Space CadetsSpace CadetsAli JavedAli Javed

Ravneet Singh Ravneet Singh

Brock CouvillionBrock Couvillion

Dean SlamaDean Slama Temperature, Pressure, Humidity, and Imaging Characteristics at Various Altitudes

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MISSION GOALS

The goal is to study the relationships between the temperature, pressure, humidity, and altitude ranging from 0 to 100,000 ft in an effort to identify trends at various layers of the atmosphere using a balloon payload launched from Palestine, TX. 

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OBJECTIVESFly a balloon payload to an altitude of

100,000 ft to measure, record and verify temperature, pressure, and humidity trends.

Record video of the flight and verify the trends at various atmospheric layers.

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Science Objectives

Verify the decrease of temperature in tropopause

Verify the increase of temperature in stratosphere

Verify the decrease of pressure with altitude Verify the decrease in humidity with altitude. Identify the motion of flight.

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Earth’s Atmosphere

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Temperature

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Pressure

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MOISTURE

RAIN

• Amount of moisture the air can hold before it rains.

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HUMIDITY

LINEAR VOLTAGE SENSOR 30 SECONDS

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Areas that are elevated have a higher percentage of humidity compared to areas of lower elevation.

209 ft elevation653 ft elevation

20 ft elevation

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IMAGING CHARACTERISTICS

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System DesignSystem Design

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SensorsSensors

1N457 Diode Voltage across diode varies with temperature

HIH-4030 Humidity Sensor Output is linear voltage from .8-5V

Model 1230 Ultrastable Pressure Sensor Outputs Potential Difference Pressure Sensor

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1N457

.5 mA Current from LM234 CSOutputs Voltage Across Diode

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HIH 4030

5V Power from Voltage RegulatorLinear Voltage Output

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Model 1230 Ultrastable Pressure Sensor

1.5 mA from LM234 CS

ADC Ch 2

Output Potential Difference

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Camera Control Circuit

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Control SystemControl SystemBasic Stamp issues commands

Retrieves Values From ADC & RTC Writes to EEProm Sends commands to Camera

Camera Data stored in internal Memory

BASICStamp

Command toRead Signals

Data from Sensors

ADC

EEPromD

ata

from

AD

C,R

TC

RealTimeClock

Initi

aliz

e

Cur

rent

Tim

eD

ata

CameraCommands toStart/Stop

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Pre-Flight SoftwarePre-Flight Software

Flight SoftwareFlight Software

Data Retrieval SoftwareData Retrieval Software

SoftwareSoftware

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Pre-Flight SoftwarePre-Flight Software

Sets RTC

Sets Initial Address

Begin

Set Real TimeClock

Set initialSaved Address

Exit

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Initializes

Enters Sensor Reading Loop

Controls Camera

Flight SoftwareFlight SoftwareBegin

Read Real TimeClock

Read Saved Addressfrom EEProm.

EXIT

Create initial variables

Display Values toConfirm

Read Values fromRTC

Read Values fromSensors

Write Timestamp toEEProm & Increment

Address

Write Sensor Valuesto EEProm &

Increment Address

Save address toEEProm

Increment CameraControl Counter

CameraControl

Counter =40?

Pause for 30 Seconds

Is EEPromFull?

Send CameraStop Signal for

2 Seconds

Pause for 28 Seconds

Send CameraStart Signal for

2 Seconds

Reset CameraControl Counter

CameraControl

Counter =41?

No

Yes

No

Yes

Yes

No

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Determines First & Last Used Addresses

Enters Reading Loop

Data Retrieval SoftwareData Retrieval SoftwareBegin

Read Next SixAddresses

Display ConvertedValues

Exit

Set first address tofirst address definedin pre-flight software

CurrentAddress =

SavedAddress?

