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Low Racer Recumbent Bike Frame

A thesis submitted to the

Faculty of the Mechanical Engineering Technology Program

of the University of Cincinnati

in partial fulfillment of the

requirements for the degree of

Bachelor of Science

in Mechanical Engineering Technology

at the College of Engineering & Applied Science

by

ERIC CONNER

Bachelor of Science University of Cincinnati

May 2011

Faculty Advisor: Laura Caldwell

ACKNOWLEDGEMENTS

ii

TABLE OF CONTENTS

ACKNOWLEDGEMENTS ....................................................................................................... I

TABLE OF CONTENTS .......................................................................................................... II

LIST OF FIGURES ................................................................................................................ IV

LIST OF TABLES ................................................................................................................... V

ABSTRACT ............................................................................................................................. V

INTRODUCTION .................................................................................................................... 1

BACKGROUND ..................................................................................................................................................... 1 PROBLEM STATEMENT ........................................................................................................................................ 2 NOMENCLATURE ................................................................................................................................................ 3

COMMERCIALLY AVAILABLE OPTIONS ........................................................................ 4

FRONT WHEEL DRIVE FRAME............................................................................................................................... 4 LONG WHEELBASE FRAME .................................................................................................................................. 5 SHORT WHEELBASE FRAME ................................................................................................................................. 6

CUSTOMER FEEDBACK AND ANALYSIS ........................................................................ 7

SURVEY ANALYSIS .............................................................................................................................................. 7 PRODUCT FEATURES AND OBJECTIVES ................................................................................................................ 9

ALTERNATIVE DESIGNS AND SELECTION .................................................................. 10

THREE PIECE BOX FRAME .................................................................................................................................. 10 TWO PIECE BOX FRAME ..................................................................................................................................... 10 SINGLE PIECE TUBE FRAME ............................................................................................................................... 11

CALCULATIONS .................................................................................................................. 13

LOAD DISTRIBUTION ON PINS ............................................................................................................................ 13 CALCULATING FORCE AT FORK ANGLE ............................................................................................................. 14 CALCULATING FORCE ON SEAT BRACKET ......................................................................................................... 15 CALCULATING MAXIMUM STRESS ON FRAME .................................................................................................... 16

DRAWNING .......................................................................................................................... 17

FABRICATION ...................................................................................................................... 18

SCHEDULING AND BUDGET ............................................................................................ 21

ITEMIZATION .................................................................................................................................................... 21 BUDGET ............................................................................................................................................................ 22

CONCLUSSION..................................................................................................................... 24

BIBLIOGRAPHY ................................................................................................................... 25

APPENDIX A - RESEARCH ................................................................................................ A1

APPENDIX B - SURVEY ...................................................................................................... B1

APPENDIX C – QFD ............................................................................................................. C1

APPENDIX D – PRODUCT OBJECTIVE ........................................................................... D1

iii

APPENDIX E –SCHEDULE ................................................................................................. E1

APPENDIX F -BUDGET ....................................................................................................... F1

APPENDIX G -CALCULATIONS ....................................................................................... G1

APPENDIX H - DRAWING ................................................................................................. H1

iv

LIST OF FIGURES Figure 1: Recumbent Mid-Rise ................................................................................................. 1

Figure 2: Recumbent Vocabulary (3) ....................................................................................... 3 Figure 3: LowRacer FWD ........................................................................................................ 4 Figure 4: LowRacer LWB ........................................................................................................ 5 Figure 5: LowRacer SWB ......................................................................................................... 6 Figure 6: Three Piece Box Frame ........................................................................................... 10

Figure 7: Two Piece Box Frame ............................................................................................. 10 Figure 8: Single Piece Tube Frame ......................................................................................... 11 Figure 9: Riders Profile and Seat ............................................................................................ 13 Figure 10: Load Distribution .................................................................................................. 13

Figure 11: Front Fork Force .................................................................................................... 14 Figure 12: Loading on Seat ..................................................................................................... 15

Figure 13: Shear & Moment diagrams.................................................................................... 15 Figure 14: Maximum Stress Point .......................................................................................... 16

Figure 15: Solid Works Drawing ............................................................................................ 17 Figure 16: Frame Mold ........................................................................................................... 18 Figure 17: Stage 1 composite wrap ......................................................................................... 19

Figure 18: Stage 2 Kevlar wrap .............................................................................................. 19 Figure 19: Carbon fiber wrap .................................................................................................. 20

v

LIST OF TABLES Table 1: Results of Customer Requirements ............................................................................ 7

Table 2: Characteristic .............................................................................................................. 8 Table 3: Weight Objective Method ......................................................................................... 11 Table 4: Itemized Schedule ..................................................................................................... 21 Table 5: Itemized Budget ........................................................................................................ 22

v

ABSTRACT

An old age idea has been brought to the light over the last few decades. Recumbent are

now gaining popularity around the world with the introduction of clubs and races been hell

across the North America. With a heightened popularity, comes in increase in demand and

request specifications.

