design doc d.docx - cosgc homespacegrant.colorado.edu/cosgc_projects/space/fall_2012... · web...

40
Team Hang 7-Project Aether Colorado Space Grant Consortium GATEWAY TO SPACE FALL 2012 DESIGN DOCUMENT Team Hang Seven Written by: Abby Caballero, Nikhil Desai, Chase Goodman, Ethan Hollenbach, Becca Lidvall, Lucas Migliorini, Paul Smith, Sierra Williams 12/12/2012 Revision D Page 1

Upload: truongphuc

Post on 28-May-2018

220 views

Category:

Documents


0 download

TRANSCRIPT

Team Hang 7-Project Aether

Colorado Space Grant Consortium

GATEWAY TO SPACEFALL 2012

DESIGN DOCUMENT

Team Hang Seven

Written by:Abby Caballero, Nikhil Desai, Chase Goodman, Ethan Hollenbach, Becca Lidvall, Lucas Migliorini, Paul

Smith, Sierra Williams12/12/2012Revision D

Page 1

Team Hang 7-Project Aether

Revision Log

Revision Description Date

A/B Conceptual and Preliminary Design Review 10/20/2012

C Design Document C: Final Design Review 11/16/2012

D Design Document D: Final Design Profile 12/12/2012

Page 2

Team Hang 7-Project Aether

Table of Contents1.0 Mission Overview ..............................................................................................................4

1.1 Mission Statement..................................................................................................41.2 Mission Background..............................................................................................41.3 Mission Summary..................................................................................................4

2.0 Requirements Flow Down ..................................................................................................53.0 Design .................................................................................................................................6

3.1 Design Diagrams....................................................................................................83.2 Functional Block Diagram......................................................................................93.3 Schematic...............................................................................................................10

4.0 Management .......................................................................................................................104.1 Team Positions.......................................................................................................114.2 Schedule.................................................................................................................11

5.0 Budget ................................................................................................................................136.0 Test Plan and Results .........................................................................................................14

6.1 Testing Schedule....................................................................................................146.2 Structure Tests........................................................................................................146.3 Hardware Tests.......................................................................................................16

7.0 Expected Results ................................................................................................................197.1 Graphs....................................................................................................................20

8.0 Launch and Recovery..........................................................................................................228.1 Pre-Launch Plan.....................................................................................................228.2 Post-Launch............................................................................................................23

9.0 Results, Analysis, and Conclusions.....................................................................................239.1 Failures and Analysis..............................................................................................25

10.0 Ready for Flight.................................................................................................................2611.0 Conclusions and Lessons Learned.....................................................................................26

11.1 Conclusion............................................................................................................2611.2 Lessons Learned...................................................................................................27

12.0 Message to Next semester..................................................................................................2713.0 Special Thanks...................................................................................................................2814.0 References..........................................................................................................................28

Page 3

Team Hang 7-Project Aether

1.0 Mission Overview

1.1 Mission StatementThe mission for team ‘Hang Seven’ is to design, build, test, and launch a BalloonSat to 30

kilometers. The BalloonSat “Aether” will be outfitted with one working homemade Geiger counter and one off-the-shelf Geiger counter. The objective for this mission is to discover how well we can manufacture a Geiger counter and measure how gamma radiation increases in relation to altitude.

1.2 Mission BackgroundIn any manned mission, within the atmosphere or in space, human safety is of utmost

importance. Safety has always been a priority in aviation. The Federal Aviation Administration has implemented many regulations to preserve and ensure human safety while in flight. Regulations have been passed regarding communications, structure, and passenger restraints. Subsequently, radiation is a main concern due to the prolonged effects of exposure on the human body during aircraft transit. Considering such risks, materials would have to be employed to ensure the safety of any passengers. Consequently, as altitude increases so does exposure to radiation of all kinds (alpha, beta, gamma); on a typical passenger aircraft traveling approximately 12,000 meters, the amount of radiation exposure will be double that on the ground. As one increases in altitude, much of the Earth’s natural protective attributes such as cloud cover, atmosphere, and the ozone layer are dissipated. Radiation in itself can be a lethal force, only 35 rad (.35 gray) of absorption will cause serious health effects. Negative health effects include: nausea, vomiting, hair loss, loss of consciousness, cancer, and even death. Such negative health effects could be affecting millions of people who travel in aircraft. Even minimal exposure to radiation may result in damage to the human body.

To give a general idea of how much radiation we are supposed to be measuring, a typical amount of radiation that an average person would receive a year would be around 1mSv/yr (0.1µSv/h average).

