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CDR_Team_03 Powered By Docstoc
					      Skillz That Killz
        Critical Design Review
Jocelyn Mulkey, Jess Davidoff, Kaitlyn
Zimmitti, Taylor Smith, Travis Dowdy,
           Hunter Hoopes
           October 8, 2009
Mission Overview
 To investigate both the benefits and cost s of generating energy with solar at
  high altitudes
 Solar cells use photons as light energy to create electricity
 We would like to determine if encapsulated monocrystalline solar cells
  generate more electricity at higher altitudes as a result of clearer and more
  intense light
 Purpose of Our Experiment:
     Answer the question: Could solar cells replace batteries in future
     BalloonSat missions?
    If this is true, future BalloonSat missions may not be constrained by battery
     life, weight and volume
 Our results may also increase knowledge about solar energy
    Could help answer the question: Is installing solar panels to airplanes to
     power them a feasible solution to reducing their carbon footprints?
          Requirements Flowdown
•   Goal (G1)‫‏‬
     – Our BalloonSat shall rise to an altitude of roughly 30 kilometers in order
       to perform a scientific experiment that will measure the energy output of
       solar cells at altitudes higher than ground level so as to better
       understand the ability of these cells to generate more electricity at
       higher altitudes as a result of clearer and more intense light.
•   O1 (comes from G1)‫‏‬
     – Assemble BalloonSat in order to advance our understanding of solar
       energy at an altitude of 30 kilometers for under $100 by 11/07/2009.
•   O2 (comes from G1)‫‏‬
     – Determine altitude by measuring tilt in one axis.
•   O3 (comes from G1)‫‏‬
     – Establish a function of altitude to find the correlation between altitude
       and solar energy.
 Level 0 Require ments
0.Obj1 The team shall construct the BalloonSat and complete testing by                 O1
         10/29/09. Testing shall occur in appropriate locations as the BalloonSat is
         being built to ensure each system is in working order, and construction of
         the BalloonSat shall cost under $100. Testing and construction shall last
         for approximately 24 days.
0.Obj2 After flight, altitude shall be determined using the data from the
0.Obj2 After flight, altitude shall be determined using the data from the              O2
         accelerometer. The data retrieval and analysis shall take 20 days
         maximum and shall occur in the Discovery Learning Center.
0.Obj3 After flight, solar energy shall be measured as a function of altitude using    O3
       the data from the accelerometer (0.Obj2) and the data from the solar cells.
       This analysis shall take less than 20 days and will also occur in the
       Discovery Learning Center.

Level 1 Require ments
1.Sys1 All aspects of the BalloonSat system shall be compatible and have the           O1
        capability to function correctly with each other.
1.Sys2 The BalloonSat system shall establish the tilt from 10 to -10 degrees with      O2
        a precision 0.5 degrees, with a goal of 0.1 degrees.
1.Sys3 The BalloonSat system shall determine the voltage from each solar cell          O3
        and record the data on the AVR Microcontroller in volts.
 Structural Design
    17 centimeter cube
    Double-layer foam core, secured with hot glue, aluminum tape, and Velcro, if necessary
    We will have a small Plexiglas window on one side to protect the camera's lens during flight.
    We will have a solar cell on each side of the cube placed into an inset in the foam core
         The solar cells are monocrystalline and encapsulated (no further protection needed from
Hardware Design

