Agricultural Unmanned Aircraft System (AUAS)

Transcription

1 Agricultural Unmanned Aircraft System (AUAS) Team Two-CAN Albert Lee (TL) Jacob Niehus Adam Kuester Chris Cirone Michael Scott Kevin Huckshold 1

2 Presentation Overview Configuration Selection (KH) Initial Sizing (KH) Constraint Analysis (CC) Performance (CC) Aerodynamics (AL) Propulsion (MS) Stability and Control (JN) Structures (AK) Configuration (KH) Cost (MS) Conclusion (AL) 2

3 Configuration Selection Conventional Canard Biplane Tandem Wing Blended Wing Body Flying Wing Joined Wing Huckshold 3

4 Configuration Selection Conventional Canard + Tractor Canard + Pusher Final Three Configurations Huckshold 4

5 Initial Sizing Initial weight sizing model was the same for all three configurations Take-off Gross Weight = 800lb Empty-weight fraction = 0.54 Fuel-weight fraction = Huckshold 5

6 Constraint Analysis 0.2 (P/W) o Take-off Constraint Cruise Constraint Sustained Turn Constraint Landing Constraint Design Point (11.5, 0.1) (W/S) o (lbf/ft 2 ) Cirone 6

7 Performance Chris Cirone Cirone 7

8 Performance Overview AIAA Undergraduate Team Aircraft Design Competition, AIAA, Take Off Analysis Cruise Analysis Turn Analysis Mission Time Fuel Consumption Cirone 8

9 Take Off Analysis RFP Constraint: 750 ft assumed total ground roll allotment. Team Constraint: No high lift devices. Approach: Find necessary C L,TO and corresponding V TO. Assumptions Friction coefficient for grass airfield. Ideal Thrust. (T=P*η/V, and max P for take off) Drag form drag polar. (From Aerodynamics) Maximum Take Off Weight. (From Configurations) Take Off Parameters Conventional Tractor Canard Pusher Canard Minimum C L,TO Maximum V TO 68.8 mph 68.1 mph 68.0 mph Factor of Stall Speed Cirone 9

10 Cruise Analysis Description: Spray Operation Steady level flight at 20 ft AGL V op =1.3*V stall Turn Sustained turns Strategy: Determine most efficient spray pattern. Race-track pattern with turns on short ends Minimize number of turns Permits short half turns Cirone 10

11 Cruise Analysis Maximize turn radii to limit load factors and high speeds 33 Passes 30.3 ft Swath ft & ft Turn Radii 21.3 mi cruise distance Land on opposite side of field Maximizes both major and minor turn radii Cirone 11

12 Turn Analysis Priority: Validate the possibility of making the desired turns. Cirone 12

13 Mission Time & Fuel Consumption Cruise Mission Time Range: mi Spray legs V op = 72.2 mph Turns C L,stall Constant Weight 17.6 minutes Fuel Estimation RFP requirement: 20 minutes of reserve fuel Using a maximum specific fuel consumption Cruise: lbs Reserve fuel: lbs (V min,power = 60.4 mph) 2.2 Gallons Total Cirone 13

14 Future Work in Performance Climb Analysis Dynamic Weight Model Enhancement of Take Off and Turn Analysis Include improved thrust model Update Mission Time and Fuel Consumption Include all mission segments Include improved fuel consumption model Cirone 14

15 Aerodynamics Albert Lee Lee 15

16 Aerodynamics Overview Airfoil Selection Wing Characteristics Drag on the Plane Coefficients for Each Mission Segment Lift-Drag Polars Lee 16

17 Airfoil Selection NACA 1412 Simple geometry, little camber C l,max =1.6, α =16 C L,max t/c=12% x Anderson, J. D., Introduction to Flight, 5th ed., McGraw Hill, New York, Lee 17

18 Wing Characteristics Rectangular wing S ref =69.6ft 2 AR=6 C L,max =1.44, α =19 C L,max Oswald span efficiency e=0.87 Lee 18

