Completed Design Review

1
Completed Design Review

• Team Airblade
• Timothy Davenport
• Brian Guerrero
• Mark Kastantin
• Oscar Kataura
• William Peters
• Robert Taylor

2
Overview

• Structural Changes since PDR
• Description of Finalized Design
• Design analysis Stability and control
• Calculations mass, payload, course completion
  time, etc.
• Timeline

3
Structural Changes since PDR

• Trapezoidal cross-section gtgt triangular
  cross-section
• Sides of craft balsa boards gtgt triangular truss
• Pitch propeller moved further forward

4
Side View
78.74 inches
3.19 in
3.75 in
3.94 in
Stabilizer
Small motor
Large motors with servos
5
Top View
78.74 inches
3.75 in
payload
payload
battery / control
note balloons removed from view
6
Front View
72º
7
Structural Specifics

• Propulsion 1 large propeller at front end, 1
  large propeller at back end
• Pitch 1 small motor at front end
• Triangular truss for slanted sides, ladder design
  for top side
• 2 meters long, 8.5 meters wide.
• Balloons attached at front end, midpoint and back
  end.

8
Materials

• Balsa wood (3/8 inch squares)
• 2 large motors
• 2 large propellers
• 1 small motor
• 1 small propeller
• 2 servos

• 1 battery pack
• 1 radio control module
• 3 balloons with attachments (string)
• wire

1. Balloons and string are not included in mass
   calculations
2. Wire is included in the mass of the other
   equipment

9
Balsa Wood Length

• Each side piece requires 40 pieces (3.75 inches
  each)
• Top piece requires 20 pieces (3.75 inches each)
• 3 pieces run the length of the structure (2 m
  each, or 78.74 inches)

• Length Calculation
•    3.75(40(2)20)(3)78.74
•    611.22 inches

10
Mass Calculation
11
Roll Stability
Balloon lift

• Balloons are tied to bottom beam and top
  crossbars minimizing horizontal pull
• All weight is centered on bottom beam

Battery, radio control mass
Motor, propeller mass
12
Pitch Stability

• Lift distributed evenly
• Small motor provides pitch needed to maintain
  flight

Variable
13
Propulsion
Drag
Motor thrust

• Two large motors running at 9.6V provides
  2(0.79) 1.58 N
• Drag 1.58 N (at steady state)

14
Drag and Velocity
Drag coefficient for a sphere

• This means the blimp should be moving at a fast
  walking speed.

15
Turning
78.74 inches
3.75 in
payload
payload
battery / control
payload
payload
battery / control
Center of mass

• The large motors work in tandem
• Torque (2)(39in)(0.0254 m/in)(0.79 N) 1.57
  N/m

16
Battery Life

• One battery pack providing
• of lifetime
• Time of completion of race track
• Ample lifetime for completion

17
Timeline

• Up to this point we have the truss structure
  complete and have attached the servos
• For the rest of the time
• Monday Tuesday Wednesday
  Thursday Friday Saturday Sunday
• Week 1
  Attach motors to structure
• Week 2 Complete Wiring Attach
  Balloons Test Fly and
• Week 3 Optimize Trials

18
Conclusion

• So far the project has proceeded smoothly
• Anticipate weight problems that will be fixed by
  sanding the structure
• We feel we have a strong structure with great
  turning potential
• Ready to finish building and get flying