    Six solar cells will be connected to an 8-input multiplexer inside the cube, which will direct the
analog input from each cell to one input on the AVR Microcontroller board.
         The multiplexer is necessary because we only have four available inputs on the AVR, but six
          solar cells from which to collect data.
         The AVR will record the voltage from each solar cell. Because the AVR records data in volts,
          and the solar cells output in volts, there will be no need to convert the data after retrieval
          other than with the Data Parser Utility. When we are retrieving our data, we will use the
          utility to convert the data from binary to voltages.
        Other hardware pieces
              AVR Microcontroller board (to record data from temperature, altitude, air pressure, and voltage
               from solar cells)‫‏‬
              Heater system (temperature control to protect hardware)‫‏‬
              Digital camera (to record pictures from the flight)‫‏‬
              Multiplexer (to take the voltage inputs from all 6 solar panels and channel them into one input
               on the AVR)‫‏‬
              Four 9V batteries, foam core, Velcro, hot glue, insulation, a non-metal flight string tube, extra
               wire, MUX, test batteries, and dry ice.
              (All of these materials are provided or are in the SpaceGrant inventory except for the solar cells
               and the MUX, which will be purchased from Sundance Solar and West Florida Components,
               and the test batteries and dry ice, which will be paid for by our team and purchased from
               Safeway. )‫‏‬
   Experimental Design
        The reason for placing a solar cell on the four sides of the cube is to ensure there is always light
         reaching at least one cell.
        The bottom cell
                  – May collect photons reflected from the ground (especially if snow is present), and, when
                    high enough, reflected from the clouds
                  – We will draw conclusions from our data if this is true.
Design Sketches
Cube – 17 × 17 × 17 cm
9V Batteries (4) – 19.2 × 10 × 6 cm
AVR Microcontroller – 2 × 8 × 11 cm
Canon Digital Camera – 4.5 × 7.5 × 9 cm
Heater System – 1× 5 × 5 cm
HOBO – 6.8 × 4.8 × 1.9 cm
Functional Block Diagram
Item                          Where to get it           Cost                         Wight
AVR Microcontroller and       Provided                  $0                           150 g
Heater system and             Provided                  $0                           100 g
Foam Core                     Provided                  $0                           108 g
Insulation                    Provided                  $0                           TBD
Switches                      Provided                  $0                           20g
Flight String Tube            Provided                  $0                           TBD
Canon Digital Camera          Provided                  $0                           220 g
Monocrystalline Solar Cells   Sundance Solar            $69.40                       42 g (6 cells)

8-Input Multiplexer           West Florida Components   $26.78                       TBD
Plexiglas (9x7.5 cm)          Space Grant Inventory     $0                           64 g
Resistors (if needed)         SGI                       $0                           Not required at this time
Velcro                        SGI                       $0                           Not required at this time
Aluminum Tape                 SGI                       $0                           <1 g
Hot Glue                      SGI                       $0                           16 g
Extra Wire                    SGI                       $0                           Not required at this time
Test Batteries and Dry Ice    Safeway                   Approx $35 (cost covered     N/A
                                                        by team)
                              TOTAL                     $96.18 (not including cost   Total of Known: 721 g
                                                        covered by team)             Weight allowed for
                                                                                     unknowns: 129 g
                                         Project Schedule

Team Meetings:                               All Tuesdays at 2:00 p.m.
Design complete                              9/20/09
Complete Proposal                            9/15/09
Proposal Due                                 9/17/09 6 p.m.
Conceptual design review                     9/ 22/09 8 a.m.
Program AVR                                  9/27/09
Order all hardware                           9/29/09
Foam Core Structure Built                    0/05/09
Critical design review                       10/06/09 8 a.m.
DD Rev A/B due                               10/06/09
Structure Testing – Drop/Whip Tests          10/06/09 2 p.m.
Prototyping design complete                  10/13/09
Experiment Testing                           10/14/09
Subsystem Testing (Heater/Solar Cells)       10/14/09
Testing final design complete                10/20/09
Cold Test                                    10/20/09
Functional Test – Heater, Camera             10/20/09
Camera/Imaging Test                          10/20/09
Subsystem Test                               10/20/09
Pre-Launch Inspection (Bring hardware)       10/27/09
Mission simulation tests (bring B.Sat)       10/29/09
Launch Readiness Review                      11/03/09 8 a.m.
DD Rev C due                                 11/03/09 8 a.m.
BalloonSat Weigh-in and Turn in              11/06/09 2 p.m.
DLC 270 A and FRR Cards Due                  11/06/09
Launch Day!!!                                11/07/09 4:45 a.m.
                         Test                              Plans