Recumbent bikes unlike the standard upright bikes many are familiar with, have a more

relaxed seating position similar to a recliner or slouching in a chair. The benefit of the

method of seating is that is increase the amount of blood flow throughout the body more

importantly the pelvic and legs of the rider, allowing for a greater distance with enjoyable

comfort.

Several varieties of recumbent bikes are in existence depending on the desire of the

enthusiast. The three class are; high risers, mid riser and low racers. Within these categories

there are three sub section; long wheel base, short wheel base with front wheel drive and

short wheel base with rear wheel drive. Each and every one of these unique creations is

custom designed for each individual rider.

The key components of sizing the rider for a recumbent bike are; weight - so that the

frame can with stand the total load in a dynamic condition, seated height - for properly

placing and length of the seat, inseam – to determine the distance the crank has to be and the

measurement for the knee to the ankle for the crank rotation.

The components of this project was design to decrease the amount of cost a high end

recumbent bike would usually cost, at the same time significantly reduce to weight. The

overall idea was to produce a top grade low racer recumbent framing system that would be

reasonably prices, available and lighter in weight after manufacturing.

LOW RACER RECUMBENT BIKE FRAME Eric Conner

1

INTRODUCTION

BACKGROUND

To distinguish between recumbent bicycles and the standard upright bicycles, look at the

seat position in figure 1. Recumbent bicycle are design for the rider to be in a reclined similar

to a lounge compared to the standard upright bicycle, for this reason the recumbent bike is

more ergonomic. The seat design allows for more distribution of the rider weight over a

larger area, and there is more support given to the lower lumbar, this allows for better blood

flow to the legs while riding. (1)

Figure 1: Recumbent Mid-Rise

Recumbent bicycles are also considered to be more aerodynamic compared to an

upright, since there is a considerably smaller profile when it comes to head wind. Recumbent

bicycles comes in many configurations: long wheel base, short wheel base, under and over

seat steering, front and rear wheel drives and much more. With a wide variety of categories

the recumbent design can be constructed, many possibilities are available to fit an

individual’s needs and preferences. (2)


2

PROBLEM STATEMENT

The current market for high performance recumbent bike is costly, which makes for a

difficult decision for many riders to choose cost over performance. With several models on

the market, each design has weight spectrums ranging from 19 pounds to 50 pounds. The

lighter frames, usually comes with a higher price tag due to material selection. The cost

ranges from $500 for a pure enjoyment of riding style bike to well over $10,000 for a lighter

high performance style. The propose solution is to build a recumbent bike frame that would

be comparable to a high performance frame in performance and weight for a fraction of the

cost.


3

NOMENCLATURE

In this report various terms will be used to describe the recumbent bicycle. These are the

common terms used by cyclist all around the world. Figure 2 shows these terms and their

respective location, which will aid in clarifying the report.

Figure 2: Recumbent Vocabulary (3)

Cassette

Derailleur

Rear Brakes Handlebars

and Assembly

Fork Tubes

Idlers

Crank and

Pedals Frame


4

COMMERCIALLY AVAILABLE OPTIONS

FRONT WHEEL DRIVE FRAME

Figure 3, a Front Wheel drive (FWD) recumbent model, is characterized by having the

entire drive train system connected to the front wheel. There are key components that must

be properly located to ensure a smooth operation for this system. First, proper placing of the

idlers, this ensures that there is no rubbing between the frame and the chain in order to

achieve the highest amount of efficiency and helps with the longevity of the components.

Secondly, the designer must ensure that the system moves in a complete unison; the crank,

pedals and idler must move along the same path as the wheel when engaged in turning or

maneuvering. The advantage of this structural design is the reduction in the amount of chain

utilized, which makes it easier to control its sagging and increase efficiency. (4)

Figure 3: LowRacer FWD


5

LONG WHEELBASE FRAME

Figure 4 shows a Long Wheelbase (LWB) recumbent model has a longer distance

between the front and rear wheel measuring over 60 inches or so. Usually the steering on

LWB HPV’s are located as an under seat operation, but with the lower racer design there is

minimum clearance. There is a familiar similarity between the LBW recumbent bicycle and

the standard upright bicycle; the pedals of both bicycles are located before the front wheel

and the drive mechanism is located at the rear. This design opposes a major disadvantage to

its counter parts, the excessively long chain can cause reduction in output, and the total

length reduces performance. (5) The LWB frame also has a major advantage; it is the most

familiar riding style to majority of cyclist making it easier to master even for novice cyclist.

Figure 4: LowRacer LWB


6

SHORT WHEELBASE FRAME

Figure 5 is the design of the most common of all the short wheelbase (SWB) recumbent

bikes are amongst the most desired of them all. As pictured in figure 5, the bikes name comes

from the total system having a smaller wheel in front then in the rear. With the pedals and

crank being located in front of the short wheel, the power transfer from the crank connection

to the chain then is transferred to the rear cassette to propel the bike.

Figure 5: LowRacer SWB

. This design is most sought after because of its ability to produce maximum power

output, therefore there is an increase in efficiency. The SWB recumbent bike wheel base

measures usually between 42 to 48 inches measure from the axels and commonly with a

20inch wheel in front and 26 inch wheel in the rear. SWB are the perfect design for sharp

turns and uphill tracking, therefore there frame designs are used for the fastest race bike;

combined with lightweight material SWB recumbent become sought after for racers all

around. (3) This design does have its drawbacks with the length of chain need for this bike.

