iClean - Loitering attack UAV CDR June 27 th, 2012 Aerospace Faculty, Technion, Haifa Moshe Etlis Daniel Levy Mor Ram-On Matan Zazon Ya’ara Karniel Meiran Hagbi Oshri Rozenheck Yanina Dashevski Nathaniel Lellouche Menahem Weinberger Supervised by Dror Artzi

 PDR Overview  Remarks from PDR  Airfoil and Propeller Selection  Geometry Improvements  Performance Calculations  Wing Detailed Design  Wings’ Folding Mechanism  System Installation Layout  Weight and Balance  Wind Tunnel Model Design  Wind Tunnel Test  Conclusions and Recommendations Table of Contents

Operational capabilities:  Suicide UAV.  Endurance: 5 hr.  Range: 400 NM (approx. 750 Km)  Man in the loop.  Launching System: Mobile Ground Launcher with as many as possible UAV's ready to be launched. Target definition and acquisition:  Target type: Static and mobile.  Truck Target: detection range of 30 Km, recognition of 12 Km.  Target acquisition: Day and Night Capabilities. Attack capabilities:  Warhead: Approx. 20 Kg.  Attack capabilities: Any angle - vertical or horizontal.  Low Cost UAV unit. PDR Overview - Customer Specifications

Diving at 150 kt BOOM!! Launch Climb to 5000 ft Cruise at 5000 ft at approx. 80 kt Loiter at 5000 ft at approx. 60 kt Mission Profile

PDR Overview - Chosen Components Sensor: Controp ESP 600C (27 lbs, X15 zoom lens, degrees FOV). Engine: 3W 275 XiB2 (26 HP, 15.5 lbs). Launching Method: Booster rocket (Launched from a canister).

PDR Overview - 2 Configurations AB

PDR Overview - Final Geometry for PDR

Remarks and Solutions

Airfoil Selection NACA 0012Eppler 560 NACA 0012Eppler 560Improvement (%) Max C L Max L/D Stall angle

NACA 0012Eppler 560NACA 4412Improvement (%) Max C L Max L/D Stall angle Airfoil Selection NACA 4412

Consulting the engine data and information. The chosen engine 3W:275 XiB2 TS (from the PDR). Engine rotation speed : RPM power : 26 horsepower =~ watts. Weight: 15.5 lbs=~ 7 Kg. two blade propeller : 26x16 or 26x14 (“) 3 blade propeller : of 22x14 or 24x14 (“). Propeller Selection

(From our engine data): engine max RPM is 7000 RPM = round per second. Max speed at Propeller Selection - Calculations – Needed Pitch

Our propeller is a 2 bladed-back- folding propeller at the size of 25X18. Propeller Selection - Calculations – Needed Diameter Direction of flight

Stability Solution: Changing the Configuration

40%-60% Configuration’s Stability

Geometry as shown at PDR: Geometry Improvements The final geometry for CDR:

Old: The fuselage becomes thinner in the middle of it and then expends New: The guideline of the fuselage as much as monotonic as possible New: Wings’ hinges are covered New: canard Old: canard Old: Wings’ hinges were exposed Geometry Improvements

ValueProperty Airfoil (EPPLER 560) Aspect ratio Spans Reference lift area Weight Aerodynamic center’s position UAV’s Properties Fuselage Vertical tail

Assumptions:     The body as a lift generator componemt:   Lift Coefficient’s Properties

ValueProperty Lift coefficient slope Lift coefficient as a function of angle of attack Minimal lift coefficient at height of 0ft and 5000ft Maximal lift coefficient Stall angle Zero lift angle Lift Coefficient’s Properties

Assumptions:   Drag Coefficient’s Properties

ValueProperty Wing’s induced drag coefficient Canard's induced drag coefficient UAV’s drag Fuselage's induced drag coefficient UAV’s total induced drag coefficient Drag Coefficient’s Properties

ValueProperty Velocity ValueProperty Maximum thrust Minimum thrust Thrust for cruise flight Minimum velocity (stall) - height of 0ft and 5000ft. Assumption: Cruise flight: Assumptions:  Cruise flight  Maximal velocity: Engine Thrust

Assumption & data: Constant: Range & Endurance ResultProperty Range for climb Endurance for climb Minimum range for cruise Maximum endurance for cruise Final results:

r L F R Booster Rocket Angle

Time of opening the wings: Velocity: Density: The mass : :The lift coefficient The acceleration of the booster: Area of wing that creates the lift: The force that booster applies: The lift: The total moment: 27 Assumptions and data: Booster Rocket Angle

Wing Detailed Design

The lift load distribution on a trapeze wing: Wing Detailed Design - Load Distribution

Assuming this lift load distribution the resultant force is:

Wing Detailed Design - Web Thickness

Wing Detailed Design - Flange Area bl [mm] Flanges bl [mm]

Wing Detailed Design - Skin Thickness Thickness [mm] Material 706.3Carbon Fibers 290.4Aluminum 2024-T Aluminum 7075-T6

