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American Society of Mechanical Engineers
Human Powered Vehicle Team
ME 493 Final Report - Year 2008
6/4/2008
Design Team:
Ben Bolen
Erik Chamberlain
Kenneth Lou
Levi Patton
Bryan Voytilla
Academic Advisor:
Derek Tretheway
Industry Advisor:
Faryar Etesami
Sponsor:
American Society of Mechanical Engineers
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Executive Summary
The Portland State Human Power Vehicle design team designed and constructed a fully faired
aluminum bicycle for use by the Portland State Human Powered Vehicle Race Team in the
ASME Western Regional HPV Challenge named Vike Bike. Vike Bike is a recumbent, rear wheel
drive bicycle covered by a full fairing.
Frame geometry was established based on previous years HPV design team research into
optimal power angles for the human body while riding a bicycle. The configuration is a rear
wheel drive, recumbent bicycle with front wheel steering, a fixed seat, and an adjustable boom.
Power is delivered to the rear wheel via a custom made chain ring attached to the adjustable
boom; the chain is routed underneath the frame by way of three idler gears. An integrated roll
bar and a five point seat belt provide safety protection for the rider. 6061-T6 aluminum of
varying size and wall thickness was used to construct the frame.
The fairing was designed using Nation Advisory Committee for Aeronautics shapes optimized
for pressure recovery. The fairing was constructed with three layers of S2 fiberglass and either
a Baltek Mat or balsa wood core.
Materials testing and computer analysis were performed on the frame and fairing to optimize
their design for criteria such as weight or strength. Explanations of these analyses are included.
The Portland State HPV race team continued its tradition by finishing third overall in the
Western Region HPV Challenge for the third year in a row. The race served as a testing ground
for vehicle design and survivability; lessons were learned in systems performance as well as the
overall quality of design which can be implemented by future Portland State HPV design teams.
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Table of Contents
Executive Summary .......................................................................................................................... i
Introduction and Background information ..................................................................................... 2
Mission Statement .......................................................................................................................... 2
Main design requirements .............................................................................................................. 2
Top Level Design alternatives ......................................................................................................... 3
Design Concepts .......................................................................................................................... 3
Frame........................................................................................................................................... 4
Fairing .......................................................................................................................................... 4
Mechanical Systems .................................................................................................................... 5
Final Design and Evaluations .......................................................................................................... 6
Frame........................................................................................................................................... 6
Fairing .......................................................................................................................................... 9
Mechanical Systems .................................................................................................................. 13
Future Design Considerations ....................................................................................................... 15
Frame......................................................................................................................................... 15
Fairing ........................................................................................................................................ 15
Mechanical Systems .................................................................................................................. 16
Conclusion ..................................................................................................................................... 18
Appendix A: Safety ........................................................................................................................ 19
Appendix B: Maintenance ............................................................................................................. 20
Appendix C: Initial Design Concepts ............................................................................................. 21
Appendix D: Product Design Specification.................................................................................... 26
Appendix E: Frame Analysis .......................................................................................................... 30
Appendix F: Biomechanical Testing .............................................................................................. 46
Appendix G: Braking Analysis ........................................................................................................ 48
Appendix H: Top Speed Analysis ................................................................................................... 49
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Appendix I: Turning Analysis ......................................................................................................... 53
Appendix J: Strain Gauge Testing.................................................................................................. 57
Appendix K: Fairing Aerodynamic Analysis ................................................................................... 60
Appendix L: Fairing Material Analysis ........................................................................................... 64
Appendix R: Vehicle Stability ........................................................................................................ 67
Appendix M: Frame Design Drawing ............................................................................................ 69
Appendix N: Fairing Design Drawings ........................................................................................... 81
Appendix O: Vike Bike Dimensions ............................................................................................... 85
Appendix P: Glossary of Human Powered Vehicle Terminology .................................................. 86
Appendix Q: Bill of Materials ........................................................................................................ 87
References .................................................................................................................................... 93
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Introduction and Background information
Because of increasing energy prices and growing concern over vehicle pollution the American
Society of Mechanical Engineers (ASME) created the Human Powered Vehicle (HPV) Challenge
to encourage development in human powered technology. The goal of the HPV Challenge is
that someday a HPV will be designed that is practical enough for everyday uses such as going to
the store or commuting to work.
The ASME HPV Challenge is a competition in which engineering students from around the
country design, construct, and race an HPV. An HPV can take many forms and varying rider
positions, such as upright, recumbent, or prone and can have any number of wheels. The
competition consists of three separate events: a 100m sprint race, a 65km grand prix style
endurance race, and a judging process for the vehicle’s design, safety, and formal presentation.
For the third consecutive year the Portland State University (PSU) chapter of ASME competed in
the HPV Challenge. Having placed third the two previous years the team sought to improve
upon those finishes and win the overall competition. A design team of five mechanical
engineering seniors was formed to design and construct an HPV for use in this competition.
Mission Statement
The goal of this project was to develop an innovative, light-weight, and aerodynamic HPV for
the Portland State HPV Race Team to win the overall ASME Western Region HPV Competition
on April 18th, 2008, and to complete it within time and budgetary constraints.
Main design requirements
During the initial portion of the design phase external and internal searches were conducted
into HPV design. The goals given in Table 1 were the preliminary design goals for the project.
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Metrics were developed to quantify the targets. The outcome of the goal is given in the right
hand column of the table.
Table 1: Initial design goals
Evaluation of Design Goals
Metric Target Produced Target Met?
Top Speed >45 mph 39 mph No
Stopping Distance Less than or equal to 20ft from 15 mph 10 ft Yes
Frame Factor of Safety > 1.5 Competition research Yes
Fairing Strength Greater than or equal to 2007 PSU HPV fairing Competition research No
Crash Recovery Time < 15 seconds 11 seconds Yes
Turning Radius < 25 ft Competition research Yes
High Speed Stability Does not wobble uncontrollably above 20 Mph
Does not wobble uncontrollably above 20 Mph Yes
Stright line aerodynamic efficiency Cd less than or equal to 0.14 0.04 Yes
Partical fairing removal for rider entry and exit <60 seconds 20 seconds Yes
Durration of HPV life in service Greater than April 2008 Still functioning after April 2008 Yes
Visual Appeal 30 Points 7 points No
Use of industry standard bike tools 100% 100% Yes
Total vehicle weight less than 50-lb Total weight 45-lb Yes
Rider Visibility Horizontal > 150 degrees Vertical > 60 degrees
Horizontal > 150 degrees Vertical > 60 degrees Yes
Fairing Strength Modulus of elasticity >= Vike Trike II < Vike Trike II No
Rider Comfort Low fatigue on rider Low fatigue on rider Yes
Rider Exchange time < 60 seconds 30 seconds Yes
Overall HPVC Finish First Place Third No
Under Budget $11,004.75 $12,725.41 No
Top Level Design alternatives
Design Concepts
During the design process initial conceptual sketches were made of potential HPV
configurations. These design ideas consisted of various vehicle, drive train, and fairing
configurations as well as different rider positions. These initial design concepts can be seen in
Appendix C.
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Frame
A top-level conceptual design required a decision on whether the vehicle would be configured
as a bicycle or a tricycle. The performance requirements of top speed, stability, weight
reduction, crash recovery, and straight-line aerodynamic efficiency are affected by the design
decision. Differences in amounts and types of materials used can affect the cost requirement.
Bicycle and tricycle configurations were evaluated using pros and cons (see Table 2).
Table 2: List of pros and cons for bicycle and tricycle configurations. Bike Trike
Pros Cons Pros Cons
Less components means lower weight and cost
Low-speed instability Low-speed stability High-speed instability
Small frontal area Tolerancing (front and back wheel linearity)
Team has experience working on tricycle HPVs
Scrub of the wheels while turning
Low weight Rider change out requires pit crew assistance
Uncomplicated chain routing Steering design and use
Statistically proven to do well in a competition.
Crash recovery is complicated in a fully enclosed fairing
Rolling resistance is increased with third tire
Drive train has to be routed to avoid the front tire
Aerodynamic resistance is increased with hole in the fairing for the third wheel
The cons to the tricycle configuration are inherent to the tricycle design. Cons to a bicycle
configuration can be overcome with engineering. The pro tricycle experience can also be used
to help the team with building a bike. The small frontal area and low weight of a bicycle would
be difficult (or impossible) to transfer to a tricycle setup. Therefore, the decision was made to
go with the bicycle configuration.
Fairing
Several concepts were developed during initial design for the fairing, a partial frontal fairing and
a full fairing. In general, the configuration of a fairing is determined by the end use of the
vehicle. If the vehicle is intended to be used at high speeds then a full fairing is beneficial
because of the reduced drag forces, however if the vehicle spends the majority of its time at
low speeds a partial fairing is preferred due to its low weight. Previous years experience
identified high speed efficiency as critical in both the sprint and endurance competitions.
Taking these and other attributes into consideration, a table that addresses the pros and cons
of each configuration was created.
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Table 3: A comparison of three possible fairing configurations Symmetrical Full Fairing Non-Symmetrical Full Fairing Partial Fairing
Pros Cons Pros Cons Pros Cons
Moderate manufacturing cost
High weight when compared to the partial fairing
Best reduction of drag force
High manufacturing cost
No manufacturing cost
Low reduction of drag force
Moderate manufacturing time
Poor crash recovery High manufacturing time
No manufacturing time
High materials cost High materials cost Low materials cost
Reduction in drag force is nearly as good as the non-symmetrical fairing
Good visibility must be designed
High weight when compared to the partial fairing
Low weight
Ventilation must be designed
Poor crash recovery Best crash recovery
Good visibility must be designed
Good rider visibility is inherent
Ventilation must be designed
Good rider ventilation is inherent
Though the partial fairing has the most pros, they do not compensate for its deficiency in drag
force reduction. The non-symmetrical fairing potentially has the highest reduction in drag force
but the time and cost associated with such a design is prohibitive for the 2008 PSU HPV team.
Given these constraints the symmetrical full fairing is the chosen design.
The symmetrical design reduces manufacturing time and cost by requiring fewer positive and
negative molds to be produced. Only a single negative mold is needed to produce both the top
and bottom half of the fairing since the intended shapes are identical. Keeping this
manufacturing process in mind, the shape of the fairing can be designed conforming to the set
of design requirements outlined in Table 1:
Reduced drag force when compared to previous PSU fairings
Complete coverage of the bike frame and rider (full fairing)
Accommodations for rider ergonomics
Mechanical Systems
The configuration of mechanical systems on the HPV was sought to optimize ease of installation
as well as overall performance and durability. Three mechanical sub systems on the HPV that
were examined for alternative designs are brakes, drive train, and steering.
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Several types of Front Wheel Drive (FWD) drive trains where examined, including: a swinging
boom, a u-joint, and a twisting chain. Each type of FWD uses a crank and gear set on the front
of the vehicle and a cassette on the front wheel of the vehicle. A swinging boom uses a boom
that is fixed to the fork of the vehicle, so that the boom turns when the front wheel turns. For a
u-joint drivetrain, power is transmitted from a boom (which is fixed to the frame) to the front
wheel. The twisting chain setup uses a fixed boom with a turning wheel, where the chain derails
slightly when the vehicle is turning. Table 4 is a list of pros and cons between choosing either a
FWD or RWD system.
