meter was based on its utility, components,
ergonomics and size. The process started with several sketches aiming to an appealing and
serious shape, due to its future use in the health sector. There were three prototypes developed
for the further progress and testing of the Peak Flow Meter, these two prototypes were printed
using Rapid Prototyping (RP).
4.1. Peak Flow Meter conceptualization
In the early conceptualization of the PFM, the main components where established, such as; the
LCD Screen, Electronic components PCB, Battery and Generator for a better approach and
layout of the main components. Respecting the layout of the CAD model, which was modeled
using Solidworks, it consisted of a Main body for the PCB and LCD, an Appendix body for the
generator, which was broken down into the generator (stator) casing, the fan (rotor) casing and
the nozzle (mouth piece). Many concept CAD models were made testing shape, function, color
and layout; figure 10 shows the render of the selected concept model for further development
and testing.
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Figure 10: Peak Flow Meter Concept design
4.2. Peak Flow Meter Prototype01
The conceptualizations evolved into Prototype 01(P01), due to space restriction between
components and the size of the rotor and PCB. The P01 consist of a Main body structure, which
holds the LCD, PCB, Battery and the Stator and it’s a partial casing of the rotor, the Rotor lid to
encase the rotor and support the mouth piece, and the Mouth piece. During this stage, the P01
was 3D modeled, and a Reverse Engineering process was applied to the existing components
such as; generator, LCD, Electronic components, PCB, and battery. These were carefully
measured with a caliper, and 3D modeled in Solidworks one by one, resulting in different
assemblies which were used to check the space limitations, clearance, connectivity, final size,
mounting and housing of these components.
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Figure 11: Peak Flow Meter Prototype 01
4.3. Peak Flow Meter Prototype02
The aiming for this design was due to different factors, like; LCD power consumption, Generator
power, Battery recharge-ability, Size, USB port. This Prototype design can be broken down into
five components that are; the Main body, the Rotor Lid to hold the mouth piece, the Mouth piece,
the USB Cap, and the Battery Lid.
The main problem with these previous prototypes were the large volume, size and bulkiness ; the
weight and the generator efficiency and capacity, several studies were made to improve the flaws
on the previous concepts, one of these studies led to the idea of a new type of generator small
enough and powerful enough to provide with energy the entire circuit and achieve a functionality
above the performance of previous cases, another modification made took place in the overall
design of the PFM the purpose of this change was to make it lighter and smaller.
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Figure 12: Peak Flow Meter Prototype 02
4.4. Peak Flow Meter Prototype03 Design
The Peak Flow Meter was designed and drawn with Solid Works software. It’s shape follows the
main aspects of “Product Design”:
• Mechanics
• Ergonomics
• Aesthetics
But also taking into account the flaws and disadvantages of previous prototypes to conduct a
research based and directed to the objective of improve these characteristics, the main points
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aimed to develop in this prototype are size, volume, efficiency, generator power output, just to
name some of the desired advancements in this new design.
The idea of the new prototype began with a series of sketches and in analyzing these drawings
we concluded and arrived at a common decision for a main housing; the design of this casing
resembles a whistle, the reasons for this scheme is that a whistle is easy to hold, lightweight and
small giving us an ideal ergonomic factor.
The main components of this prototype can be divided in main lid, covering lid, rotor blades
or fan, generator, mouth piece.
In picture 13 the basic form and basic
components of the new prototype can be
appreciated, mouth piece would be placed
in the air inlet on the downward part of the
sketch and the air outlets allow an
uninterrupted flow of fluid, the main idea
of this design went evolving when more
information became available, for example
one of the principal changes was the
generator since the generator in this first
design was going to be the same generator
as the previous prototype.
The use of this generator would mean a much larger peak flow meter and the ergonomic factor
would have been lost; being this last one really big it would have to have been attached on the
outside of the peak flow meter making it bulkier and adding more volume to the first design, this
generator would have been placed on the main lid (white) of the peak flow meter.
Figure 13: Peak Flow Meter Prototype 03
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The flowing picture shows different views of the first sketch of the P03 (prototype 03) in this
picture we can appreciate the mounting surface for the previous generator.
