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The flapping flight is advantageous for its superior maneuverability and much more aerodynamically efficiency for the small size UAV when compared to the conventional steady-state aerodynamics solution. Especially, it is appropriate for the Micro-air-vehicle (MAV) propulsion system, where the flapping wings can generate the required thrust. This paper investigated such solution, based on the piezoelectric patches, which are attached to the flexible plates, in combination with an appropriate amplification mechanisms. The numerical and experimental flow analyses have been carried out for the piezoelectric flapping plate, in order to characterize the fluid structure interaction induced by the swinging movement of the oscillating plate.

This paper presents a structural analysis of an engine chassis for a disc-shaped airship demonstrator. The objective was to verify such design solutions for application in the European Union's MAAT (Multibody Advanced Airship for Transport) project. In many airship designs, the engines are attached to the airship frame, located inside the balloon, in order to allow for thrust vector control. These airships have aerodynamic control surfaces to improve maneuverability. For the demonstrator, three engines are considered, with a non-rigid internal structure for their attachment. The engines are located on a horizontal plane (the symmetry plane of the balloon), with two lateral engines and one in front of the balloon. The chassis installation allows the engines to be attached either directly to the exterior envelope by using Kevlar connections, or to the central structural pipe. This chassis design has a simple construction, compared to typical structures addressed in the literature.

In order to optimise the vibro-acoustic behaviour of panel-like structures in a more systematic way, accurate structural models are needed. However, at the frequencies of relevance to the vibro-acoustic problem, the mode shapes are very complex, requiring a high spatial resolution in the measurement procedure. The large number of required transducers and their mass loading effects limit the applicability of accelerometer testing. In recent years, optical measuring methods have been proposed. Direct electronic (ESPI) imaging, using strobed continuous laser illumination, or more recently, pulsed laser illumination, have lately created the possibility to bring the holographic testing approach to the level of industrial applicability for modal analysis procedures. The present paper discusses the various critical elements of a holographic ESPI modal testing system.