1.3 Mission SummaryOur original mission was to measure the depletion effect that two materials, carbon fiber

and aluminum, have on blocking radiation levels. This proved to be problematic as we experienced many setbacks and problems while making our Geiger counters. To better fit our skills we created an alternative mission: we have chosen to develop one Geiger counter to measure the levels of Gamma radiation in the atmosphere. This is a change from making three and also removes the materials carbon fiber and aluminum from testing. Furthermore we will launch a kit Geiger counter from space grant alongside ours to record the actual radiation measurements. We will also modify the original designs we found online to better suit our requirements, specifically so it will record to an SD card rather than producing clicks. The data retrieved from these two devices will be compared to determine how efficient our Geiger counter measures radiation.

Page 4

Team Hang 7-Project Aether

2.0 Requirements Flow DownThe requirements for the Aether mission are presented below. The requirements are an

overview of what needs to be accomplished by our satellite. The level zero requirements are all derived from the mission statement. All subsequent requirements are either derived from the mission statement or the previous requirements.

Level Number Requirements Requirement Met? Derived From

0 1 Payload shall ascend to an altitude of 30 kilometers via balloon

Yes, the balloon reached an altitude of 30.3 km.

Mission Statement

0 2 Payload shall store and collect data from our sensors

Partial success, one SD card successfully collected data while the other SD was corrupted.

Mission Statement

0 3 The payload mass will not exceed 1.025kg

Yes, we had a final mass of 1.025 kg.

Mission Statement

0 4 The payload shall be ready for launch by 1 December, 2012

Yes, the payload was ready on time.

Mission Statement

0 5 The team and project shall obey all safety precautions

Yes, all safety precautions were met.

Mission Statement

Level Number Requirements Requirement Met? Derived From

1 1 The payload will be able to hold all electronics and sensors

Yes, the payload successfully held all electronics and sensors.

0-R2/0-R3

1 2 The internal temperature of the payload shall not drop below -10° celsius

Undetermined, the data was collected on the corrupted SD.

1-R2/1-R3

1 3 The payload shall contain a power source

Yes, the payload had a power source of eight 9V batteries.

0-R2/0-R3

1 4 The payload shall be constructed solely of foam core

Yes, the payload was created from foam core.

0-R1/0-R3

Page 5

Team Hang 7-Project Aether

1 5 The payload shall contain two working Geiger counters

Yes, both Geiger counters were on the payload and working properly.

0-R2/0-R3

1 6 Geiger counters will be shielded with different materials

Requirement not met due to change of mission.

0-R2/0-R3

1 7 An American flag will be attached to the BalloonSat

Yes, an American flag was attached to our BalloonSat.

0-R5

Level Number Requirements Requirement Met? Derived From

2 1 The payload shall contain a heater Yes, the payload did not contain a heater.

1-R2/1-R3

2 2 The Geiger counters will be connected to the Arduino microcontroller

Yes, the Geiger counters were connected to the Arduino microcontroller.

1-R5/1-R1

2 3 One Geiger counter will be used as a control for radiation measurement

Yes, a kit Geiger counter was used as a control for radiation measurement.

1-R5/1-R1

2 4 The structure will be sturdy enough to survive the ascent and descent

Yes, the structure survived the flight.

1-R3/1-R4

2 5 The Arduino microcontroller will be programmed to collect information

Yes, the microcontroller was properly programmed.

1-R5/1-R1

2 6 Arduino and carbon fiber tubes will each be used to shield one Geiger counter from radiation

Requirement not met due to change of mission.

1-R5/1-R1/1-R6

3.0 Design

StructureAether shall be made with foam core, in a hexagonal shape, in accordance with the

diagram. This shape was chosen due to the centripetal force that will keep the Balloon Sat equipment on the side of the satellite as it hurtles towards the earth. The design will protect the equipment from the whip effect as well. The whip effect is caused by the balloon bursting and the satellite hurtling back towards earth . The components of the satellite will be attached to the inside walls of the foam core design, using hot glue, velcro, duct tape, and electrical tape. To attach the BalloonSat to the balloon, the flight string will run through a plastic tube attached

Page 6

Team Hang 7-Project Aether

directly through the middle of the structure. This tube will be secured with two metal washers on the outside of the structure held together with hot glue, as well as a paperclip on the outside of each washer to ensure that the tube will stay in place. Half inch insulation will be glued to all the sides of the surrounding inside walls but will be altered to fit in all of the components. There will be several holes in the design to accommodate for a camera, four on/off switches, and three LED indicators, to show the equipment is working. Wires will be secured down with electrical tape. All parts of the satellites will be subjected to testing and modification accordance to the results of those tests.