Table 4: Drive Train Configuration Pros and Cons FWD RWD
Pros Cons Pros Cons
Small chain line, high
efficiency
Limited wheel size and
gearing constraints
Ability to use large wheel while
keeping center of gravity low
Long chain line, low efficiency
Easy chain routing Chain twisting will cause pre-
mature ware of chain.
Conventional configurations
and proper use of parts
Complicated chain routing to
rear wheel
Complicated configuration
provides expensive parts
Use of commercially available
parts
Final Design and Evaluations
Frame
The Vike Bike frame design is based off of the similar 3D space frame that was used for the Vike
Trike II with a few exceptions. The Vike Bike used the same body configuration angel (BCA) as
the Vike Trike II to achieve maximum possible rider force output while maintaining low rider
fatigue. The experiment performed by Reiser, of Colorado State University (2001), indicates
that a BCA between 130° and 140° is most efficient (see Figure 1).
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Figure 1: Rider position study for maximum recumbent power input (Reiser, 2001)
Additional literature review (Landwer and Too 2003; Too 1990; Too 1991; Too 1994; Too 1995)
was used to set rider configuration angles and frame sizes. The geometry for the 2008 Vike Bike
was modified slightly during the analysis to simplify manufacturing, provide stress relief, and
add stiffness. Figure 2 shows the current Vike Bike riding configuration.
Figure 2: Vike Bike frame configuration geometry
The existing design of the Vike Trike II was proved to be effective and efficient. This provided
the PSU HPV design team with a conceptual model to base the design of the Vike Bike from.
The greatest change in design of the frame was to configure the Vike Trike II (Figure 3) into the
configuration of a recumbent Bike while maintaining low rider position of 11.0” and long wheel
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base for recumbent bicycles of 54.95” for stability. Using the adjustable boom rather than an
adjustable seat proved to be the most efficient way to accommodate the difference in rider
height for the 2008 Vike Bike race team.
Figure 3: 2007 PSU Vike Trike II frame, Isometric view
The Vike Bike is manufactured of aluminum 6061-T6, providing the strength and light weight
desired by the PSU HPV Vike Bike design team. Figure 4 presents the 2008 PSU Vike Bike.
Similar to the Vike Trike II the Vike Bike’s roll bar is welded directly to the main tube to provide
stiffness. The frame height of the Vike Bike was raised to 8 ½ ” from the Vike Trike II’s 5 1/32”,
this was needed to fit a smaller 451 recumbent bicycle wheel and still maintain a short overall
rider height of 11” (see Figure 3). A glossary of Vike Bike components can be found in Appendix
A.
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Figure 4: 2008 PSU Vike Bike frame, Isometric view
Fairing
Using experience gained from previous years of HPV competition, a full fairing was chosen for
both the sprint and endurance events. Though previous years have used a partial fairing for the
endurance event, it was evident that a fully faired vehicle could increase overall velocity and
provide better protection to the rider during a crash. With the symmetrical full fairing design
chosen, the planar shape of the fairing was the next design consideration. The 2007 HPV team
used a planar shape provided by the National Advisory Committee for Aeronautics (NACA). The
shape was chosen for its pressure recovery attributes as well as incorporating the geometry of
the Vike Trike I and II. Selection of the planar geometry for the 2008 Vike Bike was done by
using a 6-series NACA shape that would contribute to a reduced drag force while closely fitting
the shape of the 2008 Vike Bike. A comparison between the 2007 and 2008 planar shapes is
presented in Table 5.
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Table 5: A comparison of the Planar shapes for the 2006 and 2008 HPV fairings PSU 2007 Planar Shape PSU 2008 Planar Shape
Pros Cons Pros Cons
Good pressure recovery Frontal area is larger than
necessary for the 2008 bike
Better pressure recovery due
to increased laminar flow
Space for pedals and feet will
be reduced.
Plenty of room for pedals and
feet
Smaller frontal area
One of the reasons for increased pressure recovery of the 2008 fairing is because its maximum
width occurs further from its leading edge. This is readily apparent when comparing Fig. 5 and
Fig. 6. Note that both fairings have a nose to tail length of 106”.
Figure 5: PSU 2007 Planar shape
Figure 6: PSU 2008 planar view
The leading 2 ft of the side view contour (see Figure 7) is determined by a NACA 4-series shape,
after that the geometry is governed by rider dimensions, the rollbar and toe box. The toe box
highlighted in pink in Figures 6 and 7 contribute to the fairings unique 3-dimentional shape.
The selected planar shape can only be used by keeping the faring walls nearly vertical from the
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nose to the beginning of the toe box. This results in the distinctive ridges that begin at the nose
of the fairing then blend into the rest of the body.
Figure 7: PSU 2008 side view
Rider visibility was designed concurrently with fairing shape since these features are
intertwined. Both window cutouts and a bubble canopy design were possible solutions for
rider visibility. Examples of these designs can be seen in Figure 8 and Table 5 lists pros and cons
of a bubble canopy versus window cutouts.
Figure 8: Bubble canopy (left), Window Cutouts (right)
Table 6: Pros and cons list of fairing shapes
Bubble Canopy Window Cutouts
Pros Cons Pros Cons
Full visibility with no
obstructions
Often times increases the
coefficient of drag
Reduced drag Visibility obstructions
Requires a single head
location for optimum visibility
Location of riders head inside
the fairing can be variable
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Tomai (1999, 195) discusses that the addition of a bubble canopy to a streamlined shape can
increase the coefficient of drag anywhere from 0.045 to 0.15. Beyond the aerodynamic
concerns, the bubble canopies advantage of an unrestricted view is overshadowed by the
necessity to engineer an adjustable seat to maintain a constant head location near the canopy.
Hence a fairing with window cutouts was chosen due to its streamlined shape and innate
accommodation of rider ergonomics. The window locations shown in Figure 8 (right) were
chosen to maximize rider visibility, fairing strength, and aesthetics this allows the rider to see
158o out of 180o which is an increase over previous PSU HPV fairings (see Figure 9).
Figure 9: Rider visibility provided by window cutouts
During the design of the fairing it was found that a completely symmetrical design was not
feasible due to bike and rider geometry. A simple solution was found that results in the nearly
symmetrical geometry, shown in Fig. 7, while still using a single mold system. The flat bottom of
the fairing is achieved through a simple and reversible modification of the mold. Figure 10
shows how this modification is done; inserting a “restrictor plate” changes the inner dimensions
of the mold.
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Figure 10: View of mold and plate
The plate is made of ¾” fiberboard that is painted and waxed so the surface matches that of the
mold. This simple modification requires little in manufacturing time and cost while retaining
the benefits of a single negative mold system.
A major deficiency of previous PSU HPV fairings has been the lack of a fairing latching system.
This year a system was designed to facilitate quick entrance and exit of the rider and keep the
fairing halves together in the event of a roll over. The Vike Bike latching system (see Figure 11)
consists of two wedges that, when mated at the fairing seam, restrict all horizontal movement.
Vertical movement is restricted by a Velcro strap. Eight of these latching points will be located
on the fairing. However, the four furthest mounts from the rider will not include Velcro.
Figure 11: Model of the fairing latching system
Mechanical Systems
Braking on the HPV is provided by a mechanical disk in the front and a cantilever pinch brake in
the rear. A mechanical disk brake was selected for the front wheel for its superior braking
Restrictor Plate
location →
Restrictor Plate
↓
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power and heat dissipation. A cantilever rear brake was required based on the use of a full
carbon wheel in the rear which necessitates a disk brake cannot be used.
External research was performed to determine the optimal body configuration angles (see
Appendix C). Rear wheel drive was selected because it provides increased turning ability and
high speed stability. Biomechanical testing was performed to find the power output available
from each rider (see Appendix F). A gear ratio analysis was performed with the biomechanical
data to find the required gear ratio to reach the target metric of 45mph (see Appendix F). The
final drive ratio required necessitated the manufacturing of 65 tooth and 75 tooth custom gears
because these sizes are not available commercially (Drawings available in Appendix M). The
donated gears were overbuilt, and holes were drilled into the gears to cut weight while keeping
manufacturing time down. FEA was used to optimize the amount of weight that could be drilled
out of the gears. A commercially available 10-speed Sram Force cassette and derailleur was
selected because of range of gears and light-weight (due to carbon fiber construction). A
thumb-shifter was mounted near the handlebars for ease of shifting. The final drive train
configuration consists of a custom made front sprocket on the front of the vehicle driving a
chain that is routed under the rider via three idlers to a ten speed cassette on the rear wheel.
The Vike Bike reached a top speed of 44mph under a high-cross wind situation. This value was
still close to the 45.28 mph top-speed calculated through the gearing analysis. The Sram Force
derailleur is a short-throw derailleur which performs well through a fixed range of gears and
chain length but was found to be very sensitive to changing boom length or crashes. After the
HPVC races, rider surveys were performed to compare the 65 and 75 tooth chain ring to the 53
tooth chain ring on the Vike Trike II. The 65 tooth chain ring was said to have provided a good
range of gear ratios in the endurance race and female sprint race, and the 75 tooth chain ring
supplied the highest PSU HPV speed in the mail sprint race.
The steering system for the HPV was designed based on the HPVC required 25 foot turning
radius as well as the goal of high speed stability. Two options for bicycle steering configurations
are front wheel or rear wheel steering. Front wheel steering was selected for its high speed
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stability and ease of use. A detailed analysis of the HPV steering system can be seen in
Appendix H.
Future Design Considerations
Frame
The Vike Bike was designed with a higher accuracy of forces exerted by the rider to the frame
compared to the Vike Trike II by using the biomechanical testing and incorporating the results
from the ASME roll-bar criteria. Previous years have also obtained dynamic rider data while
riding the bike is in a stationary trainer and collecting strain gauge data to apply to the frame
design for accurate modeling. David Van Dyke, the ASME Senior section Chair for the 2008-
2009 year, offered to donate a mobile dynamic strain gauge device that would allow the design
team to record dynamic road data for the future design of the vehicle. Acquiring these forces
will allow the future design teams to design and fabricate a lighter and stronger vehicle.
Other future design possibilities include a composite frame. Composite frames prove to be
stronger and lighter than a conventional metal vehicle frame. Extensive testing involving
materials selection is required for the development of a composite frame and is seen as a
drawback. Other testing drawbacks for using a composite frame include testing the adhesive
capabilities of bonding a composite to a metallic object.
Fairing
Although the balsa wood composite used for the 2008 Vike Bike fairing is stronger, lighter, and
more ductile than the 2007 Vike Trike II Baltek Mat composite, it was extremely difficult to
shape and form the balsa wood to the contours of the fairing mold. This resulted in voids and
gaps between the balsa wood sheets creating many weak points throughout the fairing
structure. Future designs should consider using materials that are easier to form into mold
contours.
In addition to material complications, the vacuum bagging layup process also resulted in weak
points throughout the fairing. Sufficient vacuum could not be produced due to leaks in the
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equipment and mold. As a result the material layers did not bond together leaving large voids in
the fairing. Future designs should consider using a vacuum bagging processes that can pull a
higher vacuum or leak proofing the mold and vacuum equipment.
Widow shaping and installation was a problem area for this year’s fairing. Acrylic was the
material used and is not optimal for this application. Another material should be sought for
future windows. Acrylic is a relatively brittle material that cannot withstand the impact of a
vehicle crash. During the competition weekend three windows were shattered and the sharp
edges could have done physical harm to the vehicle driver.
