Capstone Projects Order of Presentation 2010

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Capstone Projects Order of Presentation 2010
TRAM BRAKES
Project Background
The project sponsor, Zdenek Zumr, owns and operates a funicular tram at his residence. The driveway
at his residence rises at approximately a 30° slope, and is essentially useless for vehicular and pedestrian traffic
due to the steepness of the incline. The tram was installed with the intent of carrying both cargo and passengers
to and from the residence with less physical exertion than is required to navigate the thirty foot vertical rise
using the staircase. Since the tram operates on a single pull cable, an emergency braking system is required to
prevent the tram cart from descending down the track with loss of control in the event of a cable or winch
gearbox malfunction.
Purpose of the PDS Document
The Product Design Specifications (PDS) document sets the design constraints and performance criteria
that must be met by the design team when developing a product. This report will provide a project plan
including the dates of major milestones. The external and internal customers will be identified, and summaries
of customer interviews will be presented. The design criteria will be related to customer need, priority,
engineering metrics & targets, basis for target selection, and the verification method to be used to establish
whether the design criteria has been met. A House of Quality (HOQ) will also be included to associate
important customer requirements with measurable characteristics of the product.
Mission Statement
An emergency braking system for a funicular tram located at the project sponsors residence is to be
designed and prototyped. The braking system is to operate automatically in the event of a pull cable or winch
gearbox malfunction. The braking system should either stop the tram cart, or allow the cart to descend to the
bottom of the tramway at a controlled velocity of no more than 2 ft/sec. If the braking system is to stop the tram
cart, a provision for manual operation of the brake may be included to allow an occupant on the cart to descend
to the bottom of the tramway. The braking system must be reliable, mechanical (non-electrical), and operate
without the destruction of major braking system components. A prototype is to be installed and tested by early
June, 2010. Documentation of the mechanism, including Bill of Materials (BOM), operating and maintenance
instructions (O&M), and Assembly Drawings are to be delivered with the prototype. A final report and
presentation is to be given in early June 2010.
FSAE
Formula Society of Automotive Engineers
Intake Manifold
Introduction:
The Society of Automotive Engineers conducts an annual student design competition referred to
as Formula SAE (FSAE). Universities around the world compete as design teams in a
hypothetical corporation, for production of a marketable automotive race vehicle. To promote
creativity the design teams are limited to a restricted 610cc engine size.
The restriction occurs from a 20mm throttle restrictor on the air intake. According to FSAE
regulations all air to the cylinders is to pass through the restrictor with no throttling allowed
downstream. Complexities of the restricted flow and the overlap of valve timing produce
airflow problems. It is beneficial to design an intake manifold that best utilizes the available
airflow for increased performance.
Currently there are several issues with the intake system. These include lack of proper
analysis and documentation, increased weight from excess material, and improper fuel
injector selection.
Viking Motorsports has concerns about the design of the current intake, including fluid flow
and harmonics. Improper airflow can leave excess air in the plenum area, causing the
restrictor to suck less air. An intake manifold in proper resonance generates an air spring
effect to force more flow though the cylinders, resulting in a dramatic rise in the performance.
The 2008/2009 FSAE restrictor is constructed of an oversized throttle body, with a heavy billet
aluminum adaptor. The manifold is built of welded aluminum pieces, and is overbuilt for the
pressures seen by the manifold. With proper analysis wall thicknesses and material selection
can be appropriately generated.
Fuel injectors are another problem area. Viking Motorsports will be providing the intake team
with the injectors necessary. The intake team will then incorporate the injectors as part of
their design.
Explanation of what this document addresses:
The product design specifications document is to define what the intake teams objective
are and what the customer’s expectations entail. Current problems, design parameters, and
requirements are established with the design requests given and accord to importance.
Mission Statement:
The goal of the intake team is to experiment, design, optimize, and produce an intake
manifold for the Viking Motorsports FSAE team. A completed manifold must be done by
May15th in time to tune the car for national competition. Main constraints are adhering to the
size restrictions from the Viking Motorsports team, and the official rules of the FSAE
competition.
Ultra Slim Air-Moving Device
Short Introduction
The ever-present desire for small devices with greater computing power and battery life (i.e. CPU,
video cards, chip sets, memory, etc.) gives rise to the problematic issue of heat removal. In some cases
excessive heat generated by electrical components can limit the potential performance of a device or cause
outright failure. Fatigue due to thermally-induced stress cycles can also lead to shortened product life.
To address these problems it is desirable to provide a convective mode of heat transfer while
maintaining portability and the desired attributes of the portable electronic device, such as sufficient cooling
without sacrificing battery life, quiet operation and reliable function and size.
