HASP Student Payload Application for 2017

Payload Title:

The Greenhouse, Ozone and Atmospheric Trace gas (GOAT)

Payload Class: (check one)

X Small o Large

Institution: Durham Technical

Community College, North Carolina

Central University, University of North

Carolina-Chapel Hill and North Carolina

State University

Submit Date: 12/16/16

Project Abstract: Sulfur dioxide (SO2) is a gas that is found in the atmosphere at varying levels

depending on geography, season, and other climatological variables. Volcanoes naturally contribute to

worldwide SO2 levels but 99% of atmospheric SO2 is anthropogenic. Ambient sulfur dioxide needs to be

accurately monitored as it leads to acid rain, ecosystem destruction, and climate change. The

Greenhouse, Ozone and Atmospheric Trace gas (GOAT) project would compare and contrast the

results of discrete SO2 collection methods. GOAT will fly on a balloon-borne platform with a calibrated

SPEC Arduino Analog Sensor Module for SO2, a pair of Ogawa passive samplers, and microbial

cultures of Saccharomyces cerevisiae and Lactobacillus in order to evaluate their usefulness for

measuring the presence of upper atmospheric SO2. Temperature, pressure, and humidity data will be

collected in order to maintain the integrity of the data and inform the environment for controls in the lab.

Post-flight data will be analyzed in the atmospheric laboratory at North Carolina Central University. The

results recorded during GOAT’s flight will add to the scientific understanding of SO2 levels in the upper

atmosphere as well as identify best practices for future balloon-borne atmospheric collection

experiments.

Team Name:

The Unacceptable Risks

Team or Project Website:

http://www.theunacceptablerisks.com

Student Team Leader Contact Information: Faculty Advisor Contact Information:

Name: James Acevedo Julie Hoover

Department: Physics Science

Mailing Address: 200 W. Poplar Ave # 1637 Lawson St

City/State/Zip: Carrboro, NC 27510 Durham, NC 27703

e-mail: jaceved1@eagles.nccu.edu hooverj@durhamtech.edu

Office telephone: 919-535-7223 x8021

Cell: 240-350-1084 919-244-5968

FAX: 919-536-7289

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Introduction

Our student team The Unacceptable Risks (tUR) are all alumni of or currently attending Durham

Technical Community College. The Greenhouse, Ozone and Atmospheric Trace gas (GOAT) project would

compare and contrast the results of three discrete SO2 collection methods. Atmosphere will be recorded over

the course of about 15 hours in the upper atmosphere at around 37,000 meters. GOAT will use a calibrated

electronic Arduino SO2 sensor, a pair of Ogawa passive samplers, and microbial cultures of Saccharomyces

cerevisiae and Lactobacillus in order to measure the presence of atmospheric SO2. Temperature, pressure,

and humidity data will also be collected. This payload was chosen because it plays to the strengths and

interests of the team and showcases the high altitude ballooning skills that we developed during tUR-1, tUR-

2, and the NASA PIPER mission.

Fig. 1: Tentative mission patch for GOAT.

Overview: SO2

Sulfur Dioxide is a toxic gas that exists within small concentrations in the Earth’s atmosphere at about

1 ppb. It is an invisible, thick pollutant that is known for its signature “burnt match” odor. Of all the sulfur

compounds present in the atmosphere, SO2 is of utmost concern due to its high concentration and reactive

potential. SO2 readily reacts with water generating sulfurous acid and sulfuric acid aerosols. SO2 is found in

plumes around the source of creation that rise higher into the atmosphere. SO2 molecules are predominantly

found in the troposphere where they remain for a few days before they form condensation nuclei for aerosols,

clouds and acid rain. The residence time of SO2 in the stratosphere is over a period of week; this can cause

its impacts to have global rather than local effects as the layer gradually expands across the globe due to

fluctuations in wind patterns. These aerosols can cause a cooling effect globally since they reflect and absorb

sunlight which reduces the amount of incoming solar radiation that reaches the Earth’s surface. This happened

in 1993 when Mount Pinatubo erupted and launched 20 metric tons of SO2 into the lower stratosphere. A layer

of sulfur aerosols was still present in the stratosphere in 1995 from this event.

Sources of Atmospheric SO2

SO2 is released into the atmosphere naturally through volcanic eruptions, but this accounts for only a

small percent of all released SO2. Approximately 99% of SO2 in the atmosphere is anthropogenic and it is

released into the atmosphere through industrial practices such as coal burning for energy, diesel combustion

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from cars, and even through acts of war, as seen with the Al-Mishraq mine fire in 2004 and October 2016.

Burning sulfur-laden fossil fuels (coal, oil, and natural gas) to generate electricity is the major cause of SO2

pollution and two thirds of the SO2 emitted in the atmosphere comes from electric power generators. Coal-

burning electric power plants produce more than 12 million metric tons of SO2 per year globally. In the United

States alone, there were 3,570,841 metric tons of SO2 emitted from fuel combustion in 2014. Other smaller

sources include vehicles, locomotives, heavy equipment, manufacturing, oil refineries, and industrial

facilities. Vehicles that use diesel are of particular concern in certain geographic areas because diesel fuel

can form SO2, sulfate, and particulate matter (PM) during combustion. In most developed countries, the sulfur

levels from diesel fuel are below 50 ppm, but in developing countries it can be much higher. Many Latin

American countries, the Caribbean, Russia, and Africa have levels between 50 to 500 ppm or higher. Sulfur

mines also account for adding large amounts of sulfur in the air.

Environmental Impacts

Sulfur dioxide has negative effects on the biosphere, hydrosphere, lithosphere and atmosphere.

Aerosols that contain sulfuric acid can also contribute to acid rain which damages forests and their soil, bodies

of water, organisms, and ecosystems by increasing their acidity and decreasing their amounts of nutrients.

Many trees and plants are left vulnerable from the effects of acid rain which can lower their tolerance for

cold temperatures, insects, and disease. The detrimental impact to beneficial organisms in the soil is also a

significant concern. Beneficial minerals including calcium and magnesium can be stripped from the soil and

bound aluminum ions can be freed in the soil due to infiltration of acid rain. This mineral imbalance can inhibit

the ability of trees to absorb water from the soil and stunt the growth of plants. Marine organisms are also

affected; many aquatic animals are in danger due to an increase in acidity in the water and the contamination

of these pollutants. These pollutants can also move up the food chain in interconnected ecosystems with a

detrimental effect on birds that eat fish living in acidic conditions.

Public Health

The health effects of SO2 in the atmosphere can cause severe complications to the respiratory tract,

eyes, and skin. In a fire at the Al-Mishraq sulfur plant on October 22, 2016, at least two civilians were killed

from the high exposure of SO2 released and over a hundred-people needed medical attention. SO2 itself can

be a respiratory threat at high concentrations; It is considered immediately dangerous for life at 100 ppm.

The Environmental Protection Agency has set a national standard of 0.075 ppm over a one-hour period. Many

people who live or work near a power plant are exposed to higher levels of SO2. Children, the elderly, and

people with lung disease, asthma, chronic obstructive pulmonary disease, or bronchitis are most susceptible

to these issues.

At low concentrations (levels between 1 to 0.075 ppm) human health is still affected and the

respiratory defense systems are impaired at these levels. There is evidence in animals that shows inflammation

and damage to the lungs as well as a decrease in respiration. SO2 can mix with other compounds in the air and

combine to create sulfur oxides and particulate matter. Particulate matter is measured by its size; two

important types of particulate matter are PM10 and PM2.5. PM2.5 is more dangerous because it is two and a

half micrometers or smaller; particles of this size are easily inhaled and can enter the bloodstream through

the lungs. PM also can cause poor atmospheric visibility; creating a haziness in the air which can reduce sight.

This is mainly a problem in highly polluted areas, mostly urban areas.

Historical Perspective

Exploration of atmospheric composition is more crucial today than it’s ever been. With the threat of

climate change growing ever more serious with each passing day, it is crucial that we continue to study the

chemicals that nature and we as humans continue to release into the atmosphere. Thankfully, over the past

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ten years we’ve seen dramatic decreases in the release of SO2 into the atmosphere thanks to better technology

and stricter regulations. It is important to note that these declines could have never occurred without the

constant research being done by climate scientists all over the world. The progress in SO2 reduction is a key

example of how important the science of ozone and atmospheric detection is, and how it can be a huge factor

in preserving the environment and bettering human life.

