Loading Apparatus for High Velocity Tissue Rupture

1. Loading Apparatus for High Velocity Tissue Rupture Mechanical Engineering Dalhousie University Senior Design Project Winter 2010

2. Group 12 • Geoff Beck • Ben Breen • Ruth Domaratzki • Rachael Schwartz

3. Supervisor Client • Dr.Kujath • Mechanical Engineering Dalhousie University • Dr. Lee • Biomedical Engineering Dalhousie University

4. Presentation Outline • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations

5. Background • Application: • Determine the mechanics of high-speed failure for a biological specimen • Simulate impact trauma • Presently: • Dalhousie BME, emax = 10 s-1 • Limited by servo-hydraulic actuation method • Desired: • To overcome current tensile testing limitations. • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions

6. Final Design • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions

7. Final Design: Grip and Housing • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions

8. Final Design: Drive Shaft Assembly • Contents • Background • Design Requirements • Design Selection • Selected Design • Budget • Future Considerations • Conclusions • Questions

9. Final Design: Engagement Pin • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions

10. Final Design: Engagement • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions Disengaged Engaged

11. Final Design: Engagement • Use optical encoder to determine pin position • Functions using IR sensor • Encoder has one hole located (180º) opposite pin • position • Able to sense when pin has passed solenoid • Ensures the solenoid does not engage pin in a • partial contact scenario • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions

12. Final Design: Safety • Minimize rotating masses. • Encase in polycarbonate shield. • No controls in immediate area. • Started and Controlled via DAQ. • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions

13. Final Design: Measurement Systems • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions

14. Final Design: Measurement Systems • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions

15. Final Design: Measurement Systems • Verification of LVDT data included • implementing high speed video to • determine velocities • Flywheel angular velocity was verified • comparing the controller output to the • strobe frequency • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions

16. Final Design: Measurement Systems • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions

17. Testing and Performance • Tested bovine pericardium tissue. • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions

18. Testing and Performance • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions

19. Testing and Performance • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions

20. Testing and Performance • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions

21. Testing and Performance • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions Shadwicke RE. Mechanical Design in Arteries. K Exp. Biol. 202, 3305-3313, 1999.

22. Testing and Performance • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions

23. Testing and Performance • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions 1000RPM – 1000fps

24. Testing and Performance • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions 500RPM – 500fps

25. Design Requirements • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions

26. Design Requirements • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions

27. Design Requirements • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions Total Design Requirements Met: 7/10

28. Budget • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions

29. Future Considerations • Substitute stainless steel in place of plastic bath • Reduce mass of moving parts in an effort to reduce inertia • Reduce moment acting on engagement pin • Create dedicated circuit boards or shield electrical components to reduce crosstalk • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions

30. Conclusions • Constructed a device that in the future will lead • to a better understanding of tissue mechanics • Satisfied with dynamics and control of device • Several design features that our client will • continue to refine and develop • Gained valuable knowledge and experience • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions

31. Acknowledgements Special Thanks To: Dr. MarekKujath Dr. J. Michael Lee Mark, Angus, and Albert Dr. Julio Militzer Dr. Darrel Doman Jon MacDonald Peter Jones

32. Questions? Senior Design Project Team 12 Dalhousie Department of Mechanical Engineering Winter 2010

34. Mechanical / Electrical Crosstalk

35. Solenoid Selection and Performance

36. Final Design: Measurement Systems • Machine Status: • Angular velocity of the flywheel • Position of the rotating impact surface (pin) • Experimental Variables: • Specimen stress • Standard strain gauge load cell • Specimen displacement • Linear Variable Differential Transformer • Contents • Background • Final Design • Testing and Performance • Design Requirements • Budget • Future Considerations • Conclusions