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 ManifoldIntroduction: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 DeviceShort 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:

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 TeamIntroduction:

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 CoolingIntroduction 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 out-perform an actively cooled system, like a fan, without any power use. 

Mission StatementThe 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 closed-

circuit 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 TestingFlow 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.

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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.

Figure 2: Spray rack components (A)

water intake with adjusting valve, (B)

pressure gauge, (C) one of several spray

nozzles.

C

A

B

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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:

The spray rack has fixed frame dimensions

Materials used in the manufacturing of the spray rack are not ideal

Calibration of the apparatus is too difficult

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 ft2).

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 nozzles into

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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 human-

powered vehicle, consisting of a recumbent tricycle and detachable aerodynamic faring, capable of

winning the HPVC West and the attention of the local bicycling community.