NASA Methodologies & Background

There are many different ways that scientists today study and record data on SO2. One of the most

common ways is by satellite imagery and infrared technology. A few of the instruments that we researched

are the Total Ozone Mapping Spectrometer (TOMS), Ozone Monitoring Instrument (OMI) on NASA's EOS-Aura

satellite, the Atmospheric Infrared Sounder (AIRS), and the Moderate Resolution Imaging Spectroradiometer

(MODIS) on NASA’s Terra and Aqua satellites. These tools, while useful, are not accessible to most researchers.

This is why GOAT will focus on validating the data from lower cost alternatives.

GOAT will fly over New Mexico. From 2001-2015 the EPA has monitored ambient air quality trends by

compiling SO2 data from nine different monitoring sites across Arizona, Colorado, New Mexico, and Utah. The

average trend of concentrations across all nine sites ranged from a low of 45.77 ppb to a high of 89.14 ppb;

however, the individual monitoring sites vary greatly, with one site registering a local concentration high of

353 ppb in 2012. We expect our data to fall within the Southwestern US averages shown in Figure 2:

Year Mean ppb

2001 89.14

2002 76.29

2003 79.44

2004 74.59

2005 71.62

2006 67.77

2007 77.11

2008 60.40

2009 65.14

2010 62.27

2011 45.77

2012 65.33

2013 58.44

2014 54.22

2015 57.77

Fig. 2: Southwest Trends in SO2 Concentrations in 2001-2015 (epa.gov)

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Methodology for the Arduino Ultra-Low Power Analog Sensor Module for SO2 by SPEC Sensors

GOAT will be deploying electrochemical sensor modules into the upper atmosphere to discover the

sampling capacity of affordable atmospheric pollutant sensors. The ambient air sensors, with on-board

temperature recording, will be fitted to an Arduino microcontroller and paired with a microprocessor for

interpretation and logging of the data collected. The sensor for SO2 samples the air through a capillary

diffusion barrier which draws in the target gas to react with a catalytic metal selected for reactivity with the

target gas, which is surrounded by an electrolyte liquid. The catalytic metal acts as the sensing electrode,

sensing the electrons created or consumed by reaction with the target gas. Another electrode completes the

circuit. There is a linear relationship between the concentration of the target gas and the current passing

through the sensing electrode. As long as the sensors receive continuous power and remain in nominal

conditions, they can consistently detect 0-20 ppm of the target gas at a resolution of 0.15ppm, delivering

readings 15-30 seconds apart. Ambient conditions can affect the readings of the sensors but they operate

with no issues from -40°C to 50°C. Temperature extremes will affect reduced sensitivity in the sensors in a

linear fashion, which can be fairly easily and accurately reconciled when post-processing the data using the

values provided by the manufacturer and the onboard temperature sensors. The microcontroller delivers

power as it is needed and directs the data produced to the microprocessor where it can be converted to usable

values and stored.

After the sensors have been receiving continuous power, diligently working and reading gas

concentrations, peaks and irregularities will level and the highest level of accuracy of readings will occur

under nominal ambient conditions. As tested by the manufacturer, the sensors may have a 10-year life span

under regular conditions. They do rely on a few fairly delicate components and care must be taken with them.

They cannot sense if the capillary diffusion barrier becomes blocked with particulate, oil, or moisture. To

prevent this, we will ensure to always handle the sensor while wearing gloves, and our design includes a PTFE

membrane to keep out particulate matter. The sensors will function in a wide range of humidity levels, will

be protected from direct content from condensation by the PTFE membrane. Because the sensors function

continuously, in order to render useful and accurate data, they must be protected from too much variance in

pressure and temperature. Temperature protection will be discussed in the thermal control plan below. They

need to be protected in a housing material of a type that does not greatly react with the target gases; we will

be using ABS plastic for our 3D-printed parts. It is recommended that the opening through which air is brought

into the housing be protected with a permeable barrier, and the pressure regulated and moved across the

functional surface of the sensors in an even and controlled flow, lest there be irresolvable spikes in the data.

We will be operating out of these recommended parameters, but are confident in our ability to post-process

or otherwise account for the non-optimal conditions.

The sensors are affordable, small, and light. They could however, be fragile, containing thin electrodes

and electrolyte fluid. They will be powered up and subjected to a “bump” test prior to flight. A “bump test”

is when a known concentration of a chemical is purposefully released to the sensor in order to provide a

baseline reading. Prior to tUR-3, a Spring 2017 dress rehearsal, the sensors will also be subjected to a cryo-

vacuum test during which their functionality will be tested in simulated near-space atmosphere at

temperatures down to -60°C. They should deliver consistent linear data if conditions can be managed and

extremes avoided. The sensors are calibrated by the manufacturer under standard conditions of about 23°C,

50% relative humidity (RH), and 100 kPa. They are calibrated for 0 target gas concentration and mid-range

concentration with an air velocity of 0.01-0.05 m/s across the sensors. Accuracy will be greatest under these

circumstances. The sensors are fluid filled, but are specified to -30°C for intermittent use. Judging from the

temperature readings made by the previous balloon flights, tUR-1 and tUR-2, we can expect temperatures in

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the upper atmosphere to get down to -40°C and colder. The housing will be insulated to mitigate the

temperature extremes inside GOAT, and if the sensors continue to deliver readings, we may be able to post-

process the effects of temperature on the data.

The electrochemical gas sensors will be mounted and powered up by tUR and placed in their housing

for at least 3 hours prior to balloon launch with the accompanying Arduino and microprocessor pre-

programmed to adjust the readings for the ambient temperature as measured by the temperature sensor

accompanying the target gas sensor. The hull will maintain a fairly steady pressure and stream of air across

the sensor surface. Temperature will have effects on the reaction of the target gas with the sensor’s catalyst

metal but the microprocessor, using the manufacturer’s data, will reconcile the readings made by the sensors.

The sensor will be making continuous readings throughout the flight and the hours preceding it. As long as the

memory that the data is written to can be recovered intact, even a severe impact which damages the sensors

will not compromise the mission of the flight. We have tested the fortitude of our Arduino through drop testing

and a non-optimal landing from tUR-2 and have confidence in our ability to retrieve the data. We will be able

to log the corrected readings of the sensors against the time, altitude, temp, and pressure during the flight.

Methodology for the Ogawa Passive Sampler

GOAT will be testing an Ogawa passive sampler to evaluate its performance in the upper atmosphere.

Ogawa passive samplers are ambient air collection devices that use a coated pad to measure concentrations

of volatiles such as SO2, Cl, and O3 without relying on an external power source. The stable cellulose fiber

pads are 14.5 mm in diameter and about 1 mm thick. The sampler is housed in a plastic shelter for most

environmental collection needs but can be contained in a variety of non-reactive housings. The standard

shelter for the SO2 pads is 63.5 mm in diameter and 76.2 mm tall and only requires one pad to be effective.

GOAT will fly redundant pads to increase the chances of a successful collection. The pad is coated with

triethanolamine ((HOCH2CH2)3N) as an absorption reagent and requires ion chromatography techniques for

evaluation once the samplers are recovered.

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Fig. 3: A CAD mockup of the Ogawa jar/lid (B/A), perforated ABS printed inserts (C), and two of the three Ogawa sampler canisters (D), each containing two sampler pads (E). Silica gel desiccant not pictured.

The containers and pads are inexpensive, which make them a good choice for long-term monitoring

programs. The Ogawa sampler was recommended to us by Dr. J. J. Bang at the NCCU atmospheric lab because

he has used them repeatedly for his research with great success. It is also used extensively by the US National

Park Service, the Harvard School of Public Health, and the EPA.

The sampler is designed so that two pads can be stored in the same housing as long as both pads have

free access to the aeolian kinetic. The air flow is facilitated by stacking the pads with a proprietary washer,

stainless steel screens, and a diffusion barrier. This prevents the pad from being flush with the container and

allows the air to circulate freely and wash over the pad evenly while the housing protects the pad from

moisture and airborne debris. The sampler is created to be exposed to the elements and will be well-protected

within the hull of our payload. The lowest detectable range for SO2 is 3.8 ppb in a day. We expect to see at

least 1000 ppb.