Geiger CountersOriginally, our design included three homemade Geiger counters. The prototype

counters were built following a schematic found online using disposable camera flash units.3 When the initial board did not work out well, we obtained a breadboard example and schematic (below) for a new, more complicated breakout board that would allow the Geiger counters to function properly. One Geiger tube would be not covered by any material, another would be covered with an aluminum tube, and the last with a carbon fiber casing. This would allow us to determine which, if any, material blocks radiation the best. However, due to difficulties with the sensitivity and design of the homemade Geiger counters, we decided to fly one homemade Geiger counter and one “off-the-shelf” Geiger counter built with a kit from Space Grant. Both of these Geiger counters were uncovered.

Using interrupt coding in Arduino, the counts the Geigers detects will be recorded to a mircoSD card. Due to the Arduino Uno only having one usable port for the interrupt coding, we split the Geiger counters so there was one per Arduino.

ArduinosTwo Arduino Uno boards were used for our BalloonSat. Arduino One had the humidity

sensor, pressure sensor, internal temperature sensor (analog), accelerometer, and homemade Geiger counter and was connected to two 9V batteries. The sensors were all soldered to the SparkFun, SD card shield that was provided to us. The Geiger counter was attached by running wires along the sides of the payload. Arduino Two was connected to the external temperature sensor (analog) and the kit Geiger counter with three 9V batteries attached because the kit Geiger counter required an input of 9V versus the 5V needed for the homemade Geiger counter. Both items were connected to the Arduino through long wires that allowed them to be in the correct position for flight in the payload. Each Arduino was connected to an external switch and LED.

The design diagrams, pictures, and functional block diagrams are shown below.

3.1 Design Diagrams

Page 7

Team Hang 7-Project Aether

Measurements are in millimeters_

Page 8

Homemade Geiger Counter

Team Hang 7-Project Aether

3.2 Functional Block DiagramNote: Different colors signify the separate systems.

3.3 SchematicThis is the Geiger counter final design schematic. Parts are identified below:

Page 9

Heater (not shown)

Camera

Kit Geiger Counter

Batteries

Arduino

Team Hang 7-Project Aether

LM555: 555 timer2N2222: TransistorIRF640: Voltage RegulatorIN4007: Zener Diode

4.0 Management Work will be divided among the each of the team members. All members of the team will

lead/specialize in at least one of the subsystems (The lead position is in black, the assistant position is in white). The assistant position will entail checking and aiding the leads of the subsystem they are assigned to. Our schedule is made up of weekly meetings on Monday and Tuesday along with extra meetings for building, testing, and review preparation.

4.1 Team Positions

Page 10

Transformer Pins

Capacitor series for smoothing the circuit

Team Hang 7-Project Aether

4.2 Schedule

Date Meeting

09/13/2012 Team Meeting (8-10pm) (Weekly)

09/17/2012 Team Meeting (8-10pm) (Weekly)

09/18/2012 Team Meeting (8-10pm) (Design Complete)

09/24/2012 Create Proposal (8-10pm)

09/27/2012 Review Proposal Meeting (10-12am)

09/28/2012 Turn in Proposal (4pm)

10/02/2012 Presentations Due (7am)Conceptual Design Review (9:30-10:45pm)

Page 11

Team Hang 7-Project Aether

Team Meeting (8-10pm)

10/05/2012 Authority To Proceed (9am-3pm)

10/18/2012 Rev A/B and pCDR Presentation Due (7am)Pre-Critical Design Review (9:30-10:45am)

10/23/2012 Team Meeting (8-10pm)(Prototyping Design Complete)

10/28/2012 Drop and Kick Test (7-8pm)

10/30/2012 Whip Test (8-9pm)

11/05/2012 Team Meeting (8-10pm)(Final Testing Of Drop ,Whip, and Kick

Tests Complete and Confirmed )

11/06/2012 Team Meeting (8-10pm) (All Hardware Required)

11/11/2012 Hardware Tests (12-4pm)

11/12/2012 Team Meeting (7-10pm)

11/13/2012 DEMO – In Class Mission Simulation TestTeam Hours with Chris (5-8pm)

11/14/2012 Team Meeting (6-11pm)

11/15/2012 Cold and Power Tests (8-11pm)

11/16/2012 Rev C Design Document Due (12pm)

11/27/2012 Launch Readiness Review (9:30-10:45am)Team Meeting (8-10pm)

11/30/2012 Final BalloonSat Weigh-in (8am-1pm)

12/2/2012 BalloonSat Launch (6:50am)

12/11/2012 Final Presentation(6:45-9:00pm)

