Lighter Than Air Critical Design Review

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Lighter Than AirCritical Design Review
The A-Team

• Mark Cote
• Yonas Tesfaye
• Josh Levinger
• Bryan Owens

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Presentation Objectives

• Introduce Final Design
• Scale drawings of final design
• Control systems of final design
• Aerodynamic analysis of final design
• Final design evolution and analysis

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Final Design

• Linear
• Pros
• Reliable and well tested
• Low drag profile
• Stability
• Simplicity
• Expandable
• Cons
• Difficult to maneuver
• Large structure requirement
• Unwieldy (N-body problem)

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Scale Drawings
Front View
Courtesy Mark Cote
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Scale Drawings
Side View
Courtesy Mark Cote
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Scale Drawings
Bottom View
Courtesy Mark Cote
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Control Systems
We will be using two servos to steer. The motors
are in line and the front motor will be used to
steer left and right. The rear motor will be
used to control pitch. We will also have rear
stabilizers.
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Circuit Diagram
Courtesy Josh Levinger
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Materials

• Object Quantity Mass (g)
• Large Motor 2 420.0
• Propellers 2 15.9
• Receivers 1 27.0
• Servos 1 43.0
• Battery pack 1 148.0
• Balloons 3 210.0
• Structure 1 175.0
• Total Weight 1040 g
• Total Payload 710 g

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Aerodynamic Analysis
1.773 m3 1 balloon .524 m3 3 balloons
overfilled should support the weight.
Lift generated by three normal balloons 15.205
N Overfilling Balloons 17.150 N
We believe that we will average 2/3 of the
maximum thrust throughout the course for a
velocity of 2.09 m/s.
We believe our blimp will be able to complete the
course in 42 seconds.
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Final Design Evolution and Analysis

• Originally, we had decided on a triangle design
  with differential steering. Our first concern
  was in regards to drag because it had profile
  drag of about two balloons as which meant we
  would be fighting twice as much drag.

Top View
Front View
Courtesy Mark Cote
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Analysis Contd

• We also realized that with differential steering,
  we would lose a significant amount of thrust.

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Good Luck to all the Teams!!!