Detailed Design Review. P15611: Digital Microfluidics Packaging

Transcription

1 Detailed Design Review P15611: Digital Microfluidics Packaging

2 Presentation Summary - 1 Requirements/Test Plan Risk Assessment Individual Solutions System and Drawings Bill of Materials Schedule Questions/Discussion

3 Engineering Requirements - 2 Revisions: Droplet Size Updated to Reflect Reservoir Size Temperature Range Corrected

4 Testing Plan - 3 Some are straightforward: Reagent Ports, Max Weight Fluid delivery test will be straightforward due to new design Testing Humidity Accuracy seems challenging, procedures require specialist equipment

5 Safety Test - 4 Set-up enclosure and close so that the magnetic catch makes contact Confirm latch keeps enclosure closed Make sure no current is going inside of enclosure when open

6 Fluid Delivery Test Plan - 5 Set-up enclosure Pipette specified amount of fluid in capillary tube Confirm fluid can be drawn out by electrowetting

7 Microscope Compatibility Test - 6 Place whole enclosure under microscope Focus chip using light on microscope Confirm chip can be focused and there is clear resolution

8 Temperature Control Test - 7 Monitor temperature of enclosure Turn on cooling device Run for 5 minutes Record temperature over time Confirm temperature of enclosure is decreasing

9 System Test - 8 Deliver fluid to chip Set temperature Control droplet using GUI Confirm that whole system works together

10 Risk Assessment - 9

11 Risk Assessment: Humidity - 10 Reduce risk of condensation, to keep imaging clear Condensation occurs below dew point Assumed room relative humidities 20-60%, 75% worst case Calculated for temperatures between 6oC - 20oC

12 Risk Assessment: Humidity - 11 Relative humidity = partial pressure/vapor pressure We found the partial of air at a given humidity at room temp 60 and 75% relative humidity are extreme values Dewpoints at initial 60% RH have dewpoints around 13 C or 55 F

13 Risk Assessment: Condensation - 12

14 Risk Assessment: Safety - 13 Protect user from electric exposure Sugatsune - Electronic Magnetic Catch Detects when door is closed ( Power when on ) Aims to prevent power into the enclosure when open

15 Fluid Delivery: Original Solution - 14 SFC Quick Connects Work well with multiple ports Easy integration of reservoir Automated delivery Doesn't translate to multiple reagents Pressure controls involve fluid properties Tubing requires cleaning In the interest of future expansion we moved to a new concept

16 Fluid Delivery: New Solution - 15 SME: Dr. Michael Schrlau Eppendorf Microloader Tips Simple solution Easy to integrate into current Design Ability to use with pipettes in labs Seamless integration of new reagents Multiple reagents per test Minimal Chip Redesign Some difficulty of use in alignment

17 Cooling Analysis - 16 Cool a small enclosure and maintain temperature. Analysis of Free Convection Flow for flow of heat into the enclosure from the environment. Use of Nusselt and Rayleigh numbers for a horizontal plate. Constant and volume pressure assumed.

18 Cooling Analysis - 17

19 Cooling Analysis - 18 Used total resistance to find the heat rate in since surface temperatures were unknown. Convection rate of air based on film temperature less than 27 degrees from 0 C. Equated the inside using Lumped Capacitance Method. Biot was less than 0.1 Properties of air referenced from Tables.

20 Cooling Analysis - 19 The heat rate is dependent on the time. The faster the time the more power required. Qcool is in Watts, the temperature difference between the environment and enclosure is C. Heating requirement is at most 1 minute to keep heat rate low.

21 Cooling Analysis - 20

22 Heat/Cooling - 21 Cooling will be performed by a thermoelectric cooler. Capable of 6 watt rate. Thermoelectric waste heat output of approximately 10 watts. 40 x 40 mm square that is 5 mm thick.

23 Thermoelectric Cooling - 22 Peltier Plate Solid State Heat Pump +No Moving Parts or Fluid +Small Size -Low Power Efficiency -High Cost (Compared with Vapor Refrigeration) Small size accounts for some cons

24 Thermoelectric Cooling - 23 Plate gets cold on one side, hot on the other Heat management Material Concerns Works well in small enclosures Low amount of heat to remove Loses efficiency as heat rises Heat Management will be critical to effective application

25 Heat/Cooling - 24 Fits over thermoelectric and will act as seal. Non Ducted forced convection resistance of 0.82 C/W. Ducted forced convection resistance of 0.53 C/W 600 LFM or approximately 7 CFM Measures 45 x 45 x 25 mm

26 Heat/Cooling - 25 Fan capable of 7.0 CFM with 0.5 in H20 (~120 Pa). Overcomes any pressure loss from the heat sink. Will run off of 12V power supply. Measures 75 x 75 x 25 mm.

27 Heat/Cooling - 26

28 3D Printer Specifications - 27 Fortus 360MC 0.8 cubic foot build space Soluble or breakaway support structures ±0.127mm (±.005 ) achievable accuracy Available Materials ABSi ABS-M30,ABS-M30i ABS-ESD7 Nylon 12 PC-ABS PC,PC-ISO Ultem 9085 PPSF

29 Temperature & Humidity Sensor - 28 Adafruit HTU21D-F Temperature & Humidity Sensor Will report temperature & humidity data to computer Data can be incorporated into GUI to confirm experimental readiness Data can also be recorded to confirm experimental validity

30 Camera Stand - 29 Zykkor C082 Copy Stand Tripod Mount Head Adjustable Camera Base x 19 inch base inches tall 10 lbs of our 50 lb limit

31 CAD Model: Full Enclosure - 30

32 Assembly - 31

33 Fluid Delivery - 32 Leader for straight entry Tip lead for droplet positioning Microloader for use with standard micropipettes Tip Lead Microloader Leader Snap-in plugs Microloader Pipette Tip

34 Camera View Set-up - 33 Adjustable camera height for focus Universal DSLR adapter Possibility of modification for webcam use

35 Bill of Materials - 34 Indented BOM Includes: Part Description Vendor/Manufacturer information Quantity required Price (Including shipping) Lead Times

36 Bill of Materials - 35

37 Bill of Materials - 36

38 Lead Times D Printed Parts (Enclosure) - < 1 week McMaster-Carr (Glass, Gasket, etc.) - < 1 week Already Ordered - Camera Stand - 1 week Peltier Plate - < 1 week Heat Sink - < 1 week

39 Budget - 38

40 Budget:Estimated vs. Actual Cost - 39

41 Budget-Actual Cost Breakdown - 40

42 Schedule - 41

43 Questions/Discussion