SYSTEM DESIGN REVIEWP10232 – UAV AIRFRAME C

Daniel Graves – Project LeadJames Reepmeyer – Lead EngineerBrian Smaszcz – Airframe DesignAlex Funiciello – Airfoil DesignMichael Hardbarger – Control Systems

Project DefinitionMission Statement:

The goal of the UAV Airframe C project is to provide an

unmanned aerial platform used for an aerial imaging

system. The airframe must support the weight and

interfaces for the designed imaging system. The aircraft

must be operated remotely and be a viable alternative to

current aerial imaging methods. This is a second

generation airframe, expanding on the previously laid

ground work established by the P09232 UAV B Senior

Design Project.

Customer NeedsKey Project Goals: Airframe must be able to carry a fifteen pound payload Easy integration with measurement controls box and

different aerial imaging systems Ability to remotely control aircraft and activate payload Ability for flight communication between aircraft and

ground relay Aircraft provides twenty minutes of flight time for local

area photography Aircraft has the potential to take off and land on site Easy assembly and disassembly of the aircraft for

transportation

Lessons Learned From P09232 The aircraft’s wings sheared off shortly before

impact. The failure was determined to be from the bending stress applied to the wings during the banked turned.

After analysis, it was concluded that the main

fiberglass spar used to support the wing was not selected properly to handle the flight loading.

High bend in the wing during flight inhibited the pilot’s control of the aircraft by reducing the effectiveness of the control surfaces.

Risk AssessmentID Risk Item Effect

Importance Action to Minimize Risk

1 Flight Test Failure

Team fails to meet project deliverable 9

Design aircraft and associated tests correctly. Study weather for optimal test conditions

2

Meeting Project

Deadlines

Project will run behind schedule, or project deliverables are not met 6

Create proper schedules with an appropriate buffer time between dependent actions

3 Component Redesign

Forced project redesign can force the project to run over deadlines 3

Smart aircraft design with proper backing analysis. Compliance with subsystem interface designs.

4 H1N1/Illness Team members can fall behind in work 3 Proper cleanliness and Hygiene

Risk AssessmentID Risk Item Effect

Importance Action to Minimize Risk

5 Build Time Runs Over

Delay in meeting project deliverable, flight testing does not run on schedule 4

Begin build phase early and maintain positive team morale

6 Component

Testing Failure Delay in project deliverable or testing schedule 2

Test parts early and properly design all critical systems

7

Miscellaneous Damages/Theft

Loss of progress and time 3 Ensure all parts are properly stored and secured

8

Budget Increase

Needed

Unable to purchase critical parts needed for aircraft design and build 2

Have budget clearly defined and avoid expensive components where possible

9 Budget Driven

Redesign

Team will have to redesign aircraft systems, increasing time needed for completion 3

Have budget clearly defined and avoid expensive components where possible

Risk AssessmentID Risk Item Effect

Importance Action to Minimize Risk

10 Part Lead Time

Parts required for assembly delay build progress 2

Order parts at the end of MSDI and make sure all parts are ordered

11 Team Member

Injury

Team member can fall behind in work resulting in a progress delay 2

Every team member acts in a responsible manner ensure work is done in a timely manner

12Critical Data

Loss

Component re-design or analysis will need to be repeated 2

All documents are backed up on EDGE

13 Winter Break

Start Up

Ramp up time for project build is longer due to winter break 2

Continue work and project updates during the winter quarter

Control Interfaces (physical)

Control Interfaces (electrical)

Body Structure The structure shall support 15lbs of payload. The structure shall have an accessible payload

bay. The structure shall assemble/ disassemble for

transport. The structure shall resist deformation under

normal operation. The structure shall house the planes power

system and provide a mount for the engine. The structure shall be durable, enabling

multiple flights without servicing.

Airframe Concept Goals Reduce weight of airframe compared to UAV B

Improve aerodynamics

Improve in-flight stability and handling properties

Optimize payload integration and removal

Design airframe to highest “open architecture” capability

http://mae.ucdavis.edu/~EAE127/index_files/1008033.jpg

Airframe Concept Selection Standard monoplane design.

Top mounting wing capability.

Detachable conventional tail section.

Configuration used in small aircraft and

RC trainer planes.