What document (PDS) addresses
This (PDS document) identifies:


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

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The problem to be addressed (providing a small air moving device with adequate air flow properties)
The project plan, which includes deadlines for prototyping and evaluation to ensure the design team
moves forward with development
Who the customers are and what their specific needs are
Customer feedback and input during the different stages of the design process
Criteria, customer need, priority, metrics, targets and test methods and verification
House of Quality, or the weighted assessment of different variables to be considered for meeting
customer requirements
Other critical issues pertaining to the development of the product
Mission Statement
The Intel capstone team will design and test a miniature air-moving device. The device will be designed
to output at least 0.075 actual cubic feet per minute (ACFM) of air flow with a maximum pressure of 0.045
inches of water gauge (IWG). The design will be constrained to be no larger than 3mm thick. The capstone
team will design, rapid prototype and test the air-moving device. Complete documentation of the project will
also be provided.
Green Roof Capstone Team
Introduction:
CH2M Hill Center, a 10 story commercial building located at 2020 SW 4th Ave in Portland Oregon, has
a traditional impermeable rock ballast roof system. The roof system is 25 years old and near the end of its
working life. The traditional roof facilitates storm water runoff; which contributes to building operations cost
and overflow of the Portland metro sewer/storm water infrastructure. The low reflectivity and high emissivity
of the rock ballast roof directly contributes to temperatures up to 40% greater than ambient air on the roof.
Elevated temperatures and direct solar radiation combine to degrade roof performance, resulting in higher O &
M costs. Green/Eco roofs are roof systems founded on a reinforced roof structure with the addition of a
waterproof membrane, additional insulation, a drainage layer, a root barrier, soil and plants. The teams’ goal is
to design a green roof system and instrumentation module that will quantify the impact of design optimizations.
Data collected will assist in making roof replacement recommendations to CH2M Hill management and provide
input for CH2M Hill to produce a CFD model of the proposed replacement green roof.
Purpose of this Document:
The report is a reference for the design and performance criteria set forth by the customers. The PDS
defines stakeholders, outlines a design project plan and the design teams intention. Design requirements,
engineering metrics, targets and evaluation methods are identified and prioritized.
Mission:
The Green Roof Test Module team will design and construct a scale green roof and green roof
instrumentation system structurally, thermally and hydro-logically tailored for CH2M Hill Center’s 5th floor
terrace. The design will require a green roof test module that is easily moved (portable) and meets terrace
structural load limit and municipal code. The design will be documented by a report that contains details of:
targets, analysis methods, material selection, instrument selection, as well as drawings and economic analysis of
the proposed replacement roof.
Netbook Passive Cooling
Introduction
As electronic devices began to shrink in size and come in contact with users more, the need for cooling, for the
comfort of the user and the safe operation of the device, became a critical issue. This issue is most apparent in
personal computing where these devices have become smaller, faster and more integrated into people's lives.
In the early days of computing there was thought to be a "thermal barrier" limiting how fast a processor could
be run. However, as processor density and complexity have increased, so have the cooling techniques used to
remove heat from critical hot spots such as processors. Globally, a considerable amount of power is used in the
thermal management of personal computers. This is due to the fact that most of the cooling solutions currently
employed are powered, or active, such as the now standard fan.
The fan is not a wholly inefficient design due to its integration with non-powered, or passive, technologies like
heat sinks, spreaders and pipes. However, the ideal solution would disperse the excess heat without the aid of a
powered component. The benefits of a system like this are obvious for most devices, but more so for portable
devices whose battery power is limited. Thermal management of portable computers continues to be a great
challenge.
Active cooling solutions, such as fans, have several disadvantages that are undesirable for the producers and
users of these devices. Active cooling solutions add complexity, are often noisy, and reduce battery life. A
passive system would strive to eliminate noise, reduce power consumption, and extend battery life, while still
providing the cooling the device needs. In order for our team to accomplish this we will need to match or outperform an actively cooled system, like a fan, without any power use.
Mission Statement
The capstone team will design, fabricate, and deploy a passive cooling solution to replace the actively cooled
system of a MSI Wind netbook computer. The passive solution will provide the same cooling capability as the
current active solution with its performance measured by both component and skin temperatures.
Optical Mounting System for Laboratory Research
Introduction:
In the publication Optics, by Isaac Newton, it is explained that the index of refraction of fluid media is in part a
function of the density of the fluid. Robert Hooke developed schlieren photography in the mid 17 th century as one of the
first forms of flow visualization in transparent media [Appendix A, Figure 3].
