Team 7: Vincent Borsello , Michael Brill, Daniel Gempesaw , Travis Mease Sponsor: Revenge Advanced Composites Adviso

1. Team 7: Vincent Borsello, Michael Brill, Daniel Gempesaw, Travis Mease Sponsor: Revenge Advanced Composites Advisor: Dr. James Glancey

2. Revenge Advanced Composites • Composites in marine applications • Industry-leading technology • Currently designing a new composite boat

4. Design a new composite shock mitigating marine seat and its manufacturing process • Problems with current seats: • Weight (metals), size • Tradeoff: shock mitigating seats vs. payload • Advantages of Composites • Lightweight • Strength only where needed

5. Seat • Attachment Mechanism • Damping Mechanism • Frame Shockwave Seat (144 lbs) Ullman Atlantic Seat (100 lbs)

6. Focus: Minimize the weight of the Support Structure while maintaining strength • Several parts were pre-selected by our sponsor, Revenge Advanced Composites • Semi-active shock absorber • The seat will be configured to match our design • Boat navigation Controls will be integrated into the prototype

7. 50% Weight Reduction • Relative to Shockwave Seat (144 lbs) • Dynamic Load Damping Capabilities • 20 G’s Vertical, 4 G’s Fore/Aft, 4 G’s Lateral • Product Life: 1400 working hours • ~150 instances of worst case vertical load • Reduced Footprint/Size • Less than 28 x 40 in^2 • Manufacturing • Best Practices for Pre-impregnated fibers (Prepreg)

8. Arm • C-channel • Base • Direct load path • Minimal footprint • Clevis • Integrate shock into design • Pivot Point • Bushing, Rod, Plates 3 1 4 2

9. Vertical ≈ 20 G’s • Dimensions & geometry • Force analysis of structure • Material Considerations • Strength and Stiffness • Curing/Outlife Characteristics • Weathering/Corrosion • Analyze all modes of failure (6) • Manufacturing Issues • Mold Designs • Ply Patterns Lateral ≈ 4 G’s Fore/Aft ≈ 4 G’s

10. Shape/Geometry of Structure Applied Loads Varying Thickness Capability Bolt Layout Bolt Sizes Washer Dimensions Bearing Size Pivot Point Mechanism Arm to Seat Attachment Structure to Boat Attachment Load Paths Composite Ply Layout Hole Distance From Edges Clevis Attachment Rider Comfort Material Selection Core Dimensions Adhesive Selection Support Plate Dimensions Seat Dimensions Hole Sizes Composite Manufacturability 8

11. Derive resultant forces in the entire system • Pivot point, shock mechanism, in arm & base Side FBD of Mechanism for illustration purposes

12. Knowing the forces in system, use stress and deflection analysis to derive thickness • Next step: consider critical areas Approximate arm & base as simple C-channels to calculate moments of inertia

13. d1 Shear Area Thickness=t • Inter-laminar shear • Compression • Failure modes for bolts: • Tension • Pull-out d2 Top-down view of base flange Depiction of Tear-out failure

14. X_a R_bearing R_rod Y_a Cantilever Arm • Pivot pin was found to fail due in tear-out • Low inter-laminar shear strength of composites • Solution: Bond on a metal doubler plate

15. Attachment of shock to arm & base • Designed to specifications of Active-Shock Side view of Clevis Plate Top-down view of Clevis Plate

16. De-molding • Draft Angle – 2 degrees • Bridging • Minimum Radius of Curvature – 1 inch • Vacuum Molding • Extending Mold Surfaces for Vacuum Bagging

17. 1 2 3 4

18. 5 7 6

19. 9 8 10 11

20. 12 14 13

21. 16 15 17

22. 19 18 20 Layup Mold Part

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25. All Target Values have been validated except for Fatigue Life. • Prototype Mold and Parts Cost: $20,000

26. Fatigue Tests • Different Materials • Carbon Fiber • Titanium • Bolt on Boat Testing • Target the lowest factor of safety • Different seat • Finish coating/ aesthetics

27. Stephen Andersen • Jim Glancey • Michel Lourdemarianadin • Hope Deffor • Steven Beard • Jon Sadowsky • RAC • Special Warfare Group 7