The rider/designer must realize that the chain must be either routed to be out of the way of

the front wheel or that the chain will rub the front wheel during turns. (6) During interviews

from recumbent bike riders most if not all recommend and ride low racer with short wheel

base. See Appendix A for more research and interviews conducted


7

CUSTOMER FEEDBACK AND ANALYSIS

SURVEY ANALYSIS

In order to determine what the needs of the customers were for this product seven surveys

were constructed and distributed to bicycle enthusiast.

Table 1: Results of Customer Requirements

Custo

mer

imp

ort

ance

Desig

ner's M

ultip

lier

Curr

ent

Satisfa

ction

Pla

nn

ed S

atisfa

ctio

n

Rela

tive w

eig

ht %

Fit 5.00 1.10 3.57 4.00 14%

Weight 4.29 1.10 2.43 3.00 14%

Size 3.86 1.10 3.43 4.00 12%

Durability 3.86 1.10 3.43 4.00 12%

Efficiency 3.86 1.00 3.71 4.00 10%

Ease of Operation 3.71 1.00 4.14 4.20 9%

Handling 3.14 1.00 3.43 4.00 9%

Cost 2.86 1.10 3.57 4.00 8%

Safety 3.57 1.00 4.14 4.20 8%

Comfort 1.86 1.00 3.71 4.00 5%

The results in Table1, shows six different columns that will impact the design of the

recumbent bike frame. The first column shows a list of features that must be incorporated

into the design of the frame. These items were surveyed two ways; first was how important

are each one of the feature when if a new frame was being designed and how satisfied are

you with the current designs. The results from those sections of the survey generated

columns, “Customer Importance” and “Customer Satisfaction.” The numbers in these

columns are based off a “five point” scale with “one” being least importance or least satisfied

and “five” being very important or very satisfied. See appendix B for full survey and

calculations.

With the information obtained from the survey, the designer estimates a multiplier for

how much impact they will have on each specific feature during the design ranging from no

impact to ten percent. For this frame design table 1 shows that there are five critical arrears

the designer will impact; durability, fit, cost, size, and weight. After the designer multiplier is

given to each feature and the frame is designed, an assumption that a re-survey of the new

frame design will yield the column “Planned Satisfaction.” Planned satisfaction is higher

than the customer satisfaction due to the fact that the design wants to be better than current

market and outperform the requirements.

CUSTOM

FEATURES


8

The last column in table 1 is relative weight percent. Relative weight percent is

calculated all the columns if table 1. See Appendix C for detail calculations and equations.

This percentage tells the designer how important each feature is when the new frame is

designed. With this information the designer knows were the main focus and most time

should be spent to meet the customer requirements.

The engineering characteristics can be found in Appendix C. These characteristics are

identified by the designer and are considered to be the key items for designing and

manufacturing the frame. Each characteristic is view across all the product objectives then

the column is added together, this number is included in the relative weight. The things that

impacted the most was the ideas that would meet the requirements of the customers, seen in

Table 2

Table 2: Characteristic


9

PRODUCT FEATURES AND OBJECTIVES

The product features and objectives are the same items from the survey (See Appendix B

for survey). Each of the customer features are ranked by percent of importance, from there,

values are assigned from the engineer as an added multiplier. The engineering characteristics

describe how the designer is going to meet each feature through measurable criteria. The

other remaining product features and objective are: efficiency, handling, safety, cost and

comfort. See Appendix D for a complete list of feature and relative engineering

characteristics. The five most important product features are:

Fit: 14%

1. Each bike is specifically designed for each individual operator at time of purchase regardless of

gender. Nonadjustable.

2. Human factors

- Measure of the rider’s inseam to determine the distance at which the crank will be located

from the rider while seated.

- The distance from rides knee to their ankle to determine the height the crank should be in

relation to the riders crank stroke.

Weight: 14%

1. 25 to 35 pound range

Size: 12%

1.) Will not exceed 80 inches in length

2.) The back rest will not exceed 12inch in width

Durability: 12%

1. Quality materials selected based upon material properties for usage

Use design factor of safety

Efficiency: 10%

1.) Minimize the friction between the chain and frame, by incorporating idlers to guide the chain

links away from other surfaces.

2.) Crank placement determined by power and torque from the seat position

Eases of Operation: 9%

1. The bike is manufactured so that the only operator is the person riding it. There will be no need

for another person’s assistance through the entire operation of riding the bike.

.


10

ALTERNATIVE DESIGNS AND SELECTION

Below are three alternative design models: Three Piece Box frame, Two Piece Box

Frame and Single Piece Tubular Frame. Each one of these sketches has identifying locations

of the main hardware (crank, front, forks, and rear axle).

