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The aeroelastic design of highly flexible wings, made of extremely light structures yet still capable of carrying a considerable amount of non-structural weights, requires significant effort. The complexity involved in such design demands for simplified mathematical tools based on appropriate reduced order models capable of predicting the accurate aeroelastic behaviour. The model presented in this paper is based on a consistent nonlinear beam model, capable of simulating the unconventional aeroelastic behaviour of flexible composite wings. The partial differential equations describing the wing dynamics are reduced to a dimensionless form in terms of three ordinary differential equations using a discretization technique, along with Galerkin's method. Within this approach the nonlinear structural model an unsteady indicial based aerodynamic model with dynamic stall are coupled.

The aim of this work is to apply an innovative adaptive ℒ1 techniques to control flutter phenomena affecting highly flexible wings and to evaluate the efficiency of this control algorithm and architecture by performing the following tasks: i) adaptation and analysis of an existing simplified nonlinear plunging/pitching 2D aeroelastic model accounting for structural nonlinearities and a quasi-steady aerodynamics capable of describing flutter and post-flutter limit cycle oscillations, ii) implement the ℒ1 adaptive control on the developed aeroelastic system to perform initial control testing and evaluate the sensitivity to system parameters, and iii) perform model validation and calibration by comparing the performance of the proposed control strategy with an adaptive back-stepping algorithm. The effectiveness and robustness of the ℒ1 adaptive control in flutter and post-flutter suppression is demonstrated.

The hydrogen and fuel cell power based technologies that are rapidly emerging can be exploited to start a new generation of propulsion systems for light aircraft and small commuter aircraft. Different studies were undertaken in recent years on fuel cells in aeronautics. Boeing Research & Technology Centre (Madrid) successfully flew its converted Super Dimona in 2008 relying on a fuel cell based system. DLR flew in July 2009 with the motor-glider Antares powered by fuel cells. The goal of the ENFICA-FC project (ENvironmentally Friendly Inter City Aircraft powered by Fuel Cells - European Commission funded project coordinated by Prof. Giulio Romeo) was to develop and validate new concepts of fuel cell based power systems for more/all electric aircrafts belonging to a “inter-city” segment of the market.

Next generation of composite civil aircrafts and unconventional configurations, such as High Altitude Long Endurance HALE-UAV, exhibit aeroelastic instabilities quite different from their rigid counterparts. Consequently, one has to deal with phenomena not usually considered in classical aircraft design. Alternative design criteria are needed in order to maintain the safety levels imposed by the regulations and required for certification. The A2-Net-Team project aims to build a multi-disciplinary network of researchers with complementary expertise to develop analytical methods used for a better understanding and assessment of the factors contributing to the occurrence of critical aeroservoelastic instabilities. Along with modeling and numerical investigations a test article will also provide the opportunity to modify and calibrate theoretical models, to highlight and explore their limits, to recommend the necessary modifications and future pertinent investigations.

In the second half of the 2004, Thales Alenia Space - Italia started an Advanced Live Support Research & Development program denominated Recyclab, on own funding. The main objectives of the Recyclab program are: To determine the actual development needs and possibilities in the international scenario in the Advanced Life Support field To develop new technologies for the regeneration of the main resources in exploration missions (water, air, waste) To test the technologies developed in closed loop in an integrated system.

ASA (Advanced Structural Assembly) is an Italian Space Agency (ASI) technological development program which has the purpose to investigate and improve the knowhow on fundamental technologies relevant to the field of the space re-entry vehicles. A wing segment collecting different experiments will be tested in the Plasma Wind Tunnel (PWT) available at the Scirocco facility. One of the technologies under investigation is the active cooling applied to a wing leading edge element. That design solution is challenging both for manufacturing and for thermal-hydraulic aspects. A dedicated analysis campaign was performed at design level and a development test was carried out on a representative “breadboard” to verify the basic assumptions before the manufacturing of the final technological demonstrator which will be tested in the Plasma Wind Tunnel facility.

One of the major technological issues for a planetary entry mission is related to the identification of thermal protection materials compatible with the predicted Environmental Heat Load for the different exposed reentry vehicle surfaces. According to the Apollo mission experience, the maximum heat flux experienced by a vehicle returning from a lunar mission is about 5 MW/m2. This value is not compatible with the reusable TPS developed for the vehicle returning from LEO mission and ablative materials have to be introduced. The paper describes a preliminary investigation on the compatibility of the existing ablative material with the Environmental heat load calculated in the frame of the Moon & Mars Human Mission Re-entry Technologies study for both Biconic and Slender Body vehicle shape.

