Supernova Brigade Final Presentation Amanda Kuker, Michael Lotto, James Bader, Jordan Dickard, Blake Firner, Diana Shukis Rev

Mission Overview –To determine the relative light intensity throughout the atmosphere and compare it to the efficiency of solar cells. –We expected to discover that solar cells are more efficient (put out higher current) at higher altitudes and greater light intensities.

Design Overview

Differences from proposal –LEDs wired backward → Light Intensity Sensor –Solar cells wired to board → Current Sensor → Resistors

Results and Analysis

Predicted –Current output would increase with increasing light intensity/altitude –Light intensity would increase with altitude Actual –Current Sensor did not function as expected –Light intensity increased slightly with frequent oscillation between minimum and maximum values

Results and Analysis

Light Intensity Trends –Increased slightly between the ground and the time at which it remained constant –Remained constant for a period of time –It increased slightly and reached the maximum value –Plummeted and stayed at a constant low level until burst

Results and Analysis

Failure Analysis Current Sensor/ Solar Cells There were not enough solar cells to obtain accurate data. Covering more surface area of the satellite would provide us with more consistent and usable data. The current sensor was calibrated for 100mamps and there was a maximum of 200mamps entering the current sensor. This would not have affected the data retrieved but it would have affected the converted output of mamps. The resistors may have been calculated wrong for the optimization of the solar cells. The solar cells used were not the best choice for our experiment. Solar cells that laid flat would not have had issues with shadows from the walls of the casing.

Failure Analysis

–System was tested again in complete darkness and in light again to see if data was altered accordingly. –Data remained the same therefore we know it was not a one time failure. –Failure has not been fixed, need more solar cells, more resistors and materials of which cannot be acquired due to budget.

Conclusions Light Intensity intensity does not increase directly in relation with altitude remains generally constant ascends through the Troposphere reads its maximum value after ascends through the Tropopause sensor was not sensitive enough, so we don’t know if it would have kept increasing or stayed constant at a new level Either way we conclude that after passing through the Tropopause the light intensity increased.

Conclusions Solar Cells solar cells are more efficient in colder temperatures so solar cells would be more efficient at certain altitudes Based on our data the temperature increased toward normal ground temperatures as the satellite ascended Further research revealed the temperature between km is around -2°C (winter day in Colorado) we assume that solar cells would be as efficient at km as they are on a winter day. no clouds to block the sunlight, work better at altitude than on ground light intensity increases after tropopause, temperature optimal we can assume that the solar cells would indeed be more efficient at altitude than operating on the ground.

Lessons Learned Teamwork is essential to mission success Thorough and complete research of the circuitry helps improve the construction process Checking our work with someone more knowledgeable is important If the team could have a chance to repeat the project… an electrical engineering expert would have been sought out before the proposal deadline asked a Space Grant student or other expert for suggestions to ensure the optimization of in-flight data retrieval Determined possible ways to isolate the sensors from the shade produced by the tilt of the balloon satellite.

Ready To Fly Again To store the balloon satellite, a room with 20 degrees Centigrade and no hazards that can crush the balloon satellite is required. Other than that, no special needs are requested for storage. To activate the payload, simply arm the AVR Board, using the data utility program, and flip the G-Switch and Power Switch to the “ON” positions (labeled on the satellite). One concern for the longevity of the balloon satellite is the adhesive side of the Velcro losing the ability to attach the batteries, heater, and AVR Board to the structure. If the satellite is not launched within the next six months, the Velcro within the satellite will need to be replaced.

RFP/Proposal/Requirement Compliance Matrix The following requirements have been considered and factored into the design of the BalloonSat. The major requirement of maintaining a mass of 850 grams shall not be difficult since over 200 grams remain after the scientific experiment. 1. Design shall have additional experiment(s) that collects science data and teams must analyze this data. - Additional experiments included the collection of solar energy and determination of light intensity. Our analysis looked at the relationship between the light intensity and current output of the solar panel. 2. Analog sensor inputs shall not exceed 5V. - Analog sensor inputs from the solar cells were a maximum of approximately 2.5V while input from the light intensity sensor was a maximum 4.5V. 3. After flight, BalloonSat shall be turned in working and ready to fly again. - After touchdown, no repairs were needed. The satellite is in working order.

