University of Colorado 2005 Design, Build, Fly Team

1
University of Colorado2005 Design, Build, Fly
Team

• Preliminary Design Review

2
Purpose

• The purpose of DBF is to enrich engineering
  students of all disciplines and levels in the
  adventure of Designing, Building, and Flying a
  unique and original remotely controlled airplane.
  
• Learning the Engineering Process
• Learning aerospace concepts
• Hands on experience

3
Management Structure

• Team Leads
• Sub-Groups
• Mission Analysis
• Aerodynamics
• Structures
• Propulsion
• Group Interaction

4
Competition

• Hosted by AIAA and Cessna
• April 22-24
• St. Inigoes, Maryland
• Sensor Reposition
• Internal and External
• Payloads
• Ground Handling
• Five Scoring Flights
• SCORE Written Report Score Total Flight
  Score Rated Aircraft Cost

5
Budget

• Applying for UROP and EEF funding
• Approximately 4000 will cover all building
  expenses

6
Mission Team

• Team Lead Spencer Riggs

7
Mission Description

• External Drop Mission
• Payloads mounted not more than 3 from wingtips.
• Aircraft takes off, completes one lap, lands
• Taxi to first drop area, drop one payload
• Taxi to second drop area, drop other payload
• Both payloads must be remotely dropped from wings
• Take off, complete one lap, land
• Disassemble aircraft and return to its storage
  box (storage box is 4x2x1)

8
Mission Description, cont.

• Internal Drop Mission
• Payloads are enclosed inside fuselage
• Flight profile is the same as the external drop
  mission.
• Internal mission payloads are the same as the
  external mission payloads, no modifications
  between flights are allowed.
• Internal payloads may be removed by hand.

9
Flight Pattern for Competition

• This picture is the flight pattern that all teams
  must follow. Note the 360 degree turn in the
  middle of the track. The drop zones are before
  the starting line shown on the map.

10
Payload System Design

• The payload has a simple latch release system
  operated by a servo that releases the external
  payload. This latch design is also used for the
  internal payload.
• The payload is a 12 long, 3 internal diameter
  PVC pipe. Each payload must weigh 3 lbs.
  Aerodynamic features such as nosecones can be
  added, however the regulation length does not
  include these aerodynamic features.

11
Weather for Competition

• For the competition, which is at the end of
  April, weather conditions for the Baltimore area
  are
• Temps HighHigh 60s F LowHigh 40s F
• Precipitation 3-4 inches average
• Snowfall Trace to none (still possible though)
• Humidity 50-75 throughout the day
• Winds 10 mph WNW
• Medium Cloud Cover on average
• Overall Cool, cloudy, wet, HUMID

12
Aerodynamics Team

• Team Lead Terry Song

13
Aerodynamics Trade Study

• Aerodynamic configuration
• Wing configuration
• Empennage configuration
• Aircraft configuration
• Deciding category
• Rated Aircraft Cost
• Flight performance
• Weight
• Mission Profile

14
Wing Configuration

• Elliptical wing
• Most aerodynamically efficient
• Very suited for long distance, heavy payload
  flight

• Trapezoidal wing
• Closely resembles the lift performance of an
  elliptical wing
• Requires a specific root to tip ratio

15
Wing Configuration

• Rectangular wing
• Ease of construction
• High experience level
• More suited for the mission requirements

16
Wing Configuration Trade Table
17
Empennage Configuration

• Conventional
• High experience level
• Suitable for many types of aircraft
• T-tail
• More efficient
• Smaller horizontal control surface

18
Empennage Configuration

• Cruciform
• Compromise between Conventional and T-tail
• Relatively efficient
• V-tail
• Less control surfaces
• Smaller rated aircraft cost
• Easy fitting inside the box

19
Empennage ConfigurationTrade Table
20
Aircraft Configuration

• Twin boom
• Enables pushing propeller
• Canard
• Good maneuverability
• Good stall characteristics

21
Aircraft Configuration

• Flying Wing
• Good drag efficiency
• Conventional
• High experience level
• Ease of construction

22
Aircraft Configuration Trade Table
23
Structures Team

• Team Lead Matthew Osborn

24
Fuselage and Wing Construction Method Factors

• Time
• Limited time for construction.
• Experience
• Effects quality and time.
• Weight to Strength
• Weight effect RAC
• Payload Integration
• Overall mission requires internal payload.
• Reproducibility
• Testing and mistakes

25
Backbone

• Pros
• Lightweight
• Strong
• Design Simplicity
• Cons
• Internal Payload Integration
• Hard to Reproduce
• Labor and Time Intensive

26
Balsa Stringers

• Pros
• Lightweight
• Allows for Contours
• Simple Construction for Contours
• Cons
• Multiple Parts
• Payload Integration
• Reproducibility

27
Balsa Structure

• Pros
• Extremely Lightweight
• Simple Construction
• Reproducible
• Payload Integration
• Cons
• Design Limitations
• Strength

28
Monocoque

• Pros
• High Weight to Strength Ratio
• Reproducible
• Can Design to the Payload
• Cons
• Labor and Time Intensive
• Expensive
• Lack of Experience

29
Fuselage Construction Methods
30
Foam and Composite

• Pros
• Strong
• Least Labor Intensive for Composites
• Cons
• Heavy
• Experience with Composites

31
Composite Built Up

• Pros
• Strong
• Cons
• Heavy
• Labor Intensive
• Experience with Composites

32
Monocoque

• Pros
• Weight to Strength
• Reproducibility
• Cons
• Heavy
• Experience with Composites
• Labor and Time Intensive

33
Balsa Structure

• Pros
• Lightweight
• Reproducibility
• Simple Construction
• Cons
• Weak

34
Foam and Balsa

• Pros
• Lightweight
• Strong
• Simple Construction
• Reproducible
• Cons

35
Wing Construction Methods
36
Effects of Payload on the Wing
37
Landing Gear Factors

• Payload Drop
• Landing gear must not interfere with payload drop
• Ground Maneuverability
• Missions require much taxiing.
• Takeoff and Landing Characteristics
• Must land to win.

38
Landing Gear
39
Propulsion Team

• Team Lead Grant Bovee

40
Brushed or Brushless

• Using Motocalc with given constants
• W/S
• Prop Size
• Battery Power
• Estimated Weight
• Found brushless to be superior
• More Efficient
• Less Weight
• Less Adjustments

41
Motor/Battery Configurations
42
Battery Type

• NiCad or NiMH

43
Size of Motor

• Small but meets Requirements
• Take off distance
• Lap time
• Depends on structural design
• Wing loading
• Weight
• Optimal size
• Between 40 and 60

44
Possible Designs Pursued
45
Skinned Cat

• Light Weight
• Balsa not composite
• Simple
• Tail Dragger Configuration

46
Tail Dragger

• Tail Dragger Configuration
• Monocoque Construction
• Great weight to strength ratio
• Fits in the box

47
Tricycle

• Same construction techniques as tail dragger
• Good ground handling
• Too tall to fit in box in one piece
• Heavy Landing Gear

48
THANK YOU

• Having all of you take an interest in our small
  extracurricular group is very appreciated.
• Questions?
• Comments?
• Suggestions?