VIBRATION SUPPRESSION USING A LASER VIBROMETER AND PIEZOCERAMIC PATCHES

This paper develops H2 modified positive position feedback (H2-MPPF) and H∞-MPPF controllers for spatial vibration suppression of flexible structures in multimode condition. Resonant vibrations in a clamped–clamped (c–c) and a cantilever beam are aimed to be spatially suppressed using minimum number of piezoelectric patches. These two types of beams are selected since they are more frequently used in macro- and microscale structures. The shape functions of the beams are extracted using the assumed-modes approach. Then, they are implemented in the controller design via spatial H2 and H∞ norms. The controllers are then evaluated experimentally. Vibrations of multiple points on the beams are concurrently measured using a laser vibrometer. According to the results of the c–c beam, vibration amplitude is reduced to less than half for the entire beam using both H2- and H∞-MPPF controllers. For the cantilever beam, vibration amplitude is suppressed to a higher level using the H2-MPPF controller compared to the H∞-MPPF method. Results show that the designed controllers can effectively use one piezoelectric actuator to efficiently perform spatial vibration control on the entire length of the beams with different boundary conditions.

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A nonlinear disturbance rejection vibration control for an all-clamped piezoelectric panel

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209346 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 403-411

Author(s):

Shengquan Li ◽

Chaowei Zhu ◽

Juan Li ◽

Qibo Mao

Keyword(s):

Vibration Control ◽

Real Time ◽

Vibration Suppression ◽

Control Method ◽

Active Vibration Control ◽

Laser Vibrometer ◽

Modeling Uncertainties ◽

Acceleration Feedback ◽

Active Vibration ◽

Nonlinear Extended State Observer

Considering the internal and external disturbances in actual engineering structure, a composite active vibration control method is proposed for an all-clamped piezoelectric panel. First, the theoretical modal analysis and laser vibrometer are employed to obtain the natural frequency and mode shape of the panel, for reasonable arrangement of actuator and accelerometer. Second, a nonlinear extended state observer is introduced to estimate the total disturbances, i.e., modeling uncertainties, high-order harmonics, coupling and external excitations. Third, the estimated value is used to compensate and attenuate the influence of the total disturbances in real time. In addition, the feedback controller based on the proportional differential and acceleration feedback method is designed to enhance the vibration suppression performance of the whole system. Finally, a semi-physical platform is built in MATLAB/Simulink real-time environment with the NI-PCIe6343 acquisition card to verify the effectiveness and superiority of the proposed method.

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Analysis on Vibration Characteristics of Air Film Damping with Open Boundaries

Mathematical Problems in Engineering ◽

10.1155/2019/1414872 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10

Author(s):

Hong Zhang ◽

Dong-ze Cui ◽

Ying-jie Jiao ◽

Xi Chen

Keyword(s):

Vibration Suppression ◽

Laser Vibrometer ◽

Skin Thickness ◽

Vibration Exciter ◽

Suppression Effect ◽

Open Boundaries ◽

Thin Skin ◽

Dissipation Equation ◽

Air Film ◽

Made In

Air film damping (AFD) has been a research focus for the fatigue damage suppression problem of aeroengine blade decades ago; however significant progress has not been made in the past decade. In this paper, we present a theoretical model and experimental analysis about this technology. The dissipation mechanism of the AFD is established by assumption that the viscous gas inside the thin air film is Poiseuille flow and the energy dissipation equation of AFD with open boundaries is deduced and evaluated. Blade simulated testing specimens are designed. The vibration measurements are performed by RC-3000 vibration exciter and detected by applying the contactless laser vibrometer system. The theoretical results consist with the experimental results, and both show that AFD appears promising performance in vibration suppression. We also present how the structure parameters, such as installation position, air film length and thickness, and thin skin thickness, influence the vibration suppression effect.

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