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Fig 4: Ogawa passive sampler pads

Each time we use the pads, either for testing or for flight, the same process will be followed. Ogawa

sampler pads arrive in a refrigerated storage container where they are kept before use. They can be frozen

for up to a year before they expire, or can be kept, unopened, in standard refrigeration for ninety days.

Ogawa recommends the use of a standardized chain of custody form when working with the pads. This form

is available on their website as an Excel spreadsheet. Before flight, the pads will be removed from their long

term storage container with tweezers and placed into the shelter. Another pad will be taken out of

refrigeration simultaneously and kept isolated as a blank control. It takes the pads about 12 hours to slowly

come up to room temperature. After the pads reach room temperature they will be assembled within the

shelter and placed in a resealable, airtight, plastic bag until flight. The passive sampler can remain in the bag

without consequence for multiple days. Once GOAT is cleared for launch, and tUR is loading the HASP payload,

the passive sampler will be placed in the hull and the start time and date of exposure will be noted within

the chain of custody form. The pads are designed to work for exposures ranging from eight hours to multiple

weeks. The pads used in the experiment will be exposed from the moment they are added to the hull,

throughout flight, and then protected upon landing. As soon as possible after landing, the pads will be removed

from the sample housing with tweezers and placed into the brown glass vial that is used for safe storage. It

can remain in the bottle for up to four weeks before evaluation.

The Ogawa passive sampler has many advantages over other atmospheric gas collection methods that

were researched for this experiment. Its simple construction does not require a pressure vessel or electric

power. The pads are impervious to drastic changes in temperature and pressure. They remain unperturbed

through extreme heat and plummeting cold. The pads are hearty, crash-resistant, and indifferent to extreme

vibration; they would only be lost if a crash resulted in fire. The largest source of error and contamination of

the pads is moisture. Humidity must be monitored and controlled during refrigeration, climatization, storage

and flight. Silica gel desiccant packets will be stowed with the passive sampler in order to minimize available

moisture. The Arduino in the payload will record accurate time, temperature, and humidity data that will be

used to populate the chain of custody form in order to achieve the most accurate analysis of the passive

sampler pads. In the event that recovery of the HASP vehicle is severely delayed (such as by landing on the

edge of a ravine), the Ogawa passive sampler will be content to nestle in the hull until it is reunited with tUR.

Since the payload will launch as an open container, we would prefer that the Ogawa experiment be closed on

descent at around 12,000m from the ground.

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Fig. 5: NCCU’s Dionex ion chromatograph, to be used for chemical analysis of the Ogawa sampler pads.

After the samples arrive from New Mexico, either by hand or by mail, the research team will consult

with Dr. Bang to analyze the results. He will recommend one of two options for the team to proceed based on

the results of the flight. If it is advisable, the team would prefer to analyze the pads in their home lab. The

NCCU atmospheric lab has an ion chromatograph available for tUR to use to interpret the success of the

experiment. The stainless steel screens and cellulose pads will be removed from the brown vial and added to

a 25 ml stoppered Pyrex beaker containing 8mL water and agitated for 30 minutes. The next step is to pour

in 0.2 ml of Hydrogen Peroxide solution (1.75% solution). The stoppered beaker will be gently oscillated for

ten minutes. Before examination with the ion chromatograph the sample should rest at room temperature for

twenty minutes. Alternately, if Dr. Bang recommends it, the chain of custody form and the samples will be

sent a few miles away to RTI International for final evaluation for only $50.

The majority of the passive sampler testing will be structural since we are confident that accurate

results can be produced as long as the chain of custody is followed and proper protocol is used when handling

the pads. The research team will prepare by meeting with Dr. Bang for a tutorial on the pads and will help

him with his ongoing experiments in order to develop and appreciation of their application on the ground. A

blank placeholder pad and housing will be added to the payload contents during structural tests, vacuum

chamber and cryo testing in order to anticipate any negative impact the passive sampler might have on its

surroundings. A full Ogawa passive sampler will be flown during the tUR-3 high altitude balloon test flight in

Spring of 2017. The team will use this as a full dress rehearsal for preparing the pads, maintaining chain of

custody, and analyzing the results.

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Fig. 6: The launch of tUR-2 in June 2016. tUR-2 flew a digital sensor suite very similar to that planned for tUR-3 and GOAT.

Methodology for the Lactobacillus Microbes

Sulfur dioxide (SO2) is known to impact the growth of microorganisms, with varying degree of lethality

due to variables such as strain, morphology, and age. This characteristic has been researched for industrial

applications. Sulfur dioxide has also been studied and utilized in wine production as a restriction factor for

indigenous yeast and Lactobacillus.

GOAT would compare and contrast the growth and condition of microbial cultures sent to near space

with the control microbial specimens kept in approximately matching thermal conditions in the laboratory.

This is the most delicate, fascinating and experimental portion of our science experiment. Microbial specimens

will be included in the payload, including approximately three test plates of each specimen with each

specimen plate approximately 60 mm in diameter and 15 mm high and weighing approximately 7.4 to 7.8

grams (not including the weight of growth product).

After the flight we will be able to use the recorded ambient data to mimic the conditions experienced

during float in order to condition the growth period of the control microbes. The specimen plates from each

environment will be compared with one another to verify species and population within each environment.

The specimens will then be compared between the two separate environments. Any additional notes on the

differences between the specimens (i.e. morphology and condition) will be noted on review of the specimens.

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Lactobacillus cultures will be purchased from Fisher Scientific or Carolina Biological Supply. Multiple

media plates of Lactobacillus, fermented yeast, and spring yeast specimens will be prepared in advance of

the test. Lab testing will be done in the spring to determine the most reactive cultures and six total plates

from each group will be used for the experimental plates. This allows for three for control in the lab, and

three to be flown with GOAT from each specimen.

The team will document plates through notes, photos, and drawings in order to record plate conditions,

specimen count, morphology, and species. If possible, the plate conditions will be monitored with an onboard

camera during the flight and recorded with documentation; however, this is not required for the experiment.

The conditions of the specimens will be examined after the flight for plate conditions, specimen count and

morphology, etc.

Microscope, photos, and drawings will document the conditions of the lab control and test specimens

after the flight. Previous studies support that SO2 impacts yeast growth and younger specimens more than

established yeast colonies. The samples will be prepared and the juvenile yeast collected in early spring. If

juvenile yeast can not be collected in time for testing, standard baker’s yeast will be sufficient for the

experiment. During the flight, yeast spores may cover the sample compartment and its contents depending

on conditions during the experiment. No interference is anticipated between the other seats but if other HASP

participants are concerned, tUR will work with them to certify the scientific integrity of their experiment.

The agar will remain stable in the pressures that we expect from flight. Our specimens will remain viable from

-60°C to 60°C and if they freeze briefly it will not harm them. Research shows that the microbes will survive

being frozen for months at a time. Our thermal plan, below, discusses how we will keep the plates within the

optimal temperature range. The microbes will thrive unless they are in conditions that stop or slow their

aerobic respiration or make them switch to anaerobic respiration or lactic acid fermentation. This will dull

their performance but they will survive.

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Payload Systems & Specifications

Construction

GOAT’s three main experiment components (agar plates for microbiology, Ogawa passive sampler pads,

and Arduino sensor) will fly in a housing of aluminum 6061 fastened with stainless-steel bolts. We have

selected aluminum due to its relatively low cost, good weight-to-strength ratio, and its ease of machining.

Steel fasteners have been selected for their durability. While there will be significant thermal expansion and

contraction during the course of the flight, we do not expect the distances to cause failure from the additional

load on the hardware and do not anticipate the coefficient of thermal expansion (CTE) mismatch between the

two materials to be a problem.

