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Romano D.G.,Piaggio | Alfredsson P.H.,KTH Royal Institute of Technology | Hanifi A.,KTH Royal Institute of Technology | Hanifi A.,Swedish Defence Research Agency | And 7 more authors.
Applied Mechanics and Materials | Year: 2013

This document explains in its first part the design procedure adopted to design the contoured sidewalls of a swept-wing airfoil section mounted in a wind tunnel in order to satisfy the infinite swept-wing approximation. In the second part, the experimental set-up is described as well as the first results of the experimental campaign. The sidewalls are shown to play their role properly and satisfactorily provide the infinite swept-wing conditions required for subsequent investigations of the most important vortex receptivity mechanisms responsible for excitation of crossflow and Tollmien-Schlichting instability modes in the airfoil boundary layer. © (2013) Trans Tech Publications, Switzerland.


Dimino I.,the Italian Aerospace Research Center | Concilio A.,the Italian Aerospace Research Center | Schueller M.,Fraunhofer Institute for Electronic Nano Systems | Gratias A.,Fraunhofer Institute for Electronic Nano Systems
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2013

A key technology to enable morphing aircraft for enhanced aerodynamic performance is the design of an adaptive control system able to emulate target structural shapes. This paper presents an approach to control the shape of a morphing wing by employing internal, integrated actuators acting on the trailing edge. The adaptive-wing concept employs active ribs, driven by servo actuators, controlled in turn by a dedicated algorithm aimed at shaping the wing cross section, according to a pre-defined geometry. The morphing control platform is presented and a suitable control algorithm is implemented in a dedicated routine for real-time simulations. The work is organized as follows. A finite element model of the uncontrolled, non-actuated structure is used to obtain the plant model for actuator torque and displacement control. After having characterized and simulated pure rotary actuator behavior over the structure, selected target wing shapes corresponding to rigid trailing edge rotations are achieved through both open-loop and closed-loop control logics. © 2013 SPIE.


Dimino I.,The Italian Aerospace Research Center | Flauto D.,University of Palermo | Diodati G.,The Italian Aerospace Research Center | Concilio A.,The Italian Aerospace Research Center | Pecora R.,University of Naples Federico II
Recent Patents on Mechanical Engineering | Year: 2014

Shape control of adaptive wings has the potential to improve aircraft aerodynamic performance during cruise. In recent years, several patents have been issued for inventions in the field of morphing wings, using hydraulic, electromechanical or smart material-based actuation concepts and architectures. In the framework of SARISTU project (EU-FP7), the joint integration of different conformal morphing concepts in a laminar wing is investigated to improve aircraft performance through a 6% drag reduction, with a positive effect on fuel consumption and required take-off fuel load. An innovative seamless morphing wing incorporating a gapless morphing leading edge, a morphing trailing edge and a wingtip active trailing edge is developed to pursue optimal wing geometry for any flight condition. This paper proposes a state of the art technology to design the actuation system of a morphing trailing edge, consisting of a flexible outer skin and an internal driving mechanism. Focus is given to the modeling and analysis of the morphing actuation, and its integration in the seamless flexible trailing edge control surface. The actuation system is driven by servo rotary actuators and it is designed and established to control the wing trailing edge in order to obtain pre-defined airfoil shapes maximizing wing aerodynamic efficiency. The actuation concept relies on a quick-return mechanism driven by load-bearing actuators controlling the morphing ribs individually. The actuation system is both analytically and numerically addressed. To validate the design, experiments are then carried out with the purpose of estimating the control movement functions suitable for single airfoil camber variations. The morphing rib kinematics including the actuation system is designed to withstand operational pressure loads and actuation forces. © 2014 Bentham Science Publishers.


