On-orbit modal identification for vibration suppression of flexible aerospace structure using reaction wheel actuator

AbstractThe paper presents an innovative method of solving the problem of vibration suppression during milling of large-size details. It consists in searching for the best conditions for clamping the workpiece based on a rapid modal identification of the dominant natural frequencies only and requires repetitive changes in the tightening torque of the clamping screws. Then, by estimating the minimum work of the cutting forces acting in the direction of the width of the cutting layer, it is possible to predict the best fixing of the workpiece. Application of the method does not require the creation and identification of a computational model of the process or preliminary numerical simulations. The effectiveness of this method was confirmed by the evaluation of the Root Mean Square (RMS) of the vibration level in the time domain observed during the actual face milling process. The worst results were obtained for the configuration of supports tightened with a torque of 90–110 Nm, and the best—with a torque of 50 Nm.

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A Method of Predicting The Best Conditions for Clamping a Large-Size Workpiece in Order To Reduce Vibrations in The Milling Process

10.21203/rs.3.rs-741664/v1 ◽

2021 ◽

Author(s):

Krzysztof J. Kaliński ◽

Natalia Stawicka-Morawska ◽

Marek A. Galewski ◽

Michał R. Mazur

Keyword(s):

Natural Frequencies ◽

Vibration Suppression ◽

Milling Process ◽

Face Milling ◽

Modal Identification ◽

Vibration Level ◽

Large Size ◽

Innovative Method ◽

The Time Domain ◽

Minimum Work

Abstract The paper presents an innovative method of solving the problem of vibration suppression during milling of large-size details. It consists in searching for the best conditions for clamping the workpiece based on a rapid modal identification of the dominant natural frequencies only and requires repetitive changes in the tightening torque of the clamping screws. Then, by estimating the minimum work of the cutting forces acting in the direction of the width of the cutting layer, it is possible to predict the best fixing of the workpiece. Application of the method does not require the creation and identification of a computational model of the process or preliminary numerical simulations. The effectiveness of this method was confirmed by the evaluation of the Root Mean Square (RMS) of the vibration level in the time domain observed during the actual face milling process.

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Structural Vibration Suppression Using the Piezoelectric Sensors and Actuators

Journal of Vibration and Acoustics ◽

10.1115/1.1523891 ◽

2003 ◽

Vol 125 (1) ◽

pp. 109-113 ◽

Cited By ~ 7

Author(s):

Y. Y. Lee ◽

J. Yao

Keyword(s):

Time Domain ◽

Vibration Suppression ◽

Modal Identification ◽

Piezoelectric Sensors ◽

Sensors And Actuators ◽

Simply Supported ◽

Piezoelectric Sensors And Actuators ◽

Curved Panel ◽

Identification Technique ◽

The Time Domain

An experimental study for the active vibration control of structures subject to external excitations using piezoelectric sensors and actuators is presented. A simply supported plate and a curved panel are used as the controlled structures in two experiments, respectively. The Independent Modal Space Control (IMSC) approach is employed for the controller design. In order to increase the adaptability, the time-domain modal identification technique is incorporated into the controller to real-time update the system parameters. The adaptive effectiveness of the time-domain modal identification technique is tested by fixing an additional mass on the simply supported plate to change its structural properties. The vibration suppression performances of the controller are 5.7 dB and 10.8 dB for the simply-supported plate with/without the mass subject to a chirp sine excitation, respectively. For the experiment of the curved panel subject to a sinusoidal excitation, the vibration attenuation of the control scheme is 5.0 dB even the control circuit is subject to some noise generated by electrical and magnetic interferences.

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