THREE PIECE BOX FRAME The first concept sketch shown in figure 6 consists of three separate components, the

main frame, and rear fork and seat bracket. This ridge frame design offers a strong support

for the rider, but has two flaws. Since this design is constructed in three separate pieces,

attaching if all the parts need to happen, rather with the use of common material, rivets or

bolts. The two flaws are at the two connection joints, they oppose a problem because

connection points are under extreme stress. Remember this frame will be under compression

and tension from the rider and dynamic loading.

Figure 6: Three Piece Box Frame

TWO PIECE BOX FRAME The second concept sketch shown in figure 7 is very similar to the Three Piece Box

design, but only has two pieces not three. This design would be stronger than the Three Piece

design due to the fact that once the pices are connect together, there is only one joint that

would have stress localized.

Figure 7: Two Piece Box Frame


11

SINGLE PIECE TUBE FRAME

The third concept sketch shown in figure 8 is the one that is selected for design. This

design is considered to be the strong since it is constructed using one full piece of material

without seems. This design also is the easiest to produce and in the least amount of time and

handling., which insures structural integrity.

Figure 8: Single Piece Tube Frame

These three concepts were evaluated using a weighted decision matrix using a five-point

scale. The scores range from zero being inadequate to four being excellent. Only the design

criteria that were different between the two concepts were scored using relative weights

taken from the QFD See Appendix C. Table 3 shows the design criteria and the rating

designated to each design by the engineering. The highlighted items are the critical

differences. The Single Piece Tube design score the highest, therefor it will be the design use

and produced.

Table 3: Weight Objective Method

DESIGN WEIGHT TWO PIECE BOX FRAME THREE PIECE BOX FRAME ONE PIECE TUBULAR FRAME

CRITERIA FACTOR SCORE RATING SCORE RATING SCORE RATING

Fit 0.17 4 0.68 4 0.68 4 0.68

Weight 0.13 3 0.39 2 0.26 4 0.52

Size 0.11 4 0.44 4 0.44 4 0.44

Durability 0.11 3 0.33 2 0.22 4 0.44

Ease of Operation 0.1 3 0.3 3 0.3 3 0.3

Efficiency 0.09 4 0.36 4 0.36 4 0.36

Handling 0.08 4 0.32 4 0.32 4 0.32

Safety 0.08 3 0.24 3 0.24 4 0.32

Cost 0.08 3 0.24 3 0.24 4 0.32

Comfort 0.04 4 0.16 4 0.16 4 0.16

1 3.46 3.22 3.86


12

Although a lot of the design criterion were rated the same, the important differences are

safety, durability, cost and weight. Safety was impacted by the sharp edged that exist in the

box style design, so the design with smooth rounded parts were rated higher. Durability was

impacted by the ability for the bike to stand the riders weight and the dynamic loading

condition, so giving the idea that joint and bond location propose weakness in structure

therefore the single modeled piece was rated higher. Cost and weight was impacted by extra

material that would be needed to combine the piece from the “Three” and “Two” piece

designs, so the Single piece design was rated higher.


13

CALCULATIONS

LOAD DISTRIBUTION ON PINS

Figure 9 is the profile of the rider in position on the seat. The ride has a total weight of

190 pounds which is loaded on the two brackets of the seat that has a overall rating of 250

pound limit. Instead of including a factor of safety the design calculation will use the

distribution of the 250 pound limit for the seat. The head of the rider is said to weigh 12

pounds, the remaining of the 238pouns is distributed 50/50 for the torso and legs.

Figure 9: Riders Profile and Seat

The load for figure 10 must be found across the two main supports of the entire system,

which is the front and rear wheel. The free bodies diagram in figure 10 shows the force

acting on the system. The two unknowns Z(rear wheel) and W (front wheel) must be found

using the distance and weight distribution of the rider. The loads are W=131lb and Z=119lb.

See appendix G for full calculations.

Figure 10: Load Distribution

W=131lb

Z = 119lb

51”

12” 13” 15” 11”


14

CALCULATING FORCE AT FORK ANGLE

Due to the rake angle of the front fork, a new position “R” is required to be calculated.

Figure 11 shows the front wheel with W already defined from the previous calculation, bow

R and M must be found for the fork location.

Figure 11: Front Fork Force

The calculations below show the force load and loading condition for the front fork with

the applied loads. As displayed “R” the fork location has a negative (downward) orientation,

which is opposite of “W” the normal force from eh wheel axle. There is also an “M” moment

at the same location show in positive position but is a negative moment. See appendix G for

full calculations.

R= -131lb

( )

M=-786inlb

131

lb

R

M


15

CALCULATING FORCE ON SEAT BRACKET

Point P1, P2x and P2y are the only points for which the load is applied. Figure 8 show

the free body diagram that represents the rider’s weight distribution, force from the pedals,

and distance. Appendix G can be viewed for further detail regarding the calculations, free

body diagrams, shear and moment diagrams. There is an addition 60degree force added,

cause by the angle at which the pedal are engaged.P1 is -401.5 lb, P2x is 45 lb and P2y is -

73.55 lb. For full calculation details see Appendix G.

Figure 12: Loading on Seat

Figure 13 is the shear and moment diagrams that represent the combination of the load with their point distances, to achieve the maximum load.