Figure 14: PFM Prototype 03 views
Figure 14 shows the different views of the first design for the peak flow meter prototype 3, the
design has changed completely from its predecessor but the P03 follows the same principle as
P01 and P02 concerning operation, with a few minor differences in layout and results. This
particular shape provides a more ergonomic design, approaching even more to the “hand held
device” statement we aim for.
On the back view the mounting platform for the previous generator can be observed, although is
a powerful source of energy for the recharging of batteries and the power supply to the circuit its
main disadvantage is its size so a further modification to this design took place.
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4.4.1. Peak Flow Meter Prototype 03 Version 2
In this version some huge changes were made, this includes the removal of the outside generator
and the removal of the mounting surface for the generator imbedded on the main lid; following a
new covering lid design (green lid in figure 13) to which some palettes are attached, these
attachments serve as supports for the coil that is going to be winded on the inside of the covering
lid, the magnets are going to be mounted inside as well more precisely on the rotor blades.
The following picture illustrates in a clearer way the inside design of the rotors magnets and lids.
Figure 15: PFM Prototype 03 V2
1
2
3
4
2
5
6
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This is an exploded view, constructed in Solid Works, of the Prototype 03 version 2 to denote
and point at the main components of this step on the design of the peak flow meter and the
fashion in which they are assembled; (1) it’s the main lid the main change in this part of the
prototype is the removal of the mounting surface used in past versions to secure the previous
generator in place, this lid also contains the air inlet and air outlets as well as the holder in which
the shaft is going to be mounted; (2) 3 mm bearing, these bearings are attached to the rotor blade
since the rotor blade is going to be the only moving part of this design; (3) rotor blades; (4)
magnet ring, the first idea for the magnet ring was to build it from twelve different magnets
alternating each one of them from N pole to S pole, in other words one north pole followed by
one south pole until the cylinder is completed; (5) palettes, the copper wire is going to be coiled
around these two sets of palettes, the purpose of the construction of two sets of palettes is two
embrace the magnets ring entirely one set of coils obtaining electromagnetic current from the
outer diameter of the ring and the second set working in conjunction with the inner diameter of
the ring; (6) and finally the covering lid.
4.4.2. Design of tester for the coil of the Peak Flow Meter
Prototype03
The power obtained from the generator was an important issue that needed to be improved. The
previous generator used in P01 was too small, and the power generated was not enough to
partially recharge the battery. And the generator of P02 was too big to be used in our design.
Having this new idea for an inside generator for the P03 a necessity to test this new configuration
arouse; since this type of coil wasn’t implemented in any of the previous prototypes our
information of it was not solid, this was just an idea it was not tested and knowing to work yet;
so we decided to move to the design table again to sketch and study the best way to produce a
test bench for this new set of coils in this configuration; we managed to come up with an
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unconventional design with minimum requirements, easy to operate, lightweight, small and
above all with a small amount of material and new parts used reducing its cost.
The tester is divided in three
main parts; (1) 3 mm bearing; (2)
coil and shaft support, this is
where the copper wire is going to
be coiled and this structure is
going to hold the bearings which
each one of them are going to
hold the shaft in place; and
finally (3) the magnet holder, this
magnet is going to be a
cylindrical magnet wrapped
around the center part of the
holder.
The wire is going to be coiled around the middle part of the tester; when the whole design is
assembled the two coil supports join together at the center and in this center is where the coil is
going to be placed.
Several tests were conducted to study the efficiency of the new generator, the main differences of
each test were the number of times the wire was coiled around the supports or the addition of a
steel clamp on the outside of the supporters to add more resistance to the magnets and generate
more electromagnetic current; the tests were conducted mainly with a configuration of 250
rounds and 400 rounds.
1
2
3
2
1
Figure 16: Tester exploded view
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4.4.3. Tests and Results
First test: Coil Diameter 0.12 mm; Rounds 250.
Peak Voltage: 0.35V
Frequency: 50Hz
Peak Amperage: 6.3mA
Second Test: Coil Diameter 0.12 mm; Rounds 250; addition of steel clamp.
Peak Voltage: 0.36V
Frequency: 58Hz
Peak Amperage: 6.5mA
Third Test: Coil Diameter 0.12 mm; Rounds 400.
Peak Voltage: 0.37V
Frequency: 58Hz
Peak Amperage: 4.63mA
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Fourth Test: Coil Diameter 0.12 mm; Rounds 400; use of steel clamp.
