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ABC Rotor blades: design, manufacturing and testing
19 June 2023
ABC is the acronym for ‘’Active Blade Concept’’ and represents a 38% Mach scaled model rotor of the Advanced Technology Rotor (ATR) of Eurocopter Germany (ECD, [4]). In contrast to the ATR the model rotor is fully articulated. Specifically, it is equipped with a flap at the trailing edge of each blade, which is driven by a piezoelectric actuator. The ABC project is a cooperation between the French ONERA and the German DLR within the research concept ‘’The Active Rotor’’.
Actionneurs piezoélectriques pour positionnement rapide et précis
19 June 2023
Several classes of low voltage piezo actuators have been developed by CEDRAT TECHNOLOGIES to cover precise positioning needs and / or fast. This paper discusses the ability of these actuators to cover these needs and illustrates this through
various applications (mechanisms, shock absorbers, valves) in the fields of instrumentation, space, aeronautics and automotive.
Active control of vibrations of a space truss using amplified piezoelectric actuators
19 June 2023
The new piezo actuators manufactured by Cedrat Technologies have been developed for the positioning control of space optics but they are spreading widely in various engineering fields such as precise positioning, intelligent control of shapes and generation or control of vibrations. Their ability for the control or active damping of vibrations has been successfully demonstrated at the lab scale in space applications. In a first case, the piezo actuators were used for both for the control of launching vibrations and the positioning control in orbit of a telescope mirror. In a second set of space applications, these piezo actuators have been successfully integrated in a space truss using active tendons for control of micro vibrations, as publicly released at the Industry Space Days (ISD2001, Noordwijk, 9-10 Mai 2001) and as presented in this paper.
Active damping of vibrations applied on ski structures
19 June 2023
Since many years the field of active controls of vibration is growing up and a lot of new applications using smart actuators are developed. In the following study, these concepts are adapted and applied on a general structure of ski to damp the large modes of vibrations keeping the robustness of the control and the static loads during the ride.. Simulations integrating FEM models coupling to electromechanical model were elaborated to obtain the principal performances and to study the stability of the loop.
Active flap device for helicopters based on Cedrat Amplified Piezoelectric Actuators
19 June 2023
A project called RPA (Rotor à Pales Actives) was launched three years ago to study the possible benefits of implementing active trailing edge flaps on a helicopter main rotor. The main objectives of this project are to decrease BVI noise in descent flight and improve the dynamic behavior of the rotor throughout the largest possible flight domain. After a first phase dedicated to the design of the best flap configuration at scale 1, the second phase of the project deals with the design of a wind-tunnel scale model of a rotor equipped with active flaps. An off-the-shelf piezo-electric actuator is used together with a specific patented flap-driving mechanism. Such an active device was tested under centrifugal loads as well as under aerodynamic loads in order to prepare future wind-tunnel tests. The results obtained under centrifugal loads allowed to clear the active device but the aerodynamic testing showed that some improvements were needed. Corresponding modifications are under way to fully clear the active device to be used on a complete rotor model.
ACTUATOR2008 MRF actuators Abstract
19 June 2023
Short Abstract
The MRF actuators are new electromechanical components using Magneto Rheological Fluids (MRF). When submitted to a high enough magnetic field, MRFs switch from a liquid to an almost solid body. The purpose of the new developed MRF actuators is to reach three aims: to offer a blocking force at rest, which can be strongly reduced by applying a current, to provide an electrically- controllable resistive force over a stroke of 30 mm, to perform the control of the force in a very short time, typically in a few milliseconds.