The approximate deformation calculations below are based on the largest fastener diameter

(0.625cm), the coefficients of thermal expansion for the aluminum body and a stainless steel bolt, and the

possibility of a 110°C swing (-60°C to +50°C, from HASP 2016 data.) Results showed a negligible 2.3x10-5 m

deformation between the two materials:

δ = LαΔT where

L = diameter of aluminum plate in m ,

α = coefficient of thermal expansion of the material, and

ΔT = change in temperature in °C

Hole Deformation:

δAl = LαAlΔT = (0.290 m)(22.2*10-6)(110°C) = 5.15*10-4m

δ% = 0.000515𝑚

0.290𝑚 * 100 = 0.1776%

δhole = 0.00635 * 0.1776% = 1.1*10-5m

δsteel = LαsteelΔT = (0.006350 m)(17.3*10-5)(110°C) = 1.2*10-5m

δtotal = δAl + δsteel = 2.3*10-5m

Internal shelves will be made of either aluminum 6061 struts and sheet, or thin PVC board, as

conductivity needs require. For ease of manufacture and to keep costs low, almost all parts have been

explicitly designed from industry-standard stock with minimal modification, such as:

● 6063 Aluminum U-Channel, 1/16" Thick, 3/8" Base, 3/8" Legs, McMaster

● 6061 Aluminum 90 Degree Angle, 1/16" Thick, 1/4" x 1/4" Legs, McMaster

● 6061 Aluminum Sheet stock, 1/16” Thick, McMaster

● Steel (just for preliminary design; prefer aluminum) Inside Corner Reinforcing Bracket, McMaster

● Stainless Steel Corner Bracket with 5/8" and 1" Long Sides, McMaster

Most custom parts will be 3D-printed in ABS plastic. Only the motor requires a custom mounting plate in

aluminum, which will be made by the team machinist.

The hull will be lined with 6.35mm of insulating open-cell polyurethane foam which tUR has used with

success in the past. It will be non-hermetically sealed at ‘permanent’ joins with silicone caulk (cured in

vacuum) and at resealable joins with compliant silicone gaskets. Two large opposed vents, 7cm in diameter,

will direct airflow to the instruments.

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Caveats:

The following colorized figures (Figs. 7-10) are intentionally undimensioned. We have used shaded,

colorized images to make more human-readable accompaniments for the subsequent mechanical

wireframe drawings.

All fasteners and fastener holes have been left out or are arbitrary placeholders for position. As

such they are intentionally not dimensioned on all drawings. Ideally, for ease of manufacture, we

will standardize our payload to use only 2 or 3 screw sizes:

● “Small” 4-40 bolts

● “Medium” 6-32 bolts

● “Large” ¼”-20 bolts (likely only used for mounting to the HASP plate)

Dimensions in parentheses require no modification (i.e. Fig 14) and are only included for reference.

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Fig 7: Right (“side”) view with removable starboard plate hidden.

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Fig 8: Aft (“reversed front”) view with fixed aft plate hidden.

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Fig 9: Top view with removable top plate and upper 3-axis corner brackets hidden.

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Fig 10: Action of motor and driveshaft, depicted in its most-open configuration. We will launch with this all the way open and keep

it open for most of flight, only sending the command to close the jar when we are descending and below 12,000m. Items hued red

are fixed to the hull, while items hued green can slide along the rails.

The motor (A) is attached to the threaded drive shaft (B) with a weld or a machined set-screw. The drive shaft passes through a

thick threaded spacer (C), which is constrained to the hull via the cross-braces (D). The motor/shaft/jar assembly is constrained

from counter-rotation by three vertical rails (E) but can move freely up and down along them. As the motor turns and the shaft

drives downward, the jar (F) closes down over the trio of Ogawa canisters (G) which are fixed to the lid (H) which is, in turn, fixed

to the hull. Ultimately, the jar threads mesh and the lid is screwed shut.

Two crash-stop switches (not pictured) will help stop the motor from driving too far in either direction, and serial commands will

allow us to advance/reverse the motor incrementally in the event of a malfunction.

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Fig 11: GOAT fore panel

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Figure 12: GOAT aft panel

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Fig 13: GOAT top panel

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Fig 14: Reinforcing Bracket

Stress Analysis

We ran stress analysis on a simplified mockup of our payload to give a more conservative estimate of

the resilience of our hull. We modeled a shell of Aluminum 6061 with the same thickness as our hull in

Solidworks 2015. We loaded a 2kg block at the top-center for a dummy weight and ran a simulation of 10G

(~100N) force downward and 5G (~50N) laterally. The simulation does not have any brackets or other

strengthening fixtures, and is just testing the buckle strength of the hull alone. The simulation shows that we

are expecting a maximum strain of 4.862*106 von Mises, with the yield strength of our hull being 5.515*107 von

Mises. This is just a preliminary estimation to corroborate our intuition; we will do more detailed testing as

the model grows in detail. We will be particularly focused on the fasteners and materials immediately around

them, as these are common failure points.

We ran two simulations, one with a uniform inward radial shock of 5G (Fig. 15), and one with a lateral

shock of 5G (Fig. 16.)

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Fig. 15. Inward radial 5G force applied simultaneously with a 10G downward force on a simplified version of the hull.

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Fig. 16. Monodirectional 5G force applied simultaneously with a 10G downward force on a simplified version of the hull.

Thermal Control

GOAT is planning to primarily use the default power provided by HASP, only flying 2 AA batteries to be

used for the short time needed to drive the jar-closing motor; as such, our main sources of heat will be the

15W of power and the light from the sun. The Arduino defines both our minimum and maximum limiting

thermal factors. Given that our experience has shown this model of Arduino to cease operating at -35°C, we

are mandating that the interior stay between -25°C and 40°C. All other materials (aluminum, PVC,

polyurethane foam, steel bolts, Teflon wiring insulation, acrylic petri dishes, etc.) are rated within this

temperature range, as are our other experiment components. The Ogawa passive samplers can handle much

larger temperature extremes, and our biological cultures can survive easily within -60°C and 60°C.

Durham Tech owns a small vacuum chamber and an extreme temperature freezer that we can use for

testing but does not have both of these items in tandem. We plan to impose upon industry partner Paul Mirel

and borrow access to Goddard Space Flight Center’s temperature-controlled vacuum chamber to simulate

flight conditions roughly matching the following anticipated values. If access is prohibitive (due to logistics or

permissions) then we will construct a cruder home-made test chamber, following tutorials published by other

amateur balloon teams. tUR already owns a 5-gallon vacuum chamber capable of drawing sufficient vacuum;

we would build an insulating chamber with a variety of thermometers. Coiled, perforated copper tubing would

allow us to pour in cryogens as-needed to maintain desired temperatures. We have a source of liquid nitrogen

26

through NCCU, and the team lead is NASA-certified to handle cryogens. If all else fails, and we have not made

progress by March, we will contact Doug Granger at the LSU Bemco Balloon Environment chamber to get a

time and resources permit and make arrangements for a road trip to Louisiana. Additionally, we have a contact

at Cherry Point which is a much closer drive, but when we checked their chamber for tUR-1 it had a crack

that had not been repaired.

Temp (°C) Pressure (Pa) Expected duration

Early morning September launch from Ft. Sumner, NM

15 to 25°C 101,600 indefinite

Crossing tropopause -55°C 10,000 20 minutes

Float -30°C 500 to 2,000 10 to 16 hours

Crossing tropopause -55°C 10,000 20 minutes

Impact 20 to 30°C 100,000 instantaneous, we hope

Awaiting recovery 0° to 40°C 100,000 4 hours to 3 days

Fig 17: Flight Temperature and Pressure Expectations

If tUR thermal testing shows that staying warm i.e. above -25°C is a concern (as we currently expect)

we plan to fly Minco heaters due to their low weight, variety of form-factors, and flexibility for targeted,

efficient heating. We do not currently have a solid estimate for how much heating capacity we need but we

will focus on this during testing. Any heating or cooling elements will need to be autonomously controlled by

the Arduino due to the latency involved with any ground communication.

If our detailed thermal testing determines that dumping waste heat is a priority, the high thermal

conductivity of aluminum affords us the opportunity to use the hull as a heatsink. We would paint the hull

with aircraft-grade paint used by the PIPER mission on their radiator panels. This paint is very reflective in

solar wavelengths and very emissive in IR, and we would connect our major heat-generating components and

the hull with copper heat-straps and thermal paste.

If thermal testing shows that passive cooling is insufficient and that we must proactively handle both

extremes, we may need to investigate thermal switches to toggle the amount of heatsinking surface area used

at any given time.

Further testing will be required to verify that all materials do not cause chemical interference with

any of our three sensor options, especially under flight temperatures and pressures. In the event that our

testing reveals any such interference, we are confident in being able to find alternatives which meet our

specifications.