The acrylic windows are difficult to form without the aid of a dedicated thermoforming
machine. The windows must be cut and bent to shape in order to correctly fit the fairing and
blend neatly with the surface. The method used to shaped the windows for this year and
previous years has been to warm a single acrylic window with multiple heat guns then bend it
to shape. The heat guns do not uniformly heat the acrylic so localized warping occurs as the
windows are bent into place.
An alternative window would be to use thin sheets of lexan or mylar. These sheets a can easily
be cut to shape with scissors and then taped to the fairing. These windows are thin and will
most likely be destroyed in a crash. However, they are cheap (less than a dollar a window) and
are easily manufactured. Used as an expendable part, these would decrease manufacturing
time, cost and the end weight of the fairing.
Mechanical Systems
During the safety inspection, it was noted by the judges that the safety harness was not of
automotive quality because the use of plastic strap adjustments. In the future, the safety
harnesses should be made of high quality metal components and high strength straps.
The HPV crashed on the final lap of the endurance race, and an object was hit that forced
plastically deformed the 65 tooth chain ring. If a stress-strain curve is obtained for the type of
steel used in the chain ring, then FEA can be used to reverse engineer and find the amount of
force from a crash. This determined force can be useful when designing next year’s HPV. Using
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an intermittent shaft with a gear reduction can provide the same gear ratios as a 65 or 75 tooth
chain ring. This could eliminate the need for a larger gear, lighten up the main chain ring, and
allow the use of commercial available gears (where commercially available gears can be
replaced easier and faster than custom made gears).
Due to the problems encountered in using a 10-speed road bike derailleur and cassette, it is
recommended that a future design should incorporate a 7-speed mountain bike derailleur and
cassette. Seven speeds should be used because they can absorb more damage before it starts
to effect shifting, and it is expected that future HPVs will crash during testing and racing
situations. Mountain bike derailleurs have a larger throw than road bike derailleurs, which
could help alleviate shifting problems on the Vike Bike.
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Conclusion
This year marked another successful year for the Portland State HPV design team. The team
researched, designed, and constructed a novel HPV that was used by the Portland State HPV
race team to finish third place in the ASME Western Region Challenge. While not all design
goals were met, the majority of high priority goals were either met or nearly met. Innovations
were made in frame and faring design, as well as construction methods for the frame and
fairing.
Future design concepts were developed during the tenure of this project. A more effective
fairing attachment system would prove invaluable during the sprint and endurance
competitions. Also lessons have been learned with fairing construction as to core material
selection and vacuum bagging processes. Low speed stability also appeared as an issue during
the endurance race.
The design team recommends a fairing attachment system that uses magnets to retain the top
section of the fairing as well as only having as much of the top fairing removable as necessary
to maximize fairing stiffness. Large scale mock ups of fairing construction should be done
before fairing construction, which include curved surfaces to ensure that the core material and
manufacturing process are suitable for the fairing construction. Research should be done into
recumbent bicycle design in effort to find improvements on the bicycles design for low speed
stability.
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Appendix A: Safety
The following safety guidelines must be followed for safe operation of the HPV. Failure to
comply with guidelines may result in serious injury or death.
Always wear well fitting approved CPSC or Snell helmet while operating HPV.
Do not wear loose fitting garments while ridding the HPV, as well as making sure that
pant legs are tight ensuring they will not be pulled into the drive train.
Keep all body parts away from HPV drive train while in motion.
Do not touch the ground until the HPV has slowed to a stop.
Safety belt must be worn while the HPV is in operation.
Perform all regular maintenance on the HPV to ensure proper operation.
Do not ride the HPV at speeds above the rider’s ability.
Follow all traffic laws while operating the HPV on public roads.
Do not operate the HPV under the influence of alcohol, controlled substances, or
medication that way cause downiness.
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Appendix B: Maintenance
Regular maintenance of the HPV is required to keep the HPV in proper running condition. The
following is a schedule for preventative maintenance. In the event repairs are needed between
regular maintenance intervals they should be performed to keep the vehicle running safely.
Prior to every ride check
That the tires are properly inflated
The operation of brakes and brake cables
The tightness of the crank set After every ride check
Wheels for leaks or sharp debris picked up by tires during the ride
The trueness of wheels
Clean the bikes drive train and other mechanical parts if they have become dirty Every two weeks
Lubricate the chain Once a month
Clean the entire bike including the drive train.
Check the drive train for wear; looking for chain link tightness and repairing as necessary.
Lubricate all brake cables and derailers.
Check for looseness in the handlebar bolts, boom clamping mechanism, crank bolts, deraler bots, and the brake mounting bolts.
Replace tires as needed. Every Three months
Inspect the frame for cracking or signs of wear. Every six months
Inspect and adjust as needed headset, hubs, pedals, and bottom bracket bearings. Annually
Completely disassemble the bike replacing all bearings, breaks, and shift cables.
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Appendix C: Initial Design Concepts
In the initial design stage of the Vike Bike I each team member brainstormed for their ideal
HPV. Five concepts were developed varying from a two wheeled upright bicycle to a virtual
HPV.
Concept 1: Fully Faired Recumbent Bicycle
One integrated concept is to use a short wheelbase, recumbent, bike, with rear wheel drive, an
adjustable boom, a fixed seat, and a fully enclosed torpedo-shaped fairing with landing gear
that will be used in the endurance and sprint races (see Figure 1, below).
Figure C1: Sketch of Concept 1
Concept 2: Partial Front Fairing Upright Bicycle
This concept is based off of the common upright diamond framed bicycle sold in many bicycle
shops. Concept 2 uses front wheel steering and rear wheel drive, with the rider seated in the
upright position in an adjustable seat which compensates for different rider sizes (see Figure 2,
below). To satisfy the ASME competition rules the concept will utilize a partial fairing for both
endurances and sprint races.
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Figure C2: Sketch of Concept 2
Concept 3: Fully Faired Recumbent Tadpole Tricycle
Another concept would be a continuation of the Vike Trike II HPV with improved fairing design,
high speed stability, and drive train efficiency (see Figure 3, below). It should have three wheels
and be rear wheel drive. The seat should be fixed and the boom should be adjustable. The
focus will be on refining existing sub-systems rather than innovating new solutions.
Figure C3: Sketch of concept 3
Concept 4: Reverse Driving Fully Faired Tadpole Tricycle
The fourth concept integrates a fully-faired, recumbent, tadpole trike with RWD (see Figure C4
and Figure C5, below). Visibility is achieved via an integrated video system. The rider is
positioned with their head at the front of the vehicle to reduce chain routing and frontal area.
The riding position is not prone, merely backwards. Accommodation for different size riders is
done with an adjustable seat.
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Figure C4: Top view of concept 4
Figure C5: Side view of concept 4
Concept 5: Fully Faired Recumbent Bicycle with Bubble Canopy
Concept 5 integrates Long wheelbase, two sided FWD, pedals turn with front wheel, recumbent
bicycle, large gears, adjustable boom, low center of gravity, carbon frame, fully faired for sprint
and endurance race (see Figure C6 and Figure C7, below). The steering being attached to the
pedals will help aid in the spring allowing the rider to pull up on the handlebars as they push
down on the pedals simulating a sprint on an upright bicycle.
Figure C6: Drive Train for concept 5
← Direction of travel
Video camera ↓
← Video glasses
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24
Figure C7: Side view of concept 5
Top-level final design evaluation and Selection
The concepts listed above were evaluated in a concept scoring matrix (see Table 2, below),
using the Vike Trike II as a datum. Scoring is from a 1 - 5 range, with scores meaning:
1 – Very inferior
2 – Inferior
3 – Acceptable
4 – Superior
5 – Much superior
Table C1: Concept scoring matrix Datum Concept 1 Concept 2 Concept 3 Concept 4 Concept 5
Performance
Top speed 3 5 1 4 4 5
Frame Strength 3 3 1 3 3 3
Crash recovery 3 2 5 3 1 2
High-speed stability 3 5 5 4 2 2
Straight line
aerodynamic
efficiency
3 5 1 3 2 2
Partial fairing
removal for rider
entry and exit
3 4 5 3 3 4
Cost
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25
Stay under budget 3 4 5 3 1 1
Life in Service
HPV to last through construction,
testing, and
competition
3 2 1 3 3 3
Rider Safety
Visibility 3 5 5 4 2 4
Fairing Strength 3 4 1 3 4 4
Total Score 30 39 30 33 25 30
Concept 1 is nine points above the datum, and six points above the nearest competitor. Each of
the ten main design requirements is given equal weight in this scoring matrix, so the minimum
possible score is ten points and a maximum possible score is 50 points.
Dividing the total score by the number of requirements gives an average score range of one
through five. This is convenient because the same scoring range listed above can be used.
Therefore, Concept 1 is very close to a superior rating. Likewise, Concepts 2, 3, and 5 are close
to an acceptable rating and Concept 4 is half way between poor and average.
The concept scoring matrix clearly indicates that team will be manufacturing Concept 1: the
short wheelbase, recumbent, bike, with rear wheel drive, an adjustable boom, a fixed seat, and
a fully enclosed torpedo-shaped fairing with landing gear to be used in the endurance and
sprint races. With a commitment to working on Concept 1, each of the product sub-functions
requires detailed design decisions beyond the top-level concepts.
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26
Appendix D: Product Design Specification
Table D1: High priority product design specifications Table
Criteria
Requirements Primary
Customer
Measurement Metric Target Target Basis Verification Method
Performance Top speed PSU-HPV Team Top speed in male and
female sprint races
mph >45 mph Competition
research
Vehicle Time trial research
Braking ASME HPVC
Judges
Stopping distance at
15mph
Feet =< 20ft Competition rules Vehicle testing
Strength ASME HPVC
Judges
Frame safety factor Non-dimensional >1.5 Competition
research
Design analysis
Strength PSU-HPV Team Fairing strength Flexure modulus Greater than or
equal to 2007 PSU
HPV fairing
Competition
research
Materials testing
Crash recovery PSU-HPV Team Time to self-upright Seconds < 15s Competition
research
Vehicle testing
Turning radius ASME HPVC
Judges
Turning ability Radius in feet < 25ft HPVC rules Vehicle testing
High-speed stability PSU-HPV Team Vehicle does not wobble
uncontrollably at straight
line speeds > 20mph
Steering axis
rotation in
degrees
< 5deg Competition
research
Vehicle testing
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27
Criteria Requirements Primary
Customer
Measurement Metric Target Target Basis Verification Method
Performance Straight line
aerodynamic efficiency
PSU-HPV Team Coefficient of drag Non-dimensional <=.14 Frontal area is an
improvement upon
Vike Trike II fairing
Theoretical verification with
CFD and achieved with wind
tunnel testing
Partial fairing removal
for rider entry and exit
PSU-HPV Team Rider change out time Seconds <60s Improve upon Vike
Trike II fairing
Time trial testing
Documentation Fulfill ME 492/493
Class Requirements
PSU-HPV Team Score on capstone
related reports
Grade A ME 492/493 class
syllabus
Inspection of class grade
Life In Service HPV needs to last
through construction,
testing, and HPV
Challenge.
