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Vibration energy harvesting in aircraft using piezoelectric actuators
19 June 2023
In the aicrft vehicle, a part of the produced energy is transformed into mechanical vibration energy losses. This rue is more than ever true when the need for electrucal energy is a crucial problem. So, systems which are able to transform the mechanical energy in a scavenged electrical energy are very interesting.
Electro-fluidic components based on smart materials for aircraft electro-hydraulic
19 June 2023
In the context of a more electrical aircraft, in order to explore the feasibility of non usual solutions, electro-fluidic components based on smart materials and new Electro-Hydraulic-Actuators (EHA) concepts, based on active valves and magnetostrictive vibrating pump, have been studied. Active valves based on different magnetostrictive and piezoelectric actuators have been designed, realised, tested and compared. The magnetostrictive version uses a new Amplified Magnetostrictive Actuator (AMA) based on a stack of Giant Magnetostrictive Materials (GMM) and placed inside an elliptical amplification ring.
Viscoelastic properties of the ferret brain measured in vivo at multiple frequencies by magnetic resonance elastography
19 June 2023
Characterization of the dynamic mechanical behavior of brain tissue is essential for understanding and simulating the mechanisms of traumatic brain injury (TBI). Changes in mechanical properties may also reflect changes in the brain due to aging or disease. In this study, we used magnetic resonance elastography (MRE) to measure the viscoelastic properties of ferret brain tissue in vivo.
Voice coil actuators for two MTG instruments
19 June 2023
While Cedrat Technologies has been active in space for more than 20 years with piezoelectric mechanisms, we have also been increasingly involved over the last few years in the development of magnetic actuators for space projects. In this paper, a focus is made on the case of magnetic actuators that are developed in the frame of the Meteosat Third Generation (MTG) project. The first one is the Scan Assembly (SCA) actuated by Rotating Voice Coil Motors (RVCM) for the East/West (E/W) axes and the North/South (N/S) axes developed in collaboration with Sener and the second one is the Voice Coil Motor (VCM) developed in collaboration with CSEM for the Corner Cube Mechanism (CCM)
Wind-tunnel tests of a helicopter rotor with active flaps
19 June 2023
Within the frame of a project called DTP RPA (DĂ©veloppement Technique Probatoire Rotor Ă Pale Active), also known as Active Blade Concept, carried out in cooperation between ONERA, Eurocopter, DLR and Eurocopter Deutschland, a four-bladed Mach-scaled rotor was tested in December 2005 in ONERA S1 Modane wind-tunnel. The main objective of this test was to validate the concept of using active flaps located on the trailing edge of the blades of the main rotor of a helicopter to decrease the vibration level generated by this rotor.
Robustness of SHM techniques based on lamb waves
19 June 2023
Required improvements of piezoelectric elements actuation and measurement system efficiency and robustness are introduced as a critical feature for structural health monitoring (SHM) applications. An electronic module (Lamb wave detection system: LWDS) allowing to use each piezoelectric element in an array either in emission or reception mode is presented. The high commutation rate between these two states, for each transducer separately, is a key enhancement for SHM methods. The robustness of the sensor integration is also studied considering the patches size and bonding method. Coupled dispersion curve are introduced Comparison of FEM simulation and experiments of the piezo-electric coupling are presented. This work takes part of the H2020 REMAP project about adaptive aircraft maintenance planning.