Through experimentation, Hooke
successfully developed the first means of separating light distorted by density gradients in a fluid. This development lead
to the visualization of transparent media was integrated into the scientific community as both a fascination and as
laboratory discipline
In successive incarnations over the last three centuries, schlieren imaging has undergone extensive improvement
and modification. One of the most functional applications of schlieren imaging is with wind tunnels. Schlieren imaging
makes otherwise transparent fluid phenomena visible in real time and has become an indispensable tool in making both
qualitative and quantitative measurements.
In supersonic and hypersonic wind tunnels, schlieren photography is
frequently used to visualize shock cones and sound barrier phenomena as they vary with fluid velocity [Settles, 2001]. In
subsonic wind tunnels, such as the one currently being constructed for Portland State University (PSU), this technique is
used to visualize boundary layers, turbulence, recirculation zones, and other fluid phenomena.
Although a versatile research and laboratory tool, there are aspects of schlieren imaging that limit its use. One
such drawback of this technique is that it requires many optical components to be carefully aligned in order to properly
focus the area of interest. Component arrangements vary; the type to be used at PSU is known as a single-mirror off-axis
schlieren system. Figure 1 shows this system arrangement which contains: a parabolic or spherical mirror of medium of
large focal length (at least 1 m), a filter in the form of a slit or diffraction grating, a knife edge for further filtering, a
camera, and optionally, two double convex collimating condenser lenses. All of these components need to be carefully
arranged in order for the schlieren system to produce meaningful data.
Figure 1: Schlieren imaging optical components configured as a modified single-mirror
off-axis system.
Mission Statement:
The mission of this project is to design an optical mounting system to enable imaging within the test chamber of a
wind tunnel. This system will allow all necessary optical components to be moved in concert to increase the imaging
capabilities of the laboratory and reduce time required to setup and execute experiments.
Project Summary:
A major drawback of schlieren imaging is that many components need to be focused and aligned in order for the
system to function. In the case of a wind tunnel, this means that only one area of interest can be imaged at any given time.
In order to focus on any other part of the tunnel, the components must be dismantled and reassembled elsewhere.
Portland State University’s Department of Mechanical Engineering is currently awaiting installation of a closedcircuit sub-sonic wind tunnel [Appendix A, Figures 4 & 5]. The primary function of this wind tunnel is to assist
department faculty in fluid research. Current research plans involve the use of strategic imaging to quantify fluid
phenomena indistinguishable with the human eye. Imaging techniques utilized include Schlieren photography and
tomographic PIV. Both techniques require optical components precisely positioned around the wind tunnel to properly
image the area of interest.
The goal of this project is to design, develop, and prototype a mounting system able to image any portion of the
wind tunnel without the need to disassemble, relocate, and reconfigure the apparatus. This mounting system will hold all
necessary components in focus and allow them to be moved in concert. The mounting will enable visualization of fluid
phenomena throughout the wind tunnel.
Fish Neuron Testing
Flow Tank
Synopsis
Fish respond to small variations in water flow by means of tiny sensors along the fish’s body. It is
theorized that these sensors detect pressure changes and send a signal to the brain that is interpreted by the fish
as a change in water velocity. This information is used by fish to detect predator strikes, prey movements and
to adjust position to minimize energy expenditure in a flow stream. The goal of this project is to design a flow
tank that will allow biologists to observe and study the interaction between fish brain neuron responses and bulk
water flow rate and flow angle. This project will require the design of a tank that will allow for laminar flow,
adjustable flow rates from stagnant flow to a flow of 100 cm/s that lasts for at least 1 minute, and the ability to
change the tank orientation +/- 15°.
Mission Statement
The project is to design a flow tank used by PSU biologists to test fish neuron responses from the lateral
line sensory organs. It is predicted that specific neurons fire in response to the angle and velocity (speed) of
water flow, but this has not been shown. The tank will have the capabilities of a variable water flow speed and
variable flow angle. The ideal flow tank design will allow constant laminar flow, adjustable flow rate and angle,
vibration minimization, portability, and static control over fish so that sensory organs remain under water
without full submersion. Completion of the project will be in June of 2010.
Customer Base
This project is specifically meant to meet the needs of the Portland State University (PSU) Fish Biology
research team headed by Dr. Randy Zelick. This topic is of great interest to fresh water and marine biologists
interested in fish population management. As an example, mitigation of the hydrodynamic consequences of
dam turbine flows on fish behavior requires the understanding of how fish process water flow parameters. It is
also of potential interest to engineers interested in flow sensor technology, and the development of undersea
vehicles.