Airflow

Our hull will be sealed for the launch in order to maximize the structural integrity of the payload. The

hull walls will feature two opposed 9cm mesh-covered vents in order to encourage airflow into the science

experiment. Adjustments will be made after testing if we discover that we need to optimize the airflow or

adjust the vent specifications to maintain our thermal profile.

27

Our research indicates that none of our three sampling methods require forcing air across them or

using a fan to achieve the necessary atmospheric exposure. For this reason and to keep power requirements

simple, we have left off any fans or pumps. Future versions may include them if our testing warrants such a

consideration.

Other Risks

Our payload design contains no radioactive materials, lasers, cryogenic materials, high voltage, strong

magnets, pyrotechnics, intentionally dropped components, or hazardous chemicals.

We are flying 2 Energizer Lithium AA batteries for supplemental power for our motor. These will be

discharged within their recommended parameters. We have flown them on previous tUR missions without any

issue of fire or other electrostatic problems.

Our only ‘pressure vessel’ is the Nalgene jar containing the Ogawa passive samplers, which will be

sealed at ~12,000m during descent; we do not consider this a threat to the sturdy sample jar, and will confirm

this with tests. Even in the event of a rupture, the jar is small (~270 mL), will only fail inward (i.e. implode

rather than explode), and will be contained by a metal hull; we do not foresee this endangering any other

parts of HASP.

Our biological samples are commonly used worldwide in home settings and are not considered unduly

infectious or hazardous. The petri dishes we are using are opaque to the intense UVA/UVB radiation which

might otherwise be harmful to them, and are further shielded from too much direct light exposure by their

enclosure.

Grounding & Electrical Insulation

All components will be grounded to the hull. Shared grounds will be used where advisable to avoid

ground loops. All electronics will be mounted on nonconductive standoffs to avoid shorts, and all cables will

be bundled, then laced and/or sheathed with braided insulation, and zip-tied or snap-locked into place along

the hull interior to prevent loose wiring or strain on the connectors. All solder joins will be insulated with

heat-shrink.

While we have not had issues with arcing on previous flights, it remains a very real concern at these

altitudes; so we will test various commercial spray-on anti-arcing coatings to ensure they do not contaminate

our chemical samples. If that proves unhelpful, we may laminate sensitive components or add a thicker

silicone anti-arc layer.

Moving Parts

Moving parts add risk simply by not being nailed down and are further susceptible to CTE mismatches

and ice accumulation. Furthermore, the motor has one of the larger power requirements on the project. GOAT

has minimized this by only designing in one moving part, which consists of a motor-driven threaded shaft

connected to a jar lid. As the motor turns the shaft, the threaded rod pushes the jar lid onto the top of the

jar, marries the threads, and screws the jar shut. Care will need to be paid to match the rotation, thread

depth, and thread pitch of the threaded shaft with the threads on the jar (see Fig. 10 above.)

As a stretch goal, we will try to add doors to our two large side vents. These doors would seal after

landing to keep as much ground contaminants (dust etc.) out of the payload while it awaits recovery. We will

approach this design challenge after other, more crucial systems are further along in the development process.

28

29

Payload Integration

GOAT requires no modifications to the mounting plate at this time. We do not have a preference for

payload orientation; our only positional concern is that our vents not be blocked. Pictures and diagrams of

HASP suggest that none of the 8 small payload sites should be a problem.

Mass Budget

Component Quantity Mass (g) Error (+/- g)

Frame & Hull 1 982 250

6060 Al. Sheeting (summarized) -- --

1/4"x1/4" 1/8" Al. angle stock (summarized) -- --

Fasteners (summarized) -- --

0.15875cm Al Mesh 150 cm^2 20 2

0.5 cm Foam Board 900 cm^2 90 10

Internal Fittings

7.9 OD 4.9 ID Tubing (standoffs) 5 2cm pieces 13 2

AGAR Plate Box .3175 PVC Board

1.27x10.16 cm Hose Clamp 1 14 1

Ogawa Assembly

3D-printed ABS bracket 3 36 2

Ogawa Samplers w/ Jar 3 100 10

Arduino Assembly

Arduino Mega 1 37 0.1

AM 2315 Barometric/Temp Sensor 1 49 0.1

Recessed Sensor Housing 1 44 0

SPEC SO2 Sensor 1 4 0.1

Agar Plates 6 276 50

TMP006 Infrared Internal Temperature Sensor 1 0.0026 0

Sparkfun Standard Gearmotor 1 128 1

Barometric Breakout Sensor SEN-09721 1 1 0

Si5351A Clock Generator 1 2.5 0

Miscellaneous

1.27cm 90 Brackets 7 42 5

1.905 x 7 Rubber Strip 1 38 2

Guide Bracket 1

Green Polyurethane foam 2300 cm3 26 2

Fasteners (estimate for entire payload) * 125 250 25

Wiring 100 5

PTFE Membrane Filters 1 3 0

Silica gel desiccant packets 4 12 0

Silicone caulk 8 1

Silicone gaskets 5 1

Lithium AA Batteries 2 46 0

1 2.5 0

2253.0026 367.3

Fig 18: Mass Budget

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Data Handling

The payload will take advantage of the serial downlink and uplink automatically, with no usage of

discrete commands other than the default ‘power on/off’ as specified in the HASP Manual. Information will

be stored in a single package of data outlined in figure 20 at 1 Hz. The design of this package will allow for

multiple sensor readings to be stored within. This gives the opportunity to send multiple readings to the ground

per second. The individual sensor readings that will be placed inside the data portion of the package will be

standardized into a uniform size of 20 byte chunks (this may include adding padding to some of the sensor

reading packages). The 20 byte uniformity will allow for the sensor readings to be easily interchanged based

on priority or any other later decided-upon criteria. The size also allows for four sensor readings to be sent to

the ground per package. The total size in bytes of the package is 133 bytes. This size accounts for having

proper time stamping, checksum, data, and a recommended terminator. The package of this size also takes

into account the required 1 bit for a stop after each byte (8 bits) sent down. Formatting the data in this

manner will allow the payload to take full advantage of the provided baud rate of 1200. In addition to using

the entirety of the baud rate provided, the design of the package grants the package the ability to guard

against any concerns surrounding bit corruption. It will provide the option of sending only two different sensor

readings per package. In this scenario, there will still be four sets of data but two will be repetitions; this

gives us the ability to focus on integrity of crucial readings in the event of sustained corruption.

Since the payload will launch as an open container, we would prefer that the Ogawa experiment be

closed on descent at around 12,000m from the ground. To facilitate this, the Arduino will take advantage of

the GPS data provided through the HASP flight system at the requested interval of once per minute. The

Arduino will keep track of the balloon’s altitude internally and analyze multiple data points to determine

whether the payload is ascending or descending at any given time. It will also ensure that the system does not

close the Ogawa experiment at 12,000m on the ascent. The algorithm will send a special sensor packet to let

the ground know exactly when it initiates the ‘close’ command.

As a second “stretch goal” we are considering flying a keychain camera for visual confirmation /

troubleshooting of the door operation; we would use a serial command to take an on-demand picture of the

payload interior and based on the results of said picture, will use another serial command to attempt to close

the experiment “manually.” For redundancy, there will be uplink commands programmed into the Arduino to:

● take and send a picture with the LED flash turning on before and off after shutter time

● advance/reverse [one separate command for each] the motor for 0.1 second at low speed and max

torque

● advance/reverse the motor for 0.1 second at normal speed and normal torque

● advance/reverse the motor for 1 second at low speed and max torque

● advance/reverse the motor for 1 second at normal speed and normal torque

● advance/reverse the motor for 5 second at low speed and max torque

● advance/reverse the motor for 5 second at normal speed and normal torque

● advance/reverse the motor for 30 second at low speed and max torque

● advance/reverse the motor for 30 second at normal speed and normal torque

● advance/reverse the motor for 60 second at low speed and max torque

● advance/reverse the motor for 60 second at normal speed and normal torque

● advance/reverse the motor for 300 second at low speed and max torque

● advance/reverse the motor for 300 second at normal speed and normal torque

● advance/reverse the motor for 600 second at low speed and max torque

● advance/reverse the motor for 600 second at normal speed and normal torque

31

● advance/reverse the motor for 900 second at low speed and max torque

● advance/reverse the motor for 900 second at normal speed and normal torque

A spoof serial uplink will be employed in order to test both options by sending “dummy” information

through the serial uplink. Both instances of closure via the spoof serial uplink will be enacted inside of a

freezer at -40 degrees C and under vacuum to ensure functionality. As an additional stretch goal, we will

implement a physical switch to tell the Arduino when the jar-sealing mechanism is at either extremum of its

potential travel distance, giving us further feedback about the operation of our single moving part.

