Post on 14-Jan-2016
ME 489 Formal Design Review
September 22nd, 2004
Garrett DavisMatt MoodyArnar Thors
Background Info
• The Great Moonbuggy Race– NASA/Marshall Space Flight Center– US Space & Rocket Center– University of Alabama
• High School Student Customers– Vinemont High School
What is GMR?
• Human-powered
• 2 passengers – female & male
• Must collapse into 4’x4’x4’ volume
• 15” from ground
• 20 ft vehicle carry
• 20 ft turning radius
Customers
• Vinemont High School• 15 high school
physics students
• Political Implications– UA Recruitment– Vinemont HS Involvement– NASA Awareness
Customer Req’ts
• Adjustable Seat• Suspension/Stability• Lightweight• Rear Steer/Front
Drive• Comfortable Seats• Colorful• Single-gear drive
• One-Steer/One-Brake• Steering Wheel Type
(Primary)• Tires – Hoss-Daddy
Side-by-Side Seating
Concept #1
• Front/Rear WB• Cam-style Steering• Rear Drive/Derailleur • Triangle cross-section
frame
Concept #2
• Front WB/Rear Swingarm• Cable/Pulley Style Steering• Rear Drive/CVT Gearing • Square cross section frame
Concept #3
• Front Swingarm/Rear WB• Rear Rack & Pinion Steering• Front Drive/Derailleur w/ rev• I-Beam, T-shape frame
Concept Evaluation
Criteria Weighting Concept #1 Concept #2 Concept #3
Weight 20% 0.4 0.2 0.6
Safety 20% 0.2 0.2 0.5
Manufacturability 15% 0.23 0.23 0.45
Ergonomics/Comfort 5% 0.15 0.1 0.05
Size 10% 0.1 0.25 0.25
Simplicity 10% 0.1 0.25 0.25
Maneuverability 10% 0.2 0.1 0.3
Gearing 10% 0.3 0.2 0.1
Total 100% 1.98 1.53 2.5
Concept #3
Concept #3 Development
• Concept deviations– Change of frame cross-section– Derailleurs ditched for single speed– Reverse undecided– Independent swingarms changed to solid
• Further Development– All aluminum frame/suspension comp.– Adjustable seating position refined– Main frame structure reinforced
Concept #3 Development
• Major Areas of Concern:– Main Frame Member– Swingarm– Front Axle Sizing– Sustainability (common replacement parts,
fatigue analysis)– Shock/Spring Choice– A-Arm Geometry/Size– Balance/CG (ride height/weight distribution)– Cost Effective Material/Parts Choice– Cost Effective Fabrication Techniques
Future Plans8/29/04 9/5/04 9/12/04 9/19/04 9/26/04 10/3/04 10/10/04 10/17/04 10/24/04 10/31/04 11/7/04
Planning Meeting
Team Organization
Concept Generation
Customer Meeting
Concept Evaluation
Design Development
Formal Design Review
Parts Gathering
Design Review #1
Construction
Design Review #2
In-House Testing
Customer Testing
Final Adjustments (Repairs)
Design Review #3
Final Presentation
Future Plans
• Construction– Group-Wide Limitations– Intentions to Build Separate from UA
Engineering Machine Shop• Student Projects Building• Access to Shelton State facilities• Access to privately owned businesses/shops
– Individual Construction Schedule
Future Plans
• Procured Parts Listing:– Major Aluminum Frame Members– Minor Suspension Members– Tires/Wheels– Rack-n-Pinion – Steering Column & Wheel– Brake Caliper– Steering Linkages– Shock/Spring Selections– Seat Material
Conclusion
• Questions?