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Ali Javed
Ravneet Singh
Brock Couvillion
Dean Slama
Space Cadets
Temperature, Pressure,
Humidity, and Imaging
Characteristics at Various
Altitudes
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.
OBJECTIVES

The objective of this project is to fly a
balloon payload to an altitude of 100,000 ft
to measure, record and verify temperature,
pressure, and humidity trends. Also,
record video of the flight and verify the
trends at various atmospheric layers.
Science Objectives
Verify the decrease of temperature in
tropopause
 Verify the increase of temperature in
stratosphere
 Verify the decrease of pressure with altitude
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Verify the decrease in humidity with altitude.
Identify the motion of flight.
Earth’s Atmosphere
Temperature
Pressure
• Amount of moisture the air can hold before it rains.
MOISTURE
RAIN
LINEAR VOLTAGE SENSOR
30 SECONDS
209 ft elevation
20 ft elevation
653 ft elevation
Areas that are elevated have a
higher percentage of humidity
compared to areas of lower
elevation.
IMAGING CHARACTERISTICS
System Design
Sensors
 IN457
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Diode
Voltage across diode varies with temperature
Low output range.
Requires constant current
 HIH-4030
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Humidity Sensor
Powered by 5V
Output is linear voltage from .8-3.5V
 Model
1230 Ultrastable Pressure
Sensor

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Requires 1.5 mA Power
Outputs Potential Difference
Signal Conditioning
Op-Amps condition
signals to match
range of ADC
Sensor
Conditioning
Circuit
Balloon Sat ADC

Control System
Basic Stamp issues commands

Retrieves Values From ADC & RTC
Writes values to EEProm
Issues commands to Camera

Camera Data stored in internal Memory
Real
Time
Clock
ADC
Command to
Read Signals
Data from Sensors
Initialize

BASIC
Stamp
Data from ADC,RTC

Current Time
Data

EEProm
Commands to
Start/Stop
Camera
Flight Software
Initialize
Set RTC,
Tell camera to begin
recording
Increment
Loop Counter
*Initialize
*Take readings every 30
seconds and writes to
EEProm
*Control Camera
Read Time from
RTC
Read Sensor
Values from ADC
*Prevent memory overflow
Write to EEProm
Check Camera Status
If loop counter = 40, stop recording.
If camera loop counter = 41, begin
recording and reset counter to 0.
Pause
Check If
EEProm
Memory Full
Stop
Power Supply
1.5mA
PRESSURE
SENSOR
CCS
5V
~ 1 MA
CCS
HUMIDITY SENSOR
TEMP. SENSOR
VOLTAGE
REGULATOR
BALLOONSAT
RELAY
(2)
CONTROL SIGNAL
POWER
SUPPLY 1
12 V
POWER
SUPPLY 2
4.5 V
CAMERA
CONTROL
CIRCUIT
CAMERA
Power Budget
Thermal Design
Need to do a thermal test of
internal operating
temperature in a lowtemperature environment
For now the assumption is
that the operating
electronics will generate
enough heat to maintain
proper operating
temperatures above -40
degrees Celsius
Component
Minimum
Operating
Temperature
Maximum
Operating
Temperature
Basic Stamp
BS2P24
-40 °C
85 °C
A/D Converter
ADC0834
-40 °C
85 °C
Memory
EEPROM
-40 °C
85 °C
Real-time
Clock DS1302
-40 °C
85 °C
Temperature
Sensor
PT303J2
-80 °C
150 °C
Pressure
Sensor
Model 1230
Ultrastable
-40 °C
85 °C
Humidity
Sensor
HIH-4030
-60 °C
140 °C
Mechanical Design (External)

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Nearly Cubical
Shape
18.5 cm * 15 cm
18 cm in height
Mechanical Design (Internal)
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Camera mounted in
bottom corner of
shell
Power systems
secured behind
camera
BalloonSat attached
to one of the walls;
Conditioning board
on opposite wall
3 sensors