2. Design and construct, respective of constraints, a single-rider recumbent fully faired human powered vehicle. Compete and win the 2010 ASME East Human Powered Vehicle Challenge. Objective
3. Matthew Wright Team Manager/Seating Position/Steering James VanBiervliet Frame Dante Mucaro Drivetrain/Frame Integrations Rich Nelson Fairing Advisor: Dr. Lisa Grega Co-Advisors: Dr. Norman Asper Dr. Manish Paliwal Team Members
4. 2010 ASME East Human Powered Vehicle Challenge “to provide an opportunity for engineering students to demonstrate application of sound engineering design principles toward the development of efficient, sustainable, and practical human-powered vehicles” May 7-9, 2010 Central Connecticut State University
5. 2010 ASME East Human Powered Vehicle Challenge Design Event Submission of design report and presentation Drag Event Double elimination tournament .6-.8 km track Endurance Event 2 ½ hours Multiple Drivers
6. Design ConstraintsGoals Roll Bar Loading Top: 600 lb Side: 300 lb Turning Radius: 25 ft Braking Distance (15 mph-0 mph): 20 ft Incorporate Shoulder Harness Top Speed in Drag Competition: 50 mph Endurance Average Speed: 30 mph
8. Ensure that the project team completes the task at hand Develop the plan with the team and manages the team’s performance of tasks Make sure the project is delivered in budget, on schedule, and is practical Project Management
9. Google Calendar Coordinate schedules for meetings Inform team members of project deadlines Project Management
10. Dropbox Online file storage service All team members and advisors Project website tcnjhumanpowered.blogspot.com Enable public to be informed and track progress of the project Project Management
17. Above seat steering system chosen Head tube too far away from rider for standard straight bicycle handlebars Solid bent handlebars (Tiller steering) Universal Joint with steering column to handlebars Enables easy entrance and exit of vehicle Steering System
20. Withstand a 600 lb top load at a 12 degree angle towards rear of vehicle Support 300 lb loading directly to the side of the vehicle All team members must fit inside Frame - Constraints http://www.wind-water.nl/rec_build_n.html
21. Original designs included one under seat support and two converging supports on the side of the seat Pedals were located behind the front wheel Frame - Design http://bikemart.com
23. Second frame design incorporated a tub like style Provides anchor points for fairing Used a pedal set above the front wheel to reduce overall length length Frame - Design
25. Ultimately chose the second design Kept length to a minimum Provided better support for the fairing Gave driver the most leg room Frame - Design
26. Needs to be strong and durable Since the goal is speed, lightweight materials are essential Wanted a material that would minimize cost without sacrificing safety Frame - Material Selection
27. Two materials were considered 4130 Normalized Steel (Chromolly) Bamboo Poles 4130 Steel was found to be used for frame construction by retailers Bamboo was found to be used by independent manufacturers Frame – Material Selection www.bmeres.com
28. 4130 Steel properties are widely available but little can be found about Bamboo’s properties so tests were done to verify. Frame – Material Selection
29. Frame – Material Selection http://bambus.rwth-aachen.de/ http://www.tropicaltikis.com/
34. Drivetrain Requirements High range of gears for acceleration runs and endurance testing Durable Easily serviced Utilize standard bicycle drivetrain components for cost 2 wheel layout Minimize weight
35. Wheel Choices 2 wheeled vehicle Front or rear drive wheel: Image Sourced: http://www.rose-hulman.edu/hpv/ Image Sourced: http://img.alibaba.com/photo/10798856/Recumbent_Bike.jpg
36. Wheel selection Rear drive wheel system selected Wheel selection: Maximize acceleration and overall speed 20” front wheel Compact Lightweight 26” drive wheel Maximize development Adaptable hubs
37. Drivetrain System Selection Requirements: Wide gear range Durable Inexpensive Adaptable Easily serviced Three options Chain drive Shaft drive Belt drive
40. Option 3: Belt Drive Single front gear Single rear gear Toothed belt replaces chain Gearing through hub Image Source: http://paketabike.files.wordpress.com/2009/08/wac_corp_beltdrive2.jpg