19 Drag on the Plane Calculated parasite drag using the form factor method outlined in Raymer Conventional Canard w/ Tractor Canard w/ Pusher Component C D0 C D0 C D0 Wing Horizontal Tail Vertical Tail Fuselage Landing Gear Spray Boom TOTAL C D,L&P (% of total) C D Lee 19

20 Coefficients for Each Mission Segment Conventional C L C Do C D L/D Takeoff Cruise Turn Landing Canard w/ Tractor C L C Do C D L/D Takeoff Cruise Turn Landing Canard w/ Pusher C L C Do C D L/D Takeoff Cruise Turn Landing Lee 20

21 Lift-Drag Polars Conventional Canard w/ Tractor Canard w/ Pusher CD C L Lee 21

22 Future Work in Aerodynamics Develop CFD analysis method to get more accurate wing performance data Look into methods of providing more lift while minimizing drag, size and weight. Lee 22

23 Propulsion Michael Scott Scott 23

24 Propulsion Overview Motor Selection Propeller Sizing Engine Cooling System Fuel System Future Work Scott 24

25 Motor Selection 17 motors down selected to 4 Historical agricultural aircraft power loading 11 lbf/hp 72.7 hp needed Engine Zoche Aero-diesels (ZO 03A) UAV Engines Ltd (AR682) Rotax (912 UL DCDL) Jabiru Aero Engine (2200A) Power max (HP) RPM Scott 25

26 Thrust-Velocity Curve at Maximum RPM Zoche Aero UAV Engines Jabiru Aero Rotax 350 Thrust (lbf) Velocity (mph) Scott 26

27 Propeller Sizing Historical single engine aircraft disk loading 3 hp/ft 2 8 hp/ft 2 Fixed pitch, 3 bladed propeller Maximized blade length without tip reaching sonic velocity Implemented gear box to reduce propeller RPM Engine Zoche Aero-diesels (ZO 03A) UAV Engines Ltd (AR682) Jabiru Aero Engine (2200A) Rotax (912 UL DCDL) w/gb Pitch Chord T/hp (deg) (ft) (lb/hp) ή p,max Scott 27

28 Engine Cooling System Down-draft vs. Up-draft Entrance area directly related to horsepower Exit area set at 80% the entrance area and expandable to 200% Engine Zoche Aero-diesels (ZO 03A) UAV Engines Ltd (AR682) Jabiru Aero Engine (2200A) Rotax (912 UL DCDL) w/gb A (ft 2 ) Fuel System Fuselage fuel tank - 7 gal. - Reduce wing structure - Ease to manufacture and maintain At cruise 75% throttle - ZO 03A 2.7 gal/hr A 4.0 gal/hr UL 6.3 gal/hr - AR gal/hr Scott 28

29 Future Work in Propulsion Detailed motor analysis over throttle range Motor down select Motor mounting Actual propeller data Detailed air intake analysis Detailed fuel consumption Scott 29

30 Stability and Control Jacob Niehus Niehus 30

31 Stability and Control Overview Determine tail and control surface geometry for adequate controllability Determine center of gravity location for longitudinal static stability RFP requirement: ease of operation Niehus 31

32 Tail Sizing Method Tail volume coefficient method V h = S h c Values found from historical correlations Control surface sizing from historical dimensions l S h ref lvs V v = bs v ref Niehus 32

33 Tail Sizing Trade Study Planform area of horizontal stabilizer (ft^2) Distance between center of gravity and horizontal stabilizer (ft) Niehus 33

34 Tail Sizing Results Niehus 34

35 Longitudinal Stability Method Neutral point is the location at which pitching moment is constant with angle of attack X np = C Lα X acw C C mαfus Lα + η + η h h S S S h ref S h ref C C Lαh Lαh α h X α α h X α ach ach F + qs F + qs pα ref pα ref α p X α p Empirical values from methods in Raymer Center of gravity must fall in front of neutral point for positive static stability 2%<SM<15% Niehus 35