Simple design allows for shorter build

time.

http://www.hooked-on-rc-airplanes.com/images/rc-trainer-planes6.jpg

http://www.excelaviation.ca/index_files/image004.jpg

Airframe Fuselage Concepts Twin-boom

Tandem wing

Canard Style

Flying wing

Delta wing

http://www.spyflight.co.uk/images/

www.viswiki.com/en/Tandem_wing

http://commons.wikimedia.org/wiki/File:Vulcan.delta.arp.jpg

http://advancedaerospacellc.com/jcfly%2015%25.jpg

http://upload.wikimedia.org/wikipedia/commons/4/4a/YB49-2_300.jpg

Airframe Selection Matrix

Monoplane Bi-plane Delta Flying Wing

Tandem Wing

Split Body

Boom Tail

Design 0 - - - - - - - - - Cost (initial) 0 - 0 + - - - - +

Piloting Difficulty 0 - - - - - + 0

Transport 0 + - - - - + Flight Time 0 0 0 ++ + + 0

Payload Flexibility 0 0 - - - ++ - -

Payload Weight 0 0 0 + ++ + 0

Airspeed 0 - + - 0 - 0 Total 0 -3 -3 -4 -2 -3 -1

Airframe Tail Concepts

http://www.flightdesignusa.com/

http://media.photobucket.com/

http://www.aviationspectator.com/

http://farm2.static.flickr.com

Conventional

T-Tail

Cruciform

Twin-Tail

V-Tail

http://en.wikipedia.org/wiki/File:Jetstream31.jpg

Airframe Tail Selection Matrix

Cambered H-Tail V-Tail T-Tail Cruciform

Stability 0 + + - -

Design Difficulty 0 - -- -- --

Weight 0 - + - -

Controllability 0 + - + +

Drag 0 + + 0 0

Flight Envelope 0 0 0 + +

Cost 0 - - - -

Total 0 0 -1 -3 -3

Tail Airfoil Selection Lifting tail will be used to counter wing

moment A low cambered foil will be used to

minimize drag

Airfoil Specifications The airfoil shall provide enough lift to carry the craft. The airfoil shall minimize drag. The wing shall be able to be disassembled. The wing shall be structurally rigid and free of in flight

flutter. The wing shall contain control surfaces. The wing planform area shall be designed such that

wing loading is kept under 20 oz./ft2. The wing shall be structurally sound. The wing shall resist deformation under loading.

Airfoil Selection MatrixHigh Camber- Flat Bottom

High Camber - Under

Cambered Low Camber Reflex Symmetric

Lift 0 + -- -- --

Drag 0 + + - -

Stall Angle 0 + - - 0

Stall Speed 0 + - - 0

Moment 0 - + ++ +

Structure 0 - 0 0 0

Total 0 2 -2 -3 -2

Airfoil Concept Selection Add additional camber compared to last

yearflat bottom under camber design

Increase lift Decreases stall speed Decrease required chord and wingspan

Flat bottom v. Under Camber

NACA-9412

S7055

Airfoil coordinates from UIUC airfoil database

Airfoil Lift comparison

Comparison from the Airfoil Investigation Database, with data taken from the UIUC airfoil database

Airfoil Drag Comparison

Comparison from the Airfoil Investigation Database, with data taken from the UIUC airfoil database

General Comparison

S7055 (10.5%) Flat-Bottomed NACA-9412

Thickness (%) 10.5 11.979Camber (%) 3.548 8.998Trailing Edge Angle (%) 10.876 13.718Lower Surface Flatness 91.63 38.129Leading Edge Radius (%) 1.379 1.671Maximum Lift (CL) 1.203 2.096Maximum Lift Angle-of-Attack (deg) 9 12.5Maximum Lift-to-drag (L/D) 52.646 58.659Lift at Maximum Lift-to-drag 0.942 1.412Angle-of-Attack for Maximum Lift-to-drag (L/D) 5.5 3.5Stall Angle 9.0 12.5

Data from the Airfoil Investigation Database

Airfoil selection Final selection of the airfoil will be based

on XFOIL analysis Using refined weight estimates, a

specific lift requirement may be chosen Planform area will be selected based on

desired wing loading to maintain trainer like flight behaviors

Power restrictions of the selected motor will mandate the specific drag requirements

