Team Weatherman Completed Design ReviewObjectiveIntroduction to Final DesignScale DrawingsSlide 5Slide 6Control SystemsAerodynamic AnalysisSlide 9Slide 10Design Evolution and AnalysisSlide 12Slide 13ConclusionTeam WeathermanCompleted Design ReviewJames Banks, James Banks, Test EngineerTest Engineer Katonio Butler, Katonio Butler, Electrical SpecialistElectrical Specialist Alex Cutting, Alex Cutting, Structural EngineerStructural Engineer Lori Huberman, Lori Huberman, Aerodynamic Design EngineerAerodynamic Design Engineer Cassandra Roth, Cassandra Roth, Computer Design SpecialistComputer Design SpecialistObjectiveObjectiveTo design a lighter-than-air vehicle that To design a lighter-than-air vehicle that not only meets all design not only meets all design requirements, but is also original and requirements, but is also original and as light as possible, using a cyclical as light as possible, using a cyclical design process.design process.Introduction to Final DesignIntroduction to Final DesignWe decided that the decisive We decided that the decisive factor in the LTA design is the factor in the LTA design is the amount of drag created. We amount of drag created. We opted not to pursue the one opted not to pursue the one balloon design due to its lack balloon design due to its lack of stability. The triangular of stability. The triangular three balloon design was three balloon design was eliminated because of the eliminated because of the extreme amount of drag and extreme amount of drag and the weight of the truss that the weight of the truss that would be required. We chose would be required. We chose the in-line, four balloon, airfoil-the in-line, four balloon, airfoil-like design due to its low drag like design due to its low drag and creativity, with the single and creativity, with the single motor mounted in the front, motor mounted in the front, which controls the pitch and which controls the pitch and yaw of the LTA.yaw of the LTA.Scale DrawingsScale Drawings•Bottom:Bottom:Scale DrawingsScale Drawings•Front:Front:Scale DrawingsScale Drawings•Side:Side:Control SystemsControl SystemsThe shape of our LTA The shape of our LTA vehicle utilizes drag to vehicle utilizes drag to stabilize the vehicle when stabilize the vehicle when in motion. We eliminated in motion. We eliminated control surfaces to simplify control surfaces to simplify the vehicle because of this. the vehicle because of this. Our large single motor has Our large single motor has a range of 60a range of 60oo both both vertically and horizontally vertically and horizontally to control pitch and yaw. to control pitch and yaw. Also instrumental in our Also instrumental in our decision was that the decision was that the vehicle can be controlled vehicle can be controlled even at low speeds.even at low speeds.Aerodynamic AnalysisAerodynamic AnalysisVEHICLE WEIGHTVEHICLE WEIGHTQuantityQuantityWeight (kg)Weight (kg)EngineEngine11.21.21Engine BatteriesEngine Batteries66.05.05PropellerPropeller11.0052.0052ReceiverReceiver11.027.027ServosServos22.043.043Receiver BatteryReceiver Battery11.094.094Structural FrameStructural Frame11.077.077Mylar SheafMylar Sheaf11.024.024BalloonsBalloons44.07.07Total: Total: 1.10 kg1.10 kgTotal without balloons:Total without balloons:0.823 kg0.823 kgAerodynamic AnalysisAerodynamic AnalysisV=W/(pV=W/(pairair-p-pHeHe)g=1.05m)g=1.05m33This corresponds to 10.78N of lift This corresponds to 10.78N of lift needed.needed.L=(pL=(pairair-p-pHeHe)gV=16.1N)gV=16.1NAerodynamic AnalysisAerodynamic AnalysisThrust – one large engine (9V)=1.3NThrust – one large engine (9V)=1.3NVelocity=T/(.5ScVelocity=T/(.5Scdd))1/21/2=2.91m/s=2.91m/sDrag=.5pDrag=.5pairairvv22ccdd=1.03N=1.03NDesign Evolution and Design Evolution and AnalysisAnalysisRelative Importance of Various Design Relative Importance of Various Design SpecificationsSpecificationsMuch of the early portion of the design process was spent debating Much of the early portion of the design process was spent debating what design specifications were most important. Half of the group what design specifications were most important. Half of the group felt that the aerodynamics were most important, while the other felt that the aerodynamics were most important, while the other half felt that the weight was most important. The group that half felt that the weight was most important. The group that tended toward decreasing the amount of drag felt that drag would tended toward decreasing the amount of drag felt that drag would significantly slow the vehicle down, thus rendering the vehicle non-significantly slow the vehicle down, thus rendering the vehicle non-competitive. The group that felt that weight was most important, competitive. The group that felt that weight was most important, felt that the heavier the vehicle was, the less payload we could felt that the heavier the vehicle was, the less payload we could have, thus also rendering the vehicle non-competitive. We quickly have, thus also rendering the vehicle non-competitive. We quickly realized that we need to take both ideas under consideration and realized that we need to take both ideas under consideration and made a design that is very light, but still aerodynamic.made a design that is very light, but still aerodynamic.Design Evolution and Design Evolution and AnalysisAnalysisMotor ControlMotor ControlWe decided that the motor should definitely go in the front of We decided that the motor should definitely go in the front of the vehicle, but there was much debate over how many motors the vehicle, but there was much debate over how many motors there should be and how they should be used to control the there should be and how they should be used to control the vehicle. Some people felt that there should be multiple motors vehicle. Some people felt that there should be multiple motors to generate greater thrust. This was eliminated to decrease the to generate greater thrust. This was eliminated to decrease the amount of weight. Other people wanted to go with a one motor amount of weight. Other people wanted to go with a one motor design, but simply use the motor to generate thrust and use design, but simply use the motor to generate thrust and use control surfaces for stability.