36 Longitudinal Stability Trade Study Neutral point location behind wing quarter-chord (ft) Distance between center of gravity and horizontal stabilizer (ft) Niehus 36

37 Longitudinal Stability Results Conventional Canard-Pusher Canard-Tractor Neutral Point X np (ft) X cgaft Center of Gravity Limits for Stability (ft) (ft) X cg forward Niehus 37

38 Future Work in Stability and Control More detailed control surface sizing analysis Lateral and directional static stability Dynamic stability in all axes Niehus 38

39 Structures Adam Kuester Kuester 39

40 Structures Overview V-n diagram and load factor Materials selection Aircraft structure Wing structure Landing gear Future work Kuester 40

41 V-n Diagram 4 3 C Design load factors Load Factor n A B D Effect of a more symmetric airfoil Nearly identical for conventional and two canards E Velocity (mph) Design Load Cruise Gust Load Dive Gust Load Maneuver Load Kuester 41

42 Materials Selection Consider durability and cost Wood Performance in weather Composites Steel Costs Heavy but strong Aluminum Lighter and commonly used Primarily aluminum Steel and composite use Properties of Various Aircraft Materials Wood Carbon Fiber Composites Stainless Steel Alloys (15-5PH) Aluminum Alloys (7075) Specific Yield E/ ρ Strength ksi 4 x10 ksi 3 lbm/in 3 lbm/in Kuester 42

43 Aircraft Structure Longerons carry bending and axial loads Bulkheads located at concentrated loads Landing gear, hopper, wing spar carrythrough Stressed skin carries shear and torsional loads Kuester 43

44 Wing Structure Wing box carrythrough Most unobtrusive option Easiest construction Wing structure Two spars Folding Wing Quarter chord and aileron support Common in general aviation Hinge towards rear of wing One or two person job Cessna Mustang with Folded Wings Kuester 44

45 Landing Gear Conventional and Canard Tractor Distance Ahead of CG (ft) Distance Below CG (ft) Conv Canard Tractor Canard Pusher Taildragger Solid spring main gear Castoring tail wheel Canard Pusher Tricycle Solid spring main gear Oleo strut front gear Prop strike Wheel sizing tires Common on light aircraft Kuester 45

46 Future Work in Structures Fuselage structure Determine shape, size, and material of members Minimize structural weight Wing structure Determine internal structure of ribs, spars, and ailerons Finalize folding wing design Landing gear Finalize placement, general dimensions, and tire size Insure durability of aircraft Kuester 46

47 Configuration Kevin Huckshold Huckshold 47

48 Configuration Objectives Estimate aircraft weight Determine internal/external layout Track CG location throughout mission Develop CAD model Huckshold 48

49 Weight Buildups Aircraft weight a sum of component group weights, defined by Raymer Equn Component weights a function of geometry, other known constants, based on historical data ie, wing weight = f (S w, AR, sweep angle, dynamic pressure, thickness ratio, load factor, TOGW) Components modeled (in addition to payload, fuel): Wings Fuselage Tail/Canard Surfaces Landing gear Installed engine Fuel system Flight controls, hydraulics Electrical system TOGW (lbs) for heaviest payload: Conventional: 771.3, Canard/Pusher: 811.0, Canard/Tractor: Huckshold 49

50 Configuration Wing and empennage sizes, positions relative to CG given by Aero, S&C Landing gear location given by Structures Most other component locations constrained- ie, flight controls must go on wings, etc. Motor must go in front (tractor) or in back (pusher) Challenge- place few remaining components to move CG to desired location, this defines fuselage length Huckshold 50

51 Center of Gravity Per S&C, 2-15% Static Margin acceptable CG locations calculated for varying amounts of fuel No payload (blue) Wet payload -235 lbs (red) Dry payload -300 lbs (green) Fuel Level (%) Conventional Fuel Level (%) Canard/Pusher Fuel Level (%) Canard/Tractor Static Margin (%) Static Margin (%) Static Margin (%) 2 0 Huckshold 51

