1. Moonbuggy ME Capstone Design Project SP 2006
By: Chris Haire
Brandin Ray
Beth DeShong
Andrew Wall
Vinay Prasad
Mentor: Dr. Jie Chen
Dr. S. Sivakrishnan

2. Reason For Design Improve Safety Increase Stability
Enhance Maneuverability
Enhance Mobility

3. Customer Requirements
Must fit within 48” Cube in Stowed Configuration
Light-Weight Design
Ride Height at least 15”
Human Power
Ease of Assembly
4’ Width when Assembled
30 Degree Incline without Tipping
Ensure Safety of Riders

4. Engineering Requirements
Light-Weight Design
Even Weight Distribution
Maximize Tipping Angle
20’ Turning Radius
Frame Stiffness
Short Assembly Time
Ground Clearance

5. Engineering Targets Buggy weight less than 200 lbs. 46” Width
15’ Turning Radius
Tipping Angle more than 30 degrees
1st Gear Ratio of 5:1 for Climbing
50/50 Distribution (front to back) & (side to side)
Max 5mm Deflection at Folding Point.
9 Seconds Assembly Time
Minimum 15” Rider Clearance

6. Product Development - Frame
Light weight design
Back to back seating
Center pivot makes for easy folding
Increased frame stiffness

7. Product Development - Subsystems
Drivetrain
2-wheel drive
Configured for back to back riders
Chain does not disengage when stowed
Rear Suspension
Redistribute forces to avoid single-point failure
Improve off-road and cornering capabilities

8. Final Product

9. Demonstration

10. Product Evaluation - Specifications
Buggy Weight (without riders) – 158 ¼ lbs.
Width – 44 ¾” (rear)
Ground Clearance – 8”
Rider Clearance – 22”

11. Product Evaluation – Specifications cont.
Weight Distribution - Front/Rear:
Weight Distribution - Left/Right:

12. Product Evaluation - Performance
Top Speed - 13 ± 1 mph (winner, 11 mph)
Turning Radius 6 ft
Lateral Acceleration – 0.74 ± 0.10 g’s
(10 mph & 9 ft turning radius at speed)
Gear Ratio – 0.44:1
Climb 35° Without Tipping (Climb / Traverse)
Deflection at Folding Point – 0.12 mm
Assembly Time – 28s

13. Engineering Targets vs. Product Performance
Targets Successfully Met
Weight is lb under
Width is 1 ¼” under
Turning radius is 9 ft under
Tipping angle over 35 degrees
Deflection is 0.12 mm compared to target of 5 mm.
Weight distribution within 10%
7” over minimum rider clearance
Improvements Needed for Targets
Does not meet lowest gear ratio requirement
Assembly time 24 seconds over initial target

14. Conclusion Major Accomplishments Designed and fabricated frame
Designed and fabricated rear suspension
Incorporated a 2-wheel drive design and unique drive train configuration
Fabricated and assembled completely new moonbuggy design at minimum cost
Built a safe, stable and rugged moonbuggy that can serve as a solid base for future teams