12/13/2012 Final Design Document Due

5.0 Budget

Page 12

Team Hang 7-Project Aether

Item Quantity Source Weight

Cost

Structure

Foam Core 1,596cm^2 Gateway 103g $0.00

Aluminum Tape 150cm Gateway 5g $0.00

Hot Glue 5g Gateway 5g $0.00

Insulation 1,000cm^2 Gateway 50g $0.00

Carbon Fiber Cap

3cm^2 Gateway 30g $5.00

Aluminum Cap 3cm^2 Gateway 35g $2.00

Hardware

Disposable Camera Flash Unit

6 MadScientist.com 50g $17.95

Geiger Tube 10 Ebay.com 300g $54.50

Geiger Parts (see above list)

21x3 CU Electronics Store/J.S.Saunders

30g $32.79

Copper Wire 3 m McGuckin’s 2g $2.00

Heater System 1 Gateway 100g $0.00

Plastic Tubing 1 Gateway 4g $0.00

Cannon SD780 1 Gateway 130g $0.00

Dry Ice 5kg Safeway N/A $12.00

Batteries 20 (including tests) Safeway 185g (flight

weight)

$30.00

Total 1025g $155.24

Page 13

Team Hang 7-Project Aether

6.0 Test Plan and Results

6.1 Testing Schedule Structure Tests

○ Drop Test (10/28)○ Kick Test (10/28)○ Whip Test (10/30)

Hardware Tests○ Geiger Counter Test Pt. 1 (11/7 & 11/9)○ Camera Hardware (11/13)○ Arduino Sensors (11/13)○ Power (11/15)○ Cold (11/15)○ Geiger Counter Test Pt. 2 (11/26)○ Geiger Counter Test Pt. 3 (11/30)

6.2 Structure Tests

Drop Test After completing the structure, we tested to see how well our structure would survive

landing by dropping it off of multiple buildings. These buildings included the front balcony of the ITLL and the top of the DLC. The drop off the ITLL building ended in failure, our box was unable to handle the impact of landing and broke open. In order to simulate the weight of the hardware we placed rocks inside of it that were approximately the same weight as the components will be for launch. Our structure was holding weight to simulate the hardware that will be inside it. We concluded that our structure was sufficient enough to withstand the impact of landing.

Kick Test

Page 14

Satellite

Team Hang 7-Project Aether

We tested our structure to see how well it would survive a rough landing. To do so, we kicked our structure down a huge flight of stairs in the DLC. The weights were weighed to ensure the correct amount of weight was placed inside our box. Upon kicking the structure down the stairs the box encountered many of the same force it could experience in a rough landing. After the test we examined our structure. No major damages were incurred from the testing. We concluded that our structure was able to withstand the battery it may encounter upon landing.

Whip Test Our final structure test was to ensure that our structure would stay intact during the

descent. During descent, the BalloonSat will possibly encounter high magnitude G-forces. The purpose of the whip test was to ensure that the structure would hold and not rip away from the rope. The whip test actually included us attaching the structure to a similar rope and violently swinging it back and forth repeatedly to replicate the whiplash conditions it will be exposed to. We swung it in a variety of directions to ensure its stability. We concluded that our structure was fully prepared to encounter the violent G-forces experienced during descent and landing.

6.3 Hardware Tests

Page 15

Team Hang 7-Project Aether

Camera HardwareWe tested our camera hardware by turning on the camera and running it for about an

hour. When the hour was up we pulled out the SD card and plugged it into a computer to see if it recorded the pictures. The code on the camera worked perfectly and we were able to obtain many pictures. This test was run more than once, with the latest time being two days before payload turn in for flight.

Arduino Sensors We tested our Arduino sensors and we have confirmed that the sensors work. The

sensors do in-fact detect changes in their relative measurements. We calibrated our sensors before launch, so the data that we get back from them is accurate.

Cold Our final test was the cold test. In this test we subjected the various sub- systems to extreme cold. This cold temperature was provided by two dry-ice blocks. Our BalloonSat was placed in between the blocks and set inside a cooler. In the cold test we only tested our Arduinos, camera, and heater because our Geiger counters were still not functional. The test was to last the duration of proposed flight time(approximately 2.5 hours). After the allotted time we removed our BalloonSat from the cooler. The satellite was very cold to the touch. We opened our box and soon discovered that our 9V batteries had died. This discovery was very disconcerting to us. However, the box was relatively warm inside, with our camera and heater being very warm to the touch. Even though the batteries died; we did find that the Arduino’s did retrieve data for about 45 minutes. According to the predicted flight time, the Arduino would have suffered the coldest temperatures during this 45 minutes. In conclusion, our systems could survive the extreme cold that would be experienced during flight. Geiger Counter Test Pt. 1

Page 16

Team Hang 7-Project Aether

By following the schematics and instructions online about hacking a flash unit of a disposable camera, we built circuits for the Geiger counters and soldered on the Geiger tubes bought from Russia. After completing the building, we brought 5 Geiger counters to a Physics Department Laboratory for testing. Art Klittnick was extremely helpful towards us, providing a source of radiation (thorium and uranium), power, and an oscilloscope to check if the Geiger counters were detecting radiation properly.

