Transcript orion.bme.columbia.edu

Green Dot Technologies
ELIJAH LI
VICTOR MATEAS
HODA RIFAI
ROMAN STOLPER
THEA ZIMNICKI
 Pharmaceutical Storage Problems in Developing
Countries:

Vaccine spoilage often occurs at vaccine provider’s site
Unreliable power grids
 Untrained and overworked healthcare workers


Administration of spoiled vaccines
= LOSS OF LIFE AND LIMITED RESOURCES
 We will design a refrigerator accessory which will:
 Minimize cold loss during refrigerator usage
 Minimize power consumption
 Inform against administration of spoiled pharmaceuticals
 Simplify inventory system
 Goal: Retain Cold Temperature
 Conduction
Thickness of materials
 Thermal conductivity of materials


Convection

Decrease flow of warm air into fridge
 Dual layer
 Design of drawer
 Goal: Increase Energy Efficiency
 Energy use related to internal temperature
 Oscillation of cooling and non-cooling cycles used to keep
temperature within acceptable range
 Purpose



Physical model of
prototype to build
Run thermal analyses
Extrapolate to other
environments
 Next Step

Convection
Requires air flow rate
 Empirically determined

 Clamp


Tighter seal around door
Creates active role for user to avoid partial closure
 Magnetic Strip

Magnet on the drawer dividers to ensure drawer opens correctly


Helps user avoid leaving inside exposed to atmospheric conditions
Additional magnets on front panel of drawer

Helps hold drawer tightly to the front of fridge attachment
 Temperature Monitoring


Green LED lets the user know that the vaccines are in the optimal
range and not at immediate risk
Red LED informs of spoilage


Temperature above 8 °C or under 2 °C
Yellow LED tells user to use vaccine as soon as possible

Temperature between 7 and 8 °C or 2 and 3 °C
 Inventory Mechanism

Allows user to avoid opening drawers unnecessarily



Vial’s weight presses metal conductors together to close one part of the
circuit
User presses button to close second part of circuit
LED’s activated when entire circuit closed
Testing
 Power Consumption Test

Rewired energy meter to
measure watts used
 Temperature Test

Used DAQ to measure
temperatures of 3
thermistors over time
 Temperature Monitor


Used a microprocessor to
output signal from 3 precise
thermistors to an LCD
Will be used in prototype to
output to LEDs
Proof of Principle Tests
Temperature
Pow er On, Door Closed for Three Hours
Purpose
 To show how temperature
and energy use are related in
a standard refrigerator
Time
Pow er On, Door Closed for Three Hours
 To find conditions to isolate
for potential improvement
Watt
 To compare prototype to a
standard to show that goals
have been met
Time
Proof of Principle Tests
Power On, Door Opened/Closed for 1 hour
Next Steps
Temperature
 Determine flow rates for
SolidWorks empirically
using tubes and a pump to
mimic air flow
Time
Pow e r Off, Door Ope n/Clos e for 50 m inute s
 Run longer term tests
 Conduct same tests on all
Temperature
prototypes
 Compare efficacy of
adjustments in prototype to
capitalize on improvements
Time
Phase 2
Phase 1
1. Fabrication of
Prototype
1. Temperature and
Power Consumption
Testing on Prototype
2. Compare Results
against Current Fridge
Phase 3
1. Complete
SolidWorks Model
2.Test and Implement
Further Improvements
Professor Sam Sia, Faculty Advisor
Professor Gordana Vunjak-Novakovic
Professor Elizabeth Hillman
Keith Yeager
Brenda Chen
Dr. Timothy P Martens