PSU-HPV Team Life of bike Months > April 2008 Bike must last until
HPV Challenge is over
Inspection
Table D2: Medium priority product design specifications Criteria Requirements Primary
Customer
Measurement Metric Target Target Basis Verification Method
Aesthetics Visual appeal ASME HPVC
Judges
Frame appearance and
competition design
presentation
Points, subject to
judges
interpretation
30 points Competition rules Review points awarded at
competition
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28
Criteria Requirements Primary
Customer
Measurement Metric Target Target Basis Verification Method
Performance Maintenance PSU-HPV Team Industry standard bike
tools
Common bike
tool sizes,
percent
= 100% Competition
research
Vehicle Time trial research
Maintenance PSU-HPV Team Ease of access # of parts to
remove to get to
desired part
<= 1 part Direct comparison
to standard
recumbent bikes
Solid modeling, vehicle
testing
Light weight PSU-HPV Team Vehicle assembly lbs < 50 lbs Improve upon
Vike Trike II fairing
and frame
Measurement with scale
Cost Stay under budget PSU-HPV Team Stay under budget with
material and fabrication
cost
Dollars > Budget Competition
research
Expenditure accounting
Safety Rider safety PSU-HPV Team Visibility Degrees of
vertical and
horizontal view
Horizontal > 150
degrees Vertical >
60 degrees
Rider preference Measurement
Fairing Strength Modulus of
elasticity
>= Vike Trike II Experience of
previous fairings’
adequate strength
Vehicle testing
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Table D3: Low priority product design specifications Criteria Requirements Primary
Customer
Measurement Metric Target Target Basis Verification Method
Ergonomics Rider comfort PSU-HPV Team Comfortable
temperature
Deg F > 65 deg Competition research Vehicle testing
Ventilation Energy out, Watts Energy out =
Energy in
Competition research Vehicle testing
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30
Appendix E: Frame Analysis
Summary Section
FEA was performed with I-DEAS 5 to analyze stress, strain, displacement, modal frequency, and
weight in the Vike Bike frame. Nine FEA optimizations were performed to find geometry and
commercially available tube sizes that would give the highest stiffness and lowest weight while
making sure to stay above the required safety factor of 1.5.
Loading conditions were modeled assuming worst case scenario loading and a simplified beam
mesh (see Figure E1), as described by Furniss and others (2007). The Vike Bike was modeled to
show compliance with ASME roll bar standards, no yield or fracture in a top loading of 485lbf or
a side loading of 260lbf (Interpretation of Rollover/side Protection Rules for 2008 HPVC
Competition, 2008). A materials selection analysis determined that Aluminum 6061 would be
used instead of 4140 steel or Titanium. The final optimization results are presented in Table E1
for stress (psi), factor of safety against material failure and yielding. Table E2 shows the final
optimization results for modal frequency (Hz) and weight (lbf). Material displacement is shown
in Table E3 and indicates that the largest rider will not come into contact with the ground
during a rollover condition.
Table E1: Stresses and factors of safety in different loading conditions
Final
Optimization
Top Load
Side Load – Frame Side Load –
Fork
Maximum Von
Mises stress (psi)
7330 18500 9810 Fatigue Factor of saftey
(ASME/Gerber)
Yield strength
(psi)
35000 35000 35000 Main tube Boom
Factor of safety
against yield
4.8 1.9 3.6 4.1/3.9 1.8/1.7
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Table E2: Frame modal frequencies and weight
Final
Optimization
Mode 1 (Hz) 20
Mode 2 (Hz) 46
Mode 3 (Hz) 62
Mode 4 (Hz) 72
Mode 5 (Hz) 100
Frame
Volume (in^3)
133
Frame Weight
(lbf)
13
Table E3: Displacement and strain due to top and side loading conditions. x indicates not applicable
measurements.
Top Load Side load
Maximum elastic deformation (in) 2.31E-04 7.20E-04
Critical location displacement X (in) -1.64E-01 x
Critical location displacement Y (in) -6.50E-02 x
Critical location displacement Z (in) x x
Beginning clearance 0.83 0.83
Ending clearance 7.65E-01 0.83
Formulation Section
Given: Model of the Vike Bike I and II, reported by 2007 PSU HPV Team in their ASME Design
report, show rider weight of 100lbf at the seat tube bends, 1680in*lbf moment about the z axis,
and a 1320 lbf moment about the y axis (see Figure E1, below). Vike Trike I and II displacement
results are listed in Table E4. The ASME “Interpretation of Rollover/side Protection Rules for
2008 HPVC Competitions” states a top load of 485 lbf and a side load of 260 lbf (see Figure E2),
where the loads are applied independently.
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Figure E1: FEM with Boundary Conditions for the Vike Trike II.
Table E4: Comparison of Stress and Displacement for Vike Trikes I and II.
Figure E2: Loading requirements determined by ASME
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33
Find:
a) Model 2008 Vike Bike design and determine the maximum stress and displacement
using 6061 Aluminum. Show validity of model through convergence. Compare results to
Vike Trike II.
b) Find maximum stress and displacement using the same model as in part (a), using
Titanium and 4140 steel. Compare results.
c) Perform a modal analysis of the three models in part (b). Compare results.
d) Select frame material.
e) Using ASME top and side loads, show that the roll bar is acceptable and that there is
no permanent deformation or fracture on either the roll bar or the vehicle frame. Find
factor of safety against fatigue failure.
Assumptions:
The fork, frame, and boom are all one piece.
Dropouts, wheels, headset, cranks, and bottom bracket are not modeled because they
are design to withstand bicycle loading.
ASME top and side loads are not considered cyclical and are not used in a fatigue
analysis.
Rider weight is a point load in the seat tube bends.
Solution:
a)
Geometry –
The geometry was created with as a 3-D wireframe sketch in Solid Works and imported into I-
deas 5. Beam cross sections were keyed in for the seat tubes, roll bar, head bar, boom, main
tube, forks, and fork bends. Where the tube and main tube come together and where the head
tube and steer tube come together were both modeled as beams with the outer diameters of
the bigger beam and the inner diameter of the smaller beams.
Mesh-
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34
Meshes were created using the beam mesh option in I-deas. Four meshes using 6061 Aluminum
for the body and generic isotropic steel were created. Different element sizes were used to
show the solutions convergence. Meshes 1 through 4 had 113, 161, 257, and 283 elements
respectively
Boundary Conditions -
To compare stress and displacement to Vike Trike II, similar loading and restraints were
employed to those shown in Figure E1, above. Two point loads of 100lbs each were applied to
the seat tube bends. The rear dropouts were fixed from translation, and the front dropouts
were fixed from translation in the y and z axis. A boundary conditions set was then created. This
was all accomplished under the Boundary Conditions task-icon, heat transfer mode. All of the
constraints and forces included in the boundary conditions set can be seen in Figure E3.
Figure E3: Vike Bike I frame and boundary conditions for dynamic loading.
Results -
A solution set was created for the models with their boundary condition sets, and the models
were solved under the Model Solution task-icon. Table 5E5, below, shows the results for
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maximum Von Mises stress, x displacement, y displacement, z displacement, and strain energy
for each of the meshes. The stress and displacement results converged almost immediately
(See Figures E4 and E5). The 283 element mesh was optimized to reduce the strain energy
encountered from the 257 element mesh (see Figure E6).
Table E5: Maximum Von Mises stress , displacement, and strain energy for each model.
Elements
Maximum Von Mises
Stress (psi) X (in) Y (in) Z (in)
Strain Energy
(in*lbf)
113 2.36E+04 8.12E-02 9.29E-02 1.40E-01 3.25E+00
161 2.36E+04 8.12E-02 9.29E-02 1.47E-01 3.87E+00
257 2.36E+04 8.12E-02 9.31E-02 1.40E-01 1.10E+00
283 2.36E+04 8.12E-02 9.31E-02 1.40E-01 6.51E-01
Figure E4: Convergence of Von Mises Stress
0.00E+00
5.00E+03
1.00E+04
1.50E+04
2.00E+04
2.50E+04
0 50 100 150 200 250 300
Maximum Von Mises Stress
(psi)
Number of Elements
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36
Figure E5: Convergence of Displacement
Figure E6: Convergence of Strain Energy
0.00E+00
2.00E-02
4.00E-02
6.00E-02
8.00E-02
1.00E-01
1.20E-01
1.40E-01
1.60E-01
0 50 100 150 200 250 300
Displacement (in)
Number of elements
X (in)
Y (in)
Z (in)
0.00E+00
5.00E-01
1.00E+00
1.50E+00
2.00E+00
2.50E+00
3.00E+00
3.50E+00
4.00E+00
4.50E+00
0 100 200 300
Strain Energy (in*lbf)
Number of elements
Strain Energy (in*lbf)
Page 40
37
b)
Mesh-
Meshes were created using the 283 element beam mesh used in part (a). Meshes 1 through 3
were made with 4140 steel, 6061 aluminum, and typical titanium bodies, while maintaining the
fork as generic isotropic steels. Tube sizes were kept the same for each mesh.
Boundary Conditions -
Boundary conditions were the same as in part (a).
Results -
A solution set was created for the models with their boundary condition sets, and the models
were solved under the Model Solution task-icon. Table E6 shows the results for maximum Von
Mises stress, x displacement, y displacement, z displacement, and strain energy for each of the
meshes. The Vike Trike II stress and displacement results are reproduced for ease of
comparison. Titanium versus aluminum evaluation is included as well and shows a titanium
displacement of 80% that of Aluminum. Figure E6 shows the location of the maximum Von
Mises stress in the frame and the fork, for each model. Figure E7 shows the location of the
maximum displacement for each model.
Table E6: Tabulated results of stress and displacement in each body.
4140 Steel Al 6061 Titanium (Typical) Vike Trike II Ti vs Al (%)
Maximum Von Mises
Stress (psi) 2.34E+04 2.52E+04 2.46E+04 8.29E+03 97.62
Max. Disp. X (in) 5.50E-02 8.12E-02 5.53E-02 7.96E-02 68.10
Max. Disp. Y (in) 4.32E-02 9.31E-02 6.55E-02 2.06E-01 70.35
Max. Disp. Z (in) 7.50E-02 1.40E-01 1.10E-01 1.57E-01 78.57
Displacement
Magnitude (in) 8.45E-02 1.53E-01 1.22E-01 2.71E-01 79.74
Strain Energy (in*lbf) 6.67E-01 6.51E-01 1.24E+00
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38
Figure E7: Maximum Von Mises Stress locations for (clockwise from top left)
4140 steel, 6061 aluminum, and typical titanium.
Page 42
39
Figure 8H: Maximum displacement location for (clockwise from top
left) 4140 steel, 6061 aluminum, and typical titanium
c)
Mesh-
Meshes were the same as the meshes used in part (b)
Boundary Conditions -
Restraints were the same as those used in parts (a) and (b). Boundary condition sets were made
under normal linear dynamics, Lanzcos method.
Results -
A solution set was created for the models with their boundary condition sets, and the models
were solved under the Model Solution task-icon.
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40
Table E7 contains the results for the first five modes in each model. The bike weight is also
included for each type of material. It can be seen that 4140 is too heavy to be used effectively
in the human powered vehicle. Aluminum 6061 provides the lightest bike weight by far, with
similar modes to those found in 4140 and Titanium. Titanium offers 80% of the total deflection
than that of Aluminum with similar tube sizes.
