Slide 1Slide 2Slide 3Slide 4Slide 5Pitch ControlRoll ControlYaw ControlSlide 9Slide 10Slide 11Slide 12Slide 13Slide 14Barry BarriosBarry BarriosStructural EngineerStructural EngineerDaniel ChaparroDaniel ChaparroStructural EngineerStructural EngineerLaura GarrityLaura GarrityPropulsionPropulsionChad LiebermanControl SurfacesAdam VaccaroElectrical Engineer/Systems IntegrationCompleted Design ReviewTEAMDesign ObjectiveDesign ObjectiveThe goal of our CDR and the meeting we held between the PDR and CDR was to finalize our design. We aimed at creating a lightweight craft that was maneuverable and quick. To help meet these goals, we lightened the truss system by decreasing supports, and instead of torque arms for steering we are using motor/servo linkages that will rotate and direct the thrust.Pitch ControlPitch ControlA servo will pivot the big A servo will pivot the big motor up or down.motor up or down.Vector thrust from the big Vector thrust from the big motor will raise or lower motor will raise or lower tail of blimp to adjust tail of blimp to adjust altitude.altitude.By Chad LiebermanRoll ControlRoll ControlThe center of mass will lie in the middle of The center of mass will lie in the middle of the bottom of the truss structure so that the the bottom of the truss structure so that the blimp will not naturally roll in either direction blimp will not naturally roll in either direction to achieve equilibrium.to achieve equilibrium.The balloons will be held in a net-like The balloons will be held in a net-like structure and secured to both the top and structure and secured to both the top and bottom of the truss structure to minimize a bottom of the truss structure to minimize a swaying motion that would cause a roll.swaying motion that would cause a roll.Yaw ControlYaw ControlSecond Servo will Second Servo will pivot small motor left pivot small motor left or right.or right.Vector thrust will steer Vector thrust will steer the front of the blimp the front of the blimp left or right to control left or right to control movement about the movement about the lateral axis.lateral axis.By Chad LiebermanSmall MotorBig MotorPropellerReceiverServosReceiver Battery9.6V BatteryBalloonsWood FrameTotal:Quantity112121131Weight90 g210 g5.2 g27 g43 g90 g180 g30 g322 g1205 gAerodynamic AnalysisVehicle WeightAerodynamic AnalysisHelium RequiredLift = (ρair – ρhelium)*g*VHelium Density = 0.174 kg/m3Air Density = 1.25 kg/m3g = gravitational constant 9.81 m/s2V = Volume of helium usedVolume Helium Required = 1.47 m3Volume per balloon = .52 m3(assuming 1.5 kg total weight including payload)Aerodynamic AnalysisEstimated TimeMax Thrust = .95 NMax velocity = T (.5*S*cd)1/2vmax = 0.93 m/sDistance = 87.78 mTimestraight line = 94 sTimetotal = 120 s• Moved motors to a more central location to increase stability of design• Lowered motors below main truss structure to allow more room for them to move and in order to avoid the air movement they create disrupting the balloons paths and stability• Removed large stabilizer in an effort to decrease weight and nonessential partsEvolution of Design• Decided to put battery pack and receiver and all payload possible in one central control systems and payload storage area• Decided that even with extra airflow generated by motor elevator wasn’t guaranteed to work, so removed it• Kept three-balloon-in-a-row design due to required lift and desired maneuverability• Altered truss structure a little to increase strength and decrease weightEvolution of DesignConclusionOur design process has been a series of compromises between strength, weight, speed, maneuverability and feasibility. Our final design sacrifices some structural support in favor of weight, and we use fewer motors than originally planned. We feel the method of control we are using will be more effective and lighter weight than using torque arms. Final adjustments will depend on trials day and how the balloons perform with our