The on-orbit performance verification of the functions constituting a Space Manned System is one of the critical points of space projects. During phase C/D of Node 2 & 3 and ATV Space station modules, the Alcatel Alenia Space - Italia approach for the verification of the design requirements related to the correct air distribution inside the Module habitable volume was to use a CFD virtual mock-up, derived by CAD models. These models were correlated with existing on ground ventilation tests and were extensively used during the project phase to evaluate the impact on the relevant ventilation requirements of possible internal module layout changes and item relocations. This paper describes the developed tool capability and presents the results obtained in support to the Assembly, Integration and Test (AIT) phases.

Bepi Colombo is an ESA mission targeted to the exploration of Mercury with two spacecraft, a Mercury Polar Orbiter (MPO) provided by Europe and a Mercury Magnetospheric Orbiter (MMO) provided by Japan. The Mission is lead by Astrium Friedrichshafen, with Thales Alenia space Torino responsible for the MPO thermal design. The MPO is a 3-axis stabilized scientific spacecraft in Mercury polar eccentric orbit, with altitude from 400 to 1500 km, with one face planet oriented and pointing Nadir, and housing the apertures of the observation P/L. Studies for this mission were initiated in the late 90ies, and pointed out that one of the main design drivers for the MPO was the thermal environment in orbit, due to the combination of high solar constant (up to 10 solar constants on Earth), infrared and albedo from the planet (maximum IR up to about 4 terrestrial solar constants, albedo up to about 1).

A significant effort has been conducted in 2007 by TAS-I (Thales Alenia Space Italia) to adequately prepare the Engineering Support to Mission 1E (Columbus installation) and subsequent stages for ECLSS operational support. This activity has been conducted both in the frame of the Engineering Support Team (EST) responsibilities and in the frame of the Columbus/Payloads integrated Stage analyses. Among the various tasks, two has been identified as outstanding: The building of a Computional Fluid Dynamics (CFD) model of Columbus cabin for ventilation analyses. The building of a tool for the calculation of cabin air volume flow rate from air loop telemetry data (primarily fans dp and input current) This paper describes in detail the above mentioned activities by pointing the attention on the critical aspects to be faced and the utilized techniques, taking also into account 1E mission lessons learned, and future developments.

The market pressure towards compression of costs and schedule time affects all the programs activities. For the campaigns of thermal verification in particular, this trend results in the recurring request for shorter and inexpensive test verification campaigns. This paper presents the Thales Alenia Space-Italia experience in the field of the thermal balance tests, by comparing the test philosophies and approaches followed on various Navigation and Earth Observation satellites, for which TAS-I was fully responsible of the thermal control and of the relevant verification. The objectives of the comparison are to highlight the critical choices and the relevant lessons learnt in the test definition process, and to promote the standardization and optimization of the thermal verification campaigns, with particular regard to: Evaluation of the uncertainty confidence level and of its evolution along the program cycle.

In the frame of the space food production research activities conducted in the Thales Alenia Space Italia (TAS-I) Advanced Life Support Research and Development laboratory (RecycLAB, [6]), and with the contribution of a degree thesis developed in collaboration with the Politecnico of Torino, a rack-like facility for ground research on Life Support Systems based on Plants has been designed, developed, integrated, verified and tested in TAS-I. The new facility, called EDEN EPISODE 2, is a significant evolution of a previous TAS-I project (EDEN EPISODE 1) and takes benefit from other lower size TAS-I demonstrators (CUBE). It aims at realizing a completely closed and controlled environment for crop production, while a mobile lighting panel allows to maximize the delivered light in each phase of the plant life cycle. Hydroponic and aeroponic techniques have been implemented in the project for nutrient delivery to the plant roots.

This paper describes a multidisciplinary strategy for designing and preliminary sizing of advanced life support systems for space applications, ranging from open-loop solutions to more advanced physico-chemical and bioregenerative systems. The strategy, based on the use of transient simulation, heuristic techniques, and realtime integrated control has been implemented into a Matlab-Simulink tool, letting large numbers of system configurations to be rapidly tested and evaluated. The tool has been built aiming to easy expandability and updating. The optimization approach for selection of design solutions is based on a MOPSO (Multi Objective Particle Swarm Optimization) algorithm, which presented optimum convergence properties. Different test cases have been considered, both to evaluate tool's capacity to select proper life support system configurations, and to verify sizing accuracy.