We connect one Geiger counter to 5V power and ground, and wired the output to an oscilloscope. The oscilloscope read the voltage spikes caused by radiation detection from the tube. However, the circuit was not well made because there was too much noise with the read out and we could not see spikes for more than a few seconds before the oscilloscope no longer showed any logical outputs. By testing the circuit with a Geiger tube that Mr. Klittnick had and knew functioned correctly from previous tests, we found that the circuit was not made well enough to use for radiation detection in our balloon satellite.

After this was determined, we needed a way to test the Geiger tubes separately. Mr. Klittnick assisted us again in this by providing us with the Geiger board he made previously. The board correctly detected a radiation source when it was brought close when connected to the tube that Mr. Klittnick owns. When we connected our Geiger tube bought from Russia, the tube did not record any spikes when the thorium radiation source was close. After looking closer at the specification of the tubes and other information online we discovered that the SI-3BG tubes (the ones bought from the Ukraine) were not very sensitive to radiation as they are meant to detect large doses not just background radiation. However, because of time and money constraints, we will not be able to replace the tubes with more sensitive ones before flight. We expect that our data will not be as clear with the less sensitive tubes, but that we will still get numbers that allow us to compare the uncovered Geiger with the two covered Geigers.

Geiger Counter Test Pt. 2After the initial testing with Mr. Klittnick, we decided we needed make new Geiger

counter circuit. Mr. Klittnick generously provided us with a breadboard circuit and a more sensitive Geiger tube for programming and testing purposes. We tested the board with an oscilloscope to make sure it detected radiation and worked from there to create our boards for flight and the code for the Arduino.

Utilizing the electronics store at CU and J.B.Saunders in Boulder, we acquired all the necessary parts to build our Geiger counter boards. By following the schematic and using the breadboard circuit as an example we soldered all the piece onto a perf board. However, after we completed the soldering and connected the power to test it, the board began to smoke. We discovered that we had put a few of the diodes backwards, but even after that was corrected, the boards still smoked and did not work. The piece smoking and overheating was the IRF640 voltage regulator. Double and triple checking the wiring of the circuit provided us with no results thus far. We are going to talk to Mr. Klittnick and Tim May as soon as possible for assistance in troubleshooting this problem.

Page 17

Team Hang 7-Project Aether

Despite our boards not function, we still attempted to work on the Arduino coding to collect data from the Geiger counters during flight. The breadboard Mr. Klittnick gave us was the best way to test this as we knew it detected radiation from the test with the oscilloscope. We also enlisted the help of an electrical and computer engineering, Alex Mault, as he knows Arduino programing and circuits extremely well. However even using his advice to try to write the code with interrupts to read the radiation the tube detected, we have not yet been successful in writing a code that will allow us to collect the data we need. To solve this, we are going to work more with Alex Mault and Alex Milewski to successfully write a code for the Geiger counters.

Geiger Counter Test Pt. 3Through the assistance of Tim May, we checked each of our connections and parts. We

double checked the voltage regulator and ended up buying new ones because we fried them when we ran the first tests. This troubleshooting managed to fix the problem we had so we were able to create three working circuits that, when connected to an oscilloscope, gave us spikes that were correct for the Geiger counters.

After the initial tests, we were not sure that we would be able to get enough radiation readings from the homemade Geiger counters due to the insensitive tubes. We were able to get data, but it showed no clear spikes when a source of uranium was brought in close proximity. For this reason, we decided to build a Geiger counter from a kit given to us from Space Grant. This kit would be used as a base to compare to our homemade Geiger counter to see if we could receive data that would be similar, even if it was weaker.

As for the programing of the Geiger counter, we were fortunate in getting help from Emily Logan and Dylan Herron who were working on the Arduino coding for the same Geiger kit we used. Dylan was extremely helpful with his advice on using interrupts and how that coding worked. Because there are only two pins on the Arduino Uno for interrupt coding and they only one seemed to work with our programing, we decided to put the Geiger counters on different Arduinos. The homemade counter was attached to the Arduino board with the humidity, pressure, internal temperature, and accelerometer sensors while the kit Geiger counter was attached to the board with the external temperature sensors.

Once the program was figured out, we ran a mission simulation with both Arduinos. The results for the Kit Geiger counter are graphed below. As is labeled, a decrease in radiation readings can be seen over time towards the end of the simulation. This is because the Geiger counter detects less radiation as the power provided to it decreases. The spikes in the graph are points when uranium was brought close to the counter. The data here is ground data, which the flight data can be compared to in order to better understand the readings we receive. Average radiation for this test was about 0.5 microSieverts.