Table E7: Lanzco’s method
Modal analysis 4140 Steel Al 6061 Titanium (Typical)
Mode 1 (Hz) 9.85E+00 1.12E+01 1.03E+01
Mode 2 (Hz) 3.13E+01 2.91E+01 3.09E+01
Mode 3 (Hz) 3.85E+01 3.76E+01 3.78E+01
Mode 4 (Hz) 7.39E+01 7.23E+01 7.21E+01
Mode 5 (Hz) 8.18E+01 9.03E+01 9.34E+01
Total Weight (lbf) 49.5 17.25 29
Densities from
eFunda
d)
The results (see Table E8) indicate that an aluminum frame with the same tube sizes is 56-60%
the weight of a titanium frame, and 35% of the weight of the steel frame. Comparison of the
Vike Bike (using aluminum) and the Vike Trike II shows the Bike with 56% of the total
displacement than that of the Vike Trike. The Bike has 50% more stress which lowers the factor
of safety from 4.46 to 3.06. With the light weight of aluminum, adequate factor of safety, low
cost, and ease of manufacture, it is recommended that Aluminum 6061 be used for the Vike
Bike I frame. Table E8 shows a comparison of the Vike Bike against the Vike Trike II.
Table E8: Comparison of Vike Bike and Vike Trike II
Al 6061 Bike Vike Trike II Al. Bike vs. Trike (%)
Maximum Von Mises Stress (psi) 1.21E+04 8.29E+03 145.96
Max. Disp. X (in) 8.12E-02 7.96E-02 102.01
Max. Disp. Y (in) 9.31E-02 2.06E-01 45.19
Max. Disp. Z (in) 1.40E-01 1.57E-01 89.17
Displacement Magnitude (in) 1.53E-01 2.71E-01 56.47
Factory of Safety 3.06E+00 4.46E+00 68.51
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41
e)
Geometry –
The geometry was changed slightly to accommodate ease of manufacturing and new fork
models.
Mesh -
Meshes were kept 283 +/- 20 elements.
Boundary Conditions -
For fatigue, the dynamic loading listed above was broken into mean and alternating loading
conditions. A top loading and a side loading was created as per ASME rollbar standards. ASME
guidelines specify that the fork and dropouts must be free from translation. This restraint set
was used for all models. A modal boundary condition set was created using Lanzco’s method.
Results –
A sample (Final Optimization) calculation for fatigue in the Boom is provided:
Fatigue analysis - Boom
*All tables and equations in the fatigue analysis section refer to Mechanical Engineering Design, 7th ed., by Shigley
ksi Ultimate strength in 6061-T6 aluminium
Yield strength in 6061-T6 aluminum
Endurance strength in 6061-T6 aluminium
Marin Factors
Machined parameters from table 7-4
Sut 38
Sy 35ksi
Seprime 0.504Sut
a 2.70
Page 45
42
Equation 7-18
Surface factor ka
Boom diameter
Equivalent diameter, equation 7-23
Equation 7-19, for diameter .11<=d<=2in
Size factor kb
Loading factor for bending, equation 7-25
Temperature factor at 20 deg C, table 7-6 and equation 7-27
95% reliability factor from Table 7-7
Equation 7-17
ksi
Modified endurance factor
Load line
Factor of safety against first cycle failure
b 0.265
ka a Sutb
ka 1.03
d 1.75in
de0.370d
in
kb 0.879de0.107
kb 0.921
kc 1
kd 1
ke 0.868
Se ka kb kc kd ke Seprime
Se 15.763
Se 15.682ksi
m 9.79ksi
a 7.65ksi
a
m
0.781
ny
Sy
a m
ny 2.007
Page 46
43
Fatigue in the main tube was analyzed with a similar method but with slightly different Marin
factors to due to the different tube sizes.
The results for each optimization, including the original and modified geometry, are included
below. Table E9 shows the maximum stresses and factors of safety for the specified loading
conditions. Table E10 shows the modal frequencies and weight for each optimization model.
The results in Table E11 show that the maximum elastic strain and displacement are within the
ASME specified requirements and do not endanger the rider.
Table E9: Maximum stresses and factors of safety for specified loading conditions First Approximation Top Load -
frame
Side load - frame Side load -
fork
Dynamic -
frame
Dynamic - fork
Maximum Von Mises stress (psi) 4.42E+03 1.74E+03 4.28E+04 1.21E+04
Yield strength (psi) 3.50E+04 3.50E+04 1.02E+05 3.50E+04
Factor of safety against yield 7.92 20.1 2.4 2.9
Optimization 1
Maximum Von Mises stress (psi) 4.43E+03 1.96E+04 4.02E+04 9.26E+03 1.85E+04
Yield strength (psi) 3.50E+04 3.50E+04 1.02E+05 3.50E+04 1.02E+05
Factor of safety against yield 7.9 1.8 2.5 3.8 5.5
Optimization 2
ASME-Elliptic Failure Criteria, Table 7-11
Factor of safety against fatigue failure
Gerber Failure Criteria, Table 7-10
Factor of safety against fatigue failure
nf1
a
Se
2m
Sy
2
1
2
nf 1.778
nf1
2
Sut ksi
m
2
a
Se
1 12 m Se
Sut a ksi
2
1
2
nf 1.67
Page 47
44
Maximum Von Mises stress (psi) 6.18E+03 2.08E+04 4.15E+04 9.26E+03 1.86E+04
Yield strength (psi) 3.50E+04 3.50E+04 1.02E+05 3.50E+04 1.02E+05
Factor of safety against yield 5.7 1.7 2.5 3.8 5.8
Top Load -
frame
Side load - frame Side load -
fork
Dynamic -
frame
Dynamic - fork
Optimization 3
Maximum Von Mises stress (psi) 5.63E+03 1.79E+04 3.87E+04 2.06E+04
Yield strength (psi) 3.50E+04 3.50E+04 1.02E+05 3.50E+04
Factor of safety against yield 6.2 2.0 2.6 1.7
Optimization 4
Maximum Von Mises stress (psi) 1.05E+04 1.79E+04 3.87E+04 Fatigue Factor of saftey
Yield strength (psi) 3.50E+04 3.50E+04 1.02E+05 Main tube boom
Factor of safety against yield 3.3 2.0 2.6 2.54/2.4 3.4/3.2
Optimization 5
Maximum Von Mises stress (psi) 5.36E+03 1.55E+04 3.85E+04 Fatigue Factor of saftey
Yield strength (psi) 3.50E+04 3.50E+04 1.02E+05 Main tube boom
Factor of safety against yield 6.5 2.3 2.6 2.9/2.7 3.5/3.3
Optimization 6
Maximum Von Mises stress (psi) 5.35E+03 2.05E+04 4.27E+04 Fatigue Factor of saftey
Yield strength (psi) 3.50E+04 3.50E+04 1.02E+05 Main tube boom
Factor of safety against yield 6.5 1.7 2.4 3.0/2.8 3.5/3.3
Optimization 7
Maximum Von Mises stress (psi) 7.32E+03 1.95E+04 3.70E+04 Fatigue Factor of saftey
Yield strength (psi) 3.50E+04 3.50E+04 3.50E+04 Main tube boom
Factor of safety against yield 4.8 1.8 0.9 3.80/3.6 2.5/2.4
Final Optimization
Maximum Von Mises stress (psi) 7330 18500 9810 Fatigue Factor of saftey
(ASME/Gerber)
Yield strength (psi) 35000 35000 35000 Main tube Boom
Factor of safety against yield 4.8 1.9 3.6 4.1/3.9 1.8/1.7
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Table E10: Modes and weight for each model Origin
al
Optimizatio
n 1
Optimizati
on 2
Optimizati
on 3
Optimizati
on 4
New
Geometry
Optimizati
on 6
Optimizati
on 7
Final
Optimizati
on
Mode 1 (Hz) 11 17 20 21 21 21 20 19 20
Mode 2 (Hz) 29 33 33 38 36 36 35 32 46
Mode 3 (Hz) 38 36 38 40 39 39 40 49 62
Mode 4 (Hz) 72 69 70 82 80 75 70 69 72
Mode 5 (Hz) 90 93 96 115 111 112 111 100 100
Frame
Volume (in^3)
178 160 128 128 138 137 128 131 133
Frame Weight
(lbf)
17 16 12 12 13 13 12 13 13
Table E11: Displacement and strain due to top and side loading conditions. x indicates not applicable
measurements.
Top Load Side load
Maximum elastic deformation (in) 2.31E-04 7.20E-04
Critical location displacement X (in) -1.64E-01 x
Critical location displacement Y (in) -6.50E-02 x
Critical location displacement Z (in) x x
Beginning clearance 0.83 0.83
Ending clearance 7.65E-01 0.83
Analysis references:
Shigley, J.E.. 2004. Mechanical Engineering Design. 7th ed. New York: Mcraw-Hill
American Society of Mechanical Engineers. 2008. Interpretation of Rollover/side Protection
Rules for 2008 HPVC Competitions. http://files.asme.org/asmeorg/Events/Contests/
HPV/13615.pdf (10 March 2008).
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Appendix F: Biomechanical Testing
Summary Section
For the finite element model of the frame it is important to apply accurate forces insuring that
the frame is not overbuilt. This helps cut the overall weight of the Vike Bike I. A top speed
analysis will also be more accurate knowing the actual forces and power the riders are able to
subject the bike to. These forces are measured in the x, y, and z directions using a PCP
Piezoelectric force transducer model U206A203 that is attached to the Vike Trike II pedal as
seen in Figure F1. A Model Shop low speed laser tachometer was also used to measure the
cadence for each rider.
Figure F1: PCB Force Transducer bicycle pedal adapter
The testing was performed on the Vike Trike II with the use of LABView and a NI-9233 data
acquisition device. The PDS states that the Vike Bike I will reach a top speed greater than 45
miles per hour. With this testing the Vike Bike I’s top speed can me more accurately calculated.
The PDS also lists a light overall weight of the Vike Bike I. The biomechanical testing will help
the design team design the frame so that it is light and strong enough to withstand the loading
each rider will produce while riding.
The PCB force transducer’s output signal is a voltage in each direction x, y, and z. A conversion
factor is determined through testing and calibration from PCB allowing the conversion from mV
to Newton or pound force. The signal output for the laser tachometer is also voltage that can
be tabulated using the virtual instrument. The data can then be graphed comparing the
resultant force for x, y, and z to the rider cadence. Below a table was constructed showing the
rider maximum force and cadence.
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47
Table F1: Rider force output, cadence
Rider Max Force (Lbf) Average Force (Lbf) Cadence (rpm) Max Power (Hp) Average Power (Hp)
Ben 104.50 40.08 98.40 1.12 0.43
Bryan 105.78 30.12 90.00 1.04 0.30
Chantelle 96.36 42.39 72.00 0.76 0.33
Erik 136.10 52.37 88.00 1.31 0.50
Kenneth 163.47 36.16 78.00 1.39 0.31
levi 82.40 25.05 90.00 0.81 0.25
Formulation Section
Given: Figure F2
Figure F2: Rider resultant force and cadence output for 5 seconds.
Find:
-Moments about center of bottom bracket.
Assumptions:
-Ignore losses in pedal connection and bottom bracket.