52 Internal Layout Motor (2.38 x 1.82 x 1.5 ft.) Battery (~1 x 1 x 1 ft.) Pump (2 ft. OD sphere) Hopper (1.87 ft. x 2 ft. OD) Fuel Tank (7 gallons x 1.37 x 0.5 ft.) Fuselage diameter: 2.5 ft. Tail (tractor)/nose (pusher) cone length: 6 ft. Huckshold 52

53 Huckshold 53

54 Huckshold 54

55 Huckshold 55

56 Future Work in Configuration Develop more accurate component-based weight buildup Continue refining layout, reduce fuselage length if possible Calculate vertical CG location, envelope as payload empties Calculate moments of inertia Huckshold 56

57 Cost Analysis Conventional configuration is cheapest Costs of canards are approximately equal Conventional/Tractor Canard/Tractor Canard/Pusher Conventional/Tractor Canard/Tractor Canard/Pusher Zoche Aero-diesels (ZO 03A) UAV Engines Ltd (AR682) Fabric Aluminum Composite Fabric Aluminum Composite Jabiru Aero Engine (2200A) Rotax (912 UL DCDL) Fabric Aluminum Composite Fabric Aluminum Composite Scott 57

58 Conclusion Leading configuration: Conventional with Zoche diesel engine Cheapest and lightest configuration Best performance due to lower drag and more efficient propulsion system Smallest configuration Future Work Develop more detailed analysis methods Optimize airplane performance Lee 58

59 References [1] AIAA Undergraduate Team Aircraft Design Competition, AIAA, [2] Raymer, D. P., Aircraft Design: A Conceptual Approach, 4th ed. AIAA, Reston, VA, [3] Sobester, A., Keane, A., Scanlan, J., and Bresslof, N., Conceptual Design of UAV Airframes Using a Generic Geometry Service, AIAA , September [4] Anderson, J. D., Introduction to Flight, 5th ed., McGraw Hill, New York, [5] Bernard Hooper Engineering Ltd [online], [retrieved 7 November 2007]. [6] The Engine Specifications, Hpower-Ltd [online], [retrieved 7 November 2007]. [7] Limbach L1700 EA, L2000 EA, L2400 EB, Limbach Flugmotoren [online], 7 November 2007]. 59

60 References [8] Zoche Aero-diesels Specifications, Zoche [online], [retrieved 7 November 2007]. [9] Mikron IIIB, Moravia Inc [online], [retrieved 7 November 2007]. [10] UAV Engines [online], [retrieved 7 November 2007]. [11] Rotax Aircraft Engines [online], [retrieved 7 November 2007]. [12] Jabiru Cylinder 85bhp, Jabiru Aircraft Engines [online], [retrieved 7 November 2007]. [13] HAE-100 Data Sheet 2, Howell Aero Engines Limited [online], [retrieved 7 November 2007]. [14] 235 Cubic Inch Engine Series, Lycoming Engines-A Textron Company [online], [retrieved 7 November 2007]. 60

61 References [15] DAIR-100 Technical Features, FTI Diesel Tech, LLC [online], [retrieved 7 November 2007]. [16] Kroo, Ilan. "Tail Design and Sizing." Aircraft Aerodynamics and Design Group. Stanford University. 12 Nov [17] Chiles, I., Structures: V-n Diagrams, AE 440-A Course Notes, URL: [retrieved 13 November 2007]. [18] Federal Aviation Administration, FAR Part 23, Federal Aviation Regulations [online], URL: OpenFrameSet [retrieved 14 November 2007]. [19] Megson, T. H. G., Principles of Stressed Skin Construction, Aircraft Structures for Engineering Students, 3rd ed., Butterworth-Heinemann, Oxford, England, 1999, pp [20] Broeren, A. P., Conceptual Design Report-Preliminary Cost Model, AE440 Aerospace Systems Design I, [handout], 11 October

62 Any Questions? 62