Page 18

Team Hang 7-Project Aether

1 7 13 19 25 31 37 43 49 55 61 67 73 79 85 91 97 1030

0.5

1

1.5

2

2.5

3

3.5

4

Radiation(uSV) v. Time

microSv

Time (min)

micr

oSie

vert

s

Safety

To ensure that team members are not in any danger at any time during the building and testing stages of our balloon satellite, we are taking the necessary precautions to promote the safety of the team. When working on the project teammates must work in pairs or multiple members to make sure that there is always someone there to help if there are any problems or injuries. While working with dry ice, gloves are worn, sleeves are recommended, and a proper container is used to prevent any injuries to the team. During the testing all team members must stand at least 10 feet away from the payload while one member will cautiously perform the whip test, drop test, and stair test. Safety goggles are worn when dealing with soldering, dry ice, or any other dangerous materials.

7.0 Expected ResultsIn our Geiger counter experiment, we initially planned to have three homemade Geiger

counters, two with a different materials for protection. However, due to unexpected problems we modified our experiment to have two Geiger counters, one kit Geiger counter and one homemade Geiger counter, both are uncovered. Our goal is to test the levels of gamma radiation found in the upper levels of the atmosphere and in near space and to compare our homemade counter to a ‘real’ Geiger counter, the kit. We expect that the radiation will increase to lethal levels. On the surface of earth, the level of gamma radiation is about 0.05 microSv (microsSieverts) per hour. An extremely lethal level would be 10 Sv, which will cause incapacitation or death within seconds.4 We expect that the level will not reach this high, but could cause high amount of damage if exposed for a slightly longer amount of time. The homemade Geiger counter should have a lower reading of radiation due to a less sensitive Geiger tube.

Page 19

Uranium close

Decrease in Power

Team Hang 7-Project Aether

7.1 Graphs

We predict that radiation will increase linearly with time during the flight until balloon burst. The kit Geiger counter will be more sensitive to the radiation than the homemade Geiger counter.

Pressure should decrease with time (altitude) until balloon burst, as which point it will increase again as the balloon descends.

Page 20

Launch

Burst

Team Hang 7-Project Aether

Humidity should decrease initially, then increase until burst, and reverse that trend on the trip down.

External temperature should decrease until the start of the stratosphere, at which point it will increase until the balloon bursts. As the balloon falls, the temperature will initially decrease but then begin to rise as it travels through the troposphere on the way to the ground.

Page 21

Burst

Launch

Launch

Burst

Team Hang 7-Project Aether

The accelerometer should first read fairly consistent data, but then read very random data when the balloon bursts and the satellites are in free fall. Once the parachute is released and begins slowing down the payloads, they will reorient themselves and the data will become more consistent once again

8.0 Launch and Recovery

8.1 Pre-Launch PlanOn launch day our entire team will travel to Windsor, Colorado to launch our BalloonSat.

Before launch we will check that all LED indicator lights are on when each switch is flipped on and seal the balloon so it is completely prepared for launch. We will also verify that there are no structural irregularities or damages. Ethan will be responsible for launching the satellite and also flipping all switches to ‘on’ before throwing it into the air.

Three team members: Lucas Migliorini, Sierra Williams, Becca Lidvall, will make up the recovery team. They will drive to where the BalloonSat touches down to retrieve all hardware. Upon recovery they will check the external structure for damages and also the LED lights to see if any power remains. After the status of the entire external structure has been recorded they will open up two panels and perform similar observations on the inside. Before this they will turn all switches to the ‘off’ position. The first check will be to make sure all hardware is intact and in the secure place it was at launch. Secondly they will retrieve the SD cards from the arduino and safely store them for data retrieval later.

Page 22

Burst

Launch

Team Hang 7-Project Aether

8.2 Post-LaunchSeveral of the members of Team Hang Seven traveled to the launch and then ventured

out to recover the balloon. Lucas Migliorini, Sierra Williams, Becca Lidvall, Paul Smith, and Chase Goodman found rides out to the launch site in Windsor. The drive took approximately one hour and 10 minutes. At the site, the launch took place at 7:00 am. Upon launching our BalloonSat, Chris Koehler monitored the direction the balloon flies. The recovery team consisted of Lucas Migliorini, Sierra Williams, and Becca Lidvall.

Launch and recovery went very well. Lucas Migliorini, Sierra Williams, and Becca Lidvall ventured out to Nebraska to retrieve our satellite. The total drive time ended up around 10 hours, including refueling. Upon recovery, the satellite was intact. When the team opened the satellite, everything was still intact. They then brought the satellite back for data analysis.

