THE AVENGERS

1
THE AVENGERS

• Measuring Atmospheric Ozone

1 of 25
2
General

• The primary goal of the ITO sensor project is to
  measure the concentration of Ozone (O3) 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.

2 of 25
3
Science

• The measurement from the sensor is done as the
  function of physical quantities as the sensor
  might function in a different way depending on
  the altitude, temperature, humidity and pressure.
  
• The obtained measurements are compared with
  various experiments showing the precise
  concentration of Ozone.
• Different halogens, such as Flourine, Chlorine,
  and Iodine have been used to accelerate this
  process.

3 of 25
4
Technical

• The concentration of Ozone is calculated as the
  function of voltage produced across the 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.
• The Real Time Clock will be utilized as a counter
  and a timestamp will be printed for each
  measurement so that it can be related by time to
  altitude.

4 of 25
5
System Design
6 of 25
6
Electrical Design and Development

• Sensors/Sensor Interfacing
• Control Electronics
• Power Supply
• Power Budget

5 of 25
7
Sensors/Sensor Interfacing
7 of 25
8
Control ElectronicsBalloonSAT
8 of 25
9
Nichrome Heater
9 of 25
10
Power Supply
10 of 25
11
Power Budget
11 of 25
12
Software Design

• Data Format and Storage
• Flight Software
• Software Development Plan

12 of 25
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)

13 of 25
14
Flight Software

• Read original address from BasicStamp EEPROM
• Add counter to data
• 1 byte
• Read RTC
• 3 bytes
• Read all 4 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

14 of 25
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

15 of 25
16
Thermal Design

• ITO Sensors must maintain temperatures between 24
  and 30 degrees Celsius
• Nichrome wire _at_ 22.3 ohms/m
• Requires approximately 2.5W

16 of 25
17
Mechanical Design

• A hollow regular hexagonal prism
• FOAMULAR Insulating Sheathing
• External Design
• Each side of the base 94 mm
• The height of the prism 193 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 m)
17 of 25
18

• 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 m)
18 of 25
19
a) Side where ITO sensor is attached
(in m)
b) Side where ITO sensor is attached with ITO
sensor (in m)
19 of 25
20

• Weight Budget
• Balloon payload should be less that 500 g
• Density of The FOAMULAR Insulating Sheathing
  .029 g/ cm3

S.N. Components Weight (gram) Clearance (g)
1. BalloonSAT 60.4 /- 5
2. FOAMULAR Insulating Sheathing 115 /- 20
3. Power Supply (Battery) 178.8 /- 25
4. ITO sensor and PCB 6.1 /- 2
5. Components for Sensor Interface 35 /- 15
6. 7. 8. Mass of cable for ITO sensor Nichrome Wire and thermal paste Tape, Glue and other structure 17 3 20 /- 3 /- 2 /-5
Total Total 435.3 /- 77
Approximated within 0.1g
20 of 25
21
Calibrations
21 of 25
22
Ground Software

• Save into text file
• Use Microsoft Excel
• Algorithms pre-programmed

22 of 25
23
Risk Management
23 of 25
24
Looking Ahead

• Flight Readiness Review (FRR) 5/4/2010
• Liftoff! (Palestine) 5/25/2010

24 of 25
25
Special Thanks
25 of 25