At time of integration between the EDAC 516 cable and the HASP gondola, the payload will be powered

on and monitored to make sure the payload is not drawing an excessive amount of current (0.5 A). It will also

be important at this time to make sure the regulator is working properly with the supplied voltage of the

gondola.

In addition to the regulator, we are considering employing our own internal circuit breaker; right now

we do not believe our system is granular enough to warrant (or to properly take advantage of) one. We are

more likely to either individually fuse our power-intensive units (the motor to seal the Ogawa sampler is

desired but not mission-critical for the integrity of that experiment) or to focus our efforts on proactively

debugging any possible power spikes or shorts. It will be important for the team to test the entire system in

near-vacuum and in lower temperatures, especially given the propensity of higher voltages to arc with reduced

conductive resistance of lower temperatures. During integration, the team would also like to test the

commands through the serial uplink in order to ensure that there are no peculiarities between the gondola

and the testing rig that will be setup for the team’s own testing of the payload. Thus, the setup process will

look like:

1. Bolt GOAT to Gondola.

2. Plug in fresh set of test AA’s.

3. Hook up EDAC 516 cable.

4. Hook up Serial DB9 cable.

5. Power on GOAT.

6. Use Clamp-On Ammeter in order to monitor amperage draw during testing.

7. Test as many Serial Uplink Commands as time and common sense allows.

8. Spray small puff of aerosol SO2 near our digital sensor for integration bump test.

9. Verify readings are coming through Mini-SIP to ground control.

10. Power off GOAT.

11. Unhook EDAC 516 cable.

12. Unhook DB9 cable.

13. Remove AA’s.

32

Flowchart

Fig 19: Software Flowchart

A full-resolution image is available here. Thermal control removed from this chart for simplicity.

33

34

Data Packet Composition

Byte Title Description

1-8 Time Time collection was sent.

9-10 Size Size of the package coming down.

11 Checksum Least significant 8 bits of the record checksum.

12-131 Data Actual package data: multiple sensor readings (see figures 21-23).

132-133 Terminator Terminator will be “\x3\xD”.

Fig. 20: The package that will be transmitted to the ground through serial downlink.

Byte Title Description

1 Type Type of structure used to interpret this data.

2-9 Time Time reading was taken.

10-13 VRef Voltage the sensor had when reading was taken.

14-17 VGas Actual output from the sensor.

18-20 Terminator Terminator will be “\x3\xD\xA”.

Fig. 21: The package byte arrangement for the sulfur dioxide readings.

Byte Title Description

1 Type Type of structure used to interpret this data.

2-9 Time Time reading was taken.

10-13 Humidity Reading from the AM2315: external humidity.

14-17 Temperature Reading from the AM2315: external temperature.

18-20 Terminator Terminator will be “\x3\xD\xA”.

Fig. 22: The package byte arrangement for the AM2315 sensor.

Byte Title Description

1 Type Type of structure used to interpret this data.

2-9 Time Time reading was taken.

10-13 Temperature Reading from the TMP006: internal temperature.

14-17 Padding Padding to keep data length uniform.

18-20 Terminator Terminator will be “\x3\xD\xA”.

Fig. 231: The package byte arrangement for the TMP006 sensor.

35

Byte Title Description

1 Type Type of structure used to interpret this data.

2-9 Time Time reading was taken.

10-13 Pressure Reading from the MPL115A1: internal barometric pressure

14-17 Padding Padding to keep data length uniform

18-20 Terminator Terminator will be “\x3\xD\xA”.

Fig. 24: The package byte arrangement for the MPL115A1 sensor.

Preliminary Drawings

Fig. 25: Wiring Diagram

A full-resolution image is available here. We have intentionally left our Minco heating elements off the

wiring diagram pending further clarification for how much will be needed.

Power Usage

Device (purpose) Voltage (V) Current (mA) Power (W) Time On

Arduino Mega 2560 rev3 (processor & board)

12 50 0.6 Entire flight

Adafruit AM2315 (external atmospheric sensors)

5 10 0.05 Entire flight

36

Adafruit microSD breakout [Product ID: 254] (SD card interface)

5 200* 1 Intermittent

Spec Sensors Ultra-low power Analog Sulfur Dioxide Sensor [Digikey PN: 1684-1023-ND] (primary digital SO2 instrument)

3.3 0.01 0.00003 Entire flight

Adafruit TMP006 Infrared Thermopile Contactless Temperature Sensor [Product ID: 1296]

5 10 0.05 Entire flight

Adafruit Si5351A Clock Generator Breakout Board [Product ID: 2045]

3.3 45 0.1485 Entire flight

SparkFun Barometric Pressure Sensor Breakout SEN-09721

5 10 0.05 Entire flight

Polyimide Thermofoil Heater (Rated for 5W) 30 125 3.75 Ascent and descent (2 hours each way)

GOAT Battery Power: 2 AAs (3.0V, 3500 mAh)

SparkFun Standard Gearmotor ROB-12367 (seals Ogawa sampler jar)

5 208 1.04 < 15 minutes

SparkFun tinyESC ROB-13204 (controls Gearmotor)

5 100 0.5 < 15 minutes

* normal mode draws 100 mA, high-performance ‘fast-write’ mode draws 200 mA, but other users have reported seeing higher

spikes.

Fig 26: Power Budget

We are planning to turn off power-intensive elements for the short interval while the motor is running.

With our finite power budget, after the automated closing mechanism or the uplink command is sent, sensors

will remain inactive and not queried by the Arduino for twice the amount of time (to account for any

discrepancies that may appear between the actual experiment environment and our test-driven predictions)

it takes for the jar to successfully close. This time will be discovered through testing.

37

Risk Management

high

S

E

V

E

R

I

T

Y

low

F. Improper instrument calibration

G. Personnel Burn-Out

B. Bad electrical insulation causes fatal

short / spike

C. SD card does not write

A. Wiring / software bug

causes surge / blows HASP fuse

L. Lack of access to a local professional

thermally-controlled vacuum chamber

M. Unfortunate landing fatally delays recovery

H. Behind Schedule

I. Something breaks in Ft Sumner (where there is no means of getting it

replaced)

D. Atmosphere too thin to collect interesting data for SPEC sensor

baseline

N. Insufficient funding

J. Ogawa jar sealer mechanism fails

E. Lack of dedicated junior/senior electrical

engineer

P. GOAT’s application not accepted / First

ever HASP scrub? O. Personnel drop-out

K. Mishandling of experiments during loading / recovery

low P O S S I B I L I T Y high

Fig 27: Risk Matrix

Mitigation strategy: A. Wiring/software bug - Exhaustive, methodical testing is the best way to catch something like this before flight.

B. Bad insulation - Use shrink-wrap insulation on solder joins, use spray-on anti-arc coating, and test test test.

C. SD card write issue - Loose wiring has ruined data on past flights. We will be keenly attentive to good cable routing.

D. Atmosphere too thin - We learn valuable information about the sensitivity of our SO2 measurement methods for GOAT-2.

E. Lacking senior Elec Eng - We are in the process of recruiting for this position and have reliable mentorship.

F. Improper calibration - Post-process the data as well as we can if we know what went wrong. Fix for GOAT-2.

G. Personnel burn-out - We have built several ‘crumple zones’ into the schedule, leaving time to stop development and let our

people rest. We’ve worked with each other enough to recognize/speak up about overload and re-balancing tasks.

H. Behind schedule - GOAT is actually on-schedule now. Proper management / scope-cutting are the best mitigators.

I. Crucial part failure - Ft. Sumner is relatively isolated. We will bring backups of all crucial parts, but in the event of serial

failure we may pay for same-day shipping, borrowing from CSBF, or attempting delicate repair ourselves.