41. Decision: Chain Drive Gearing: Top speed and acceleration Many available gears High speed: High front-to-rear ratio Quick start: Low front-to-rear ratio Acceleration: Proper gear ratio spacing
42. Sprocket options Standard road bike drivetrain Ten speed cassette Two speed crankset Modify to achieve proper gear spacing while getting a higher top gear ratio Use two speed crank Integrate second chain system with a high to low sprocket for higher overall ratios pedal-to-crank 20 overall speeds
45. Gear ranges Highest overall gear ratio: 55T-40T translated to 50T-11T 43.5mph at a pedaling rate of 90RPM 42.542ft of development/ revolution Drive ratio: 6.25:1 Lowest overall gear ratio: 55T-40T translated to 34T-28T 11.6mph at a pedaling rate of 90RPM 11.365ft of development/ revolution Drive ratio: 1.67:1
46. Braking System 15-0 mph braking distance: <20ft Stopping more mass than in typical bicycle application Options Rim Brakes Disc Brakes Hydraulic Disc Mechanical Disc Strong consideration to DH brakes
47. Brake Selection Mechanical disc brakes Advantages: Provide greater stopping power than most competitively priced rim brakes Much less expensive than hydraulic disc brakes No risk of boiling in high heat applications Can be adapted well to a 26” wheel hub Disadvantages: Front 20” wheel must be custom built with a disc brake compatible hub
48. Front Crank Arm Design Adjustable for different riders Withstand both torsional and axial cyclic loading with minimal deflection House bottom bracket for crankset House headset for steering system Integrate into bamboo frame Lightweight
50. Goals for Senior Project II Construct adjustable crank arm Determine ideal method to mount drive and driven sprockets beneath rider seat Obtain all necessary drivetrain components Construct custom front wheel Construct chain guides for 55-40T chain extension Develop lightweight kickstand to be integrated into fairing/ tub frame assembly
52. Rules Require frontal fairing, tail box, or full fairing Purpose: To Reduce aero dynamic drag When riding over 18 mph, drag accounts for over 80% of the forces acting to slow an unfaired bike. 1 Goals Reduce Aerodynamic Drag Fully Encompass Frame and Rider Stiff Light Minimize Cost Aerodynamic Fairing Gross, Albert C., Chester R. Kyle, and Douglas J. Malewiki. Aerodynamics of human-powered land vehicles. Rep. Professional Engineering, 2004.
53. Composite Sandwich Construction High stiffness-to-weight ratio compared to standard coreless composite laminate 2 Acts similarly to an I-beam Aerodynamic Fairing Vinson, Jack R. Behavior of sandwich structures of isotropic and composite materials. Lancaster, Pa: Technomic Pub. Co., 1999.
54. Common composite Sandwich materials Light Core material Structural Foam Balsa Wood Honeycomb Core Core Mat Laminate Bulker High Strength Composite Skins Fiberglass Carbon Fiber Kevlar Aerodynamic Fairing Composite Skins Core Material
56. Construction of Samples 12”x3.5” with positive camber Vacuum Bag Construction Creates strong bond between core and skin Removes excess resin Presses samples onto the form Aerodynamic Fairing – Materials Testing
63. Conclusions Core ¼” Diviney Cell Foam (2x1/8” for tight contoured areas) $50 more expensive Than 1/8” Foam for the whole fairing Held the most weight in all cases 22-30% Heavier than 1/8” Foam but 60-77% Stronger Composite Fiberglass held 10-20% less weight than Carbon Fiber ~4lb heavier for whole fairing. Able to Deflect 40%-60% more than Carbon Before Breaking 2-3 time less expensive then Carbon Fiber Aerodynamic Fairing – Materials Testing
64. Requirements Streamlined to reduce drag Fully enclose frame Allow for rider’s full range of motion Aerodynamic Fairing - Design
65. 2-D Sketch of Fairing Design Aerodynamic Fairing - Design
66. 3-D Model Made from 2-D Sketch Aerodynamic Fairing - Design
73. Sources 1: Gross, Albert C., Chester R. Kyle, and Douglas J. Malewiki. Aerodynamics of human-powered land vehicles. Rep. Professional Engineering, 2004. 2: Vinson, Jack R. Behavior of sandwich structures of isotropic and composite materials. Lancaster, Pa: Technomic Pub. Co., 1999. 4:Gupta, V. B., and V. K. Kothari. Manufactured Fibre Technology. New York: Springer, 1997. 5: "Hexcel.com - Fiber Glass Fabrics." Hexcel.com - Carbon fiber and composites for aerospace, wind energy and industrial. Web. 25 Dec. 2009. <http://www.hexcel.com/Products/Fabrics/Fiberglass/>. Aerodynamic Fairing
