follow up design review the university of northern colorado gogreensat jessica gage, max woods,...
TRANSCRIPT
Follow up Design Review
The University of Northern Colorado
GoGreenSAT
Jessica Gage, Max Woods, Brent Hill, Ryan Marshall, Zach Sears
Mar. 27 2009
IndexSection Slide NumberMission Overview 3Mission Requirements 4Fundimental Block Diagram 5Concept of Operations 6Structual Drawings 7Structual Drawings 8Structure** 9Schematic* 10Parts List* 11Subsystem Overview* 12Subsystems-Peltier Cooler** 13Subsystems-Pendulum** 14Test Plans 15Cold Test Results** 16Cold Test Results** 17Cold Test Results** 18Management 19Conclusion 20Appendix A-Calculations: Impact Test** 21Appendix B-Weight Breakdown** 22Appendix C-Box Dimensions** 23
*Change from original CDR, **New since original CDR
Mission Overview The goal of GoGreen SAT is to observe the
most effective materials and conditions in which a payload can generate energy to be used and stored.
GoGreen SAT will determine the maximum energy output of different onboard systems throughout the flight.
The three energy systems are: Pendulum: Capturing the swinging motion of
the flight line Solar Power: Capturing energy from the sun Peltier Cooler: Using the differences in
temperature inside and outside the box to produce energy
Mission Requirements
Green: Compliant, Yellow: Partially Compliant, Red: Not Compliant
Requirement Method Status
The payload must not exceed a weight of 1.5 kg. Design, Test
The flight line should go through the payload's center of gravity. Design, Analysis
The payload must be able to survive an impact of at least 16m/s. Design, Test, Analysis
Components in payload must be able to survive a temperture of -80˚C. Design, Test
Payload must not "cut" through the flight line. Design, Test
Payload must survive the "shaking" of balloon burst. Design, Test
Fundamental Block Diagram
Concept of Operations
Before the launch of the balloon, the payload will be activated via an external switch to provide power to the Logmatic recording software.
During the ascent, the software will gather current readings from the solar panels, the Peltier cooler, and the pendulum system. At a rate of 100 data points per second.
The solar cells will gather light energy from the sun depending on the payload’s orientation (an increase in altitude is expected to produce an increase in energy output).
The Peltier cooler will produce a current as the outside of the payload is cooled by decreasing atmospheric temperatures, and the inside of the payload maintains a reasonably warmer climate.
The pendulum system is expected to produce a current as the turbulence of the payload causes the pendulum to swing the attached magnet over a series of six copper coils.
After payload recovery the SD card will be taken out of the data logger and the flight data will be dumped into excel. The data will be calibrated.
Structural Drawings
Copper Coils on Board
Side View of Box, Solar Panels on Top
Pendulum
Structural Drawings
Battery
Hobo, Barometer
Logomatic Hot Hands
Peltier Cooler
Copper Plate
Pendulum
Copper Coil
Back View of Box
Top View of Box
Side View of Box
Structure The box will be made out of ½ inch foam
core board which will be cut to the correct dimensions.
The box will be held together with hot glue.
The box will be reinforced with additional foam core board inside.
The outside of the box will be painted black to help absorb the heat from the sun.
PVC pipe will run through the middle of the box for the flight line to go through.
The pipe will be attached to the box using ball bearings.
Schematic
StartSw
Barometer
CurrentSensor
CurrentSensor
CurrentSensor
PeltierCooler
SolarPa2
SolarPa1
D1DIODE
L6100 coils
L5100 coils
L4100 coils
L3100 coils
L2100 coils
L1100 coils
87654321
CP1CP2
DataSeq
Logomat
+ V17V
*There will be resistors added to pull the created power
*The grounds will go to the ground on the Logomatic
Parts List
Parts Company Model
Solar Panels Flex Solar Cells, OEM Components RC 7.2-75
Peltier Cooler Frozen CPU 437W
Magnet K&J Magnetics, Inc. DX0X0-N52
Low Current Sensor Sparkfun Electronics ACS712
SD Card
Logomatic Sparkfun Electronics V1.0
Ball Bearings McMaster-Carr 57155K356
Copper Sheet Whimsie 21-gauge
Foam Core Board Hobby Lobby 1/2"
Lithium Battery 7V
Subsystem Overview Power for the payload will come from a 7V
battery. Data from the flight will be stored at a rate
of 100 points per seconds in a SD card. The payload will have two states, non-
active and active. A protected switch will be installed on the outside of the box to activate the payload.
