HELIPLAT : Detail Design & Manufacturing of a Scaled Prototype for High Altitude Very-Long Endurance Solar-Powered RPAS

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1 : Detail Design & Manufacturing of a Scaled Prototype for High Altitude Very-Long Endurance Solar-Powered RPAS Prof. Ing. Giulio ROMEO, E. Cestino, F. Danzi, M. Cassaro, G. Frulla, F. Borello, G. Correa, G. Corsino, M. Pacino, Politecnico di Torino Dept. of Mechanical and Aerospace Eng. giulio.romeo@polito.it DIMEAS All information on Heliplat and VESPAS project contained in this document is property of Prof. G. Romeo, Dept. of Mechanical & Aerospace Eng. - Politecnico Torino. All rights reserved.

2 A.S.I. ( ) EC: 5FP ( )- 6FP ( ) NETwork of HELIplat RPAS High Altitude (15-20km) Very-long Endurance Solar Powered Autonomous Stratospheric RPAS (VESPAS) flying for long period of time (4-6 months) by solar-power & fuel cells system. Easily recovered for maintenance. Pseudo satellites, with advantage of being much cheaper, closeness to the ground (more detailed land vision), more flexible, with continuous spatial resolution than a real satellite. 8-9 HeliPlat would continuously monitor Med Sea from Turkey to Spain. An area with 300km diameter can be monitored. Many other applications can be foreseen by such platforms. 2

3 Homeland Security Airborne or Ground Sensors Predator B IAI Borders Patrol, actually, is made by piloted airplanes or helicopters (several personal) or from military ships, increasing the cost tremendously. Costs sustained by Italian Coast Guard for their ATR-42 airplane equipped for border surveillance (7 crew minimum), is around /hour of fly. By UAV flying at km altitude and with proper sensors, is possible to detect boat or people and with Total Life Cycle Cost of around /hour fly Satellite Earth Observation Typically, satellite sensors may bring a good accuracy - but such high accuracy data remain quite expansive today. Several satellites system used for earth observation are useless for a continuously real-time border surveillance due to their limited spatial resolution. 3

4 Facebook & Google: Solara Titan Aerospace Homeland Security DARPA Boeing $100 million contract AIRBUS D&S Qinetiq Zephir 7 70,740ft TOGW 100kg, Pl: 5kg Solar Impulse 2 4

5 A A A CRITICAL ASPECT: ENDURANCE & STATION KEEPING Main requirement: Avoid interference with civil transport traffic Main advantage of the VESPAS-RPA: less climb and descend events; A important for interference with the aviation traffic. Any other high-altitude RPA configuration for border surveillance has a very limited endurance (24-36 hours) that would drastically increase A any potential collision risk with civil aviation traffic. At least a double number of RPAs would be requested to continuously A guarantee the surveillance service, highly increasing the System Total Life Cycle Cost. A At least 4 MALE RPAs are requested to cover continuously the same area covered by HALE, since the covered area is decreasing with the square value of the flying altitude. Total Life Cycle Cost of MALE A system shall tremendously increase. Main Advantage with respect to Aerostatic RPA: high station keeping also with strong jet stream Copyright by G. Romeo

6 Very Long Endurance Solar-Powered Autonomous Aircraft 6

7 SOLAR CELLS Maximum available Solar cell efficiency: 85%. To-date obtained eff.: 36%. High efficiency (25%) thin (150 microns) mono-crystalline silicon cells are to-day available at low-medium price (about 2000 /m2). Higher efficiencies (up to 30-35%) very thin (50 microns) single-crystal silicon or GaAs cells are also available, at higher price (about k /m2). DIMEAS GaAs CELL: 30% Cost: 30 k /m2 efficiency > 25% Si mono-crystalline 25% Efficiency Cost: 100 k /m2 Triple-junction CELL: 32% 7

8 (HELIos PLATform) WT=850kg; Wpl=130kg; Preq=6.5kW; Ppl=1.5kW; Vc=71km/h (TAS); Solar cell effic. 21%; Fuel cell effic. 60% Sw=176.5m2; b=73m; ARw=30.2; S ht=28m2; b=17.5m; Jet-stream up to 150 km/h EC 5FP Multi-disciplinary optimisation program: 1) Solar radiation change over year; 2) Altitude; 3) Wind speed; 4) Structural mass. 5-6) Mass and efficiency of solar cells and of fuel cells; 7) Aerodynamic performances; Trademark:POLITECNICO DI TORINO, DIASP, Giulio Romeo 8

9 CL DIMEAS Aerodynamic Design New high performances airfoils developed to reduce the power required for the flight. Cl-Alpha HPF118 profile - Re= Alfa Xfoil Stuttgart VSAERO CFD 9

10 EASA CS-VLA n= 3.8 Scaled Prototype Design & Manufacturing POLITO HM CFRP material: very light - high stiffened structure. 10