J. Jar sealer fails - The Ogawa samplers will still function; we will have to post-process more if the jar doesn’t close.

K. Mishandled experiments - We have a range safety officer to enforce best-practices (ESD bracelets, gloves, etc.) and will go

into the field with detailed checklists to ensure we do not miss something in the adrenaline of the moment.

L. Vacuum chamber - As mentioned above, we will build our own or use the Bemco chamber in LA.

M. Delayed recovery - There is not too much we can do to mitigate a delayed desert recovery in baking sun; we are coating the

hull with reflective paint and designing it to withstand up to 60°C.

N. Money - We have firm offers of more funding from Dr. Bang’s grants, and tentative offers from Dr. Cecil. We are still

working out details. We are also negotiating with a major industrial manufacturer to have them sponsor our test flight.

O. Personnel drop-out - We will call up talented students from Science and Engineering club.

38

P. Not accepted - If our HASP application is not accepted, or if HASP is scrubbed due to weather for the first time in 12 years,

we are resolved to fly a slimmer version of our payload on a 1200g latex balloon in a styrofoam hull.

39

Team Structure and Management Narrative

Last year Durham Technical Community College (Durham Tech) formed a team for the NASA NC Space

Grant Competitive Suborbital Unmanned Spaceflight (CSOUS) competition called “The Unacceptable Risks.”

The Unacceptable Risks (tUR) worked together on their balloon payload for an academic year. This high

altitude launch, tUR-1, flew an Arduino sensor suite, a radiation dosimeter, a hacked Canon, a GoPro,

advanced telemetry, and space cookies. The payload was successfully retrieved with all data still recording

and the cookies still delicious. During the summer the team reprised the contents of the payload and launched

tUR-2.

After a successful launch and recovery the team went on to win “Best Documentation” from NC Space

Grant for their outstanding Critical Design Review presentation, Launch Readiness Review presentation, a 52

page Post Launch Assessment Review report, project notebook, scientific poster and other accompanying

documentation. Many of the students from this team graduated from Durham Tech and transferred to local

universities, including the University of North Carolina at Chapel Hill (UNC), North Carolina Central University

(NCCU), and North Carolina State University (NCSU). Despite their commitment to their studies and the

logistics involved in travel between the various locations, they decided to persist with their balloon research

and have continued to plan, engineer, and launch experiments.

Members of tUR are currently working on a few other interesting projects together. Several students

are contributing to a drone project using remote sensing to study solid debris as non-point-source water

pollution, and others are participating in the University of New Mexico NASA Swarmathon Competition.

Graduation has not divided the team. In fact, tUR has been using these other projects to identify and recruit

other intelligent and dedicated students with an interest in aerospace research. The team sees itself as a

local, non-profit, amateur space agency and is arguably the most recognized High Altitude Ballooning brand

in North Carolina. Over the past few months tUR has been asked to present a poster at an event sponsored by

the Center for the Advancement of Science in Space (CASIS), speak at the Greensboro Science Cafe, appear

as guests on a radio show, meet an astronaut, volunteer with NC Near Space, and present the keynote talk at

the NC Space Grant board luncheon during the State of North Carolina Undergraduate Research and Creativity

Symposium.

One benefit of starting in a community college setting is the diversity of the team in terms of age,

ethnicity and variety of skills. The majority of the team is composed of mature, “non-traditional” older

students who have a professional background of work experience to draw on for the organization and structure

of the team. These students are motivated by the experience of the project and signed up for it with a clear

idea of the expected time commitment.

A competition like HASP requires hundreds of hours of work and having team members that are reliable

and who understand each other's personal dynamics, cadences, strengths and foibles can make the project

run smoothly and increase the likelihood of a successful outcome. Communication has always been one of

tUR’s strengths. The HASP project will be a challenge to complete but tUR will rely on the systems already

in place to manage the workload. All of the students reside in the Triangle region of North Carolina and

transferring to different schools has only improved the team dynamic by giving the tUR access to more

computer labs, maker spaces and machine shops. The team frequently meets for in person planning and

building days but also relies on a massive Google Drive for working remotely. While tUR is actively engaged in

planning a project, or writing an application, the team holds weekly “All Hands” Google Hangout video

conference calls.

40

The team is sponsored by Julie Hoover, an instructor of geology with a Masters of Geological

Engineering, who mentored the team throughout CSOUS and leads the projects mentioned above. Ms. Hoover’s

thesis research was funded by a fellowship through the Mississippi Space Commerce Initiative at Stennis Space

Center. She is also the mentor of the Durham Technical Community College Science and Engineering Club. She

has worked with the members of tUR and has a high standard for excellence and a proven track record of

completing large, multifaceted projects on time.

Dr. Kathy Zarilla, Dr. Dorothy Wood, and Chris Mansfield are other faculty at Durham Tech who will be

assisting with the project.

Team Members

Jimmy Acevedo will be the student team lead. He is a physics major at North Carolina Central

University, a NASA Community College Aerospace Scholar, a NC Space Grant STEM Community College Scholar,

a NASA Space Public Outreach Team ambassador, and a Technician-class HAM radio operator. Jimmy interned

at Goddard Space Flight Center during summer 2016 on the Primordial Inflation Polarization ExploreR (PIPER)

balloon project; they have invited him back to work for a second summer in 2017. He also brings five years of

software development and project management experience from his time working at Electronic Arts.

Ms. Hoover and Jimmy visited CSBF in Ft. Sumner this fall to participate in PIPER’s engineering flight.

We observed balloon facility operations and learned our way around the shop. We spent late nights working

in the hangar, attended daily weather briefings, avoided hares on the tarmac, and helped the PIPER team

prepare for rollout. This experience will be an invaluable resource while decoding the project requirements,

preparing for launch, troubleshooting for flight, getting to the facility, and working with CSBF personnel.

Fig 28: A gorgeous morning in Fort Sumner.

The science and research team is made up of Alicia Sullivan, Gabrielle Richardson, Ian McDaniel, and

Christine Meyer. Ian updates our website, curates the tUR media folder, and is famous for his rapid response

to research assignments. Alicia and Gabby are geology and environmental science majors who are focused on

41

the results of the Arduino sensors and the Ogawa sampler and will be working with Dr. J.J. Bang in the

atmospheric laboratory at NCCU. Alicia has research experience from completing two field excursions with

UNC, one on the North Carolina coast and one in the Everglades. Christine has a MS in geology and a

professional background in environmental science. She has returned to school to pursue her love of

microbiology and is a student learning proper technique in microbiology from Dr. Wood. She received a BS and

MS in Geology and previously completed research with NASA through Nathan T. Bridges (Jet Propulsion

Laboratory) at the Ames Research Facility in Mountain View, California.

Dan Daugherty is a mechanical engineering major at NCSU and leads the engineering team. He draws

from a lifetime of mechanical experience working with small engines through motorcross and the auto

industry. His innovative launcher design won the engineering challenge for his class at NCSU. The programming

group is composed of Erick Ramirez, Ryan Theurer, Dan Koris, and Mohamed Karoui. Erick has written apps

for Food Lion, a regional grocery chain. Ryan became an expert on high altitude ballooning for tUR-1. Dan

created, managed, and coded for his own private gaming community of around 100-200 people. Mohamed

investigated the application of techniques used in thermo, fluid, classical electro, and molecular-dynamics to

create an AI that uses a small “template” decision tree that can be transformed through a series of vector

operations in order to adapt rather than account for all possible circumstances.

The electronics and mechanical technicians are David Cardwell, Ryan Hull, and Seth Close. David did

all of the wiring for tUR-1 and tUR-2 and is the student team lead of the 2017 CSOUS mission. Ryan worked

with student at NC A & T to engineer a car that will have radically more efficient gas usage. Seth has built

an entire UAS platform from scratch including many parts that he designed and 3D printed himself and has

experience with microelectronic wiring.

We anticipate sending Ms. Hoover, two students, and the two student team leads to integration at

CSBF. We hope to send Ms. Hoover and at least three students for the flight in Fort Sumner, NM.

Left to Right: Mohamed Karoui, Christine Meyer, Dan Koris, Alicia Sullivan, Julie Hoover, Jimmy Acevedo, Ryan Hull, Dan

Daugherty, Gabby Richardson, Vincent Davis. Not pictured: Ian McDaniel, David Allen Cardwell, Erick Ramirez and Seth Close.