Figure 13: Shear & Moment diagrams

The shear and moment diagrams in figure 13 will be used to identify the point location

on the frame that has the maximum bend moment. These values are used in the next section

along with moment of inertia and radii of the tube for calculating maximum psi.

14”

12 lb 119 lb

119 lb

P1 P2x

P2y

13”

60o


16

CALCULATING MAXIMUM STRESS ON FRAME

The location can be found in figure 14. The maximum stress occurs at point P2y from

the calculation; this is the stress due to the bending moment. The equation Mc/I was used to

in calculation were the cross sect of 2inch hollow diameter with a 0.110 inch thickness. See

Appendix G for detailed calculation.

Figure 14: Maximum Stress Point

( )( )

( )

* 5(carbon fiber strength multiplier)

The Factor of Safety is calculating using the yield strength of Aluminum 6061-T6 this is

because, Aluminum is a homogeneous mixture and the building material used for the frame

(carbon fiber and Kevlar) in not. But one thing that is known is that Carbon fiber yield

strength is five time great that of Aluminum 6061-T6. According MIT (Massachusetts

Institute of Technology) allowable factory of safety for dynamic systems is 4 of greater.

Maximum Stress Location


17

DRAWNING

Figure 15 is the shop drawing of the frame system. It also includes the front and rear

wheels to show the correct profile of the frame. Also included are the front forks and crank

which all these parts were purchase commercially. As for the seat used, it was also

commercially purchased it can be seen in Appendix I (other photos). Refer to Appendix H for

product drawings, which outline the specification of the frame design, dimensions, overall

geometry and build of materials.

Figure 15: Solid Works Drawing


18

FABRICATION

The fabrication process was down in several steps to ensure that the epoxy has ample

time to cure to its final state. First the mold was created using the solid works model

converted into CNC langue. Figure 16 is the final 3D life size model of the frame.

Figure 16: Frame Mold

The Styrofoam mold is the back bone of the composite material. It allows for easy

application and guidance for laying the first few layers to harden. The image depicts two

separate piece because for two reasons; the first being the soldworks model has the main

frame section in the side plan while the rear attachment is on the top plan. Then the total

finish frame was too big for the CNC machine to handle in one piece. Appendix H gives a

more in-depth idea of the different plans.


19

Figure 17 is the first stage of composite wrap. The Styrofoam was wrap using fiberglass,

Kevlar and a curing epoxy to harden the composite material. The Kevlar was added in the

first stage to reinforce the point carrying the greatest load.

Figure 17: Stage 1 composite wrap

Once the first stage is cured roughly 7 to 10 days depending on air temperature, the

Styrofoam core was extracted to achieve a light weight frame. Stage 2 can be seen in figure

18, it has a Kevlar composite wrap with an extra reinforcement.

Figure 18: Stage 2 Kevlar wrap

Same as Stage 1, the stage also has to be cured completely taking 7 to 10 days

temperature and humidity dependent. This stage will begin providing the strength needed to

support the rider and the entire dynamic loading. Kevlar has the greatest strength in the

tensile portion or the “bottom half” of the cross-section if the frame was split on the top plan.


20

The final stage, Stage 3 is the carbon fiber warp. It is composed of 4 layers of 3k (by weight)

2x2 twilled material. This material has the same amount of strength in both MD and CD

direction, reducing weak spots. Figure 19 show the fully completed frame in its proper

profile.

Figure 19: Carbon fiber wrap


21

SCHEDULING AND BUDGET

ITEMIZATION Table 4 below is a project schedules so that everything such as design, purchase,

fabrication, assembly, and testing can be seen when they are needed to be taken place.

January 30 thru February 12 is considered to be a design freeze. During this time there will

not be any major changes to the frame design. This built in design freeze helps keeps the

designer on target for getting the project done on time. This is done by forcing the designer to

keep the latest 3D model and move on to the next forecasted task, fabrications. March 20 thru

March 26, is a break were there will be no meetings with respective advisors. During this

time a few things should be happening; most if not all the part should be at the designers

disposal, fabricating the frame should nearly be finished, and the assembly should be taking

place. See Appendix E to view the full itemized schedule.

Table 4: Itemized Schedule

Table 4 has two dates for each task; the date in line with the task was the original

prediction. As for the actual date the task was achieved, the date below the predicted task.

11

/21

- 1

1/2

7

11

/28

- 1

2/0

4

12

/05

- 1

2/1

1

12

/12

- 1

2/1

8

12

/19

- 1

2/2

5

12

/26

- 1

/01

1/0

2-1

/08

1/0

9 -

1/1

5

1/1

6-1

/22

1/2

3 -

1/2

9

1/3

0-2

/05

2/0

6 -

2/1

2

2/1

3-2

/19

2/2

0 -

2/2

6

2/2

7-3

/05

3/0

6 -

3/1

2

3/1

3-3

/19

3/2

0 -

3/2

6

3/2

7-4

/02

4/0

3 -

4/0

9

4/1

0-4

/16

4/1

7 -

4/2

3

4/2

4-4

/30

5/0

1 -

5/0

7

5/0

8-5

/14

5/1

5-5

/21

5/2

2 -

5/2

8

5/2

9 -

6/0

4

TASK

Proof of design contract 8

8

Concepts sketches 8

8

3D software model design 5

5

Design Calculations 26

26

Part ordering 23

26

Real size 2D print 2

26

3D mold 16

16

Lay Carbon materials Part 1 2

2

Design Freeze 9

9

Lay Carbon materials Part 2 16

16

Lay Carbon material Part 3 30

30

Oral 1 1

1

Report 1 15

15

Assembly and test 27

16

Demo (advisor) 11

20

Demo (ALL) 18

20

Oral 2 25

24

Final report 5

8


22

After the design, fabrication, and part ordering is complete, next comes the assembly of