Read Saved Addressfrom EEProm

Yes

No

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Data Format & StorageStorageClock Values Storag

e Used

RTC-Hour 1 Byte

RTC-Minute 1 Byte

RTC-Second 1 Byte

Sensors:

Temperature Sensor 1 Byte

Pressure Sensor 1 Byte

Humidity Sensor 1 Byte

Total: 6 Bytes

12 * 240 = 2.88kb

At 12 Bytes a minute for 240 minutes,

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Power Supply

VOLTAGEREGULATOR

POWERSUPPLY 1

12 V

POWERSUPPLY 2

4.5 V

TEMP. SENSOR

HUMIDITY SENSOR

PRESSURESENSOR

BALLOONSAT

CCS

CCS

CAMERA

CAMERACONTROLCIRCUIT

3 V Back-UpBattery

(1 CR 2032)RTC

5 V

5 V

~ 1.5 mA

Op-Amp Circuit for thepressure sensor

Op-Amp Circuit for thepressure sensor

Op-Amp Circuit for thetemperature sensor

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Power Budget

Power Source 2: 3AA Lithium Battery Pack

ComponentVoltage (VDC)

Current (mA)

Flight Duration

Capacity (mA-hr)

Camera 4.5 300 4 1200

Power Source 1: 8AAA Lithium Battery Pack

ComponentVoltage (VDC)

Current (mA)

Flight Duration

Capacity (mA-hr)

BallonSat 12 150 4 600

Pressure Sensor 12 1.5 4 6

Temperature Sensor 1 1 1 4 4

(2)Transistor relay 5 1.85 4 ~7.5

Humidity Sensor 5 .5 4 2

Total 155.85 4 619.5

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Battery Derating CurvesBattery Derating Curves

AAA Lithium AA Lithium

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Thermal Design•Thermal test successful

•No additional heating system required

Component Minimum Operating Temperature

Maximum Operating Temperature

Basic StampBS2P24

-40 °C 85 °C

A/D ConverterADC0834

-40 °C 85 °C

MemoryEEPROM

-40 °C 85 °C

Real-time Clock DS1302

-40 °C 85 °C

Temperature Sensor PT303J2

-80 °C 150 °C

Pressure SensorModel 1230 Ultrastable

-40 °C 85 °C

Humidity SensorHIH-4030

-60 °C 140 °C

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Mechanical Design (External)Mechanical Design (External)

Nearly Cubical Nearly Cubical ShapeShape

18.5 cm * 15 cm18.5 cm * 15 cm 18 cm in height18 cm in height

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Mechanical Design (Internal)Mechanical Design (Internal) Camera mounted in Camera mounted in

bottom corner of bottom corner of shellshell

Power systems Power systems secured behind secured behind cameracamera

BalloonSat attached BalloonSat attached to one of the walls; to one of the walls; Conditioning board Conditioning board on opposite wallon opposite wall

3 sensors3 sensors

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Weight BudgetWeight BudgetComponent Weight(g) Clearance(g) Certainty of

Weight

BalloonSat 60 +/- 5 Measured

Primary Power (8 lithium AAA)

60 +/- 10 Calculated

Secondary Power (3 lithium AA)

46 +/- 5 Calculated

Backup battery for RTC 2.8 +/- 3 Measured

Foam Shell 95 +/- 5 Measured

Wires/Cables/Velcro 15 +/- 5 Estimated

Camera 133 +/- 5 Measured

Conditioning Circuit Board 60 +/- 10 Estimated

Total 471.8 +/- 48 Calculated

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System Testing ProceduresSystem Testing Procedures

Thermal TestProve payload function under extreme

temperature environments during 4 hour period

Shock TestProve payload resilience to force of free fall

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Calibration ProceduresCalibration Procedures

Calibration of temperature sensor

Calibration of pressure sensor

Calibration of humidity sensor

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Pre-Launch ChecklistPre-Launch Checklist

24 Hours Before Launch

Morning Before Launch

Post Flight

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Data Acquisition and Analysis Data Acquisition and Analysis PlanPlan

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Questions?

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