Final Progress Report
David Baker, Adam Baldan, Matthew
Grusenmeyer, Evan Jenkins, & Shane Marcks
• An international collegiate competition regulated by the Society of Automotive Engineers • Build an open wheel race car to participate in both design and dynamic competitions • The UD Formula SAE team will compete in the 2011 FSAE West competition in California
http://www.sdsefi.com/techfsae.htm
Design, Fabricate, and Test a Steel Space Frame Chassis and Fuel System
High considerations to manufacturability
On par with top teams’ performance
• Torsional and Flexural Rigidity
• Weight
• Center of Gravity Height
Seamlessly Integrate all critical System Components
Resources
• Steel Tubing
Cost (<$1000)
Wants • Minimize the weight to stiffness ratio
• Maintain Low Center of Gravity
• Reasonable material and manufacturing costs
• Create a solid base chassis to evolve on for years to come
• Aesthetically pleasing design
Needs • Purposefully integrate all car systems including drivetrain,
driver controls, and suspension together
• Efficiently locate/design or select a fuel tank
• Create a cockpit that can accommodate up to a 95th percentile male
All vehicle systems must fit onto the chassis • Suspension Members, Engine, Fuel Tank, Differential,
Axles, Pedals, etc…
Must comply to all 2011 Formula SAE rules for • Safety
• Geometry
• Materials
Maximum cost of $1000, less donated parts/tools/materials
Top Teams of 2010 FSAE Competitions as well as our Previous Chassis • Rigidity
• Weight
• Type of Chassis (Composite, Steel, Hybrid)
Consultations with CCM Faculty • Dr. Suresh Advani, Dr. John Tierney, Pit Schulze, and Dr. Dirk Heider
Manufacturability
Longitudinal
Torsional Rigidity
Flexure
Resistance
Weight
Reliability
Aesthetics
Vertical Center of
Gravity
Metric Target Values
Metric Target Value
Manufacturability 225 Hrs
Longitudinal Torisonal Rigidity 1800 Foot Pounds per Degree
Flexure Resistance 4500 Pounds per Inch
Weight Under 75 Pounds
Vertical Center of Gravity Under 10 Inches
Our research has shown three prevalent designs in FSAE racing:
Steel Space Frame
• Current standard in FSAE
• Low cost, manufactured with conventional tools
• Easy to repair and modify
• Low strength/weight ratio means a heavier structure
Full Monocoque
• Pinnacle of racing technology – only type used in Formula 1 Racing
• Enhanced strength/weight ratio over steel frames
• Exotic materials add cost, difficult to manufacture
• Difficult to repair/modify, poor accessibility to critical systems
• Difficult to obtain sufficient pull out strength at mount points
Hybrid Monocoque/Spaceframe
• Realize benefits of monocoque while avoiding rear mounting
complications
Tubing Summary
Material Tensile Strength (ksi) Yield Strength (ksi) Appr. Cost ($/ft.)
SAE1010 ERW 45 – 50 30 – 35
1 x 0.049 0.48
1 x 0.65 0.45
1 x 0.095 0.65
SAE1020 DOM 80 – 90 70 – 80
1 x 0.049 1.05 – 1.92
1 x 0.65 1.35 – 2.05
1 x 0.095 1.42 – 2.45
SAE4130 DOM 90 – 100 80 – 90
1 x 0.049 1.96 – 2.45
1 x 0.65 1.90 – 2.38
1 x 0.095 2.79 – 3.57
Design Considerations
Torsional and Flexural Rigidity along the length of the vehicle
Triangulated Sections
Accommodation of Driver and Major Systems
Notching
Tubing bending for Roll Hoops
Welding
Pros: - Based off existing frame - Revised load paths - Lighter than existing frame - Expanded roll hoops for more
driver comfort and accessibility
Cons: - Heavier than Monocoque Designs
Pros: - Realizes the structural benefits
of monocoque construction - Lighter and more aesthetically
pleasing than a space frame with bodywork
- Avoids packaging, manufacturing and accessibility challenges of a full monocoque
Cons: - Difficulty of achieving proper
pull out strength of critical connections
- Limited pedal box Accessibility - General mounting of peripheral
components is a challenge
Design Considerations
Pull out strength of critical connections (>17kN)
Pedal Box Accessibility
Manufacturability of Mold and Foam Core
Joining Rear Steel Frame to Front Composite Monocoque
General Mounting Points of Various Components
• Composite monocoque structure from firewall forward
• Steel space frame utilized for the rear section
Utilized concept selection Matrices
Concepts vs. Weighted Wants, Weighted Metrics, and Constraints
Conclusion
Hybrid Monocoque/Space Frame
The hybrid form utilizes the exceptional weight to stiffness properties and the sleek appearance of a composite monocoque, while maintaining the ease of component mounting and adjustability of a steel frame.
Carbon Fiber Sample Testing ◦ Test panels with
donated materials did not have sufficient mechanical properties to allow for use in chassis
◦ Change was made from
Hybrid Frame concept to Steel Frame concept Driven by poor material
performance
Wooden Spine Jig Flat Tube Profile Patterns
Weight
Center of Gravity
Rigidity (Torsional & Flexural)
Manufacturability 450hrs
Torsional Test Rig
Torsional Test Rig
Part: Price: ($) Notes: Fuel Pump 80 Stock Yamaha Electric Fuel Pump, bracket and o ring
Fuel Lines and Fittings 30
Space Frame Material 350 10-20DOM tubing already purchased
Body Work Materials 0 Donated by CCM Suspension Mounting
Materials 35 Returned Mounts
Fuel Cell Aluminum 60 3’X3’ 1/16 sheet of aluminum
Wood For Frame Jig 50 For manufacturing of tube frame
Engine Bushings 30 4 Bushings
Bimetal Hole Saws 40 1 inch hole saws
Tube Clamps 90 For manufacturing of tube frame Body Work
Manufacturing 100 Foam and wood to build mold
Paint for Frame 50 Rustoleum and Clear Coat
Total: 915