1. THE AVENGERS Measuring Atmospheric Ozone gases

2. General  The primary goal of the ITO sensor project is to measure the concentration of Ozone (O 3 ) as a function of altitude.  The concentration of these gases will specify the current situation of ozone depletion.  These measurements will be compared to past measurements made by other payloads.

3. Science  The ozone layer is the layer in Earth’s atmosphere which contains relatively high concentrations of ozone. This layer contains over 91% of the ozone in Earth’s atmosphere. It is mainly located in the lower portion of the stratosphere, from approximately 10 km to 50 km above Earth.  Halogens, the chemical family containing fluorine, chlorine, bromine, and iodine, have the ability to catalyze ozone breakdown.

4. Technical  The concentration of Ozone gases is calculated as the function of voltage produced across the ITO sensor.  As the resistance in the ITO sensor varies with the concentration of these gases, different voltages are produced with the same amount of input current in the circuit board.

5. System Design  Twelve volt supply powers all sensors  Two thermistors, two ITO sensors, four channels  Readings feed into ADC channels ADC sends data to BalloonSat EEPROM  ADC sends data to BalloonSat EEPROM  BasicStamp EEPROM also communicates with the BalloonSat EEPROM

6. Electrical Design and Development Sensors/Sensor Interfacing Control Electronics Power Supply Power Budget Electrical Development Plan

7. Sensors ITO Measures Ozone based on resistance across the sensor. As ozone increases, resistance increases. Provided by Dr. Patel of the University of North Florida THERMISTORS Two 1k Ohm thermistors. Measures temperature based off the resistance across the thermistor. As temperature decreases, resistance increases.

8. Sensor Interfacing

9. Control Electronics

10. Power Supply

11. Power Budget

12. Software Design Data Format and Storage Flight Software Software Development Plan

13. Data Format and Storage  BalloonSat EEPROM will store all data collected on flight (Yellow Circle)  BasicStamp EEPROM stores addresses for flight software (Red Circle)

14. Flight Software  Read “original address” from BasicStamp EEPROM  Add counter to data –1 byte  Read RTC –3 bytes  Read both thermistors and both ITO sensors –4 bytes  Store all data from reading  Store current address in BasicStamp EEPROM  Repeat loop until current address equals the original address –( current_address = original_address) –LED flashes once per second

15. Software Development Plan  Prototyping Software –Software must run without glitches –Software must successfully record correct data from input sensors  Data must be saved in a way that it will not be overwritten –Once software is completely functional, it will be optimized –Software will be uploaded to Excel, so it must be formatted  Prototyping Hardware –Electronics and Mechanical aspects should work with software –Temperature and Pressure Tests  Flowcharts –As the code is written and refined, flowcharts will be updated

16. Mechanical Design  A hollow regular hexagonal prism  FOAMULAR Insulating Sheathing External Design:  Each side of the base = 94 mm  The height of the prism = 175 mm  51mm X 49mm rectangular hole for the ITO sensor  The ITO sensor attached from the inner walls; minimal area of the ITO sensor is exposed The external design of ITO sensor payload (in mm)

17. Internal Design:  Rectangular- shaped foam (thickness = 18 mm) bisects the internal payload in two –Batteries, ITO sensor and Nichrome heater –BalloonSAT  Two chambers have different temperatures  Nichrome wire attached to the back of the sensor with thermal paste Internal Divider with BalloonSAT (in mm)

18. a) Side where ITO sensor is attached (in mm) b) Side where ITO sensor is attached with ITO sensor (in mm)

19. Weight Budget:  Balloon payload should be less that 500 g  Density of The FOAMULAR Insulating Sheathing =.029 g/ cm 3 S. N. Components Weight (gram) Clearance (g) 1.BalloonSAT60.4 +/- 10 2. FOAMULAR Insulating Sheathing 115 +/- 20 3. Power Supply (Battery) 121.9 +/- 25 4. ITO sensor and PCB 6.1 +/- 2 5. Components for Sensor Interface 35 +/- 15 6. Mass of cable for ITO sensor 17 +/- 3 Total:355.4 +/- 75

20. Risk Assessment Matrix

21. Looking Ahead  Critical Design Review due 3/30/2010  Liftoff! (Palestine): 5/25/2010

22. Special Thanks Dr. Nirmalkumar Patel