Patrick O’Brien, Sara Monacelli, Tiffany Monroe, Madison Wiebe, Andy Broucek, Jacob Haynes 11/30/09

 The mission of Team S³ is to analyze the performance of multiple types of solar cells at various altitudes between launch altitude and approximately 30 km. This test will examine power output as a measure of performance and will allow the team to better understand solar cells—possibly improving solar cell usage.  We expected the monocrystalline would work better than polycrystalline because there is a gap between the layers in a polycrystalline cell and we thought this would make the cell more inefficient because some of the heat may be lost in this gap between the layers.

 Solar panels  Batteries  AVR  Multiplexer

 The light to frequency converter was changed into photodiodes.  We completely got ride of the solderable perf- board.  We also changed where we placed everything in the BalloonSat.

 Predicted  The monocrystalline was predicted to be more efficient that the polycrystalline.  Both were predicted to be more efficient in the air than on the ground because the sun will be more intense.

 Actual Results  Both were much more efficient at higher altitudes.  Monocrystalline  Averaged.006 volt on ground  Lowest average in air was.01 volt  Polycrystalline  Averaged.067 volts on ground  Lowest average in the air was over.83  Two Major Reasons  Temperature  Light intensity  Unable to tell which was more efficient at higher altitudes  Poly went over voltage due to much higher efficiency

 The flight went well with the monocrystalline, but polycrystalline maxed out the AVR for most of the flight.  Data was great from all of the other sensors  Photodiodes gave similar results as solar panels  Wanted it to test sunlight independently of other factors, but it didn’t.

 Our camera and HOBO failed. There is no way to know why the HOBO failed. However, our camera failed because one of our group members accidentally used a different piece of insulation to insulate the lens, than we tested. It applied too much pressure on the lens, which caused the camera to shut off. The lens was so tight in its hole that we didn’t know it shut off before flight even began. We were able to repeat the this and verify that this was truly what caused this failure. For future flights we will use the thinner insulation and make it of a smaller width.  Also, we used four wrong resistors for the polycrystilline solar cells. We used too low of resistance. This caused the voltage reading to be above five volts, which was the maximum for the AVR. During testing, we could not tell this because it did not need to go above five volts at ground level. This failure only occurs at a very high altitude. We have found a new resistor that has a higher resistance to rectify this problem.

 Solar cells are more efficient in space than they are on earth. We partially attribute this to the colder temperatures at near space.  Our data showed a rapid increase in voltage as the BalloonSat increased in altitude.  Space Based Solar Power is a more efficient use of solar cells.

 Our BalloonSat should be stored in a closed, room temperature environment.  A few minor changes need to be made in order for our BalloonSat to be ready to be flown again. We need to make sure that the piece of foam core is thinner so that it doesn’t disrupt the lens. We would also need to make sure that we have a resistor that has a higher resistance so that we can read our data from the solar cells easier.  If our BalloonSat should be flown again, the payload would need to be rearmed, and the switched need to be flipped, bottom and then top.

 If we were to have done this again, we would test the insulation we put around the camera more thoroughly.  We would also make our meetings more efficient.

 Message to next semester (show but only discuss if time)  Everything in this class takes about five times as long as you think it will and if you’re as thick skulled as we are, you never learn that this is the case so you sit through multiple 5 hour meetings because you’re an idiot.  Teamwork is important. It gets things done.  Even if you could get something done faster on your own, you have to be willing to participate in the group process.  THERE IS A REASON FOR TESTING!!!  Test all of your components before your flight– not following this advice may cause a malfunction.  Write Apendicies from now.  Don’t listen to Jacob  JENNIFER AND CHRIS GRADE COMPLETELY DIFFERENTLY. KNOW WHO’S GRADING YOUR WORK BECAUSE THE GRADER SIGNIFICANTLY IMPACTS YOUR GRADE. GRADE!  Remember, dayquill takes out the drowsies and don’t get your smashers fingered.  Your teammates are all fun and dandy, but don’t trust them because in the end, they’ll all turn on you.  Some kids don’t deserve talking privlidges.  You are the chosen one.  Never eat soggy waffles.  Unless they’re soggy because there’s too much syrup. That’s entirely different, but I’m not really sure if something can be soggy in syrup anyway, so actually, disregard everything I just said.  Exlcuding, of course, what I said before I started talking about waffles. That will be useful to you next year.  Not to say that knowledge on waffles won’t be, but it doesn’t pertain to the class as much as the other sutff does.  At least that’s the case right now, maybe that won’t be so next year, so actually read all of this.  Czeck Sphelling.  Chocolate Chip is the best type of Snackimal  Sometimes meetings take too long.  Sabotage your team, you’ll never see them again.  I was an aerospace major before I came into this class.  Yin and Yang are intricately bound in this world.  Jacob still has Andy’s Camera  ~ <3, Patrick