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
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
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APPENDIX E –SCHEDULE ...... E1 APPENDIX F -BUDGET ...... F1 APPENDIX G -CALCULATIONS ...... G1 APPENDIX H - DRAWING ...... H1
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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
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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
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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.
v LOW RACER RECUMBENT BIKE FRAME Eric Conner
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)
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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.
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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.
Rear Brakes Handlebars and Assembly
Crank and Frame Pedals Idlers
Cassette
Derailleur Fork Tubes
Figure 2: Recumbent Vocabulary (3)
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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
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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
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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
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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
Customer Customer importance
CUSTOM Relativeweight % Current Satisfaction
FEATURES Designer'sMultiplier Planned Satisfaction 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.
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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
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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.
.
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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
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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
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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.
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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.
12” 11” 15” 13” 51”
Figure 10: Load Distribution
W=131lb
Z = 119lb
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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.
R 131 M lb
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
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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.
o 12 lb 119 lb 119 lb 60
13”
14”
P2y
P1 P2x
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.
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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.
Maximum Stress Location
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.
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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
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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.
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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.
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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
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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.
11/2111/27 - 11/28-12/04 12/0512/11 - 12/1212/18 - 12/1912/25 - 12/261/01 - 1/02-1/08 1/091/15 - 1/16-1/22 1/231/29 - 1/30-2/05 2/062/12 - 2/13-2/19 2/202/26 - 2/27-3/05 3/063/12 - 3/13-3/19 3/203/26 - 3/27-4/02 4/034/09 - 4/10-4/16 4/174/23 - 4/24-4/30 5/015/07 - 5/08-5/14 5/15-5/21 5/225/28 - 5/296/04 - 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 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.
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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 Actual Cost 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 $300 $40 Material CNC Machining XXX $50
Bike Parts Double Chan $60 $60 Idler Idler Hardware $30 $30 Shift Cable $30 $30 Single Chain $40 $40 Idler Front Wheel Hub $50 $50 Rear Derailleur $50 $50 Chain $40 $40 Sprocket Kit $140 $140 Front Wheel $250 $185 Front Tire $50 $50
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Rear Axle Forks $45 XXX Handle Bar Kit $45 $45
Cassette $50 $50 Front Forks $225 $225 Brake Pads $55 $55 Brake System $70 $70 Front Brake System $70 $70 Rear Crank Set $130 $130 Rear Wheel $200 $200 Rear Tire $50 $50
Subtotal $2,905 $3,210
Miscellaneous $435 $350 (15%)
$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.
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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.
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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.
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APPENDIX A - RESEARCH
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 Great seat angle .com/Buyer%27s%20Guid Sleek design e/lowracers.htm 9/26/ Recumbent Tight steering Trike Perfect steering location Expensive Plain Chain drag
Appendix A1
http://patentpending.blogs.com/patent_phttp://patentpending.blogs.com/patent_pending_ending_ Seat is too upright for blog/bicycle_technology/page/2/ 9/26/10 maximum blood flow Early Recumbent Bike 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 thethe recumbent that set world speed records was by CharCharlesles Mochet. Other bikes in the Bicycle Technology Category.
Appendix A2
http://www.bentrideron Great seat angle line.com/Buyer%27s% 20Guide/lowracers.htm Sleek design 9/26/ Low Racer Tight steering Perfect steering location Expensive Hard to obtain Plain $4700 Chain drag Ridged Frame Carbon fiber dressed Lightweight Fast
http://www.bicycleman.co One person operation m/recumbents/catrike/catri ke-700.htm Efficient operation 9/26/ Catrike 700 Simple to operate Recumbent Tadpole Hard Cornering Tricycle Tough Steering East to learn Self-standing
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)
Appendix A3
http://patentpending.blogs. Poor Seat Angle com/patent_pending_blog/ Bad Steering Location 2005/02/the_first_recum.ht ml 9/26/05 First Cheap Materials Recumbent Bike 1902 Short Wheelbase Good Design Close/tight handling
An early recumbent bicycle, to J. Jarvis, 1902. Constructed of non-finished metal, which cause rustiness.
http://www.recumbents.com/wisil/stickbi Too high for a lower racer ke/default.htm 9/20/10 Rear Wheel Seat angle too high of degree Drive Recumbent bike. 20 pounds Steering is too high Front and rear wheel same size Control location is poor Solid piece framing Properly located idler for chain
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
Appendix A4
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? $1000 - $1500___ AVG $1500 - $2000___ LOW MODERATE MAXIMUM $2000 - $2500_2__ AVG: $2572 $2860 x > $3000 $2500 - $3000__2_ $3000 - ABOVE_3__ Thank you for your time. a
Appendix B1
APPENDIX C – QFD
Appendix C1
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 D1
APPENDIX E –SCHEDULE
Appendix E1
APPENDIX F -BUDGET
Appendix G1
APPENDIX G -CALCULATIONS
12lb 119lb 119lb
12” 11” 15” 13” ” Z 51” W
( )( ) (- )( ) ( )( ) ( )( )
( ( )
W=131lb
Z = 119lb
119lb 107lb
9” 11”” 15” 13”
-12lb
-131lb
1321in.lb
1141in.lb
144in.lb
9” 11” 15” 13” ” Appendix G1
R W
M
R= -131lb
( )
M=-786inlb
0 12lb 119lb 119lb 60 13lb
12” 11” 5” 13” 15” 14” ” P2x P2y P1
( )- ( ) ( )- ( )- ( )( ) ( )( )
( )
( )
Fy = 0=-12lb-73.55lb-119lb+P2-119lb-90sin (60)
401.5lb
Appendix G2
197lb
78lb
12” 11”” 10” 5” 13” 14”
-12lb
-85.55lb
-204.55lb
12” 11”” 10” 5” 13” 14”
-66lb
--536.5lb
-1597lb
-2582lb
Appendix G3
( )( )
( )
* 5(carbon fiber strength multiplier)
Appendix G4
APPENDIX H - DRAWING
Appendix H1
Appendix H2
Appendix H 3