Publications
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Self-tuning semi-active tuned-mass damper for machine tool chatter suppression
19 June 2023
Tuned mass dampers are simple and efficient devices for suppression of machine tool chatter, which is one of the principal effects limiting productivity in many machining processes. However, their effectiveness depends on a proper tuning of the damper dynamics to the dynamics of the machine. This involves the dynamic characterisation of the machining process, in order to identify the critical resonance frequency, and the possibility of matching the resonance frequency of the damper to frequency. The difficulty of meeting these two requirements has been limiting the use of tuned mass dampers in industrial applications.
Servo piezo tool SPT400MML for fast and precise machining of free forms
19 June 2023
Recent requirements for accuracy and resolution demand higher quality in the machining of precision parts in many industries—such as optics, automotive and aerospace—by free form machining. The required operations are possible by using expensive manufacturing equipment in parallel with several processes such as grinding and polishing. By using a new fast tool servo, the so-called servo piezo tool SPT400MML, driven by a piezoelectric actuator for the precision diamond turning of non-symmetrical surfaces, components can be machined with a fast motion control of the tool (diamond or carbide).
Ski embbeded piezo system
19 June 2023
Since many years, the field of active control of vibrations has been growing up and many new applications using smart actuators have been developing. In 2003, CEDRAT TECHNOLOGIES in collaboration with SKI ROSSIGNOL initiated a project supported by ESA where these concepts (smart material and active control of vibration) were adapted and applied on a ski structure. The project aim was to damp the large modes of vibrations keeping the robustness of the control and the static loads during the ski ride.
Point Ahead Mechanism for Deep Space Optical Communication Development of a New Piezo-Based Fine Steering Mirror
19 June 2023
The purpose of this paper is to present the development of a novel tip-tilt mechanism, with integrated optics, designed for the JPL Deep Space Optical Communication (DSOC) module of the upcoming Psyche mission (2022 launch). This paper presents the design, assembly and tests of the produced models. Regarding the design phase, an emphasis was put on the mirror calculations to ensure that the required flatness would be maintained after integration, and that the part would withstand the thermal/mechanical environment. The actual optical measurements performed after assembly are also presented. The qualification results for a new alpha-case removal process for titanium parts are presented. Tests results are especially interesting
regarding the temperature behavior of the mechanism, impact on the stroke, and strain gage sensor feedback.
Progress In Magnetostrictive Sonar Transducers
19 June 2023
Continous interest from the French Navy (DRET and CERDSM) has permitted significant improvements to magnetostrictive transducers in order to produce low-frequency high-power sonar sources. These improvements can be appreciated by looking at three transducers.
Pulsed air high performances valves improve aerodynamic flow over airplane wings
19 June 2023
The objective of the European Cleansky project is to develop new technologies for future aircraft enabling a 20-30% fuel burn reduction and related CO2 emissions and a similar reduction in noise levels compared to current aircraft. One of the ways to reach this goal is to improve the aerodynamic performances of current high lift devices. Active flow control is unanimously seen as the best mean to reach this objective. By suppressing flow separation and/or delaying stall, active flow control will increase wing aerodynamic performances. The partnership between CTEC and ONERA in the framework of the VIPER project has led to the design, manufacturing and test of an innovative pulsed jet actuator based on a CTEC amplified piezo-actuator (APA). Its aim is to provide a pulsed sonic jet up to 500Hz with a mass flow around 34 g/s through a slot 1mm wide and 80mm long. Coupled with CTEC SA75D switching power amplifier this actuator produces the expected sonic jet with an electrical consumption around 40W thanks to energy recovery. The results of the actuator characterisation (mechanical, fluidic) are presented in this paper.