Peltier Cooler-there must be a temperature difference between the two plates.
The inner components (Hobo, battery, logomatic, and SD card) should not get below negative 20˚C.
Pendulum-Must swing in only one dimension.
Subsystems-Peltier Cooler
Peltier Cooler- If you apply a voltage to a thermocouple it causes a temperature difference between the two plates.
The Seebeck Effect- If two different metals are connected at two different locations and there is a temperature difference between the two junctions a voltage will be created.
The peltier cooler will be used to create the Seebeck effect and produce a voltage by creating a temperature difference between the plates.
The peltier cooler will be integrated into the box so one side faces out of the box and the other inside.
There will be a copper sheet on the outside of the box to cool that face of the peltier cooler more efficiently.
Hot Hands will be used to heat the other side of the peltier more efficiently inside the box.
*http://www.heatsink-guide.com/peltier.htm
Subsystems-Pendulum
The pendulum system will use magnetic induction to create power.
A magnet will be placed on the end of the pendulum.
The pendulum will swing back and forth over six copper coils.
The swinging motion of the balloon flight line will drive the pendulum.
Test Plans
Cold Test- Dry Ice/Liquid Nitrogen, Styrofoam cooler, four thermo probes, four multimeters, timer
Impact Test- high place to drop box from
Shake Test- Line/string Time Test- Timer Flight Simulation Test- Time and Cold
test combined with all components running/storing data
Cold Test Results
Cold Test #1 and #2: The box was suspendered inside a cooler where dry ice was placed. This test was done to see how well a box inside the main box would insulate the electrical components. The dry ice did not cool the box enough and an additional test had to be run.
Cold Test Results
Cold Test 3: The box was suspended inside a cooler with liquid nitrogen in the bottom of it . The liquid nitrogen cooled the box past the predicted low temperature of the flight. Another test will be run at a later date when all of the components are working.
Cold Test Results
Peltier Cooler Cold Test #1: This test was run during cold test #3. The results from this test showed that there needed to be a way to stop the peltier cooler from pulling voltage from the system.
Impact Test Results A test box was constructed of the same size and relatively
the same weight as the flight box to use for the impact test. This was done as to not damage any actual flight components
before flight. During actual flight impact the two pieces that need to
survive are the Logomatic and SD card. The test box was dropped of a stair well at different heights. The impact speed from past flights was calculated to be
between 10mph-35mph (4.5m/s-15.5m/s).
Flight of Stairs Impact speed(m/s) Damage done to Box
1 7.7 none
2 10.8 none
3 13.3 slight dent
4 15.3 slight dent
5 17.1 slight dent
Management
Program Manager-Jessica Project Members-Max, Brent, Ryan,
Zach Faculty- Dr. Bob Walch
Meetings, Tue. 6:00 p.m. and Thus. 7:00 p.m. and scheduled as needed
Budget-$800-$900
Conclusion
Issues/Concerns: The magnet used in the pendulum system will
interfere with other components in the box. The current produced by the pendulum system
will be to little to measure at times. The temperature difference between the two
plates of the peltier cooler will “flip-flop” during the descent, which will pull energy instead of produce it. This problem could solved with a diode.
The box will continue to swing in one direction for extended amounts of time, causing the pendulum not to move much.
This data from this payload should allow the efficiency of each system to be analyzed during the different sections of the flight.
Appendix ACalculations: Impact Test
vf^2=vi^2+2ghvf=sqrt(vi^2+2gh)
vf=2gh
vi=initial velocity=0 m/s g=9.79m/s
vf=impact speedh=drop height
Appendix BWeight Breakdown
Item Weight (kg)Center Rod .019 Peltier Cooler 0.056Copper Sheet 0.3Box Frame 0.315Magnet 0.096Coils and Base 0.217Pendulum 0.03Solar Cells 0.012Batteries 0.12Inner Box 0.086Ball Bearings Hot Hand Pack Bearings for Rod Total Payload Weight 1.165
*Estimated Total Weight=1.4kg
Appendix CBox Dimensions
14”
7”
7”
7”
14”
20.5”
20.5” 20.5”
10.6”