11 Scaled Prototype Manufacturing and Testing DIMEAS Wing span: 24m Shear/Bending Static Failure Test N=7.5g 11

12 3 HALE UAVs WP Leader: Prof. G. Romeo MTOW ----> 7700 kg; Payload weight ---> 500 kg Propulsion ----> 559 kg; Wing Span ---> 32 m Ceiling ----> 20 km; Endurance ---> 24 hrs Fuel weight ----> 3400 Kg; Max Airspeed ---> 340 Kt POLITO IAI - POLITO SHAMPO (Solar Hale Aircraft Multi Payload & Operation) MTOW ---> 950 kg; Payload weight ---> 150 kg Ceiling ---> km; Payload Power ---> 1.5 kw Endurance ---> months; Wing Span ---> 73 m 12

13 SESA FLIGHT MODEL Latitudine DIMEAS Autopilot/Manual Hardware EASA VLA n=3.8g Planned Flight Mission Traiettoria in 4,52E+01 4,52E+01 Experimental Recorded Mission 4,52E+01 4,52E+01 4,52E+01 4,52E+01 4,52E+01 WOURLD AIR GAMES Turin ,52E+01 4,52E+01 4,52E+01 7,680 7,682 7,684 7,686 7,688 7,690 7,692 7,694 7,696 7,698 7, Longitudine 13

14 Flight Test Site: Tarquinia Lido TANGO Demo Mission Architecture DIMEAS AutoPilot Data IRIDIUM data

15 DIASP ENvironmentally Friendly Inter City Aircraft powered by Fuel Cell Electric-motor airplane powered by fuel cells validated by flight-test. Rapid 200-Fuel cell 2010 by Prof. G. Romeo. V top =160 km/h V max av 1run =142 km/h V max av 2run =135 km/h V max av 4run =133 km/h Endurance: 49 min FAI Class C Aeroplane FAI World Speed Record FAI World Endurance Rec 15

16 Preliminary Design Research Contract n.606/2014, Sept with: SHENYANG AEROSPACE UNIVERSITY, CHINA Detail Design of a Scaled Prototype for 1 month Flight Endurance High Altitude Long Endurance Solar-Powered UAV The SAU technical requirements include: 1) Payload weight: 10-15kg; 2) endurance: 1 month; 3) Flight altitude and latitude; The POLITO technical files shall include: (1)Technical drawings of 3D model including whole structure; (2)Analysis files of FEM model and results including whole structure; (3)Aerodynamic performance data; (4)Technical files for processing and manufacturing. (5)Technical files and drawings for solar power system include solar power panel system, battery system, electric motors and controllers. (6)Flight Dynamic law and Design of flight control system. 16

17 SHENYANG AEROSPACE UNIVERSITY, CHINA Liaoning General Aviation Academy (LGAA) UAV FC Faku airfield 17

18 Very Long Endurance Solar-Powered Autonomous RPA VESPA must have amount of rechargeable batteries to fulfill the energy requirement during night-time. Batteries' weight greatly affects the operational envelope of such aircraft. 18

19 Aerodynamics Power balance Structural requirements Preliminary Sizing Multidisciplinary Design Optimization Weight estimation Flight Mechanics Constraints 1 month of continuous 42 N latitude 17 km altitude 15 kg payload solar cells efficiency 25% battery energy density 260 W/kg Main Outcomes High aspect-ratio wing to achieve high efficiency and power index Very low gross weight more than 30% battery 19

20 Preliminary Design Best Configuration Design 20

21 Weight breakdown Overall weight 2056 N Structural Analysis 2 counter posed C-spars made by carbon-epoxy composite upper and lower panels made by carbon epoxy composite Equal-spaced multi ribs Gross weight breakdown Structural weight breakdown 21

22 Structural Analysis - Wing Box 22

23 Structural Analysis - Wing Box Wing deflection at n=1, n=3, n=4.5 4,28 m 2,85 m 0,95 m 23

24 Structural Analysis Horizontal Tail Vertical Tail Booms 24

25 Flight Simulator Automatic Flight Control System 25

26 INPUT DATA Flight Speed: V= 20 m/s; Blade radius: R= m; Thrust: T= 26 N; Altitude: z= m; OUTPUT DATA Propeller Efficiency, η; Propeller adimensional coefficients Power absorbed at shaft, P a [W]; Torque absorbed at shaft, C a [Nm] Optimum Propeller design process Propeller On-design study: parametric analysis for E. Cestino 26

27 CONCLUSION DIASP Possible realisation of HAVE-UAV at least for low latitude sites in Europe and for 4-6 months. Airfoils with high Lift coeff. and small Drag coeff. and at low Reynolds numbers were obtained. The aerodynamic performances of were implemented by VSAERO software, obtaining very high efficiency. Showed feasibility of very light CFRP structural elements. Good correspondence between experimental analytical and FEM analysis was verified. The experimental flight tests validated several critical technologies for high altitude very long endurance flight: high efficiency solar cells, electric brushless motor, controllers, video and thermo camera image transmission, telemetry system Flight Tests of Fuel cell Powered Aircraft showed the feasibility of long endurance UAV The 30 days endurance flight, planned for next year, should be a great step in direction of a new solar powered RPAS 27

28 Grazie per la vostra gentile attenzione G. Romeo, Polito, DIMEAS: partner di progetti EC ESA STRAT S 28