Active control of vibration
Categories
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.
Semi-passive vibration control technique via shunting of Amplified Piezoelectric Actuators
12 January 2016
The objective of this paper is to provide results of an experimental and analytical investigation of Amplified Piezoelectric Actuators (APA) as vibrational isolator in a configuration of a mechanical Single Degree of Freedom system. The investigation is aimed at assessment of the mechanical properties modification ability via shunting techniques. The investigation consist of a phenomenological modelling of the APAs considered as generators and experimental verification of the vibrational energy dissipation ability in frequency domain. The results obtained during this investigation reveal that it is feasible to receive more than 20 dB reduction of the displacement amplification in the resonant range. Moreover, three tested examples of APA reveal up to 9 % of resonant frequency shift due to proper adjustment of the electronic shunting circuit, which is an encouragement for further analyses towards application of the APAs in semi-passive vibration control applications.
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.
Very Compact Integration of an Ultra-Low Vibration Platform for Space Cryocoolers Using Miniature High Frequency Actuators
19 June 2023
Air Liquide advanced Technologies in collaboration with Cedrat Technologies and SMAC has performed a study of a compact vibration control platform for mechanical cryocoolers. This solution has been proposed as an alternative approach to cryocooler integration with respect to suspended systems that must be mechanically locked during the launch phase. This system allows significant reduction of the platform’s physical size and mass.
