A manufacturing process study for a formula style racecar chassis. Project\'s objective was to reduce manufacturing costs by simplifying certain parts of the frame while maintaining satisfactory rigidity.

1. ME 138: Formula SAE Chassis Final Design Jed Escovilla Joe Fini Ben Ly Jesse Thompson Gustavo Ortiz

2. Goals and Ideas 2010 Chassis Torsional Rigidity: 370 lb-ft / degree The Use of FEA

3. F-SAE 2010 Chassis: Weight Weight: Under 63 lbs The Lighter The Faster

4. F-SAE 2010 Chassis: Comfort Drivers Seating Angle & Front Hoop: Increase Comfort and Ease Driver Egress

5. Concurrent Engineering Principles Used Design for Manufacturing Design for Cost Design for Serviceability

6. Design for Manufacturing Redesigned frame has reduced amount of welded joints Reduced the number of tubing for the frame

7. Redesign of Front Hoop 2009 front hoop had too many butt welded joints, these are replaced with bends.

8. Reduction in Frame Tubing Removed tubing from engine mounting structure

9. Design for Costs Manufacturing Costs were reduced by : Replace welds with bending when possible Reducing number of tubes for frame Material Costs Steel used for frame increased but only by a small amount to make up for loss rigidity.

10. Design for Serviceability Main hoop bracing redesign for engine serviceability.

11. FEA Analysis and testing

12. Torsional Rigidity Without proper rigidity significant frame bending occurs (strain) With major flexing in the frame, clearances will be affected Frame flex induces forces not originally intended

13. Torsional Rigidity testing Ft-lbs Units: degree

14. 2010 Frame Rigidity

15. Race Conditions Simulation Applying loads during race conditions Most extreme case: Turning

16. FSAE Autocross Conditions D7.2 Autocross Course Specifications & Speeds D7.2.1 The following standard specifications will suggest the maximum speeds that will be encountered onthe course. Average speeds should be 40 km/hr (25 mph) to 48 km/hr (30 mph). Straights: No longer than 60 m (200 feet) with hairpins at both ends (or) no longer than 45 m (150 feet) with wide turns on the ends. Constant Turns: 23 m (75 feet) to 45 m (148 feet) diameter. Hairpin Turns: Minimum of 9 m (29.5 feet) outside diameter (of the turn). Slaloms: Cones in a straight line with 7.62 m (25 feet) to 12.19 m (40 feet) spacing. Miscellaneous: Chicanes, multiple turns, decreasing radius turns, etc. The minimum track width will be 3.5 m (11.5 feet). F=20.5slugs*44ft/s^2/29.5ft = 1,331 Pounds of Force OR (66ft/s^2)/(32.2ft/s^2)=2 *Gs

17. COST

18. FSAE Cost Guidelines Cost Event – The Cost Event Rules (abbreviated) 1. Standardized Prices – The prices for parts, materials and processes have been standardized and the prices in the official Cost Tables must be used. If you use a part or process that’s not in the table there is a procedure for having it added. The standardized Cost Tables will be published through the FSAE website. 2. No Receipts – Since prices are standardized no receipts are required – except when requesting items be added to the table. 3. No Maximum Cost – You can spend as much as you like on your FSAE car with the understanding that your total cost is a significant factor in your Cost Event score.

20. Material Costs:- frame weight = 63.25 lbm - standardized cost = $4.95/lbm - material cost = $313.09

21. 2010 Cost Manufacturing Standardized Costs: Tube prep = $0.75/end Tube cut = $1.20/end Tube weld = $1.20/end Tube bend = $0.75/bend

22. 2010 Cost Manufacturing Costs - 114 welds = $136.80 - 8 bends = $6.00 - 114 tube preps = $85.50 - 114 tube cuts = $136.80 - Total = $365.10

23. 2010 Cost Materials Cost = $313.09 Manufacturing Cost = $365.10 Total = $678.19

25. Less Manufacturing Costs

26. More bends

27. Reduces the number of tube ends to be notched and welded

29. Total Savings $ 41.21 ~5.7% Any Questions?