the components and testing. These seven weeks are critical; a perfect fit of all fabricated part

must fit the parts purchase. The seven week timeline allows for error in part ordering,

therefore reordering of a specific item can be achieved in time to assembly and test. Another

one week buffer is built into the schedule between testing and demonstration the finished

product, so that proper functions are displayed properly.

BUDGET

For this project the purchasing of part is spread out over fifteen weeks, starting during

the holiday break and going thru to March 20. Part ordering is critical when trying to design

some new and improved on a set budget; with this several part companies and be contacted in

order to find the best deals for top quality parts. Table 5 is a forecasted cost for all materials

and may change depending on the generosity of companies when ordering there parts for his

project. See Appendix F for a list of item to be purchased for the frame project.

Table 5: Itemized Budget

Frame Parts Forecast

Cost

Actual

Cost

Fabric Composite $400 $1,000

Resin $175 $350

Vacuum Pump $150 xxx

Material Kit $75 $75

Pump Line $25 $25

Fiber Glass $100 $100

Foam Core

Material

$300 $40

CNC Machining XXX $50

Bike Parts

Double Chan

Idler

$60 $60

Idler Hardware $30 $30

Shift Cable $30 $30

Single Chain

Idler

$40 $40

Front Wheel Hub $50 $50

Rear Derailleur $50 $50

Chain $40 $40

Sprocket Kit $140 $140

Front Wheel $250 $185

Front Tire $50 $50


23

Rear Axle Forks $45 XXX

Handle Bar Kit $45 $45

Cassette $50 $50

Front Forks $225 $225

Brake Pads $55 $55

Brake System

Front

$70 $70

Brake System

Rear

$70 $70

Crank Set $130 $130

Rear Wheel $200 $200

Rear Tire $50 $50

Subtotal $2,905 $3,210

Miscellaneous

(15%)

$435 $350

$3,340 $3,560

Table for above has 3 different columns; Items, forecasted cost and actual cost. Due to

unforeseen mishaps such as temperature and time, I went over budget by $220from buying

extra materials i did not budget for and not pricing accordingly.


24

CONCLUSSION

With the growth of recumbent enthusiast globally, a wider range of improvement and

satisfaction in manufacturing must also grow. With the creation of a new generation of

recumbent bikes suitable for everyone’s style, shape and requirements, cost is plays the key

turning point for which selection is determined. This final product was design of a specific

individual, but can be altered in the manufacturing phase to deliver customer needs and

requirements for a significantly reduce cost. By making high performance recumbent bikes

affordable, the numbers will soon rise opening the doors for greater opportunity.


25

BIBLIOGRAPHY 1. The First Recumbent Bike? Patent Pending Blog - Patents and the History of Technology.

[Online] February 17, 2005. [Cited: September 26, 2010.]

http://www.patentpending.blogs.com/patent_pending_blog/2005/02/the_first_recumbent.htm

l.

2. Linear Limo LWB Recumbent Bike. Linear. [Online] 2003. [Cited: Septemeber 26, 2010.]

http://www.linearrecumbent.com/.

3. Recumbent LWB. [Online] [Cited: October 22, 2011.] http://www.recumbent-bikes-truth-

for-you.com/long-wheelbase.html.

4. SlowWheel Cycling - Patents and the History of Technology. [Online] May 28, 2006.

[Cited: September 26, 2010.]

http://www.patentpending.blogs.com/patent_pending_blog/bicycle_technology/page/2/.

5. Short Wheelbase Recumbents Are Just Like The Sports Car Of Recumbent Bikes. [Online]

[Cited: September 26, 2010.] http://www.recumbent-bikes-truth-for-you.com/short-

wheelbase.html.

6. Recumbent Bicycle. Recumbent Glossary of Terms and Definitions. [Online] [Cited:

Novemebr 14, 2010.] http://www.rbr.info/support/recumbent-glossary.html.

7. check your pulse when your low racer loose! recumbent-bike-thruth-for-you. [Online]

[Cited: September 26, 2010.] http://www.recumbent-bikes-truth-for-you.com/low-racer.html.

8. Catrike 700 Recumbent Trike. Bicycle Man. [Online] 1998. [Cited: September 26, 2010.]

http://www.bicycleman.com/recumbents/catrike/catrike-700.htm.