Experimental Testing            •Place BalloonSat in sun for same amount of time as
                                •Rotate B.Sat to simulate spin during flight
                                •Record voltage input from solar cells and temperature

    Test Plans                  (to test temp effects on cells)
                                •Retrieve and analyze data from cells and temp sensor
                                •Make sure input from solar cells does not exceed 5V
                                limit and install resistors if needed

Structural Testing              •   Whip test (determine force of flight will not destroy
                                    or weaken structure)
                                •   Drop test (determine burst/landing will not destroy
                                      •   4-story drop + kick down stairs
                                •   Cold Test (placed in a cooler of dry ice for ~2 hours
                                    to simulate temperatures during flight)
Functional/Subsystem Testing    •Test correctness of software codes
                                •Test camera’s ability to turn on
                                •Test heater’s ability to keep B.Sat above (-10°c) for ~2
                                •Test all subsystems work together and that power
                                input/output does not exceed 5V
Mission Simulation Testing      In class mission simulation

Camera/Imaging Testing          Test camera to ensure
                                •Images/videos are being recorded
                                •Images/videos are clear
                                •Determine if Plexiglas obstructs images
                     Test      Completion Date

Experiment Testing                               10/14/2009

Structural Testing                                10/6/2009

Functional/Subsystem Testing                     10/20/2009

Mission Simulation Testing                       10/29/2009

Camera/Imaging Testing                           10/20/2009
Expected Results
The purpose of our mission is to determine the advantages of generating energy
  with solar cells at altitudes other than ground level. We hope to discover if solar
  cells are more beneficial when at higher altitudes.
 Expected Results: To either show increased energy as altitude increases or
  show negligible difference in energy input.
 To retrieve data: Connect AVR board with data to computer and use Data
  Retrieval Utility to retrieve data from board.
 To read data: Use Data Parser Uttility to transform data from binary to
  voltages which we can use to analyze data
 To organize data: Use Excel where we can then interpret and draw conclusions.
   These graphs indicate what our data for the four side cells should look like, whether the payload is
    spinning, if it is stationary, or a combination of the two circumstances. The data from the top and
    bottom cells will not be affected by spin so they are not included in the graphs.
   If the payload rotates, each reading should provide about the same average voltage reading over the
    course of the flight:

   If the payload starts rotating and ends in a static condition, we should see several of the cell's data
    drop-off and only one or two cells producing current:

   If there is no or minimal rotation we should only see in the data two cells providing current:

   The data of the voltages of each solar cell will allow us to determine which solar cell was facing the sun
    (or snow, for the bottom cell) at what time. The voltage data of the cell facing the sun will be higher
    than the others. This will help us to visualize the attitude of the satellite throughout the flight.
   In order to determine altitude from the air pressure data, we will use the equation
                         p =101325 (1 - 2.25577 10-5 h) 5.25588 where p = air pressure (Pa) and h = height above
    sea level (m).
     Team Organization
    Team Member               Title         Secondary Title       Additional Responsibilities

Jocelyn Mulkey     Programming/        Science                Functional Testing
                   Schedule                                   Mission Simulation Testing

Jess Davidoff      Power/              Budget/Reporting       Camera Testing
                   Team Leader                                Presentations
Kaitlyn Zimmitti   Budget              Software               Mission Simulation Testing
                                                              Hardware Ordering/Budget
                                                              Experiment Testing
Taylor Smith       Structure Design/   Power                  Functional Testing
                   Testing Leader                             Satellite Recovery
                                                              Design Documents
Travis Dowdy       Science             Programming            Experiment Testing
                                                              Camera Testing
                                                              Data Analysis
Hunter Hoopes      Software            Structure Design       Functional Testing
                                                              Data Recovery
                                                              Block Diagram
Biggest Worries
 Flight weather conditions
 Voltage input from cells
  over 5V
 Effects of temperature on
  solar cells

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