1. Preliminary Design Review 02/24/2006 Team Members: Andrew Shabashevich, Greg Penoyer, Jessica Pierce, Tony Kukla, Bill Dugan, Gaurav Sanghi, Piyush Aggarwala Team Mentor: Dr. Edward Hensel Kate Gleason College of Engineering Rochester Institute of Technology Automated Bubble Elimination System Project #06219

2. Project Overview  Current visual inspection system falsely rejects contact lenses due to bubbles on lenses  Projected savings $1500/hr  Research and develop methods for eliminating bubbles on lens

3.  Design and build a stand-alone system to reduce the number of bubbles on a contact lens and in the water cell 75% Bubble Reduction 75% Bubble Reduction # of bubbles, total bubble surface area# of bubbles, total bubble surface area  Design the system with potential to be integrated into the automated production line (Freedial) machine at a later date Keep the same dimensional constraints Keep the same dimensional constraints Keep the same power/operating sources Keep the same power/operating sources Mission Statement

4. Phase 1 (Qualitative) Phase 1 (Qualitative) Test Fixture

5.  Meet cycle time of 4 s/cycle  Conform to FDA and clean room reg. Use of appropriate materials Use of appropriate materials  Maintain water cell design  Keep Freedial dimensional constraints  Meet Vision System requirements Lens orientation Lens orientation Settling time Settling time Project Parameters

6. ¾πr 3 ∆G v 4πr 2 σ αγ Nucleation Theory Understanding the Problem Homogeneous Heterogeneous

7. LaPlace’s Pressure Law Temperature (ºC) Surface Tension, σ (N/m) 07.56E-02 207.28E-02 606.62E-02 1005.89E-02 → ∑ F = Bubbles size is dependent on pressure Understanding the Problem

8. Rectified Diffusion “Area” Effect “Shell” Effect Diffusion rate into the bubble is greater then out of the bubble Understanding the Problem

9.  Vacuum  Ultrasound  Subsonic Frequencies  Rotary Motion  Water Recirculation  Electrical Potential Difference in Water  Surfactant and Surfactant/Vacuum  Changing Water Temperature  Physical Contact  Degassing the Water Initial Concepts

10. Feasibility Phase 1: Qualitative Analysis Testing Procedure  Developed crude testing prototypes to qualitatively test each of the concepts  Generated bubbles and placed lens in water cell  Took ‘before’ picture of lens  Applied process  Took ‘after’ picture of lens  Compared before and after pictures qualitatively Camera Water Cell and Cell Block

11. Vacuum  Vacuum Pump Pressure Pressure 7, 14, 20, 25, 27 inHg7, 14, 20, 25, 27 inHg Time Time 4, 8, 20 seconds4, 8, 20 seconds  5 samples for each trial Feasibility Phase 1: Qualitative Analysis

12. Vacuum  Vacuum (27 inHg) Before After 20 seconds of vacuum Feasibility Phase 1: Qualitative Analysis

13. Ultrasonic Setup  Ultrasonic Homogenizer Frequency of 20 kHz Power 15W Wand position 6 positions around water cell  5 samples for each position Feasibility Phase 1: Qualitative Analysis

14. Ultrasonic  Ultrasound (20kHz, 15 W) Before After 2 seconds Feasibility Phase 1: Qualitative Analysis

15. Subsonic Vibrations  24 VDC Motor  Off Center Mass  Variable 3 speeds Head Shape Tapered Rounded  5 samples for each trial Teflon Head Feasibility Phase 1: Qualitative Analysis

16. Subsonic Vibration Before After 3 seconds Feasibility Phase 1: Qualitative Analysis

17. Rotary Motion  24 VDC Motor  Variable 3 speeds Head Shape Tapered Rounded  5 samples for each trial Teflon Head Feasibility Phase 1: Qualitative Analysis