Dimino I.,The Italian Aerospace Research Center | Concilio A.,The Italian Aerospace Research Center | Pecora R.,University of Naples Federico II
24th AIAA/AHS Adaptive Structures Conference | Year: 2016

In morphing structures, actuation is a key system for general aircraft-level functions. Similarly to the demonstration of safety compliance applied to aircraft control surfaces, novel functions resulting from the integration of a morphing device (ATED), imposes a detailed examination of the associated risks. Because of the concept novelty, literature references for a safe design of a morphing trailing edge device are hard to be found. The safety-driven design of ATED requires a thorough examination of the potential hazards resulting from operational faults involving either the actuation chain, such as jamming, or the external interfaces, such as loss of power supplies and control lanes. In this work, a study of ATED functions is qualitatively performed at both subsystem and aircraft levels to identify potential design faults, maintenance and crew faults, as well as external environment risks. The severity of the hazard effects is determined and placed in specific classes, indicative of the maximum tolerable probability of occurrence for a specific event, resulting in safety design objectives. A fault tree is finally produced to evaluate the impact of actuation kinematics on specific aspects of ATED morphing operation and reliability. © 2016, American Institute of Aeronautics and Astronautics Inc, AIAA, All rights reserved.


Errico A.,The Italian Aerospace Research Center | Angelino C.V.,The Italian Aerospace Research Center | Cicala L.,The Italian Aerospace Research Center | Persechino G.,The Italian Aerospace Research Center | And 16 more authors.
International Journal of Remote Sensing | Year: 2015

The use of remote-sensing images is becoming common practice in the fight against environmental crimes. However, the challenge of exploiting the complementary information provided by radar and optical data, and by more conventional sources encoded in geographic information systems, is still open. In this work, we propose a new workflow for the detection of potentially hazardous cattle-breeding facilities, exploiting both synthetic aperture radar and optical multitemporal data together with geospatial analyses in the geographic information system environment. The data fusion is performed at a feature-based level. Experiments on data available for the area of Caserta, in southern Italy, show that the proposed technique provides very high detection capability, up to 95%, with a very low false alarm rate. A fast and easy-to-use system has been realized based on this approach, which is a useful tool in the hand of agencies engaged in the protection of territory. © 2015 Taylor & Francis.


Sanders L.,ONERA | Mincu D.-C.,ONERA | Denis W.,ONERA | Vitagliano P.L.,the Italian Aerospace Research Center | And 4 more authors.
20th AIAA/CEAS Aeroacoustics Conference | Year: 2014

This paper deals with the computation of CROR installation effects in terms of tone noise within three separated steps. The first step aims at computing the aeroacoustic sources of a CROR by a CFD approach, namely a URANS method applied to counter-rotative propellers. The second step computes the acoustic field radiated by the isolated CROR. It is based on the Ffowcs-Williams and Hawkings (FW-H) surface integral method and uses the blade pressure fluctuations computed by CFD as input data. The last step computes the acoustic field scattered by the aircraft geometry within the Boundary Element Method using the incident acoustic field previously computed. This approach in three steps is applied on a 1/7th scale model of a regional aircraft design equipped with two CRORs and tested in windtunnel. The paper first focuses on the aeroacoustic study of the CROR including the effects of pylon and incidence. The numerical prediction of the CROR noise in take-off conditions is then compared to the experimental measurements of the isolated engine. The isolated CROR noise computation is globally underestimated compared to the measurements because it doesn't take into account the acoustic reflections occuring in the windtunnel but a qualitative agreement is found between the computation and the measurements. Finally, the computation of CROR installation effects is presented in one of the aircraft configuration tested in windtunnel, showing a global increase of the tones when the CROR is installed in comparison with the isolated configuration.


Angelino C.V.,The Italian Aerospace Research Center | Cicala L.,The Italian Aerospace Research Center | De Mizio M.,The Italian Aerospace Research Center | Leoncini P.,The Italian Aerospace Research Center | And 4 more authors.
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2013

This paper presents a new low-complexity H.264 encoder, based on x264 implementation, for Unmanned Aerial Vehicles (UAV) applications. The encoder employs a new motion estimation scheme which make use of the global motion information provided by the onboard navigation system. The results are relevant in low frame rate video coding, which is a typical scenario in UAV behind line-of-sight (BLOS) missions. © 2013 Springer-Verlag.