Completion Date
The completion of this project is scheduled for June, 2010. The results of this project will be presented
at the final PSU Senior Capstone project presentation in May, 2010. A report will also be completed and
submitted to the team’s Capstone advisor.
Automated Fluid Perfusion System for a Tissue
Synthesis Bioreactor
Introduction
Millions of people suffer some type of tissue loss, damage, or bone defect every year. Medical treatments for such
conditions include autografts (a tissue graft obtained from one part of the patient’s body for use on another part),
allografts (a tissue graft from a donor genetically unrelated to the recipient), and metallic implants. These methods
suffer from limited availability, reliance on a limited number of volunteer donors, and there are issues of potential
immune system reaction from allografts and metallic implants resulting in rejection of the graft. For that reason,
many patients are still suffering from tissue loss or bone defects.
However, the science of tissue engineering provides medical solutions to these problems by the development of
substitutes that restore and maintain tissue functions. An in vitro tissue-engineered bone for subsequent implantation
in vivo is being developed as one of these solutions. In particular, an in vitro engineered cartilage replacement is
being pursued as a way to repair injuries and damage to cartilage, especially in joints.
Bioreactor devices are designed specifically to support such tissue engineering applications. A typical Bioreactor
system will hold test samples consisting of synthetic scaffolds seeded with cells which form the base of the final
engineered-tissue. These scaffolds are then supplied with a nutritive fluid or gel consisting of cells, biomaterials, and
growth stimulants. Tissue growth is then encouraged by stimulating the cells. This can be done via several methods,
including fluid proliferation through the scaffolds, and mechanical loading stimulation. The full device is placed in
an incubator that maintains the temperature, gas percentages, and humidity at certain levels to simulate the
environment inside of the human body.
The nutritive fluid in the bioreactor system needs to be replaced periodically in order to supply the cells with fresh
nutrients, to remove waste products, and to allow effective scaffold proliferation. However, the current bioreactor
system in development by the Portland State University (PSU) bioengineering department research team does not
have a perfusion system and the fluid replacement is done manually. The manual process involves opening the
incubator and changing the fluid by hand. This disrupts the equilibrium within the incubator, which slows down
tissue growth. Therefore, the capstone team was asked to design and fabricate a fluid perfusion system to be installed
to the current bio reactor system to allow automated nutritive fluid replacement.
Purpose of This Document
This document contains the design criteria presented by the various customer groups, the targets that should be
attained for each, the engineering requirements for each design element, and the customer’s priority of each
presented metric. In this regard the PDS is the benchmark against which the success of the final design will be
evaluated.
Mission Statement
The Bioreactor Capstone team will design, prototype and install a device that will transport a nutrient gel into small
square test cells. The device will fit inside an incubator with bioreactor and not interfere with the other testing
devices that monitor the cells. In addition the system will be automatic, pressure resistant, and easy to install. The
project will be documented extensively with reports, visual aids, and presentations. A working prototype is to be
installed by the end of June.
WATER Penetration
Test Apparatus
INTRODUCTION TO THE PRODUCT
Morrison Hershfield acts as a third party, testing the resistance of installed windows, skylights,
and doors to water penetration. The apparatus used during these tests is known as a spray
rack. The current design used by Morrison Hershfield is shown in figure 1. A spray rack must be
connected with a hose to a water source, such as a standard garden hose tap, as outlined in the
ASTM E 1105-00 Standard. The hose outlet is connected to an adjusting valve, shown in figure 2
part A, which constrains the fluid flow entering the test apparatus. A pressure gauge is installed
on the frame of the apparatus to measure the fluid pressure within the device (figure 2
component B). Water passes through the pipes of the testing apparatus at a pre-determined
water pressure, and exits through a series of uniformly spaced nozzles onto a test specimen.
The nozzles can be identified in figure 2 as part C.
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Figure 1: The water penetration testing
apparatus (spray rack) currently used by
Morrison Hershfield.
C
B
A
Figure 2: Spray rack components (A)
water intake with adjusting valve, (B)
pressure gauge, (C) one of several spray
nozzles.
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There are a number of critical flaws with the testing apparatus used currently by Morrison
Hershfield during water penetration tests that may affect performance and ease of use. These
design flaws pertain to the following issues:
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The spray rack has fixed frame dimensions
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Materials used in the manufacturing of the spray rack are not ideal
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Calibration of the apparatus is too difficult
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Flow rates from separate nozzles can be considered inconsistent or unreliable
Fixed Frame Design
The rigid frame of the current spray rack makes for awkward transportation and requires the
use of a second spray rack to conduct large scale application tests (specimens larger than 32 ft 2).
