Handheld Spy Chopper

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Handheld Spy Chopper
Group 10 Chris Alexander Bryant
Barrenechea Wilther J. Merchan Shrirag Nair Jason
Ng David Wang
Published by Popular Science
Stevens Institute of Technology Dec 16th, 2008 E
130
2
Last Years Design

• Counter-rotating rotor blades
• Protective outer casing
• Small and portable
• Max Diameter 18
• Max Height 8
• Used fiberglass for body
• Used two motors and two 3-cell batteries

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Issues with Last Years Design

• Restricted airflow-shell design
• Weight-roughly 3 lbs
• Similar RC helicopters with that motor weigh lt 1
  lbs.
• Uniform Design
• Landing
• Lifting off
• Not enough thrust
• Controlling direction

4
Design Matrix
5
Phase I-III Concepts
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Concept Matrix
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Preliminary Design
Top View
Isometric View
Side View
Front View
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Final Design
Top View
Isometric View
Side View
Front View
9
Design Interface
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E-Flite 2.4GHz Controller

• 2.4 GHz DSM radio control
• Spektrum Technology removes interference
• 5 channel transmitter
• Monitors battery power

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Ascending/Descending
Climb
Throttle Trim
Descend
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Rudder Trim/Yaw
Nose Yaws Right
Rudder Trim
Nose Yaws Left
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Elevator Trim/Aileron roll
Elevator Trim
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Horizontal Movement/Aileron Trim
Aileron Trim
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4-in-1 Control Unit

• Main Proportional Mix Trimmer Pot
• Amount of mixing between motors
• Fine tune rudder trim
• Fine tune throttle response
• Adjust gyro gain trimmer
• Adjust aileron trim
• Allows crystal clear frequency transmission of
  DSM controller

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Calculations - Lift
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Calculations - Thrust
Momentum Theory is applied to calculate the
expected thrust from the system.
? density of air R rotor blade radius v
induced velocity T Thrust P Power required
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Motor Alternatives
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Battery Past and Present

• Past
• Flight Power Lithium Polymer (LiPo) 11.1 V,
  800mAh x 2
• Cost 33.99 each (67.98 total)
• 2.50 oz x 2 (5.00 oz total)
• 3.77 x 0.94 x 0.47
• 15 minutes flight time
• Present
• E-Flite LiPo 7.4V, 900mAh
• Cost 29.99
• 1.72 oz
• Size 2.7 x 1.18 x 0.573
• 15 minutes flight time

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Camera

• SPECIFICATIONS
• Camera and transmitter weight only 9 grams!
• Camera and transmitter size 15mm x 22mm x 32mm
  (5/8" x 7/8" x 1 1/4")
• Camera Lux lt3 _at_ f1.2
• Camera Auto Electronic Exposure of 1/60 to
  1/15000 sec. w/ Auto Gain White Balance
• Camera Signal to Noise Ratio gt48dB
• 365K (PAL) or 250K (NTSC) camera pixel resolution
  
• Wireless Transmission Range 150M (450 Feet),
  Line-Of-Sight
• Transmitter RF Output Power EC RTTE Compliant
• Receiver Video Input/Output 1Vp-p/75 ohm

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Camera (power)

• Hardwired
• Pros
• Rechargeable
• No additional weight
• Cons
• Reduce flight time lt 15 minutes
• Supplemental Power Source
• Pros
• Increased flight time gt 15 minutes
• Cons
• Additional weight (1.47oz)
• Non rechargeable
• Maintenance (to replace battery)

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Material Foam
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Camera Placement
Front View
Isometric View
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Swash Plate

• Known as cyclic pitch
• Allows the helicopter rotor to provide selective
  lift in any direction
• One fixed plate (bottom plate)
• Connected to 2 oscillating servos
• Adjusts the orientation of top plate
• Rotating Plate
• Connector to rotor
• Transfers the fixed plate changes to the
  propellers

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Make or Buy Matrix
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Current Budget
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Last years Budget

• Current year budget 343.83
• Reduced cost for all major parts
• Engine 44 -gt 15
• Radio Controller 170 -gt 60

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Current Weight
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Last years Weight

• Current year Weight 8.95 oz
• Reduce weight of major parts
• Shell 15 -gt 1.4
• Battery 5 -gt 1.5
• Rotor Head 3.6 -gt 0.2

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Battery Support
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Battery Bracket
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Landing Platform
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Final Design Drawing
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Gantt Chart

• Used since day one
• Updated as project progressed

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Key Design Points

• Reduced Weight
• Powerful motor
• Shell designed for least drag
• Efficient batteries and motors
• Compact size
• Integrated camera system

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Fabrication Plan

• Acquisition of parts (3 weeks) Jan 18th Feb 8th
• We will use the first few weeks of the second
  semester to acquire all our parts that are needed
  to complete the design.
• Frame assembly (1 week) Feb 8th Feb 15th
• Once the parts arrive, the construction of the
  chassis or frame must be completed.
• Motor / gearbox assembly (lt1 week) Feb 15th Feb
  22nd
• After the completion of the frame the motor and
  gearbox assembly need to be mated.
• Rotor / Swashplate assembly (lt1 week) Feb 15th
  Feb 22nd
• Once the gears and motors are mated the rotor
  shaft can be attached to the swashplate assembly.
• Shell fabrication (1 week) Feb 22nd Mar 1st
• The shell will be hand fabricated from a block of
  low density Styrofoam.
• Intergration of electronics (2 weeks) Mar 1st
  Mar 15th
• All batteries and components must be intergrated.
  This includes electronic speed controllers and
  electronic stabalizers.
• Remote Syncronization (1 week) Mar 15th Mar
  22nd
• All radio control equipment must be fuctional.
  This includes remotes and recievers.
• Preliminary flight testing (1 week) Mar 22nd
  Mar 29th
• Wireless Integration (1 week) Mar 29th Apr 5th
• Installation of wireless camera and transmitter
  with either external power supply or intergrated
  power
• Preliminary Video Testing (1 week) Apr 5th Apr
  12th
• Full systems intergration and debugging (gt 1
  Week) Apr 12th Apr 22nd

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References

• http//www.boeing.com/history/boeing/condor.html
• http//www.qinetiq.com/home/newsroom/news_releases
  _homepage/2008/3rd_quarter/qinetiq_s_zephyr_uav.ht
  ml
• http//www.robotmarketplace.com/products/carbon_fi
  ber_main.html
• http//www.robotmarketplace.com/products/motors_ge
  ared.html
• http//www.robotmarketplace.com/products/batteries
  _battlepacks_nimh.html
• http//www.spytechs.com/spy_cameras/spy-camera-c51
  00.htm
• http//www.answers.com/topic/ideo-1
• http//www.centennialofflight.gov/essay/Theories_o
  f_Flight/props/TH18.htm
• Gessow, Alfred and Garry C. Myers. Aerodynamics
  of the Helicopter. New York The Macmillan
  Company, 1952.
• Shapiro, Jacob. Principles of Helicopter
  Engineering. London Temple Press Limited, 1955.
• http//www.freepatentsonline.com/5791592.html
• http//www.thaitechnics.com/helicopter/tg5/swash_p
  late