Active control of vibration
Categories
Tool adaptor for active vibration control in turning operations
19 June 2023
A tool adaptor with built-in active vibration damping device to dynamically stabilize the turning process is presented in this paper. It can be used in standard CNC-lathes and allows the usage of off-the-shelf tool heads. The vibration compensation system is based on a multilayer piezoactuator that is in collocation with a piezoelectric force sensor. An analogue controller based on the integral force feedback method is used for active damping.
Driving control electronics piezoelectric actuators space applications
19 June 2023
Piezoelectric mechanisms are more and more used in space applications requiring precise positioning functions for scientific payloads or optical functions. Indeed, piezoelectric actuators are generally deemed of being good candidates for driving and control compact mechanisms.
High power force oscillator and drive electronics
19 June 2023
This paper presents the development of one amount the largest piezo actuator ever designed based on low voltage PZT. This actuator is able to provide more than 20kN of force in dynamic operation (60kN in static operation). The purpose of low frequency vibration generation is to improve the quality of parts production in the field of manufacturing and machining process.
Tunable proof mass based on a pendulum structure
6 January 2008
Proof mass dampers are currently used in aircraft structures, but are not active, which introduce performance limitations. Proof Mass Actuators based on spring-mass structures are an interesting technique for active vibration control, but it is difficult to design them for operation below 100 Hz, especially if high dynamic forces are required. The proof of concept of a Tunable Proof Mass Actuator (TPMA) based on a pendulum structure has been assessed into the Mesema FP6 EC project targeting an Helicopter application.
Compact, Efficient and Controllable Moving Iron Actuation Chain for Industrial Application
7 January 2016
In the field of aeronautics, some parts of aircraft engines are tricky and costly to manufacture. In the low pressure turbine very thin pieces obtained by turning require a complex support. The R&D work performed here aims at improving the manufacturing process through the reduction of vibrations and active modification of the clamping conditions. For that purpose, Cedrat Technologies has designed a new innovative Moving Iron Controllable Actuator (MICA), which is embedded on the work-piece support. In the first part, the application goals and the main particularities of the developed MICA200M magnetic actuator are presented. To be easily driven in closed loop, the force is designed to be linear with the current and independent from the interface position. The MICA200M stroke is ±2.5mm and its force constant reaches 11.6N/A for a current range of ±15A
in steady state. The nominal force of 174N for only 1 dm3 size and 3.2kg facilitates the integration and allows acceleration up to 132G in transient operation thanks to reduced 0.25kg mobile mass. In the second part, results of complete experimental characterisation are detailed. Finally, a comparison analysis is done with COTS voice coil actuators and the article concludes with the benefits of the MICA200M.
Self locking MRF actuators for dampers and latches
6 January 2008
MRF actuators are new electromechanical components using Magneto Rheological Fluids (MRF). When submitted to a high enough magnetic field, MRF switch from a liquid to a near solid body. These new developed MRF actuators were developed in order 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.