9.0 Results, Analysis, and ConclusionDue to a failure with the Arduino and SD card, the humidity sensor, pressure sensor,

internal temperature sensor, accelerometer, and homemade Geiger counter produced very little data. When the data on the SD card was eventually recovered, we had no usable information from the sensors and accelerometer. However we did receive about seven minutes of data from the homemade Geiger counter.

The Arduino connected to the external temperature sensor and the kit Geiger counter did give us data. The graphs of this data are below.

Page 23

Launch

Rope Cut

Loss of Power

Team Hang 7-Project Aether

For our external temperature sensor, we used an analog sensor due to difficulties with digital sensor we initially planned to use. The trend of the graph is exactly what we expected, with a decrease in temperature until the end of the troposphere, at which point temperature began to increase. At balloon burst, the satellite began falling which caused a much more rapid decrease in temperature as it fell through the stratosphere and then an increase as it traveled through the troposphere toward the ground. However, we did experience a loss of data at two main points. The points are labeled on the graph. Due to these, we lost about five minutes of data for the first gap and about 20 minutes for the second gap. The trends in the graph are still visible though, as are the main events of the flight.

The graph below is the radiation versus time during our balloon flight for the kit Geiger counter. Again, we had a loss of data during the flight that caused a gap in our flight; the second loss of data that was found in the temperature graphs is at the point when the Geiger counter no longer gave us any data due to lack of enough power to it.

The radiation increased with altitude during most of the ascent of the flight. However, there was a leveling off in the radiation, and even a slight decrease. Due to a lack of accessible information, we are not sure if this was an expected decrease, or if the decrease was due to less power being available to the Geiger counter. Ground tests of the counter showed that as the batteries lost power, there was a decrease in the counts per minutes that the Geiger was outputting.

Page 24

Launch

Rope CutLoss of Power

Losing Power

Team Hang 7-Project Aether

The graph above is the data from the homemade Geiger counter. Due to the failure with the Arduino, we were only able to recover seven minutes of usable information. However, the trend with varying increase and decrease in radiation reading makes an estimate 30 to 50 minutes after launch, according to graph of the kit Geiger counter, feasible. The difference in sensitivity of the Geiger tubes can be clearly seen from this. During 30-50 minutes after launch, the Kit counter was getting readings of around 8 microSieverts. The less sensitive homemade counters only showed a reading of 2 microSieverts in this time period. This proved our hypothesis correct that we would be able to get data from the homemade Geiger counter, but that it would be less sensitive.

9.1 Failures & AnalysisProject Aether had two major failures: the camera and one of the Arduinos

malfunctioned. The camera did not store or even take pictures during flight because of faulty programing. In order to confirm this failure a test with the camera with the same SD card was implemented and congruent results were found. Then a test using the camera and the SD card from team 4 was performed and everything worked. So in order to fix the problem, the files on the malfunctioning SD card were rewritten using Team 4’s SD files, and this fixed the problem completely.

Our second critical mission failure was that the SD card for the first Arduino became corrupted during flight. This Arduino housed all the required internal sensors along with the homemade Geiger counter. The SD card for this Arduino was deemed unreadable by our computers. Even though this SD card was corrupted, Alex Mault, an undergraduate electrical and computer engineering student, was able to recover some of the files. Afterwards a test was

Page 25

Team Hang 7-Project Aether

done using a new SD card and this time the Arduino worked. It was discovered that both the homemade Geiger counter and the sensors were unable to run at the same time, because there was faulty programming and not enough power provided to the Arduino. The combination of the error in the programming and lack of power caused the Arduino to reset. A very rare occurrence made the board attempt to initialize at the same time that it was writing to the card, which corrupted it. There is no way to fix the original SD card and even the data recovered on it was mostly inconclusive.

10.0 Ready for FlightTo prepare for future flights, our team fixed the camera, geiger counters, and the arduino

with environmental sensors. Since the camera did not take any pictures in the first flight, we examined the code given to us by the Gateway to Space class, and found it to be corrupted. Therefore, we took the original code, and re-uploaded that into the camera, fixing the bugs our previous code presented. When retrieving the satellite we took care to not damage the structural integrity of the box when collecting our flight data. Our box suffered no severe deformations and only one minor dent from the actual flight, which is non-fatal to a reflight mission. We would need new batteries and a new SD card, however, and the software and hardware would be ready to fly again. We would recommend another round of testing if the payload was to actually fly again, as, like any big project, we cannot be completely be certain every flight bug was fixed. This test would include making sure all of the sensors can read and record data at the same time, as well as verifying the accuracy of these tests, as we have already done. For a reflight, after replacing the SD cards and batteries, one must turn on the four switches on the outside of the box, and double check that all the indicator lights are on..