18. Rotary Motion Before After 3 seconds Feasibility Phase 1: Qualitative Analysis

19. Water Recirculation  Peristaltic pump  Variable Dispense volume 7 different volumes Time 2 and 3 seconds  5 trials for each flow Feasibility Phase 1: Qualitative Analysis

20. Water Recirculation Before After 2 seconds Feasibility Phase 1: Qualitative Analysis

21. Electricity  25 VDC Power Supply  Variables Voltage 10V, 20V, & 25V Electrode Position In liquid In liquid touching lens 3 Solutions used De-ionized water.1% Pluronic Surfactant Solution RENU Solution  5 samples for each trial Feasibility Phase 1: Qualitative Analysis

22. Electricity BeforeAfter 2 seconds Feasibility Phase 1: Qualitative Analysis

23. Analysis of Results  Concepts Eliminated: Surfactant aloneSurfactant alone Physical ContactPhysical Contact TemperatureTemperature ElectricityElectricity  Degassed Water Feasibility Phase 1: Qualitative Analysis

24. Weighted Feasibility Matrix (Post- testing) Feasibility Phase 1: Qualitative Analysis

25.  Ultrasound  Rotary Motion  Circular Flow  Concepts to be tested with and without degassed water Proposed Concepts

26. Design Objectives  Develop a test fixture to use with the Bausch & Lomb one-up inspection system  Fixture will be modular to quantitatively test the all final concepts  Fixture is easy to adjust and modify during testing Preliminary Design

27.  Semi Automatic Action  Pneumatic Actuator Raise and Lower module into cell Raise and Lower module into cell Stage slides on shafts Stage slides on shafts Preliminary Design Functionality

28. One-up Inspection System Inspection Camera Fixture Area Water Cell Slide Water Cell Switch

29. Rotary Module Parameters to Vary  Rotational Speed  Head Profile Lens Shape Flat Head  Immersion Depth

30. Flow Circulation Module Parameters to Vary  Adjustable Nozzles ID- 0.084”, 0.152”, 0.210” ID- 0.084”, 0.152”, 0.210” Immersion Depth Immersion Depth  Flow Rate 13 – 78 oz/min 13 – 78 oz/min

31. Ultrasonic Module Parameters to Vary  20 kHz Homogenizer Vary Power Vary Power  Immersion Depth Three depths between water surface and lens position Three depths between water surface and lens position

32.  Experimental Procedure Assemble Test Fixture Assemble Test Fixture Attach necessary assemblyAttach necessary assembly Method for creating bubbles Method for creating bubbles Shake container holding the lensesShake container holding the lenses Measure bubble reduction accurately Measure bubble reduction accurately Current Vision Inspection SystemCurrent Vision Inspection System Feasibility Phase 2: Quantitative Analysis

33.  Experimental Procedure cont. Develop general testing procedures Develop general testing procedures Consistent with process steps/parametersConsistent with process steps/parameters Control variables for each method Control variables for each method Acquire and analyze data Acquire and analyze data Identify and recommend appropriate method Identify and recommend appropriate method Feasibility Phase 2: Quantitative Analysis

34.  Initial Concepts were skimmed down to 3 Circulation, Ultrasound, Rotary Motion Circulation, Ultrasound, Rotary Motion Test with and without degassed water Test with and without degassed water  Evaluate concepts’ potential to remove bubbles  Meet customer requirements  Concepts are cost effective Conclusion

35.  Assess the 3 concepts in more detail by: DOEDOE Risk AssessmentRisk Assessment Cycle time/time studyCycle time/time study Cost Benefit AnalysisCost Benefit Analysis  Quantitatively prove concept feasibility  Propose final design(s) to B&L Timeline for Senior Design II

36. By the Week of March 20th  Build and debug test fixture  Get Vision System installed on the one-up  Develop testing matrix and DOE Throughout SDII  Begin in depth equipment and vendor research in parallel with testing  Pick final concept(s) by week of April 24 th Timeline for Senior Design II

37. Questions?