1. P13027: Portable Ventilator
Team Leader: Megan O’Connell
Matt Burkell
Steve Digerardo
David Herdzik
Paulina Klimkiewicz
Jake Leone

2. Technical Review Overview
Engineering Specs
Proposed redesign
Battery and Power Calculations
Power: Electrical
Electric Board Layout
MCU Logic
Pressure Sensor
Thermal Analysis
Housing Modifications
Project Comparison
Project Schedule
Questions?
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3. Engineering Specifications
Portable Emergency Ventilator
Engineering Specifications - Revision /19/13
Specification Number
Source
Function
Specification (Metric)
Unit of Measure
Marginal Value
Ideal Value
Comments / Status S1
PRP
System
Volume Control
Liters
0.2 ± 0.2 S2
Breathing Rate
BPM, Breaths per Minute
4 -15 S3
Pick Flow
Liter/Min S4
Air Assist Senitivity
cm H20
0.5 ± 0.5 S5
High Pressure Alarm S6
DC Input
Volts
6 - 16
Due to battery, must be greater than 9V S7
DC Internal Battery 12 S8
Elasped Time Meter
Hours S9
Pump Life
4500
S10
O2 / Air mixer O2
21% %
S11
Secondary Pressure Relief 75
S12
Timed Backup BPM
S13
Weight Kg
≤ 8
S14
Robustness
Drop Height
meter 1
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4. Revision B- Proposed Redesign
Update:
Battery Size-> Reduce Size & keep same capacity
Reduce Circuit Board size-> Create custom board for all electrical connects
Phase motor driver to a transistor
Display Ergonomics
Overall Size and shape of PEV
Instruction manual
Additions:
Visual Animated Display-> Moving Vitals
Memory capabilities
USB extraction of Data
Co2 Sensor as additional Feature to PEV
Overload Condition due to Pump Malfunction
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5. Revision B- Proposed Redesign
Update:
Battery Size-> Reduce Size & keep same capacity
Reduce Circuit Board size-> Create custom board for all electrical connects
Phase motor driver to a transistor
Display Ergonomics
Overall Size and shape of PEV
Instruction manual
Additions:
Visual Animated Display-> Moving Vitals
Memory capabilities
USB extraction of Data
Co2 Sensor as additional Feature to PEV
Overload Condition due to Pump Malfunction
NOT Discussed within Technical Review
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6. Battery Choice: Tenergy Li-Ion
14.8 V
4400mAh
lbs
7.35cm x 7.1cm x 3.75cm
Rechargeable up to 500 times
Price: $50.99
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7. Power Calculation Current (A) Voltage (V) Power (W) Pump 3 11.1 16.65
MCU + electronics
0.5
3.3
1.65
LCD
0.15 10
1.5
Total
3.65
19.8
Battery Voltage (V)
14.8
Battery Capacity (Ah)
4.4
Battery Capacity (Wh)
65.12
Expected Battery Life (Hrs)
3.29
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8. Charger (Brick) HP AC Adapter 18.5V 3.5Amps Power: 65W Max power: 70W
Price: $14.35 (Amazon)
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9. Regulation of Power
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10. Maxim Integrated MAX1737 Battery-Charge Controller
Wide input voltage range (6-28 V)
Charges up to four Li+ Cells (4- 4.4V per cell)
Provides overcharge protection
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11. Texas Instruments LM3940 Low Dropout Regulator
Provides 3.3V from a 5V supply
Low Dropout Regulator
Can hold 3.3V output with input voltages as low as 4.5V
Few external components needed for implementation
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12. ON Semiconductor MC7800 Voltage Regulator
5-18, 24 V Input voltage range
Can deliver output currents greater than 1 A
No external components needed for implementation
Internal thermal overload protection
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13. System Operation Flowchart
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19. Control System
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20. MCU Pinouts
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21. General PCB Parts Placement
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22. SpO2 Sensor
Difference in Absorption between Red and Infrared is used to determine SpO2
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23. SpO2 Sensor Continued
Simplified Design:
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24. SpO2 Flow Chart
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Source: Freescale Pulse Oximeter Fundamentals and Design

25. Hardware/Software Feature Implementation Plan
Function
Hardware
Software
User controllable ventilator control system 1
LCD Interface
Audio Feedback
Memory retention/ transfer 2
Touch Interface 3
Integrated Battery Charging
N/A
SpO2
CO2
Audio Recording
1- High Priority- This will get implemented
2- Medium Priority- Foreseeable difficulties may prevent proper implementation
3- Low Priority- Attempt to implement if time constraints allow
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26. Initial strategy for Testing
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27. Mass Flow Analysis (Between Pump outlet and Ventilator outlet)
Replacing Mass Flow Sensor with Venturi Analysis
Assume incompressible flow, 10 diameters of straight tube, C=.99
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28. Differential pressure sensor selection
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29. Freescale-mpxv5050dp Pressure Sensor
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30. Temperature Compensation
3.3 V
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31. Expected Pressure change & voltage output
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32. Expected Centerline Velocity
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33. EXPECTED Total Head Loss
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34. Expected Major Head Loss
Bernouli’s Equation Assumptions
Constant velocity, height and air density
Major Head Loss:
Dependent on length of tube between ventilator and pump exit
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35. Expected Minor Head Loss
Bernouli’s Equation Assumptions
Constant velocity, height and air density
Minor Head Loss
Dependent on the expansion and contraction for Reducer and Diffuser
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36. Exhaust Pressure Sensor
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37. Mechanical Relief Valve
Pressure Release at 1 psi  Reusable
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38. Thermal Analysis Heat Dissipation
GOAL: Analyze worst case thermal analysis of system to understand effects of system heat dissipation.
① System Components:
④ Control Volume Schematic:
② Applied Heat Loads:
PEV
③ Assumptions:
T∞=330K h= 5 W/m^2K (Applied to all surfaces)
Neglect Radiation
Casing acts as a control volume
System Location at hottest temp every recorded for U.S 330K
Heat flux is applied at bottom surface where all components will rest on.
Free External Convection
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Q flux=80 W

39. ⑤ Heat Dissipation Results:
High Temperature: 359 K
86 ⁰C
For our material, Polystyrene,
The glass transition temperature is 95 ⁰C. Therefore at worst case scenario, the material will hold shape without deforming.
Top of enclosure shows little heat transfer concern to handle so user can carry device. A rubber handle will be included on prototype as a precautionary measure as well as usability purposes.
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40. Another approach… ② Assumptions: ① Bottom Surface Heat Dissipation:
Component temperature is worst case.
System has been under worst case condition for extended period of time.
Neglect convection and radiation on bottom surface.
③ Results:
Plastic temperature at worst case will never exceed 120⁰F due to component heating alone.
This temperature is not enough to deform the polystyrene surface or cause damage to surrounding components.
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41. Housing Modifications
13026 Physical Extremes:
15in long X 10in high X 7in deep
Projected Physical Extremes:
12in long X 7.5in high X 7in deep
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42. Housing Modifications
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43. Housing Modifications
Speaker
Mode
O2 Sensor port
CPR Compression #
CO2 Sensor port
Manual
Mask tube ports
Power
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BPM
Flow Rate
Pressure Limit

44. Housing Modifications
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45. Housing Modifications
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46. Housing Modifications
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47. Housing Modifications
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48. Housing Modifications
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49. Project Comparison
GOAL: Analyze the size and weight reduction between major contributing components of MSD PEV to our projected design.
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50. Summary:
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51. 13027 – Project Schedule through MSD 1
Project Familiarization/ Research:
END OF
MSD 1
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52. Technical Evaluations/ Begin Prototyping:
END OF
MSD 1
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