The selected method is the vertical pin for the Advantages below:  Structural simplicity  Load paths determined with Confidence  Minimum volume of hinge  Simple actuator mechanism  Very few moving parts  Minimum weight Wing Detailed Design - Joint Selection

A vertical pin through the pivot axis transfer the force-couple from the movable outer wing to the fixed center section Wing Detailed Design - Joint Selection Carbon fiber ± 45 ° Unidirectional Wing's root

Wing Detailed Design - Final Formation

Wing Detailed Design - Strength Analysis

Force and Moment Calculations: Conclusion from Allowable and Actual Stresses Calculations: Wing Detailed Design - Strength Analysis

Shear Stress Von Mises

Max. Deformation [mm] Material 6 Aluminum 2.3 Carbon Factor Calculation: Wing Detailed Design - Strength Analysis

Pre Calculations: the average velocity of the UAV during launch time is: Reference areas : Wings’ Folding Mechanism

The wing‘s lift during launch time The wing‘s drag during launch time: Tension Drag Wings’ Folding Mechanism

Tension Drag Direction of flight Drag Wings’ Folding Mechanism The wing‘s drag during launch time:

Movement limiters Main spring Connecting rods Bearing Wings’ Folding Mechanism - Other Related Parts Design

Booster for launch Motor & Propeller Integral fuel tank Warhead EO Sensor Wing & Canard Opening mechanism Avionics Internal Layout

S/N Part nameMass[gr] X[cm]My[N*cm] 1StructureFuselage Wings Mechanics –wing Reinforcements- wing Canard wings Mechanics-canard Reinforcements- canard Tail Fuel injection system Engine Fuel Fuel tank Oil Warhead PayloadSensor Battery AvionicsComputer+Control system Total Mass : CGx[cm]: Weight and Balance

Cg=107.5 cm Cp=111.2 cm Weight and Balance - C.G Location 10% chord stability margin

General instructions:  Max. length: 100 cm.  Max. section area: 2-4% of cell’s section area.  Wing tips should be away from the cell’s walls.  Model shouldn’t be too small in order to get accurate results. The model’s scale will be 1:7. Wind Tunnel Model Design

Steel reinforcement Hinge Morse cone CanardWing Drawn nose Steel holder

Wind Tunnel Model Design Although in order to keep similarityrules, we had to use an air speed that is greater than 80 m/sec for the experiment, we wanted to avoid the situation in which model’s wings can’t handle the lift loads so we lowered the air speed to 45 m/sec.

Wind Tunnel Model Design Experiment purpose:  Find the 2D lift coefficient slope, stall angle, pitch and yaw moments coefficients.  Learn about UAV’s stability status.  Learn about situations where a flow separation may occur. Air Speed [m/sec] AOA Range [Degrees] PlaneConfiguration Experiment Code No LongitudinalOpen LateralOpen LongitudinalClosed LateralClosed LongitudinalOpen LongitudinalOpen wing only - With tufts LongitudinalFuselage only73857

The different configurations: Open Closed Open with tuftsOpen, wings only with tufts Fuselage only Wind Tunnel Model Design

Wind Tunnel Model

Wing Tunnel Test Results Lift Coefficient for Open Configuration The graph above demonstrates the tunnel results of the total lift coefficient as function of angle of attack in comparison to the calculated theoretical lift coefficient.

Wing Tunnel Test Results Lift Coefficient for Open Configuration The graph above demonstrates the Lift coefficient as function of angle of attack of each lift-generator part of the UAV.

Wing Tunnel Test Results Moment Coefficient for Open Configuration The graph above demonstrates the tunnel results of the total lift coefficient as function of lift coefficient in comparison to the calculated theoretical lift coefficient.

Wing Tunnel Test Results Moment Coefficient for Open Configuration The graph above demonstrates the Moment coefficient as function of angle of attack of each lift-generator part of the UAV.

Wing Tunnel Test Results Drag Coefficient for Open Configuration The graph above demonstrates the tunnel results of the drag coefficient as function of angle of attack in comparison to the calculated theoretical drag coefficient.

Wing Tunnel Test Results Lift Coefficient for Closed Configuration The graph above demonstrates the tunnel results of the total lift coefficient as function of angle of attack in comparison to the calculated theoretical lift coefficient.

Wing Tunnel Test Results Moment Coefficient for Closed Configuration The graph above demonstrates the tunnel results of the total lift coefficient as function of angle of attack in comparison to the calculated theoretical lift coefficient.

1. Improving geometry. 2. Performances estimation. 3. Wing design. 4. Wing & canard opening system. 5. Structural analysis. 6. Building a wind tunnel model or airplane model. And more Work Plan for Current Semester – as Seen on PDR

1.Strengthening the wind tunnel model. 2. Perform additional wind tunnel test on the wings and canards in order to evaluate their mutual affect on each other. Conclusions and Recommendations

Questions?