african hawk 2 part 1

African Hawk II Automated Version

Graduation Project

Done By:

Mamdouh Sadek Al- Moatasem BelaaH

Samy Samir Khattab

Introduction

Introduction

• Mini UAVs

• Pheonix 607 (2006/2007)

• Mantis (2007/2009)

• Buraq (2008/2009)

• African Hawk (2009/2010)

Introduction

• It’s a Vision

• UAS

• Autopilot

Introduction

Objectives

• Modeling and Manufacturing of the aircraft.

• Design and installation of autopilot chip onboard of the aircraft.

Introduction

What’s New?!

• Internal Arrangement

• Landing Gear

• Vacuum Bagging

• MicroPilot Autopilot

• Emergency Recovery System

Propulsion Model

Objective

• Set Mathematical to relate parameters

• Thrust

• RPM

• Velocity

Experimental Test

• Relation between throttle position, Thrust and RPM

Measuring Thrust

Measuring RPM

Results

1- Thrust Vs. Throttle Position

y = 0.209x2 + 18.981x

R² = 0.9939

0

500

1000

1500

2000

2500

3000

3500

4000

4500

0 20 40 60 80 100 120

thru

st(g

m)

throttle position (%)

2- RPM Vs. Throttle Position

y = -0.3269x2 + 121.4x

R² = 0.9887

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

10000

0 20 40 60 80 100 120

RP

M

Throttle Position (%)

3-Thrust Vs. RPM

y = 2.5148x R² = 0.8367

0

2000

4000

6000

8000

10000

12000

0 500 1000 1500 2000 2500 3000 3500 4000 4500

rpm

THRUST(gm)

4-Endurance Vs. Throttle Position

y = 103681x-2.112 R² = 0.9964

0

20

40

60

80

100

120

140

0 20 40 60 80 100 120

End

ura

nce

- m

in

Throttle position (%)

5Thrust Vs. airplane Velocity

• BEM Theory

• CL and CD

• No geometry for blades

• 3D Scanning

• 2D Sections

Geometric Model

What’s New ?!

• Nothing Changed in the external geometry

• Some internal parts were edited

• Some new internal parts were added

Wing

Wing Ribs

Servo Motors Flap Servo

Servos Slim Servo

Fuselage

Fuselage

Fuselage Frame

Fuselage Battery Lower Holder

Fuselage Battery Upper Holder

Landing Gear Housing

Landing Gear Housing

Landing Gear Housing

Mass Model

Mass Model

• Objective:

Center of Gravity of the aircraft is related to the stability condition of the aircraft.

Moment of inertias will be needed for the calculation of the stability derivatives.

Mass Model

• Two methods of calculations:

The first method (using CAD software)

The second technique (Manual calculations)

Mass Model

• Firstly we will define the Axis system we used:

We took the center of the general Axis at the leading edge of the airfoil cross section of the wing’s root.

The +ve Z direction is upward,

the +ve Y direction is in the right wing direction from the front view,

the +ve X direction is in the direction of the fuselage rear.

Mass Model

• The aircraft is divided into 3 main sections of components:

Structural Components.

Propulsion Components.

Control Components.

Mass Model

Results

Aerodynamic model

•Cl-alfa curve

-2 0 2 4 6 8 10 12 14 16-0.2

0

0.2

0.4

0.6

0.8

1

1.2

1.4cl-alfa

alfa

cl

wing only

airplane

Aerodynamic Model

Drag polar

0 0.01 0.02 0.03 0.04 0.05 0.06 0.07-0.2

0

0.2

0.4

0.6

0.8

1

1.2

1.4 cl-cd , drag polar

cd

cl

wing only

airplane

Cm-alfa

-2 0 2 4 6 8 10 12 14 16-0.14

-0.12

-0.1

-0.08

-0.06

-0.04

-0.02

0

0.02

0.04

0.06cm-alfa

alfa

cm

wing only

airplane

Manufacturing

Master Mold

Manufacturing Steps

• Laser cutting and structure assembly

• Balsa Surface fabrication

• Composite Surface fabrication

• Surface finish

Ribs Fabricating & arrangement

• Plywood, 27 ribs.

Balsa Surface fabrication

•1.5 mm Balsa wood sheet covering

Balsa Surface fabrication

Composite Surface fabrication

• First layer: fiber glass 200 gm/m2

• Other layers fiber glass 400 gm/m3

• Lower Surface

• Painting

Master Mold

Female Mold

• Foam Jigs

• Wood Lips

Female Mold

• Gaps are sealed with clay

• Surface is waxed at least two times

Female Mold

• Applying Epoxy Resin

• Start from root

• Brush in one direction

Female Mold

• Six layers

• Around 30 min between each layer

• Most reusable part

Manufacturing

Vacuum Bagging

Manufacturing Skin Using Vacuum Bagging Technique

• What is vacuum Bagging ?!

a new technique used in composite manufacturing that used the

pressure as a clamping force to press the fiber laminates together with the mold until the resin is cured.

Vacuum Bagging

Vacuum Bagging

• Light weight Product

vacuum bagging results in absorbing of excessive resin in the breather

material and can reduce Epoxy resin weight by 30% and total weight by 15%

•Better uniformity of lay up (No thick / thin cross sections)

• exact shaping

vacuum Bagging lay up results in perfect shape that exactly like the

female mold shape due to clamping force between mold and laminate.

•Strong bonding between layers

Vacuum Bagging Layers

• Carbon fiber

• Release Fabric

• Perforated film

• Breather /bleeder

• Bag

Vacuum Bagging Equipment

1-Vacuum Pump

2-Gauge

3-hose & Regulator

Vacuum Bagging

Easy lock

Vacuum Bagging

Tubing Clamps

Vacuum Bagging

Vacuum Port

Final Shape

Manufacturing procedures •1-Cutting carbon fiber cloth

•2-Cutting vacuum bagging layers

• 3. Preparation of bag and vacuum bagging equipment

• 4. Female mold preparation

• 5-Mixing Epoxy resin

• 6. Applying epoxy on the laminate

• 7. Applying vacuum bagging layers

•8. Mold Entrance in the bag & sealing the open side

•9. Opening vacuum pump

• 10. Removing skin from the mold

• fuselage

Internal structure

Control surfaces cutting control surfaces

Control Surfaces

Balsa Leading Edges

Control Surfaces

Covering

TO BE CONTINUED………….