Team FEA Frame Engineering Associates Cal Poly SAE Formula Electric Chassis Final Report ___________________________ Brandon Stitt Rachel Brooks Christopher Pell 5 June, 2015 1 | P a g e Table of Contents Executive Summary ....................................................................................................................................... 8 Chapter 1: Introduction ................................................................................................................................ 9 Project Definition and Justification ....................................................................................................... 9 Suspension............................................................................................................................................. 9 Drivetrain ............................................................................................................................................ 10 Areas to Improve ................................................................................................................................. 11 Shape and Packaging .......................................................................................................................... 11 Manufacturing .................................................................................................................................... 12 Attention to Detail .............................................................................................................................. 12 The Senior Project ............................................................................................................................... 13 Chapter 2: Background ............................................................................................................................... 16 Current Frames and Designs ............................................................................................................... 16 Design Requirements and Specifications ............................................................................................ 19 Design Options .................................................................................................................................... 22 Concept Selection ................................................................................................................................ 25 Formula Electric Subsystem Placement .............................................................................................. 28 Space Usage ........................................................................................................................................ 28 Lateral ................................................................................................................................................. 28 Longitudinal ........................................................................................................................................ 29 New Car Layout Concepts ................................................................................................................... 29 Sidepod Configuration ......................................................................................................................... 29 Rear Motor Configuration ................................................................................................................... 30 Layout Verification .............................................................................................................................. 31 Adhesive Testing and Results .............................................................................................................. 34 Cockpit Mockup ................................................................................................................................... 37 FEA-Based Evolutionary Design in MATLAB ........................................................................................ 42 Zodiac Aerospace and Composite Sandwich Panels ........................................................................... 53 Sandwich Panel Testing....................................................................................................................... 55 Testing Setups ..................................................................................................................................... 56 2 | P a g e Testing Fixtures ................................................................................................................................... 58 Panel Failure Observations ................................................................................................................. 63 Results ................................................................................................................................................. 67 2015-16 Rule Changes and Rules Clarifications .................................................................................. 74 Cut-and-Fold Monocoque Design Evolution ........................................................................................ 75 Chapter 4: Description of the Final Design ................................................................................................. 79 Detailed Design Description ................................................................................................................ 79 Analysis Results ................................................................................................................................... 92 Cost and Weight Analysis .................................................................................................................... 96 Chapter 5: Manufacturing ........................................................................................................................... 98 Fiberglass Chassis ................................................................................................................................ 98 Carbon Chassis .................................................................................................................................. 100 Chapter 6: Design Verification .................................................................................................................. 114 Rules Required Tests: Descriptions and Results ................................................................................ 114 Senior Project Requirement Results .................................................................................................. 117 Chapter 7: Conclusions and Recommendations ....................................................................................... 120 Appendix A: QFD ....................................................................................................................................... 122 Appendix B: Drawing Packet ..................................................................................................................... 123 Appendix C: Vendor List ............................................................................................................................ 132 Appendix D: Supporting Analysis .............................................................................................................. 133 Appendix E: Gantt Chart ........................................................................................................................... 136 Appendix F: FMEA ..................................................................................................................................... 138 3 | P a g e List of Figures Figure 1.1: CAD of suspension Figure 1.2: CAD of drivetrain mounts only Figure 1.3: CAD of full drivetrain package Figure 1.4: SAE Car Coordinates Which Will Be Used Throughout This Report Figure 2.1: 2013-14 Cal Poly Formula Electric steel tube chassis. Figure 2.2: Carbon monocoque chassis. Figure 2.3: Cal Poly hybrid chassis. Figure 2.4: Aluminum monocoque formula chassis. Figure 2.5: Definition of the dimensions of the 95th percentile man. Figure 2.6: Broomstick test diagram. Figure 3.1: Matlab generated frame Figure 3.2: Full cut and fold monocoque design Figure 3.3: Formula shared tub design with cut and fold back Figure 3.4: CAD of Two Future Formula Electric Concepts. Figure 3.5: Samples from the Three Adhesive Testing Groups. Figure 3.6: Force-Displacement Curves of the First Two Adhesive Groups Figure 3.7: Force-Displacement Curves of the First Three Adhesive Groups Figure 3.8: Illustration of the Peeling Deformation Caused by a Rivet in Test Group 4 Figure 3.9: Force-Displacement Curves of All Four Adhesive Groups Figure 3.10: Front View of Entire Cockpit Mockup Figure 3.11: View of Cockpit Mockup Showing Seat Mounting, Top Tube Mounting, and Steering Wheel Figure 3.12: Double Bracket System to Allow Rotation of Vertical Mockup Components Figure 3.13: Pedals in Cockpit Mockup Figure 3.13a: Top Side Impact Tube in Cockpit Mockup Figure 3.14: Dimensioned Sketch of Final Cockpit Mockup Figure 3.15: Deformed FEA Result in MATLAB Figure 3.16: SolidWorks and MATLAB FEA on a Sample Tube Structure Figure 3.17: MATLAB Program Scoring Method Flowchart Figure 3.18: Overall MATLAB Program Map Figure 3.19: Weight and Score Change Across 80 Generations Figure 3.20: Maximum Deflection Change Across 80 Generations for 7 Loading Cases Figure 3.21: Maximum Rotation Change Across 80 Generations Figure 3.22: Maximum Deflection of Rear Side Impact