Solution:
Analysis Reference: Bolen, Ben and Bryan Voytilla. 2008. ME 411 Final Lab Report
Force 104.5lbf
crank_radius 175mm
Mbb Force 2 crank_radius
Mbb 119.997ft lbf
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48
Appendix G: Braking Analysis
The Vike Bike’s breaking performance is described by the distance required to come to a
complete stop at a given vehicle velocity. This distance is defined in Equation G1 (Wilson, 2004):
𝑆 =𝑉2
20(𝐶𝐴+𝐶𝑅) (Eq. G1)
where S is the distance required to stop in meters, V is the vehicle velocity in meters per
second, CA is the coefficient of adhesion for the material the vehicle is breaking on, and CR is the
coefficient of rolling resistance for the vehicle and is s function of vehicle weight. Figure G1
demonstrates that the Vike Bike is able to achieve a stopping distance of 8.33 feet while
traveling at a velocity of 15 mph, given concrete with a CA of 0.8 and a CR of 0.035.
Figure G1: log- log scale plot of stopping distance vs. vehicle velocity for the 2008 Vike Bike
10, 3.70
15, 8.3320, 14.82
25, 23.1530, 33.34
40, 59.2750, 92.61
1
10
100
1000
10 100
Sto
p D
ista
nce
(Fe
et)
Velocity (MPH)
Concrete (Dry)
Concrete (Wet)
Gravel, Rolled
Sand, Loose
Ice
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49
Appendix H: Top Speed Analysis
Summary Section
Accurately demonstrate that the desired top speed of 45 mph can be achieved given the Vike
Bike I’s drive train. The Vike Bike I’s top speed analysis incorporates the biomechanical rider
force output data. These realistic forces can be applied to energy and gearing calculation to
determine the top speed that can be achieved given the drive train of the Vike Bike I. The Vike
Bike I drive train is based on the conventional drive train of a bicycle with a few exceptions in
gear selection. Two custom bicycle chain rings 65 tooth and 75 tooth were fabricated and
donated for use in the spring competition. The PDS states that a top speed of greater than 45
mph will be achieved during the HPVC sprint competition.
Given the tabulated results used in Appendix F: Biomechanical testing the forces are used to
calculate the overall achievable speed for the Vike Bike. Maximum speed: 45.28 Miles/hour
While calculating the top speed all forces exerted on to the Vike Bike I are included in the
overall attainability equation.
Formulation Section
Given: The current drive train setup on the PSU Vike Bike I human powered vehicle in Figure H1.
Air density, frontal area, coefficient of drag, mass of Vike Bike I is 1.266 kg/m3 , 0.535m2 , 0.14,
and 28 Kg respectively.
Figure H1: PSU Vike Bike I drive train.
Find: What is the theoretically maximum achievable speed?
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50
Assumptions: Speed is achieved at sea-level
Solution:
Top Speed:
Frictional Force:
Tire_Diameter 700mm
Tire_Circumferance Tire_Diameter
Crank_Length 175mm
Cadence90
min
efficiency 0.90
ncrank 75
nwheel 11
Wheel_speed Cadencencrank
nwheel
efficiency
Wheel_speed 9.2051
s
Max_Speed Tire_Circumferance Wheel_speed
Max_Speed 45.28mile
hr
fkinetic_friction 0.0021
Frictional_Force Normal_Forcefkinetic_friction
Frictional_Force 2.585N
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Air Drag:
Applied Force:
The attainability equation relates force balance of the mechanical force produced by the rider
and the friction and aerodynamic drag force applied to the Vike Bike I. A positive value
indicated a larger rider mechanical force than the drag force due to aerodynamics and friction
thus, proving a speed achievable.
Air_density 1.226kg
m3
Frontal_area 0.535m2
Cd 0.14
Air_drag1
2Cd Air_density Frontal_area Max_Speed
2
Air_drag 18.812N
Max_Force 104.5lbf
Max_Force Crank_Length
81.347J
Wheel_torque
ncrank
nwheel
efficiency
Wheel_torque 10.738J
Applied_ForceWheel_torque
Tire_Diameter
2
Applied_Force 30.679N
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52
This top speed formulation was tested at the ASME competition where the Vike Bike race team
was able to reach an unofficial speed of 44 Mph in the sprint race with an allowable run up of
600 meters.
Attainability Applied_Force Air_drag Frictional_Force( )
Attainability 9.282 N
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Appendix I: Turning Analysis
Summary Section
ASME rules state that a vehicle must be able to turn within a 25ft radius. A geometric analysis
was performed to see how many degrees the fork of Vike Bike I must turn to fit within this
circle. Through solid modeling, it was found that the maximum amount that the steering tube
could rotate was 31.88 degrees. Since the steering tube and fork are connected directly, this is
also the maximum amount that the fork is able to turn. With this information, the minimum
achievable turn radius (in feet) was calculated. The results of the analysis listed below:
a) Turning angle required to achieve 25ft turn radius – 10.6 deg
b) Turning radius with a 31.88 degree turning angle – 8.7 ft
Each situation was modeled as a worst-case scenario. After starting the initial turn, the angle
required to continue the turn will decrease. Leaning into the turn also decreases the turning
angle required. Accounting for continuing a turn and leaning into account, the amount of
turning angle and the turning radius will decrease. Therefore, the design meets and exceeds
ASME standards.
Formulation Section
Given: Figure I1 shows Vike Bike I having a wheelbase of 54.95 inches. The maximum angle that
the steer tube can turn without hitting the fairing is 31.88 degrees, as shown in Figure I2.
Figure I1: Top view of the Vike Bike. The wheelbase measurement is
important in the view plane (i.e. Delta X) only.
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Figure I2: When the steer tube has reached its maximum swing, the angle
between the steer tube and the main tube is 31.88 deg, measured from the
top view.
Find:
a) The angle that the fork must turn to achieve the ASME required turn radius of at least 25ft.
b) The turn radius when the steer tube is at 31.88 degrees.
Assumption:
1. Leaning when riding improves the turn radius, and not leaning corresponds to lower
speed biking. Performing the analysis without taking leaning into effect will be
considered as a worst case scenario.
2. Starting the turn requires more of a turning angle than continuing the turn. Therefore,
only the initial angle will be considered as a worst case scenario.
Solution:
a) Figure E3 provides a sketch of the system at the start of a low speed turn.
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55
Figure I3: Sketch of the wheelbase (solid line) and the 25 foot circle with
radius (dashed line). All dimensions are in inches.
The front wheel is coincident with the curve (see fig I3). To turn the Vike Bike in the circle, the
front wheel must be turned at an angle from the frame until it is tangent with the circle. A right
triangle is created from fig F3 and is shown.
Figure 4I: Sketch of tangent line (solid line) and right triangle. Hyp is the
hypotenuse and the radius of the circle, b is the wheelbase, and a is the
desired angle.
By geometric association, it can be seen that the desired angle is the same angle in the right
triangle (fig’s 4I & E4). Angle a is found using equation I1
(Eq. I1)
Substituting values for b and hyp into eqn I1 yields the desired angle.
a asin54.95
300
a asinb
hyp
a 10.6deg
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56
Desired angle for the ASME prescribed minimum turn radius of 25ft.
b)
A sketch of the system with the given information is provided in figure I5.
Figure I5: Sketch of the wheelbase and turn circle when the fork is turned to
its maximum angle.
Solving equation I1 for the hypotenuse gives:
(Eq. I2)
Substituting the values of a and b into equation I2 yields:
Converting the turn radius to feet yields:
For the turn radius when the steering tube is at an angle of 31.88 degrees.
hypb
sin a( )
hyp54.95in
sin 31.88( )
hyp 104.044in
hyp 8.7ft
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Appendix J: Strain Gauge Testing
The ASME roll-bar guidelines for 2008 state that each team is granted points for demonstrating
that their roll-bar is able to withstand a vertical load of 485-lb 8° off of vertical and a side load
of 260-lb at shoulder height (Figure J1). Each team is able to demonstrate verification by
physical testing, computational analysis, and safety. Failure to demonstrate the loading
requirements in any category will result in a deduction of points for that team.
Figure J1: ASME Roll-bar analysis loading criteria top load of 485-lb and side load of 260-lb
Strain gauges are placed in the areas’ of interest as pointed out in the frame finite element
analysis section and also seen in Figures J2 and J3. The vertical physical loading is
demonstrated in figure J4 with the Vike Bike restrained at the front and rear axils and tilted 8°
off of horizontal. A load of 492-lb was then hung from the middle of the roll-bar.
Figure J2: Strain gauge placement for top loading criteria (485-lb)
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Figure J3: Strain gauge placement for side loading criteria (260-lb)
Figure J4: Strain gauge testing for the top loading roll-bar criteria (492-lb)
The side load of 265-lb was applied to the side of the roll-bar while the front and rear axles are
restrained (figure J5).
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59
Figure J5: Strain gauge testing for the side loading roll-bar criteria (260-lb)
The final results are tabulated in table J1 and compared to the theoretical results from the finite
element analysis. Completing this demonstration of loading the bike resulted in zero points
deducted for the analysis, testing, and safety category of the roll-bar strength verification thus,
proving that the Vike Bike will be able to withstand a roll-over.
Table J1: Strain gauge results. Side Load Top Load
Strain Gauge Result (maximum elastic strain)
Finite Element Analysis (maximum elastic strain)
Strain Gauge Result (maximum elastic strain)
Finite Element Analysis (maximum elastic strain)
0.00079 0.00072 0.00031 0.000231
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Appendix K: Fairing Aerodynamic Analysis
Summary
The goal is to verify that the drag forces have been reduced when compared to the Vike trike
‘06/07 fairing. By manipulation of the shape of the fairing, specifically in the planar view as
shown in figure 1I, the coefficient of drag and the frontal area will be reduced when compared
to the Vike Trike II.
Frontal Area= 864 in2
Coefficient of drag (Cd) = 0.06
The frontal area and Cd of the 2008 fairing have been verified as being reduced compared to
the 2007 Fairing.
Formulation
Given:
Two models, shown in Figures K1 and K2, are available for analysis. A solid model of the Vike
Bike’s external surface created in SolidWorks 2007 is can be used for theoretical analysis while
a physical model has been constructed and can be used to collect experimental data.
Figure K1: 3D solid model of the Vike Bike fairing
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61
Figure K2: Completed fairing and bike assembled
Find:
a) The frontal area
b) The coefficient of drag
Assumptions:
-External flow is normal to the frontal area of the fairing.
Solution:
a) The frontal area of the ‘06/07 fairing is found using the SolidWorks 2007 tool “Section
Properties” . The frontal areas of both fairings can be seen in the Figures below.
Figure K3: 2006/07 Fairing frontal area Figure K4: 2008 Fairing frontal area
886in2 864in2
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The 2008 faring has a frontal area of 864in2 while the 2006/07 fairing has a larger surface area
of 886in2. This gives a 2.5% reduction in frontal area.
b) The coefficient of drag was found using two methods, theoretical and experimental. The
theoretical Cd value was found using CFD while the experimental value was found using a wind-
tunnel test facility provided by Freightliner. Both methods are presented below.
An idealized 3D model of the fairing was imported into the CFD program. The body seams and
wheel cutouts were omitted in order to simplify the meshing procedure. Pressure and velocity
plots for a 15mph external flow are shown in FigureK5. Table K1 shows the results of the CFD at
15 and 30mph.
