Metropolitan State UniversityIsaac Hamilton
Jordan Gallegos
Christopher Olson
McMillan Miskin
Daniel Koch
Thomas Mindenhall
Cody Overcash
March 27, 2009
Outline Mission Overview Payload Compliance Payload Design Balloon Interface Heating System Camera System Accelerometer System Structural and Thermal Properties Testing and Results Price List
Mission Overview
Our objective is to send a weather balloon with a payload to an altitude of one hundred thousand feet. It will capture still photographs and record acceleration forces during the three-hour flight as well as subsequent impact with the ground.
The team expects to meet all objectives while maintaining a budget of eight hundred dollars.
Amateur high altitude weather balloons are becoming more popular. Many people have used weather balloons to obtain dust samples and also to take aerial photography from the edge of space.
Payload User Guide Compliance
Mass- 1.5 kg (Total Payload) Payload mass is 1.368kg
Determination of G-loads upon landing Accelerometer is capable of measuring 3 G’s at a rate of 1 sample
every 0.6 seconds totaling 18000 measurements during the flight
On-board photography during entire flight Cameras will take 1000 pictures over the duration of the flight
Balloon InterfacePayload attaches through strong center pipe that holds the whole
system together
Payload Design
Outward faced camera
Accelerometer
Heating resistors
Downward faced camera
Clamping tube
Top
Middle section
Base
Base
Balloon Interface Lock nut
PVC tubePayload top
Tether
Heating System
Heating Resistors
9 volt Batteries
Wiring Diagram for Resistor Heater
33 ohm resistors
9 volt
9 volt
9 volt
We will be using two Canon A570IS cameras to take pictures throughout the flight. The A570IS camera takes pictures at 7.1MP.
The cameras are currently both running a script via CHDK to take pictures at intervals of 10 seconds for the entire flight (4GB card, max 4mb/picture, estimated 3 hr flight).
The interval script has been tested and it is running fine.
Shutter speed will be adjusted to a fast setting via CHDK assuming there are no conflicts between doing this and running the interval script.
Further camera testing will be done between 3/26/2009 and 3/29/2009 to make sure a faster shutter speed and the interval script work. If they are not compatible a default shutter speed will be used.
Camera System
During our flight we will be recording the flight with a Hobo Pendant G 3-axis accelerometer.
The Hobo Pendant G can log 21,333 times when logging all three axis. To spread out logging throughout the 3 hour estimated flight we could log every 0.506 seconds. To error on the side of caution the Hobo will be set to log every 0.6 seconds.
The maximum G force rating on the Hobo is +/-3G. Unfortunately this may not be enough to record accurately on landing and if we were to have another launch we would look into other accelerometer options.
The temperature in the sat must be kept above -20C in order to stay within the Hobo’s operating range.
Accelerometer System
MK111 Timing Circuit
Structure and Thermal Properties
Polystyrene core0.023 W/m *K
5.7 oz 3k carbon fiber square weave
Carbon and coremate reinforcement
R
Tcondq
Lk
ri
ro
R**2
)ln(
wattscondq 13
Tin min= 0°C Tout = -60°C
Testing
Thermal testing in -50° F environment Thermal couples placed on the inside
and outside of payload.
Test vessel Test environment
Environmental test
-60
-40
-20
0
20
40
60
80
100
0 10 20 30 40 50 60 70 80 90 100 110
Time (10 min interval)
Tem
pera
ture
(D
eg
rees F
)
Inside Temp degrees F
Outside Temp degrees F
Test Results
Test failure point
Price/Mass ListPart Item Price
Carbon Fiber $ 90.00
Epoxy Resin $ 34.95
Hardener $ 17.05
Peel ply $ 7.50
Breather $ 5.20
Vacuum bag $ 6.45
CANON a570 Digital Camera$74.95x2= $ 149.96
HOBO Pendant G logger Kit $ 157.41
MK111 Timing Circuit $ 14.95
Polystyrene insulation $ 12.00
Gorilla Glue $ 12.54
9 volt batteries $ 13.54
9 volt holders $ 0.80
33 ohm resistors $0.39x3 $ 1.17
Perf board $ 4.49
Dry Ice 23 lbs $ 27.35
Thermal couples $ 32.01
Total $ 587.37
Funds still available $ 212.63
Component mass
Shell 700grams
Cameras 454 grams
Heater 215 grams
Accelerometer TBD
total 1369 grams
Price list
Mass list
Team Member Responsibilities
Daniel Koch-Exterior Structure, Composite Material handling and thermal properties
Jordan Gallegos-Structural design oversight handling
McMillan Misken-Payload construction Christopher Olson-Internal Heating assembly Cody Overcash-visual recording assembly and
accelerometer assembly Isaac Hamilton-Still Photo recording and wiring
assembly. Interior shell construction and assembly Thomas Mindenhall-Interior structural assembly
Upcoming Schedule
March 27th CDR March 28th - April 9th construct new
heater and retest Launch April 11th