Fig 28: The Unacceptable Risks

42

Financial Support

NC Space Grant has awarded tUR $5000 as part of the Team Initiative Grant. This grant is designed to

help student teams succeed at opportunities like HASP that are unfunded. The team has other fundraising

options for travel including industry partners, the Durham Tech Foundation, and community partners.

Necessary supplies for the project should be possible to procure within a reasonable budget because the team

is composed of tinkerers with dedicated tool sets and materials. Having three schools’ worth of resources and

workspaces to choose from will give tUR many fabrication options. Students in the group have working

knowledge of computer labs, machine shops, libraries, and Maker Spaces on all of the campuses and are

accustomed to working and collaborating on projects across campuses.

One of the greatest challenges of this project for tUR will be travel to CSBF in New Mexico. The students

that make up tUR have pledged to find their own way to Fort Sumner if the opportunity arises. A plan is in

place if comprehensive travel funding is not available. Driving to Fort Sumner takes about 24 hours each way

and campsites are available at nearby Lake Sumner. While this is not ideal, tUR considers it to be an acceptable

risk.

43

Fig 30: Organizational chart

44

Name Team Role/Title Email Address

Julie Hoover Faculty Sponsor Principal Investigator

hooverj@durhamtech.edu Collins Building 1637 Lawson St Durham, NC 27703 919-536-7223 x8021

Dr. Dorothy Wood

Faculty Sponsor Microbiology

woodd@durhamtech.edu Orange County Campus, 525 College Park Road, Hillsborough, NC 27278 919-536-7238 x 4225

Dr. Kathy Zarilla

Faculty Sponsor Chair, Science Department

zarillak@durhamtech.edu Collins Building 1637 Lawson St Durham, NC 27703 919-536-7223 x 8048

Christopher Mansfield

Faculty Sponsor Chair, Math and Engineering Department

mansfieldc@durhamtech.edu Collins Building 1637 Lawson St Durham, NC 27703 919-536-7223 x 8026

Dr. John J. Bang

Faculty Sponsor Atmospheric Science

jjbang@nccu.edu 2105 Mary M. Townes Science Building 1900 Concord St, Durham, NC 27707 919-530-6569

Jimmy Acevedo

Physics Undergraduate

jaceved1@eagles.nccu.edu 200 W. Poplar Ave #6 Carrboro NC 27510

Ryan Theurer Information Science Undergraduate

ryantheu@live.unc.edu 3 Lanark Rd Chapel Hill, NC 27517

Ryan Hull Physics / Industrial Eng. Undergraduate

hullr6112@connect.durhamtech.edu 210 Hillview Dr Durham NC 27703

Erick Ramirez Computer Science Undergraduate

ramireze3685@connect.durhamtech.edu

409 Rodham Rd Durham, NC 27703

Daniel Daugherty

Mechanical Engineering Undergraduate

dadaugh2@ncsu.edu 3821 Knickerbocker Pkwy, Apt J Raleigh NC 27612

David Cardwell

Electrical Engineering Undergraduate

davidallencardwell@gmail.com 2330 Stroller Ave Durham, NC 27703

Alicia Sullivan Geology Undergraduate

Asull411@gmail.com 716 Holloway Street Durham, NC 27701

Gabrielle Richardson

Environmental Science Undergraduate

gmrich94@gmail.com 111 Stardale Road Morrisville, NC 27560

Ian McDaniel Communications Undergraduate

ianwmcdaniel@gmail.com 200 Alexan Dr., #305 Durham, NC 2770

Christine Meyer

Microbiology Undergraduate

meyerc4855@connect.durhamtech.edu

2523 Creek Ridge Lane Chapel Hill, NC 27514

Daniel R. Koris

Computer Science Undergraduate

korisd@gmail.com 2804 Elgin St. Durham, NC 27704

Mohamed Karoui

Electrical Engineering Undergraduate

mfkaroui@gmail.com 4512 Pale Moss Drive, Raleigh, NC 27606

Seth Close Mechanical Engineering Undergraduate

seth.d.close@gmail.com 2835 Fox Drive Durham NC 27712

45

Kory Menke Student Engineering Mentor Undergraduate

kjmenke@ncsu.edu 2 Cobble Glen Ct Durham, NC 27713

Vincent Davis Applied Math Mentor Graduate Student

chenzo513@gmail.com 111 Stardale Road Morrisville, NC 27560

Paul Mirel Industry Partner Chief Engineer for the NASA PIPER mission, a contractor employed by KBRwyle

paul.mirel@gmail.com Goddard Space Flight Center Building 21 RM 71 8800 Greenbelt Rd. Greenbelt, MD 20771-2400 301-312-0213

Jobi Cook Industry Partner NC Space Grant

jobi_cook@ncsu.edu Campus Box #7515 North Carolina State University Raleigh, NC 27695-7515 919-515-5933

Dr. L. DeWayne Cecil

Industry Partner Founder and Chief Scientist Sustainable Earth Observation Systems, LLC An Earth and Space Community Resource/ NOAA/ Chief Climatologist for Global Science & Technology, Inc.

seosllc@gmail.com Sustainable Earth Observation Systems 116 Depot St Waynesville, NC 28786 801-891-1161

George Hoover

Industry Partner The InnovaNet Group Senior Advisor, Mechanical Engineering

hoover4740@gmail.com 510 Nina Dr Graham, NC 27253 336-512-9831

Dr. Eric Saliim Industry Partner NCCU Fab Lab

esaliim@nccu.edu 2101 Mary Townes Science Complex 1900 Concord St, Durham, NC 27707 919-530-6263

46

Timeline and Milestones

October 2016

23 Science Experiment Meeting

November 2016

11 Q & A Teleconference

13 All-Hands Experiment Meeting

16 Engineering Meeting

18 Leadership Engineering Meeting

20 All-Hands Google Hangout

27 All-Hands Google Hangout

30 Engineering Team Meeting

December 2016

01 First Draft Due

04 Leadership Google Hangout

04 Engineering Team Meeting

05 Engineering Team Meeting

06 Research Team Google Hangout

07 Programming and Wiring

09 Write-a-thon

10 Final Draft Due to Jimmy Acevedo

12 Draft to industry partners

16 Application due

17 tUR Application Conclusion Party

January 2017

~15 Announce student payload selection

22 All-Hands Meeting (Order Supplies)

29 All-Hands Google Hangout

January TBD Monthly status reports and

teleconferences

February 2017

05 Unboxing of supplies and Build Day

12 Build Day

15 Microbial training at Orange County Campus

17 Ogawa Sampler training at NCCU

February TBD Monthly status reports and

teleconferences

30 PSIP Document goes live for contribution

March 2017

01 Cryo and Vacuum Testing begins

March TBD Monthly status reports and

teleconferences

April 2017

13 PSIP Draft 1 due

17 PSIP Final Draft due

21 Durham Tech Honors Symposium

28 Apr 2017 Preliminary PSIP document due

April TBD Monthly status reports and

teleconferences

May 2017

13 tUR-3 HAB Test Launch

15 tUR-3 PLAR, begin lab work

18 Repair day

May TBD Monthly status reports and

teleconferences

June 2017

23 Final PSIP document due

24 FLOP live for contribution

June-Aug TBD Testing at Goddard Space Flight

Center

June TBD Monthly status reports and

teleconferences

July 2017

05 FLOP Draft 1 due

18 FLOP Final draft due

28 Final FLOP document due

July TBD Monthly status reports and

teleconferences

31 Payload integration at CSBF

August 2017

04 End Payload integration at CSBF

14 Classes in session

August TBD Monthly status reports and

teleconferences

September 2017

01 Sep - 05 Sep 2017 Flight preparation

06 Target flight ready

07 Target launch date and flight operations

08 Recovery, packing and return shipping

14 tUR GOAT PLAR

15 Science Team begins lab work

September TBD Monthly status reports and

teleconferences

October 2017

30 Data Due

October TBD Monthly status reports and

teleconferences

November 2017

01 Final report live for contributions

TBA SNCURCS Presentation

27 Draft Due

47

November TBD Monthly status reports and

teleconferences

December 2017

08 Final Flight / Science Report due

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