Figure K5: Pressure plot at 15mph (left), velocity plot at 15mph (right)
Table K1: Results from CFD
Vehicle velocity Coefficient of Drag Net drag force
15mph .084 0.14 lbf
30mph .072 0.48 lbf
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63
The completed fairing was taken to the Freightliner wind-tunnel where it was also tested under parallel wind conditions. The wind-tunnel results are shown in Table K2 below.
Table K2: Results from CFD
Vehicle velocity (mph) Coefficient of Drag
39.21 .0507
39.36 .0539
The 2007 fairing Cd values are shown in the Table K3 below.
Table K3: Results from CFD
Vehicle velocity (mph) Coefficient of Drag
22.4 0.11
44.7 0.12
The values presented in the tables above are related by Equation K1.
𝐹 =1
2𝜌𝐶𝑑𝐴𝑉
2 Where: F = Drag force (Eq. K1)
𝜌 = fluid density Cd = Coefficient of drag A = Frontal Area V = Fluid or vehicle
velocity
Assuming similar fluid conditions. the aerodynamic characteristics of the two fairings can be compared using only the coefficient of drag and frontal area. This is shown in equations K2 and K3.
CdA (2007) = (0.11)(886 in2) = 97.46 in2 (Eq. K2)
CdA (2008) = (0.06)(864 in2) = 51.84 in2 (Eq. K3)
Finding the percent reduction of drag force.
97.46−51.84
97.46= 47% reduction of drag force (Eq. K4)
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Appendix L: Fairing Material Analysis
A fairing material was sought that will be stronger, more ductile, and lighter than the Vike Trike II fairing. A stronger and more ductile fairing is desired to protect the rider and absorb more energy during an impact, while an overall lighter fairing reduces rolling resistance and inertial forces. Seven samples were created to test fiber orientations of 0°- 45° and 0°- 90°, balsa wood and BaltekMat core, vacuum bagging and air drying, and two to three fiberglass layers (see Table L1). The samples were compared against the Vike Trike II fairing since it was tested during the 2007 ASME HPVC West competition and remained intact after multiple crashes. Each sample used S2 fiberglass and polyester resin with a balsa wood or BaltekMat core between the fiberglass layers. Due to budgetary constraints, carbon fiber was not considered as a potential solution because of its high cost relative to S2 fiberglass. To create a statistical average, five samples of each configuration were tested. Table L1: Sample configuration guide
Sample Layer Orientation Core Layup Method Layers
A (Vike Trike II) 0°-90° BaltekMat Air 3
B 0°-45° BaltekMat Vacuum 3
C 0°-90° BaltekMat Vacuum 2
D 0°-90° BaltekMat Vacuum 3
E 0°-90° Balsa (3/32") Vacuum 3
F 0°-45° Balsa (3/32") Vacuum 3
G 0°-45° Balsa (1/8") Vacuum 3
Strips of each sample were tested with a three point bend test (see Figure L1) according to ASTM standard D 790-97 (1998).
Figure L1: Three point bend test
The test data for each sample was used to find the modulus of elasticity in bending, weight per area, yield strength, and strain at yield. Modulus of elasticity in bending EH (psi) is calculated using EquationL1:
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65
𝐸𝐻 =𝐿3𝑚
4𝑏𝑑3
(Eq.L1)
Where L is the support span (in), b is the width of the sample (in), d is the thickness (in), and m is the slope of the tangent to the initial straight line portion of the load deflection curve (lbf/in). The stress of the outer fibers at midspan, S (psi) is determined to be:
𝑆 =3𝑃𝐿
2𝑏𝑑2(1 + 6
𝐷
𝐿 2
− 4 𝑑
𝐿
𝐷
𝐿 )
(Eq.L2)
P is the load at a given point along the load-deflection curve (lbf), D is the deflection of the center of the center of the beam. The strain in the outer fibers, R (in/in) is given as:
𝑅 =6𝐷𝑑
𝐿2
(Eq.L3)
Equations L1 through L3 were used to reduce the raw data obtained during the experiment (see Figs. L2 and L3). Figure 19 shows that only sample E has approximately the same bending modulus as sample A, while having a greater strain at yield. In Fig. L3, only sample E has consistently higher yield strength, while having a lower weight per area than sample A. Thus sample E is the only configuration that fulfills the requirement of being stronger, more ductile, and lighter than sample A, the Vike Trike II fairing. Table L2 is a direct comparison of the average values of sample E to sample A with percent differences. Sources of error are due to manufacturing variability, sample preparation, and measurement error.
700.00
800.00
900.00
1000.00
1100.00
1200.00
1300.00
1400.00
0.006 0.008 0.010 0.012 0.014 0.016 0.018
Be
nd
ing
Mo
du
lus
(ksi
)
Strain at Yield (in/in)
Sample A
Sample B
Sample C
Sample D
Sample E
Sample F
Sample G
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Figure L2: Bending modulus vs. strain at yield
Figure L3: Yield strength vs. Weight per area
Table L2: Comparison of average Vike Trike II and Vike Bike fairing properties
Weight per Area (lbf/ft^2) Strain at Yield (in/in) Yield Strength (ksi) Bending Modulus (ksi)
Sample A (2007 Vike Trike II) 0.50 +/- 0.02 0.011 +/- 0.001 10.8 +/- 0.8 1050 +/- 70
Sample E (2008 Vike Bike) 0.31 +/- 0.025 0.014 +/- 0.001 16 +/- 2.8 1100 +/- 100
% Difference from A -38 30 48 4.8
6.00
8.00
10.00
12.00
14.00
16.00
18.00
20.00
22.00
0.250 0.300 0.350 0.400 0.450 0.500 0.550
Yie
ld S
tre
ngt
h (
ksi)
Weight per area (lbf/ft^2)
Sample A
Sample B
Sample C
Sample D
Sample E
Sample F
Sample G
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Appendix R: Vehicle Stability
Stability
Recumbent bicycle stability depends on the wheel base and the wheel trail Figure 2R. A large
trail (more than 3.5”) and long wheelbase (in excesses of 60”) leads to better high speed
stability. A short wheel base (less than 60”) and a smaller trail (less than 3.5) allows for better
handling at low speeds. The Vike Bike was designed with a wheel base of 54.95” and a trail of
2.56”, as a compromise between high speed stability and low speed stability. The stability of
the Vike Bike was tested and verified in the 2008 ASME HPV Competition. During the
competition the PSU HPV race team was able to test the Vike Bikes high speed stability in the
sprint race. This was successful without any major crashes that were caused by the stability of
the bike. The PSU HPV race team did however find out that extra practice was needed to learn
how to ride a recumbent bicycle as opposed to a standard upright bicycle due to the relative
positions of the center of gravities of each.
Figure 2R: Vike Trike II Front wheel configuration
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Figure 1R: Vike Bike head tube angle design configuration
During the endurance race the low speed stability was tested by the PSU HPV race team and
found prior to competition that the rotation of the handlebars was inadequate and the side
read windows would need to be removed for this event. Upon further investigation the race
team found the fairing hard to maneuver due to rider unfamiliarity and decided to use only the
bottom half of the fairing. The bottom fairing would still provide the needed 10% frontal area
covering required for the race and also made the Vike Bike much more comfortable for the race
team to maneuver.
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Appendix M: Frame Design Drawing
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81
Appendix N: Fairing Design Drawings
The following drawings are derived from .dxf files that were given to OMSI. OMSI used the .dxf files to
write a machine code that was imported to a CNC router. This router cut the cross sections shown
below out of medium density fiberboard (MDF) used for the fabrication of the fairing plug.
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85
Appendix O: Vike Bike Dimensions
This appendix illustrates the major Vike Bike dimensions and angles for the chassis and fairing.
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86
Appendix P: Glossary of Human Powered Vehicle Terminology
The Bicycle industry has its own terminology for variety of components. Proper understanding of these
terms is critical to understanding the analysis and design in this report. Figure P1 illustrates the location
of Vike Bike components discussed in this report.
