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The purpose of this study is to investigate a new and innovative sandwich material evaluating its capability for use in space habitat structural components in deployable and foldable configurations. The main habitat requirements were considered in the preliminary design of a typical space outpost, proposing a preliminary architecture.

The stiffness properties of the innovative sandwich (MAdFlex ®) were evaluated using numerical and experimental investigations. Four-point bending tests were performed for complete sandwich characterization. Numerical FE simulations were performed using typical material properties and performance. The application to a space habitat main structure as a basic material has also been discussed and presented.

MAdFlex basic stiffness performances have been determined considering its double behavior: sufficiently stiff if loaded in a specific direction, flexible if loaded in the opposite direction and enhanced folding performance. Successful application to a typical space habitat confirms the validity and convenience of such a material in designing alternative structures.

The innovative material demonstrates wide potential for structural application and design in demanding space situations under operating conditions and in stored ones at launch.

Several simple deployable structural components can be designed and optimized both for the space environment and for the more traditional terrestrial applications.

Simplification in structural design can be derived from deployable low-weight items.

Innovative customized material in sandwich configuration has been proposed and investigated with the aim to demonstrate its potentiality and validity in alternative design architecture.

The purpose of the research activity is to identify the best configuration of piezoelectric (PZT) elements for a typical condition of wing aeroelastic instability. The attention is mainly focused on the flutter behavior of the structure. However, the model can be extended with low-impact adjustments to other loading conditions.

The dynamic system consists of a thin-walled beam, whose longitudinal faces are perfectly bonded by two PZT layers and it is excited by the aerodynamic forces to assume a simple harmonic oscillation motion. The equations of motion are obtained using an energy approach by applying the extended Hamilton principle in conjunction with the Ritz method for modal approximation. The external forces acting on the system are modeled according to the Theodorsen derivation.

The flutter speed and the power generated from flutter oscillations can be increased by acting on the length of the PZT elements. The results show that the model with the beam substrate totally covered by the PZT in its longitudinal direction is more effective for low electrical resistance, whereas for high resistance values, the beam substrate that is partially covered provides the best results. Furthermore, both flutter postponement and energy harvesting functions can be maximized by properly choosing the beam stiffness ratio.

Depending on the parameter we want to maximize, that is, the flutter speed or the energy harvested, it is possible to identify the best system configuration from the analysis presented in this paper.

The originality of the work appears in the sensitivity study performed on a three-dimensional piezo-aeroelastic fluttering wing, whose optimal behavior in terms of flutter postponement and power generation is analyzed using two distinct parameters, the beam stiffness ratio and the PZT length.

This study aims to analyse slender thin-walled anisotropic box-beams. Fiber-reinforced laminated composites could play an important role in the design of current and future generations of innovative civil aircrafts and unconventional unmanned configurations. The tailoring characteristics of these composites not only improve the structural performance, and thus reduce the structural weight, but also 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 proper structural beam scheme, which is a modification of a previous first-level approximation scheme, has been adopted. The effect of local laminate stiffness has been investigated to check the possibility of extending the analytical approximation to different structural configurations. The equivalent stiffness has been evaluated for both the case of an isotropic configuration and for simple thin-walled laminated or stiffened sections by introducing classical thin-walled assumptions and the classical beam theory for an equivalent system. Coupling effects have also been included. The equivalent analytical and finite element beam behaviour has been determined and compared to validate the considered analytical stiffness relations that are useful in the preliminary design phase.

The work has analyzed different configurations and highlighted the effect of flexural/torsion couplings and a local stiffness effect on the global behaviour of the structure. Three types of configurations have been considered, namely, a composite wing box configuration, with and without coupling effects; a wing box configuration with sandwich and cellular constructions; and a wing box with stiffened panels in a coupled or an uncoupled configuration. An advanced aluminium experimental test sample has also been described in detail. Good agreement has been found between the theoretical and numerical analyses and the experimental tests, thus confirming the validity of the analytical relations.

The equivalent beam behaviour that has been determined and the stiffness calculation procedure that has been derived could be useful for future dynamic and aeroelastic analyses.

The article presents an original derivation of the sectional characteristics of a thin-walled composite beam and a numerical/experimental validation.