Adjustable Linear Shock Absorber Redesign

1. Adjustable Linear Shock Absorber Redesign Matt Davis Joe O’Connor Ben Patterson Advisor: Mr. Lobaugh

2. Agenda • Sponsor Info • Contract Details • Design Problem • Analysis of Competitors Shock • Prototype Design Analysis • Final Design Analysis

3. Modern Industries • Founded in 1946 • Herbet S. Sweny • Industries Served • Machining • Heat Treating • Materials Research • Products Division

4. Products Division • Currently 7 Shocks • None adjustable • Custom for each customer • Our Project • Adjustable linear shock absorber • “Catalog Version”

5. Objective Statement • Study and reengineer an OEM linear shock absorber in order to provide a better working, more cost effective product that can be mass produced for a wide variety of commercial and industrial uses.

6. Specific Goals • Improvements: • Better functionality – Adjustment Method • Material/design improvements • More cost effective product

7. Scope & Limitations • Scope • 3D models and working drawings of new designs • Simulate and test with FEA • Research material changes • Limitations • Only redesigning OEM linear 1B model • Materials limited to commercially available materials

8. Deliverables • All concepts ideas • FEA results • Hand calculations to verify FEA • Working drawings of final design • Prototype

9. Upper Level Courses • MET 306 - Modeling • MET 320 – Hand Calculations • MET 415/425 – FEA of Designs • MET 432 – Internal Fluid • MET 457 – Product Improvements • MET 470 – Material Selection • QC 450 – FMEA

10. Gantt Chart

11. Industrial Shock Absorbers • Filled with hydraulic fluid • Designed to dissipate energy • Gradually bring a load to rest • Applications • Material Handling • Packaging Equipment • Small Robotics • Rotary Actuators

12. Design Ideas • Before deconstruction

13. Design Ideas Cont.

14. Analysis of Competitor Shock • Adjustment issues • Deconstruction • Testing • Physical • FEA

15. Deconstruction

16. Internal Fluid Flow • Compression • Extension

17. Competitors MTS Testing

18. Prototype MTS Testing (0.5Hz)

19. Energy Absorbed Comparison Data fit compared to linear regression Prototype: R2 = 0.832 Competitor: R2 = 0.4546

20. MTS Testing Comparison

21. Competitors FEA Hoop Stress Using Cylindrical Axis

22. Competitors FEA VonMises Stress

23. Improvements • Adjustment Methods • Material Improvements • Manufacturing Costs • Mounting Options

24. Prototype Design

25. Final Design

26. Final Assembly Outer Cylinder Foam Accumulator Stepped Insert O-Ring Check Valve O-Ring Piston Shaft Shaft Seal Inner Cylinder Top Cap

27. Final Design FEA Hoops Stress: Inner Cylinder Longitudinal Stress: Inner Cylinder

28. Final Design FEA Total Deformation: Inner Cylinder

29. Final Design FEA Hoops Stress: Stepped Shelf Insert Fluid Exit Point Stress - VonMises: Stepped Shelf Insert

30. Material Selection

31. Material Cost Analysis **All estimates based on McMaster Carr pricing

32. FMEA

33. Critical Components Pareto

34. Summary • Improvements • Manufacturing • Materials • Design • Deconstruction • Testing/Analysis • Prototype Design • Final Design

35. Questions Special Thanks to Mr. Michael for assisting with MTS testing

36. Supplemental Information

37. O-Ring Selection

38. External Force to Internal Pressure

39. Equation Used for Thick-Wall Pressure Vessel

40. Enidine Cylinder FEA Hand Calcs. For Hoop Stress

41. FEA Hand Calculations

42. Prototype FEA Compressive Stress: Piston Shaft Total Deformation: Piston Shaft

43. Prototype FEA Compressive Stress: Outer Cylinder Total Deformation: Outer Cylinder

44. Prototype FEA Contact Pressure Between Inner Cylinder and Insert Shelf

45. Outer Cylinder FEA

46. Competitors MTS Graphs (1Hz) Shock Setting 0 Shock Setting 3 Shock Setting 6 Shock Setting 8