Set up of the passive device takes a minimum of two people due to its inept construction. The
team will design a modular rack that can effectively spray specimens ranging from 2 x 2 ft up to
10 x 10 ft. A variable frame design will improve portability, enhance usability, and broaden the
range of testable specimens.
Test Apparatus Materials
Copper tubing was chosen to construct the frame of the existing test apparatus. Water
penetration tests are often conducted on construction sites in which heavy machinery, and
impact hazards commonly exist. Figure 1 shows blue duct tape wrapped around part of the
frame. The tape was put in place to cover a hole obtained on a job site. To achieve a stronger,
more reliable frame, the team will evaluate different materials to construct a more robust
device.
Calibration Difficulties
Every six months the spray rack must be calibrated to meet the required target wetting rate of 5
gal/ft2 hr, and to validate a uniform spray distribution. This is done by conducting a typical
water penetration test into a catch box. Figure 2 shows the catch box that Morrison Hershfield
uses to calibrate their spray rack. The catch box gathers the impinging flow from the spray
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nozzles into measuring devices that allow the user to calculate the flow exiting the rack. If the
calculated rate of flow meets the requirements of 4-10 gal/hr for each quarter of the catch box,
the respective water pressure is recorded and the rack is considered to be calibrated.
Figure 3: Catch box used in the calibration of
Morrison Hershfield’s spray rack.
Difficulty calibrating the test apparatus has become an issue, due to the lack of connectivity
from the rack to the catch box. The absence of any type of mounting system results with the
user holding the catch box on top of a random object in front of the spray rack. In addition,
there are also inaccuracies in the water volume gathered during the calibration due to leaks in
the pipes (shown in figure 3). To increase the efficiency and accuracy during calibration, a new
catch box will be fabricated to easily connect with the spray rack via hoisting points or clips to
ensure proper gathering of all sprayed water.
Inconsistent or Unreliable Flow Rates
Upon visual inspection, there is notable differences in water pressure when comparing nozzles at
different locations on the spray rack. The nozzles located near the top of the rack have notably
less pressure than those near the bottom. In order to obtain accurate, compliant spray coverage
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of each specimen, the team must engineer consistent pipe pressures at each nozzle throughout the
rack.
STATEMENT OF PURPOSE
This document outlines the requirements, goals, and plans of our design team for an explicitly
constrained project. The project’s constraints are defined by the ASTM E 1105-00 Standard, as
well as the engineers and end users at Morrison Hershfield. Priorities for various aspects, such
as operational performance, reliability, ease of use, and a project timeline are presented.
MISSION STATEMENT
The Water Penetration Test Apparatus team will design a spray
rack system to exceed the performance and usability of Morrison
Hershfield’s current testing device. In addition, the rack will be
designed to meet all of the calibration testing standards outlined
in the ASTM E 1105-00 document by manufacturing a new, easy
to use, catch box.
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2010 HUMAN POWERED VEHICLE
Introduction
As the price of oil and the release of harmful pollutants into the environment exponentially
increases, new forms of efficient transportation must be explored. For this reason the American
Society of Mechanical Engineers (ASME) developed Human Powered Vehicle Competition (HPVC) for
senior level mechanical engineering students in 1983. Revealing to the general public the practicality
and efficiency of human powered vehicles is one goal of the competition. Another, combine the many
sub-disciplines of mechanical engineering (gear design, material science, fluid dynamics, biomechanics,
and linkage design) into one comprehensive design project. The 2010 PSU HPV team will be judged
against teams from all over the world at the 2010 Human Powered Vehicle West Coast Competition
(HPVC West) in Northridge, CA.
The HPVC organizers have developed stringent rules for race vehicles to encourage efficiency,
rider protection, and innovation. This is done through four separate events: a 600-800m drag race, a
2.5 hour grand prix style endurance race, a 2km closed loop utility race, and a report, detailing the
vehicle’s design, safety, and formal presentation. HPV’s will overcome the limitations of traditional
bicycles by utilizing an aerodynamic fairing, a low center of gravity to increase stability, and an
ergonomic seat that is comfortable over long durations. One motivation for this project is to introduce
the general population to innovations in human powered transportation, the team will also present
and/or compete with the vehicle at community events and cycling races in Portland, OR and the
surrounding communities.
It is the 2010 PSU HPV team mission to design a competitive, innovative, and intuitive humanpowered vehicle, consisting of a recumbent tricycle and detachable aerodynamic faring, capable of
winning the HPVC West and the attention of the local bicycling community.
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