RFP/Proposal/Requirement Compliance Matrix 4. Flight string interface tube shall be a non-metal tube through the center of the BalloonSat and shall be secured to the box so it will not pull through the BalloonSat or interfere with the flight string. - A plastic tube contained the flight string. Holes were drilled to enable a paperclip to slide through to act as a locking device. Care was taken to bend the paper clip to allow the flight string to travel the length of the tube. The gap in the structure to allow the tube through matched the diameter of the tube as closely as possible. 5. Internal temperature of the BalloonSat shall remain above -10˚C during the flight. - The temperature did not go below 2°C inside the BalloonSat. 6. Total weight shall not exceed 850 grams (leaving only 350 grams for structure and experiment). - Total mass of satellite was 856g. (extra was allowed for HOBO)

RFP/Proposal/Requirement Compliance Matrix 7. Each team shall acquire (not necessarily measure) ascent and descent rates of the flight string. - The X and Y accelerometers of the AVR Microcontroller shall determine ascent and descent rates of the flight. 8. Design shall allow for a HOBO H (provided) 68x48x19 mm and 30 grams - The total dimensions for the satellite are x x mm. Within that design there has been a space designed for a HOBO sensor. 9. Design shall allow for external temperature cable (provided) - A hole was made for the cable. 10. Design shall allow for an Canon A570IS Digital Camera (provided) 45x75x90mm and 220 grams (with 2 AA Lithium batteries) - The satellite’s dimensions are x x mm, and designed into that total volume is a space for the Canon Digital Camera.

RFP/Proposal/Requirement Compliance Matrix 11. Design shall allow for AVR microcontroller board and batteries weighing 150 grams including batteries and 20x80x110mm (provided). Dimensions do not including 2 x 9v batteries. -The satellite’s dimensions are x x mm, and designed into that total area is a space for the AVR microcontroller board. 12. Design shall allow for an active heater system weighing 100 grams with batteries and id 10x50x50mm (provided). Dimensions do not include 2 x 9 volt batteries. -The satellite’s dimensions are x x mm, and within that space an area for the heater has been designed. 13. BalloonSat shall be made of foam core (provided). - Foam core was supported by aluminum tape and glue to create a sturdy structure. Each corner shall maintain a seam with the method of cutting two layers at a 45˚ angle. 14. Parts list and budget shall include spare parts. - Quantity of spare parts will be provided in the parts list budget.

RFP/Proposal/Requirement Compliance Matrix 15. All BalloonSats shall have contact information written on the outside along with a US Flag (provided). - Contact information was included and US Flag was proudly be flown. 16. Proposal, design, and other documentation units shall be in metric. - Metric units were be the only units used for proposal, design, and analysis. 17. Launch is in November 7, Time and location: 6:50 AM in Windsor, CO. Launch schedule will be given later. Everyone is expected to show up for launch. Only one team member is required to participate on the recovery. Launch and recovery should be completed by 3:00 PM. - Rides were acquired to the launch site with friends.

RFP/Proposal/Requirement Compliance Matrix 18. No one shall get hurt. - No one was harmed. 19. All hardware is the property of the Gateway to Space program and must be returned in working order end of the semester. - Photon Phinder and all of its hardware shall be immediately returned to the program in proper conditions. 20. All parts shall be ordered and paid by Chris Koehler’s CU Mastercard by appointment to minimize reimbursement paperwork. All teams shall keep detailed budgets on every purchase and receipts shall be turned in within 48 hours of purchase with team name written on the receipt along with a copy of the Gateway order form (HW 04). - Comprehensive budget reports funded by Chris’s Mastercard shall be submitted promptly after order. 21. All purchases made by team individuals shall have receipts and must be submitted within 60 days of purchase or reimbursement will be subject to income taxes. - Receipts were promptly submitted.

Cost Budget Additional expenses

Mass Budget

Message to Next Semester Rule number one: stick with a simple experiment! Our team went with a simple experiment, and the project ended up being enormously time consuming and wrought with problems. A complicated experiment would spell trouble. Furthermore, make sure to continue to stay on top of the work and not leave anything for the last minute. Most importantly, work extremely hard to understand every nut and bolt of the experiment for the proposal. This will keep the team from having to rework the entire circuitry for Rev A/B. For our experiment, the team designed a large structure to maximize the available space to attach insulation to protect the satellite from heat loss. This was a great success since the internal temperature of the balloon satellite never dropped below 2 degrees Centigrade. Furthermore, make sure to use anti-fog because the photos are among the most tangible results from your experiment. However, make sure the camera is extremely secure. Our team was extremely lucky because condensation caused the sticky tape of the Velcro to detach from the insulation. The Velcro finally separated from the foam core on landing; however, if this had happened immediately following burst, the internals would have been ripped to shreds. Most importantly, have fun and keep your chin up because this is your first engineering project and will dramatically help your confidence and experience but only if you keep working to optimize the project.

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