Peak Voltage: 0.41V
Frequency: 80Hz
Peak Amperage 4.85 mA
The voltage in all the tests resulted to be really low, the PFM needed at least 2 volts of energy to
run the circuit in the peak flow meter; the work was not over yet, further studies were conducted
and the information obtained lit up the research, the discovery made let us learn that the main
problem was in the distance from the coil to the magnet, this gap has to be as small as 0.1 mm
for this coil to work, at this distance this coil configuration can grant an energy output of 2 volts
at 200 rpm.
4.4.4. Peak Flow Meter Prototype 03 Version 3
A few more improvements were made to the P03 during the course of the development of the
design, these small modifications were made with the purpose of making easier the task of
closing and securing both lids together, and manage an easier cleaning or fixing of the devise;
the second change was the addition of more support for the center shaft; the multiple magnet idea
was discarded and instead a single magnet ring divided in four poles (two north and two south)
would be used; this led to a further modification of the palettes holding the coil reducing their
number from six to four.
The following picture denotes the final shape and configuration of the peak flow meter prototype
03; this model was also constructed in solid works and the covering lid is made translucent for
the better appreciation of the new palettes, magnet ring and overall internal configuration.
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Figure 17: Peak Flow Meter P03 V3
To better show the size of the PFM P03 V3 the following picture provides some dimensions in
an orderly fashion just to make the reader aware of the actual size of the prototype.
Figure 18: Peak Flow Meter P03 V3 Dimensions
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5. Future Enhancements
Future improvements need to be made to continue with the development of the Peak Flow Meter;
as previously mentioned before a designing of a new product requires a lot of attention and time
it is not a straight forward process, being an iterative set of steps new problems arise and with
these new problems new solutions are developed; the project will continue evolving as new
information becomes available; part of the future evolution process involves the implementation
of the new studied generator with a minimal distance between the coil and the magnet, the
addition of a more efficient rotor blades, and the inclusion of a solar panel to add in the
recharging of the system; these are merely a few ideas for upcoming prototypes.
6. Conclusions
The “Peak Flow Meter” has still a long road ahead of it, it is not a simple task but surely is a
highly rewarding one; from the beginnings of the conceptualization, to the first prototypes, to the
arrival at this final PFM a huge load of countless ideas have risen or fallen, some of these ideas
were taken into account and some of them discarded but the most important attribute of this
project is the dedication and care with which has been build, a merging of ideas results in better,
more reliable, and closer-to-the-objective products; a perceivable amount of improvement can be
seen from the first birth of the idea to the actualized P03.
I believe we accomplished and exceeded several of our objectives; reducing the size and volume,
thus making it more ergonomic and portable; managing a better understanding of the generator
and working our way to achieve the power needed; and overall obtaining a better product.
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7. References
[1] Kumar, Vinay; Abbas, Abul K; Fausto, Nelson; Aster, Jon (2010). Robbins and Cotran
Pathologic Basis of Disease (8th ed.). Saunders. p. 688. ISBN 978-1-4160-3121-5.
[2] Martinez FD (2007). "Genes, environments, development and asthma: a reappraisal". Eur
Respir J 29 (1): 179–84 http://erj.ersjournals.com/content/29/1/179.
[3] NHLBI Guideline 2007, p. 214.
[4] http://en.wikipedia.org/wiki/Peak_flow_meter#History
[5] en.wikipedia.org/wiki/Peak_flow_meter
[6] LUNGFUNKTION — Practice compendium for semester 6. Department of Medical Sciences,
Clinical Physiology, Academic Hospital, Uppsala, Sweden. Retrieved 2010.
[7] http://en.wikipedia.org/wiki/Restrictive_lung_disease
[8] http://www.efunda.com/processes/rapid_prototyping/intro.cfm
[9] http://en.wikipedia.org/wiki/Rapid_prototyping
[10] Narayan, K. Lalit (2008). Computer Aided Design and Manufacturing. New Delhi: Prentice
Hall of India. pp. 3.
[11] “Solid Works” http://en.wikipedia.org/wiki/SolidWorks
[12] “Solid Works Company History” http://www.solidworks.com/sw/656_ENU_HTML.htm
[13] “Solid Works company Information”
http://www.solidworks.com/sw/656_ENU_HTML.htm
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