Appendix A1

APPENDIX A - RESEARCH

Great seat angle

Sleek design

Tight steering

Perfect steering location

Expensive

Plain

Chain drag

Interview with customer, September 23, 2010

Miguel Jensen Didulo, Recumbent Bike Builder, London, Ontario Canada

Safety

Cheap to build

“X-Seam” perfection

Short wheelbase design

Precision of steering

Aerodynamics at under front bracket

Affordable to purchase

Interview with customer, September 23, 2010

Mike Mowett, Recumbent Bike Racer, Saint Clair Shores, MI

Ability to keep body tight

More effective seat angle

Steering effectiveness

Rear driven equal more power

Chest steering location

Short Wheel base design

Chain loop routing

Safe

Affordable to purchase

http://www.bentrideronline.com/Buyer%27s%20Guid

e/lowracers.htm

9/26/ Recumbent

Trike

http://www.bentrideronline.com/Buyer%27s%20Guide/lowracers.htm



Appendix A2

Here is an early (1949) recumbent bike which is similar to

many recumbent bikes seen on the road today. An even

earlier recumbent was by Jarvis, and the recumbent that set

world speed records was by Charles Mochet. Other bikes

in the Bicycle Technology Category.

Seat is too upright for

maximum blood flow

Steering column is

extremely high

Not Aerodynamic

Short Wheelbase design

Maximum power for

outpuy

Here is an early (1949) recumbent bike which is similar to

many recumbent bikes seen on the road today. An even

earlier recumbent was by Jarvis, and the recumbent that set

world speed records was by Charles Mochet. Other bikes

in the Bicycle Technology Category.

Seat is too upright for

maximum blood flow

Steering column is

extremely high

Not Aerodynamic

Short Wheelbase design

Maximum power for

outpuy

http://patentpending.blogs.com/patent_pending_

blog/bicycle_technology/page/2/ 9/26/10

Early Recumbent Bike

http://patentpending.blogs.com/patent_pending_

blog/bicycle_technology/page/2/ 9/26/10

Early Recumbent Bike

http://patentpending.blogs.com/patent_pending_blog/2005/02/the_first_recum.html

http://patentpending.blogs.com/patent_pending_blog/2005/03/fastest_bike_in.html

http://patentpending.blogs.com/patent_pending_blog/bicycle_technology/index.html


http://patentpending.blogs.com/patent_pending_blog/2005/03/fastest_bike_in.html

http://patentpending.blogs.com/patent_pending_blog/bicycle_technology/index.html

http://patentpending.blogs.com/patent_pending_blog/bicycle_technology/page/2/




Appendix A3

Hard to obtain

$4700

Ridged Frame

Carbon fiber dressed

Lightweight

Fast

Great seat angle

Sleek design

Tight steering

Perfect steering location

Expensive

Plain

Chain drag

Wheels Front 16 " (349) • Wheel Rear 700c • Weight 33 Pounds (15.0 Kg) • Wheel Base 45" (1143mm) • Wheel Track 27.5” (699mm) • Total Width 31.5" (800mm) • Seat Height 7.00 " (178mm) • Turning Circle 18' 4 " (5.59m) • Turning Radius 110" (2.78m) • Gear Inch Range 25” to 130” • Ground Clearance 2.25” (57mm)

One person operation

Efficient operation

Simple to operate

Hard Cornering

Tough Steering

East to learn

Self-standing

http://www.bentrideronline.com/Buyer%27s%

20Guide/lowracers.htm

9/26/ Low Racer

http://www.bicycleman.com/recumbents/catrike/catri

ke-700.htm

9/26/ Catrike 700

Recumbent Tadpole Tricycle




http://www.bicycleman.com/recumbents/catrike/catrike-700.htm



Appendix A4

Rides nicely.

Trail seems right.

Cockpit position feels right and is comfy.

Crakes & shifting work well

Seat and frame seem solid when cranking on it.

20 pounds

Too high for a lower racer

Seat angle too high of degree

Steering is too high

Front and rear wheel same size

Control location is poor

Solid piece framing

Properly located idler for chain

An early recumbent bicycle, to J. Jarvis,

1902. Constructed of non-finished metal, which

cause rustiness.

Poor Seat Angle

Bad Steering Location

Cheap Materials

Short Wheelbase

Good Design

Close/tight handling

http://patentpending.blogs.

com/patent_pending_blog/

2005/02/the_first_recum.html 9/26/05 First

Recumbent Bike 1902

http://www.recumbents.com/wisil/stickbi

ke/default.htm 9/20/10 Rear Wheel

Drive Recumbent bike. 20 pounds





http://www.recumbents.com/wisil/stickbike/default.htm

http://www.recumbents.com/wisil/stickbike/default.htm

Appendix B1

APPENDIX B - SURVEY

Recumbent Bike Redesign

CUSTOMER SURVEY

The purpose of this survey is to recognize and understand what factors are weighed when designing

a recumbent bike, also to acknowledge the efficiency of the current production models.

How important is each feature to you for the design of a new recumbent bike?