11.0 Conclusions and Lessons Learned

11.1 ConclusionFrom the data we were able to recover after the launch we found that the homemade

Geiger counter we constructed was not to the same caliber as the Geiger kit we were given. It was less sensitive to radiation levels then the kit Geiger was, because the exposure was not as high as what the homemade Geiger counter could detect. The difference between the two counters was that the Ukraine tubes that we used are only made to detect high levels of radiation like exposure from a nuke.

In addition to the data we got from the correlation of the two Geiger counters we were able to confirm that radiation is directly correlated to altitude. As our payload increased in altitude, the levels of radiation we became exposed to also increased. this is due to the thinning of atmosphere as you get higher up and therefore allowing more radiation to pass through without being scattered or reflected.

From our data analysis, we were able to conclude the reasons for our main failures. The failure of one of our Arduinos was due to a corrupted SD card which was supposed to record temperature, pressure, and humidity, as well as recording our homemade Geiger counter data.

Page 26

Team Hang 7-Project Aether

Another major failure was our camera which did not take any pictures. We found that this was due to faulty programming of the SD card, and was fixed by re-entering the correct programming in place of the corrupt program to find that the camera ran smoothly again as it did before launch.

As a team, we came to a conclusion that our mission was “somewhat” successful meaning that even though there were some major errors and failures in the mission, we got the data that we needed to confirm that two out of our three experiments were a success.

11.2 Lessons LearnedOver the course of the year, we have learned many things that we could have done better

in order to make things go smoothly. To begin with, making our team meetings more efficient would be the number one thing that would have made the semester less stressful. If we stayed organized and knew exactly what was going to occur at our team meetings, they would have gone by much faster. This leads to the mistake of making our schedule too simple. When we created our schedule, we just had a schedule with just dates when we were going to meet. If we were to make out schedule more elaborate and actually include what should have been accomplished in those meetings, then we would have saved many hours in the ITLL not working on anything.

Another major thing we could improve is the way we tested our sensors and Geiger counters. We did minimal testing on these sensors and Geiger counters just to make sure they were working. If we tested these sensors and Geiger counters more and made sure they were working perfectly, then our project would have gone much smoother. To make us better prepared for building the Geiger counters, we should have done further research on how the technology works, so we would have had a better understanding and a better idea of how to construct them.

12.0 Message to Next semesterA semester of Gateway to Space may be overwhelming, frustrating, and time consuming

to say the least, but is by far one of the best classes you will ever have. Some advice to help you have an easier semester is to be sure to use your time efficiently, and do not rush the testing process. The biggest factor of our failures was not testing over and over to ensure that all our subsystems worked properly. The easiest way to motivate you to work over 25 hours a week on this project is to get to know your teammates and have a good relationship with all of them. This will make it a lot easier and fun when having to meet every night. Above anything, be sure to make the most of your experience and never give up even if you do not succeed. Think about all that you will achieve with this project, and the fact that few people have the same opportunities to do something like this. This is a once in a lifetime project so work harder than you ever have before because in the end it will all pay off. 13.0 Special ThanksTeam Hang 7 would like to give a special thanks to a few invaluable people. Without their help, our satellite never could have been completed successfully and on time. We appreciate them greatly!

Page 27

Team Hang 7-Project Aether

Chris Koehler (and Space Grant) Tim May Art Klittnick (and the Physics Department) Alex Mault Dylan Herron Emily Logan

14.0 References1 "Appendix C/Materials Used in Aircraft." Federal Aviation Administration

Fire Safety. Federal Aviation Administration, n.d. Web. 28 Sept. 2012. <http://www.fire.tc.faa.gov/pdf/handbook/00-12_apC.pdf>.

2 "Radiation Hazard at Aircraft Altitudes." Radiation Hazard at Aircraft Altitudes. N.p., n.d. Web. 28 Sept. 2012. <http://www.swpc.noaa.gov/info/RadHaz.html>.3 "Step by Step Hacking a Disposable Camera Flash Unit to Power a Geiger Tube." « Mad

Scientist Hut Blog. N.p., n.d. Web. 21 Oct. 2012.<http://madscientisthut.com/wordpress/daily-blog/hacking-a-disposable-camera-flash-unit-to-power-a-geiger-tube/>.

4"Lethal Levels of Radiation Recorded in Fukushima Gamma Ray Image." PhotoBlog. N.p., n.d. Web. 21 Oct. 2012. <http://photoblog.nbcnews.com/_news/2011/08/02/7227954-lethal-levels-of-radiation-recorded-in-fukushima-gamma-ray-image?lite>.

Page 28