The Atmospheric Revitalization System (ARS) provides carbon dioxide removal, trace contaminant control, and gas constituent analysis. In this field, the interest of RecycLAB [5], the TAS-I Advanced Live Support Research & Development laboratory is directed to trace gas contaminants removal and monitoring. During manned space mission, the decontamination of cabin or rack air after contingency events such as fire or pyrolysis is a priority for the crew safety. In this paper, basic zeolites, obtained by impregnation of common zeolites with a basic oxide, are used to remove acid gas contaminants from air stream. A multi-functional system, able to accommodate reactors of different shape, characteristics and set-up, is used at this purpose. This breadboard, called ZEUS (Zeolites for an Environmental-control Unit in Space), is made of AISI 316L stainless steel and consists of a closed loop, in which the inner volume is completely isolated from the external environment.

An electronic instrument for the measurement of fuel consumption in reciprocating internal combustion engines for light aircraft has been designed, manufactured and tested. The operating principle of the measuring device is based on the simple, theoretically supported and experimentally verified observation that the fuel mass flow rate is almost exactly proportional to the product of the intake manifold air pressure “pc” and the engine revolution speed “n”. Therefore, only two sensors are needed, and no fuel pipe cutting is required for installation and operation. This feature represents a major point in favor of simplicity, reliability and safety. The aim of the instrument is to provide a fuel consumption indication which can be used during cruising. The instrument is not intended as a replacement for the usual on-board fuel level gauge, but can be used to integrate the flight information with the overall and instantaneous fuel consumption data.

Future generations of civil aircrafts and unconventional unmanned configurations demand for innovative structural concepts to improve the structural performance, and thus reduce the structural weight, but also to allow possible material couplings to be made. Static and dynamic aeroelastic stability can be altered by these couplings. It is therefore necessary to use an accurate and computationally efficient beam model during the preliminary design phase. A stiffened box, made of isotropic material, but with the stiffeners oriented so that they originate the expected bending/torsion coupling, is considered in the present work. The overall equivalent bending, torsional and coupled stiffness is derived by means of homogenization of the shell skin and of the stiffener plate stiffness. A new equivalent homogeneous orthotropic material is determined and introduced into the equivalent plate configuration.

Innovative aircraft design studies have noted that uncertainty effects could become significant and greatly emphasized during the conceptual design phases due to the scarcity of information about the new aero-structure being designed. The introduction of these effects in design methodologies are strongly recommended in order to perform a consistent evaluation of structural integrity. The benefit to run a Robust Optimization is the opportunity to take into account uncertainties inside the optimization process obtaining a set of robust solutions. A major drawback of performing Robust Multi-Objective Optimization is the computational time required. The proposed research focus on the reduction of the computational time using mathematic and computational techniques. In the paper, a generalized approach to operate a Robust Multi-Objective Optimization (RMOO) for Aerospace structure using MSC software Patran/Nastran to evaluate the Objectives Function, is proposed.

An accurate aeroelastic assessment of powered HALE aircraft is of paramount importance considering that their behaviour contrasts the one of conventional aircraft mainly due to the use of high aspect-ratio wings with distributed propulsion systems. This particular configuration shows strong dependency of the wing natural frequencies to the propulsion distribution and operating conditions. Numerical and experimental investigations are carried out to better understand the behaviour of flexible wings, focusing on the effect of distributed electric propulsion systems. Several configurations are investigated, including a single propulsion system using an engine pod (a weight with embedded electric motor, a propeller, and the wing-attached structure) installed at selected spanwise positions, and configurations with two and three propellers.

This paper aims to show how it is possible to blend a Tool Chain approach with a Model Based Engineering Environment approach during preliminary phases of a space project. Attention is not focused on the whole spacecraft lifecycle but on a preliminary phase that is very helpful in itself to test methodology, technologies and processes. This blended model may allow for cost reduction and reduced development times along the supply chain whereas there are heterogeneous IT systems and tools. The aim of this work has been to make engineering data exchange among different engineering groups easier whilst guaranteeing compliancy to a common spacecraft data model. This methodology has been applied to a test case comprising the preliminary design of a Pressurized Lunar Rover (PLR).

This paper deals with the ground testing of the technological demonstrator of the innovative remotely controlled ETF airship1. The testing activities are intended to validate the flight control system of the ETF, which is based on the thrust vectoring technology and represents one of the major innovations of the ETF design, together with the airship architecture. A research team of the Aeronautical and Space Department of the Polytechnic of Turin, in collaboration with Nautilus, a small Italian private company, has been working since a few years on the ETF (Elettra Twin Flyers). This airship is remotely-piloted, with high maneuverability capabilities and good operative features also in adverse atmospheric conditions2. The Nautilus new concept airship features architecture and appropriate command system, which should enable the vehicle to maneuver in forward, backward and sideward flight and hovering with any heading, both in normal and severe wind conditions.