Please circle the appropriate answer. 1 = low importance 5 = high importance AVG Safety 1 2- (1) 3-(2) 4-(3) 5-(1) N/A 3.85

Durability 1 2 3-(3) 4-(2) 5-(2) N/A 3.86

Fit 1 2 3 4 5-(7) N/A 5.00

Cost 1-(1) 2-(1) 3-(3) 4-(2) 5 N/A 2.86

Comfort 1-(1) 2 3-(4) 4 5 N/A 1.86

Ease of operation 1-(1) 2 3-(1) 4-(3) 5-(2) N/A 3.71

Handling 1-(1) 2-(1) 3-(2) 4-(2) 5(1) N/A 3.14

Size 1 2 3-(3) 4-(2) 5-(2) N/A 3.86

Weight 1-(1) 2 3 4-(1) 5-(5) N/A 4.29

Efficiency 1 2-(1) 3-(1) 4-(3) 5-(2) N/A 3.86

How satisfied are you with the current market recumbent bikes?

Please circle the appropriate answer. 1 = very UNsatisfied 5 = very satisfied AVG

Safety 1 2 3 4-(6) 5-(1) N/A 4.14

Durability 1-(1) 2 3-(1) 4-(5) 5 N/A 3.43

Fit 1 2 3-(4) 4-(2) 5-(1) N/A 3.57

Cost 1-(1) 2-(1) 3 4-(3) 5-(2) N/A 3.57

Comfort 1 2 3-(3) 4-(3) 5-(1) N/A 3.71

Ease of operation 1 2 3-(1) 4-(4) 5-(2) N/A 4.14

Handling 1 2-(2) 3-(1) 4-(3) 5-(1) N/A 3.43

Size 1 2 3-(4) 4-(3) 5 N/A 3.43

Weight 1-(1) 2-(3) 3-(2) 4-(1) 5 N/A 2.43

Efficiency 1 2 3-(4) 4-(1) 5-(2) N/A 3.71

How much are you will to pay for a recumbent bike that meets all of your needs? AVG

Thank you for your time. a

$1000 - $1500___

$1500 - $2000___

$2000 - $2500_2__

$2500 - $3000__2_

$3000 - ABOVE_3__

LOW MODERATE MAXIMUM

AVG: $2572 $2860 x > $3000

Appendix C1

APPENDIX C – QFD

Appendix D1

APPENDIX D – PRODUCT OBJECTIVE Product Objectives

Recumbent Low Racer Fame

The following is a list of product objectives and how they will be obtained or measured

to ensure that the goal of the project was met. The product objectives will focus on the

structural design of the recumbent bike low racer. The bike style is suitable for low traffic

area.

Fit: 14%

2. Each bike is specifically designed for each individual operator at time of purchase regardless of

gender. Nonadjustable.

3. Human factors

- Measure of the rider’s inseam to determine the distance at which the crank will be located

from the rider while seated.

- The distance from rides knee to their ankle to determine the height the crank should be in

relation to the riders crank stroke.

Weight: 14%

2. 25 to 35 pound range

Size: 12%

3.) Will not exceed 80 inches in length

4.) The back rest will not exceed 12inch in width

Durability: 12%

4. Quality materials selected based upon material properties for usage

Use design factor of safety

Efficiency: 10%

3.) Minimize the friction between the chain and frame, by incorporating idlers to guide the chain

links away from other surfaces.

4.) Crank placement determined by power and torque from the seat position

Eases of Operation: 9%

2. The bike is manufactured so that the only operator is the person riding it. There will be no need

for another person’s assistance through the entire operation of riding the bike.

Handling: 9%

1. The bike will have smooth steering, by using bearings and the minimum amount of

clearance between the fork tube and hub. This will reduce rubbing, grinding, and

friction when turning the steering.

Safety: 8% 1. No sharp edges to cause injuries

5. Attached mirrors

6. Manual braking system

7. Ability to place feet down and up without interruptions

Cost: 8%

8. The manufacturing of the entire system cost will range from $2500-$3200.

Comfort: 5%

The seat will be designed to conform specially for the rider contour/body shape and torso length.

Appendix E1

APPENDIX E –SCHEDULE

Appendix G1

APPENDIX F -BUDGET

Appendix G1

APPENDIX G -CALCULATIONS

( )( ) (- )( ) ( )( ) ( )( )

( ( )

W=131lb

Z = 119lb

Z

12lb 119lb 119lb

W

12” 11”

” 15” 13”

51”

9” 11”” 15” 13”

9” 11”

” 15” 13”

119lb

107lb

-131lb

-12lb

144in.lb

1321in.lb

1141in.lb

Appendix G2

R= -131lb

( )

M=-786inlb

( )- ( ) ( )- ( )- ( )( ) ( )( )

( )

( )

Fy = 0=-12lb-73.55lb-119lb+P2-119lb-90sin (60)

401.5lb

W R

M

12” 11”

” 15” 13”

12lb 119lb 119lb

P1 P2y

P2x

14”

600

13lb

5”

Appendix G3

12” 11”” 10” 5” 13” 14”

12” 11”” 10” 5” 13” 14”

-12lb

-85.55lb

-204.55lb

78lb

197lb

-66lb

--536.5lb

-2582lb

-1597lb

Appendix G4

( )( )

( )

* 5(carbon fiber strength multiplier)

Appendix H1

APPENDIX H - DRAWING

Appendix H2

Appendix H3

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