Launch and Recovery Concept Selection Catapult (or crossbow) style launch

platform Car-top launch setup Removable (leave-behind) Landing Gear Retractable landing gear

http://mm04.nasaimages.org/MediaManager/srvr?mediafile=/Size4/nasaNAS-9-NA/59991/0100743.jpg&userid=1&username=admin&resolution=4&servertype=JVA&cid=9&iid=nasaNAS&vcid=NA&usergroup=Marshall_-_nasa-9-Admin&profileid=41

http://www.uavs.biz/images/catapult_launch.jpg

Landing gear The landing gear shall allow the plane to

taxi and takeoff. The landing gear shall protect the plane

during takeoff, landing, and taxiing. The landing gear shall provide minimal

resistance on a grass runway.

Landing Gear Skids or Skis Floats (Pontoons) 2 or fewer wheels

(combination of wheels and skids)

3 wheels (traditional setup)

More than 3 wheels

http://www.oursbiz.com/Products/b/195/Pitts-S-2A-SP-002--987230.jpg

http://anjo.com/rc/aircraft/dr1/dr1.gear.1.jpg

Landing Gear Layout

http://www.jacksonrcclub.org/images/landing_gear_types.jpg

Landing Gear Selection Matrix

Conventional Tricycle

Skid Plates

Pontoon/Floats Skis

Drag 0 + + - - 0Ground Control 0 0 - - - 0Nose Over 0 ++ - 0 0Ground Loop 0 + - 0 0Cost 0 - + + -Load Handling 0 - + + 0Risk of Prop Damage 0 - - - 0Cargo Protection 0 - - - 0 0Operational Environment Restrictions 0 0 - - - - -Total 0 0 -5 -4 -3

Flight controls The flight control system shall allow the

aircraft to be flown like a basic trainer aircraft.

The control system shall maintain reliable control for at least 20 min.

The control system shall interface with the payload.

Flight Control Actuation Selection

Electric (servo)

Electric (stepper) Pneumatic Hydraulic EHA

Difficulty of Design 0 - - - --

Complexity 0 -- - - --Quick Connect compatible 0 0 -- -- 0

Weight 0 - - -- 0

Power output 0 0 + ++ ++

Maintenance 0 0 - - -

Cost (initial) 0 - 0 - --

Cost (sustained) 0 - 0 - -

Total 0 -6 -5 -7 -6

Propulsion The propulsion system shall provide

power for at least 20 min. The propulsion system shall provide

enough thrust to accelerate to flight speed.

The propulsion system shall be clean and easy to maintain.

The propulsion system shall be reusable.

Propulsion Concept SelectionRC Airplanes Rely on 1 of 3 Types of Propulsion

○ Gas

○ Glow/Nitro

○ Electric

Gas Propulsion Small Gasoline

Powered Engine Typically Two-Cycle Traditional RC

Aircraft Propulsion Method

Longer Flight Time with Gas RC Planes

Glow/Nitro (?) Fuel: Nitrous Oxide (?) Will not be considered for

this project due to fact that it is not manufactured in sizes not large enough for the scope of this project.

Electric Uses Batteries to

Power MotorBrushed DCBrushless DC

Due to Need for Batteries it has a Short Flight Time

Battery Capacity To find the required battery capacity to

operate each motor for 20 minutes the following equation was used:

Gas Critical Analysis

Electric Critical Analysis

All Motors Analyzed Were DC Brushless Two Different Typical Li-Po Battery Packs

Were Used

Propulsion Selection Matrix

Glow/Nitro Gasoline Electric Initial Cost * 0 0 Running Cost 0 0 + Controllability 0 0 + Power * 0 - - Weight 0 0 - -

Design Flexibility 0 0 ++

Fuel/Battery Consumption 0 0 0

20 min Flight Time * 0 0

Vibration 0 0 + Reliability - 0 ++ Maintenance 0 0 ++ Total N/A 0 5

*Glow engines of the size required would need to be a custom made part, as such they are not available for our use

P10232 System Design Concept Monoplane

Electric propulsion?

Standard cambered tail section

Under-cambered airfoil

Rectangular wing section

Top-mounted wing to the airframe

Conventional landing gear

Questions?P10232 TeamDaniel GravesJames ReepmeyerBrian SmaszczAlex FunicielloMichael Hardbarger

https://edge.rit.edu/content/P10232/public/Home