Dimino I.,The Italian Aerospace Research Center | Vitiello P.,The Italian Aerospace Research Center | Aliabadi F.M.H.,Imperial College London
Recent Patents on Mechanical Engineering | Year: 2013

Sound radiation from vibrating panels plays a crucial role in the study of interior noise in transportation vehicles. In recent years, several patents have been issued for inventions in the field of sound reduction technologies to mitigate aircraft noise. This work presents a theoretical analysis and simulations to investigate sound transmission through plate-like multi wall structures. An analytical model is developed to predict sound transmission through infinite-sized triple panel partitions placed in a rigid baffle, from a viewpoint of practical noise control. A numerical procedure is also developed to evaluate the transmission characteristics of finite partitions due to an incident diffuse field. The method is based on a hybrid FEM/Rayleigh methodology and utilizes numerically calculated sound transmission loss of flat multi panel partitions and box like cavities with idealized boundary conditions. Two simplifying assumptions are made: the surrounding medium is air and the radiated sound power is calculated by an array of discrete elemental radiators. Several examples are presented to demonstrate the accuracy of the proposed approach. A theoretical performance analysis is finally carried out on a triple panel partition representative of a more complex triple wall aircraft-type window. The testbed design, used for this study, is guided by an effort to quantify sound insulation capabilities of aircraft windows with a specific focus on passenger's protection against noise transmitted through fuselage panels. © 2013 Bentham Science Publishers.


Paletta N.,The Italian Aerospace Research Center | Cristillo D.,The Italian Aerospace Research Center | Belardo M.,The Italian Aerospace Research Center | Marino A.,The Italian Aerospace Research Center | Pecora M.,The Italian Aerospace Research Center
Latin American Journal of Solids and Structures | Year: 2016

This paper presents a methodology for the conceptual design of a Maneuver Load Control system taking into account the airframe flexibility. The system, when switched on, is able to minimize the bending moment augmentation at a wing station near the wing root during an unsteady longitudinal maneuver. The reduction of the incremental wing bending moment due to maneuvers can lead to benefits such as improved pay-loads/gross weight capabilities and/or extended structural fatigue life. The maneuver is performed by following a desired vertical load factor law with elevators deflections, starting from the trim equilibrium in level flight. The system observes load factor and structural bending through accelerometers and calibrated strain sensors and then sends signals to a computer that symmetrically actuates ailerons for reducing the structural bending and elevators for compensating the perturbation to the longitudinal equilibrium. The major limit of this kind of systems appears when it has to be installed on commercial transport aircraft for reduced OEW or augmented wing aspect-ratio. In this case extensive RAMS analyses and high redundancy of the MLC related sub-systems are required by the Certification Authority. Otherwise the structural design must be performed at system off. Thus the unique actual benefit to be gained from the adoption of a MLC system on a commercial transport is the fatigue life extension. An application to a business aircraft responding to the EASA Certification Specifications, Part 25, has been performed. The aircraft used for the numerical application is considered only as a test casestudy. Most of design and analysis considerations are applicable also to other aircraft, such as unmanned or military ones, although some design requirements can be clearly different. The estimation of the fatigue life extension of a structural joint (wing lower skinstringer), located close to the wing root, has been estimated by showing the expected benefit to be gained from the adoption of such a maneuvering load control system. © 2016, Latin American Journal of Solids and Structures. All rights reserved.


Iuliano E.,The Italian Aerospace Research Center | Quagliarella D.,The Italian Aerospace Research Center
53rd AIAA Aerospace Sciences Meeting | Year: 2015

The paper proposes the application of evolutionary-based optimization coupled with physics-based and adaptively-trained surrogate model to the solution of two aerodynamic benchmark problems defined within the AIAA Aerodynamic Design Optimization Discussion Group. The benchmark problems are represented respectively by the drag minimization of the RAE 2822 airfoil in transonic viscous flow and of the NACA 0012 airfoil in transonic inviscid flow. The shape parameterization approach consists of the Class-Shape Transformation (CST) method with a sufficient degree of Bernstein polynomials to cover a wide range of shapes. Mesh convergence is demonstrated on single-block C-grid structured meshes. The in-house ZEN ow solver is used for Euler/RANS aerodynamic solution. Results show that, thanks to the combined usage of surrogate models and intelligent training, optimal candidates may be located in the design space even with limited computational resources with respect to brute force optimization approaches. © 2015 by Emiliano Iuliano. Published by the American Institute of Aeronautics and Astronautics, Inc.

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