Figure P1: Vike Bike parts and locations
1. Rollbar 2. Rear Cassette 3. Chain Stay 4. Chain Ring 5. Chain Pulley 6. Main Tube 7. Seat Stay 8. Seat Tube 9. Seat Cross Tubes 10. Head Tube
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Appendix Q: Bill of Materials
Table Q1 HPV Overall Components Cost List Frame Parts List
Component Quantity Size Brand Color Model Source Retail Price Total Price Contact
Front Hub 1 32 hole Chris King Green Chris King $100.00 $0.00
Head Sets 1 1 1/8" Chris King Green Chris King $130.00 $0.00
Rear Hub 1 135 Chris King Green Chris King $150.00 $0.00
Chain 4 10 speed SRAM SRAM Chain PC-1050 10spd Revolver $22.25 $89.00 Jake Furniss
IRD Chain Link 10sp Shimano 3 10 speed Shimano IRD Chain Link 10sp Shimano Revolver $10.95 $32.85 Jake Furniss
SRAM Power Link 2000 9sp Gold 2 SRAM SRAM Power Link 2000 9sp Gold Revolver $4.95 $9.90 Jake Furniss
Inline Tube 700 x 18/20C PV / 60mm 4 Inline Inline Tube 700 x 18/20C PV / 60mm Revolver $4.95 $19.80 Jake Furniss
Cyclone Tube 20x1 1/8 PV 3 Cyclone Cyclone Tube 20x1 1/8 PV Revolver $4.95 $14.85 Jake Furniss
Maxxis Tire 700c X 23mm 2 Maxxis Tire 700c X 23mm Revolver $30.00 $60.00 Jake Furniss
Front Tire 2 451c Schwalbe Black Stelvio HS 350 Revolver $30.70 $61.40 Jake Furniss
Rear Tire 2 700c Schwalbe Black Stelvio HS 351 Revolver $28.44 $56.88 Jake Furniss
Front Rim 1 451c Velocity Black AeroHeat 451mm 32 Hole Black WO/MSW
Revolver $37.00 $37.00 Jake Furniss
Spokes 50 14G DT Silver Champion Revolver $2.00 $100.00 Jake Furniss
Nipples 50 14G DT Silver Champion Revolver $0.25 $12.50 Jake Furniss
SRAM Derailleur Force Rear 1 Sram SRAM Derailleur Force Rear Revolver $91.71 $91.71 Jake Furniss
Sugino double chainring bolt box of 5 1 Sugino Sugino double chainring bolt box of 5 Revolver $9.75 $9.75 Jake Furniss
Sugino Chainring Bolt Single Ring Set / 5 1 Sugino Sugino Chainring Bolt Single Ring Set / 5 Revolver $12.50 $12.50 Jake Furniss
Cranks 1 175mm SRAM Carbon SRAM Crankset Force GXP 175mm 39-53 WO/BB Revolver $231.15 $231.15 Jake Furniss
Shim Cleat SM-SH51 SPD Pair 7 Shimano Shim Cleat SM-SH51 SPD Pair Revolver $10.44 $73.08 Jake Furniss
Bottom Bracket 1 Sram Revolver $20.13 $20.13 Jake Furniss
Aheadset Starnut 1" 1 Aheadset Starnut 1" Revolver $2.95 $2.95 Jake Furniss
* REDLINE 18" Flight U6 Micro Mini Fork 1 1 Redline Black * REDLINE 18" Flight U6 Micro Mini Fork 1" Threadless Black
Revolver $35.34 $35.34 Jake Furniss
Cassette 1 SRAM OG-1070 10spd 11-26T Revolver $55.66 $55.66 Jake Furniss
Front Brake 1 6" Avid Avid Disc Brake BB7 Road Front 160mm Rotor Revolver $13.79 $13.79 Jake Furniss
SRAM Shift / Brake Lever Force Pair 1 Sram SRAM Shift / Brake Lever Force Pair Revolver $341.55 $341.55 Jake Furniss
Surly Brake Hanger Stainless 1 Surley Surly Brake Hanger Stainless Revolver $10.95 $10.95 Jake Furniss
Velox Rim Tape Cloth 17mm Single 2 Velox Velox Rim Tape Cloth 17mm Single Revolver $3.95 $7.90 Jake Furniss
Rear Rim 1 700c Velocity Black AeroHeat Revolver $37.00 $37.00 Jake Furniss
Jagwire Brake Cable Teflon Tandem 1.6mm X 2750mm ATB/RD 1 Jagwire Brake Cable Teflon Tandem 1.6mm X 2750mm ATB/RD $7.95 $7.95 Jake Furniss
JAG Tandem Der Cable Slick Gal 1.1 x 3000 1 JAG JAG Tandem Der Cable Slick Gal 1.1 x 3000 Revolver $3.95 $3.95 Jake Furniss
Rear Cantilever Brake 1 Avid Cantilever Brake Shorty Rear Revolver $24.15 $24.15 Jake Furniss
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Delta Axlerodz Bolt On Skewer 1 Delta Axlerodz Bolt On Skewer Revolver $17.95 $17.95 Jake Furniss
DT Champion 2.0 (14ga) 294mm single 64 1 Revolver $0.40 $0.40 Jake Furniss
Rear Wheel 1 650c Veloforma Black Veloforma $999.00 $0.00 Mark Duff
SRAM 10 speed TT shifter 1 Sram Carbon SRAM 10 speed TT shifter Veloforma $119.00 $119.00 Mark Duff
Cane Creek TT Bar end Brakes 1 Cane Creek
Black Cane Creek TT Bar end Brakes Veloforma $35.00 $0.00 Mark Duff
Idler Volae Over/Under... 1 64mm Terracycle Black Titanium 15% Discount Terracycle $133.45 $133.45 Robert Johnson
Idler Trice Dual Ti 2 Terracycle Titanium 15% Discount Terracycle $136.85 $273.70 Robert Johnson
Idler Mount 2" 2 Terracycle Universal Idler mount for 2" tube Terracycle $32.20 $64.40 Robert Johnson
GlideFlex Zero F 1 1" tube Terracycle Recumbent Steering mount for 1" tube Terracycle $92.65 $92.65 Robert Johnson
Handel Bar Mast 1 Terracycle Recumbent Bicycle Handlebar Mast Terracycle $75.65 $75.65 Robert Johnson
Handel Bars 1 Terracycle Handlebars Terracycle $29.75 $29.75 Robert Johnson
Fork 1 20" with D-Break Bachetta Coventry cycle Works $40.00 $0.00 Sherman
Chain Ring 2 75/65 Custom Premier Gear $0.00 $0.00 Ed Smith
6061 AL BB Relived Shell 1 41mm OD x 68mm wide Nova cycles $8.75 $8.75
AL7005 Road Dropout Adj 1 Al 7005 vertical Drop Nova cycles $19.15 $19.15
Easton head Tube AL 6061 1" 1 34.9 x 3.1 x 200mm Nova cycles $8.40 $8.40
6061 U-Brake Boss 1 6061 U-Brake Boss with center Miter Nova cycles $6.47 $6.47
Shipping cost 1 Nova cycles $40.00 $40.00
Total $2,363.41
Ironclad
Shirts and gloves $1,339.60 $669.80
Total $669.80
Tools
Angle Finder 4" 1 Tube Notching AC Winks $12.99 $12.99
1.5" 6 fluted end mill 1 Tube Notching McMaster Carr $71.87 $71.87
2" 8 fluted end mill 1 Tube Notching McMaster Carr $92.00 $92.00
Total $176.86
Hardware
Cap Screws 8 3" (3/8"-16) Clamps AC Winks $1.20 $9.60
All Thread 1 Bio-Mechanical Testing AC Winks $17.99 $17.99
Total $27.59
Raw Materials
6061 Aluminum Tubing 1 Vary Frame Materials Tube Service $170.00 $170.00
6061 Aluminum Tubing 1 Second Order Tube Service $188.00 $188.00
Aluminum Plate 1 2'x2'x0.75" Fixture Plate Alaskan Copper $238.48 $238.48
Total $596.48
Fairing Parts List
Tools
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Vacuum Bagging 1 FiberGlast $705.55 $705.55
Extra Vacuum Bagging 1 FiberGlast $94.50 $94.50
1/4 Drill Bit 1 Home depot $7.98 $7.98
Lite Weight 1 Baxter Auto Parts $19.99 $19.99
Lite Weight 1 Baxter Auto Parts $19.99 $19.99
Liquid Wax 1 Schucks Auto Supply $11.49 $11.49
Wet/Dry 400 1 Schucks Auto Supply $3.99 $3.99
Wet/Dry 800 1 Schucks Auto Supply $4.49 $4.49
Primer and Stuff (Kenneth) 1 Foster Auto Parts $35.53 $35.53
Canopy (Acrylic / Poly) 1 $150.00 $150.00
Total $1,053.51
Raw Materials
S2 Glass 5.60oz 70 yd TAP $14.00 $980.00
E Glass 1.5oz Mat 8 yd TAP $3.70 $29.60
5 Gal Structural Resin 1 Can TAP $210.00 $210.00
5 Gal Structural Resin 1 Can TAP $210.00 $210.00
Whitle Gel Coat 1 Gallon TAP $74.95 $74.95
White Pigment 8oz 3 Can TAP $15.25 $45.75
Green Pigment 8 oz 3 Can TAP $15.25 $45.75
PVA Mold Release 1 Gallon TAP $23.40 $23.40
Acetone 1 Gallon TAP $16.00 $16.00
CAB-O-SIL 1/8 LB 2 Can TAP $9.50 $19.00
Box Gloves 1 Box TAP $8.50 $8.50
2" Brushes 24 TAP $1.05 $25.20
Formula Five Can 1 Can TAP $11.25 $11.25
Gel Coat Gauge 1 TAP $8.00 $8.00
1 LB Clay 1 TAP $3.60 $3.60
10 oz MEKP 1 Can TAP $8.50 $8.50
BaltekMat 3 yd TAP $1.50 $4.50
Velcro 3 yd TAP $1.50 $4.50
1 qt Cups 6 TAP $0.65 $3.90
Tack Cloth 5 TAP $1.40 $7.00
Surfacing Resin 1 Gallon TAP $51.00 $51.00
E Glass 0.75oz Mat 10 yd TAP $1.90 $19.00
Micro Spheres 4oz 3 Can TAP $8.45 $25.35
Box Large Gloves 2 Box TAP $8.50 $17.00
5 qt Buckets 5 Each TAP $2.15 $10.75
1 qt Buckets 6 Each TAP $1.25 $7.50
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Latex Gloves 1 Each Walmart $4.32 $4.32
Duck Tape 1 Each Walmart $2.97 $2.97
Paint Brush 4 Each Walmart $0.88 $3.52
Syringe 1 Each TAP $3.10 $3.10
3/32" Balsa 12 Not Final Hobby Town USA $10.00 $120.00
1/4" Balsa 4 Not Final Hobby Town USA $5.00 $20.00
1/2" Balsa 6 Not Final Hobby Town USA $10.00 $60.00
Large Gloves 3 Box Rite Aid $7.99 $23.97
Medium gloves 3 Box Rite Aid $7.99 $23.97
Mask 1 Each Rite Aid $3.99 $3.99
MDF & (2x4) 1 Levi Home depot $185.00 $185.00 Total $2,320.84
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Table Q2 HPV Overall Components Cost List Frame
Components $2,363.41
Tools $176.86
Materials $596.48
Hardware $27.59
Frame Cost $3,164.34
Fairing
Tools $1,053.51
Materials $2,320.84
Fairing Cost $3,374.35
Competition
Rooms $2,061.46
Rental $850.00
Gas Wednesday Truck/Van $810.46
Gas Firday Car $33.00
Trailer $100.00
Registration $350.00
Food $924.00
Ironclad $669.80
Screen Printing $388.00
Travel Cost $6,186.72
Total Cost $12,725.41
Fund Raising
ASME Budget 2009 $1,720.66
ASME Budget 2008 $7,404.75
Senior ASME $1,000.00
Cummins NW $1,000.00
Cummins Foundation $1,000.00
Tap Plastics $500.00
Competition $100.00
Student Fee's
Total Raised $12,725.41
Balance $0.00
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Thank you to all of our sponsors.
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References
American Society of Mechanical Engineers. 2008. Interpretation of Rollover/side Protection Rules for 2008 HPVC Competitions. http://www.asme.org (1 March 2008).
American Society of Mechanical Engineers. 2008. Rules for the 2008 Human Powered Vehicle Challenge.
http://www.asme.org (15 March 2008). American Society for Testing and Materials. 1998. Annual Book of ASTM Standards. Designation D 790-
97 Standard Test Methods for Flexural Properties of Unreinforced and Reinforced Plastics and Electrical Insulating Materials: 145-152.
Callister, Jr. W.D. 2003. Materials science and engineering an introduction. 6th ed. New York: John Wiley
and Sons. Furniss, J., Kappa, B., Smith, M., Stenkamp, J., and N. Tavan. 2007. The Vike Trike II ASME West Coast
HPV Challenge. Portland, OR: PSU Mechanical Engineering Department. Guitterez, A. 2006. High-Strength Stainless Steels. Advanced Materials and Processes (June 2006). Landwer,G. E and D. Too. 2003. Factors affecting performance in human-powered vehicles: a
biomechanical model. Human Power 54:14-16. Reiser, P. 2001. Anaerobic Cycling Power Output With Variations in Recumbent Body
Configuration, Colorado State University Mechanical Engineering Dept. Tomai, G. 1999. The Leading Edge, Aerodynamic Design of Ultra-streamlined Land Vehicles. Cambridge,
MA: Robert Bentley. Too, D. 1990. The effect of body configuration on cycling performance. In E. Kreighbaum& McNeill
(eds.),Biomechanics in Sports VI (pp. 51-58). Montana State University,Bozeman, Montana ------. 1991. The effect of hip position/configuration on anaerobic power and capacity in cycling.
International Journal of Sports Biomechanics, 7(4), 359-370 ------. 1994. The effect of body orientation on power production in cycling. The Research Quarterly for
Exercise and Sport, 65, 308-315 ------. 1996. Comparison of joint angle and power production during upright and recumbent cycle
ergometry. In J.A. Hoffer, A. Chapman, J.J. Eng, A. Hodgson, T.E. Milner, & D. Sanderson (eds.) Proceedings of the Ninth Biennial Conference and Symposia of the Canadian Society for Biomechanics (pp. 184-185). Simon Fraser University, Burnaby, British Columbia, Canada.
Wilson, D.G. Bicycling Science. Third Edition. The MIT Press. Cambridge, Ma.
2004.