The researches performed during last ten years in the field of adaptive or ’smart’ structures, including morphing, are mainly focused on the embedding of many already-mature smart structure concepts actuators, sensors, materials, etc..), coupled with novel shaping techniques, into a single aircraft to produce emarkable improvements of the global performances.
This improvement is general, and can be related to different disciplines. The use of embedded actuators can improve the aerodynamic/aeroelastic/acustic response of the structures. Finally, the use of embedded mechanism (mainly based on new materials or new structural concepts) allows to adapt the shape of the wing to optimize its performances during the flight.
Researches related to morphing carried out in the ASDL Lab are mainly based on the concept of compliant structures where the structure is smoothely deformed by an ad hoc design of the distributed structural stiffness. The obained structures are typically hingeless, continuous, able to guarantee a smooth deformed shape and not subject to friction and backlash.
Applications developed during last years are related to both Leading and Trailing edge control surfaces. The images on the left show the 2D models of LE and TE morphing in both undeformed and deformed (morphed) configuration.
The approach is based on the adoption of morphing ribs able to modify the shape of the wing, basically the camber, in a continuous way without any gap typical of classical control surfaces. The design of morphing ribs requires a compromise between the load carry capability together with the ability to change the external shape. For this reason, a two-level optimization procedure has been developed. In the first level the optimal airfoils shape s determined, trying to match the best aerodynamic performance and at the same time to inimize the deformation energy related to the airfoil skin; in the second optimization level the ptimal internal structure is designed by combining a compliant structures analysis and design ool with a genetic-based optimization solver.
The application of this technology has been validated both on numerical simulation models as well on experimental small and large scale demonstrators, like the one shown on the left, representing a full scale, reduced span, LE morphing designed and successfully tested during CS2-AIRGREEN2 EU project in 2022.
The activities related to morphing structures have been developed in the framework of different EU projects, such as:
Active Aeroelastic Aircraft Structures - 3AS (FP5, 2003-2006)
SMORPH, funded by European Science Fundation (ESF, 2007-2010)
Smart Intelligent Aircraft Structures - SARISTU (FP7, 2011-2016)
NOVEl air vehicle configurations: from fluttering wings to MORphing flight - NOVEMOR (FP7, 2011-2014)
Cleansky 2 - AIRGREEN2 project (2014-2022)
Clean Aviation - HERWINGT project (2023-2025)
V.Cavalieri