Apollo 18Final Presentation

Maggie WilliamsPeter MerrickCody Gondek

Nathan Buzzell

Chris DavidoffJacob Hermann

Jared LevinLindsey Buxman

12/11/12

Mission Overview• Our mission was to calculate the speed of

sound as our satellite rose to 30 km.• We expected the speed of sound to

change in relation to the temperature and pressure changes.

• We predicted that temperature would influence the speed of sound the most.

• This data could be useful for high-altitude aircraft.

Design OverviewBottom box

o Critical systems

• Camera

• Micro controllers

• Heater

• Sensorso Microphoneo Temperatureo g-forceo Humidityo Pressure

Top boxo Speakerso Heater

Final Adjustments

•Removed RF links, unnecessary

•Filtered the code to exact frequency the speakers emit, to reduce recorded errors

Functional Block

Diagram

Results and Analysis

Accelerometer

Percent Humidity

Pressure

Temperature

Recorded experimental Data

Speed of Sound calculated from collected data

Predicted Results

Speed Data and Temperature

Data Before Gap

Data After Gap

Failure Analysis

• Microphone stopped collecting data• Using GoPro video, we determined

that the speakers continued to work during flight

• Gap in the data from when the satellite entered the stratosphere to when the string was cut.

Speed Data and Temperature

Pressure and Data

Change in PressureThe point at which the microphone ceased to collect data was when the pressure was at it's lowest point (under 2.2 psi)

Decreased pressure also decreases the volume of the speakers

To fix this for future flights, we adjusted the filtering in the coding of the microphone to collect a wider range of data

Phet SimulationPressure Relation to Volume

Preflight Data

Conclusions• We found that as temperature decreases the

speed of sound decreases.• We also found that pressure is a large factor

in sound travel.• An apparatus with the two separate modules

can measure the speed of sound in the atmosphere.

• We discovered that carbon fiber tubes are a lightweight and decent cost solution for a strong yet flexible structure.

• Microphoneo Capabilities, Insulation

• Batteries

• SD Cards

• Speaker Threshold

Ready to Fly Again

Lessons Learned

• Test the mission experiment more thoroughly• A stiffer structure may be beneficial• A louder speaker is a MUST

• Try and make your experiment fail during testing

• Time management• Working with a team

Requirement Compliance

• Reached 99,430 ft.• S.O.S.-(G)-325 m/s (A)-279.15 m/s• Internal temp.- -10 Celcius• Spent- $121.78• weight- 1110g

Budget and Final Mass

Messages To Next Semester

• Utilize the skills of every team member• Stay organized• Communicate• Stay positive• Be passionate about your idea and

making it work