ONGOING ACTIVITIES

Development of a comprehensive numerical tool for vibration and acoustic analysis of finite-size multilayered composite panels, based on accurate and efficient sublaminate Ritz models with variable-kinematics capabilities. Classical laminated to more advanced sandwich configurations involving frequency-dependent viscoelastic materials and piezoelectric materials can be studied within a unified modeling framework. The 2-D plate model can be arbitrarily defined with different kinematic refinements in different thickness subregions, so that the accuracy and computational effort can be calibrated and balanced according to the case under study.
Development of an advanced transfer matrix method (TMM) embedding spatial windowing techniques to predict the transmission loss of helicopter trim panels with anisotropic and heterogeneous layers. The methodology applies to planar media with in-plane periodicity. An appropriate through-the-thickness transfer matrix is derived by manipulating the dynamic stiffness matrix related to a finite element (FE) model of the unit cell constituting the periodic plate. The proposed combination of TMM and FE modeling represents a versatile and efficient acoustic tool, overcoming the limitations of homogeneous equivalent models.
Design and implementation of active devices and systems on glass windows with noise reduction capabilities. The effort is focused on studying efficient solutions aimed at vibrating the window in a pattern counter to the vibrations caused by the ambient noise, essentially turning the window surface into a noise-canceling speaker.
Multidisciplinary modeling and control of telescope adaptive mirrors. The design and active control of adaptive telescope mirrors requires a multidisciplinary approach, ranging from the simulation of the thin fluid film entrapped between the mirror and its reference body to the magnetic and electric characterization of the actuation and sensor system. AVLab pioneered, together with Osservatorio Astrofisico di Arcetri, Microgate and ADS International, the secondary mirror contactless solution. It is now actively working on the development of advanced simulation models and new control schemes. It is also involved in the simulation of the E-ELT M4 adaptive unit and of the GMT Adaptive Secondary Unit.
AVLab participates to the PoliMi Sound and Vibration Laboratory (PSVL), the reference research structure of Politecnico di Milano in vibroacoustics, flow acoustics, applied acoustics, noise and vibration control, sound processing, musical acoustics, psychoacoustics, music information retrieval.

FUTURE PLANS

AVLab plans to use the simulation and prediction tools under development to perform multidisciplinary optimizations of complex structures, accounting for acoustic, low frequency vibrations and for nonlinear structural constraints.
Topology optimization techniques are going to be used to design tailored band-gap meta-materials.
AVLab plans to investigate if - and how - the existing adaptive mirror technology can be adapted for the control of large space structures and of flexible structures with negligible damping.

ERC KEYWORDS

PE7-3 Simulation engineering and modelling
PE7-1 Control Engineering
PE9-15 Space Sciences
PE8-1 Aerospace Engineering

FREE KEYWORDS

Active and adaptive optics
Massive structural control