A Guideline for the Design of Sinusoidal Excitation Equipment

A novel viscoelastic model of four-wire suspension structure with damping gel in an optical pickup actuator was identified and validated. A two-stage method was developed for the identification of inertia, damping, and spring parameters in the dynamic model. The inertia and spring parameters were identified from static tests. With the identified parameters in the dynamic model, the damping parameters were identified through sinusoidal excitation tests. The accuracy of utilizing fractional derivative to model the damping of polymer damper was validated by carrying out error analysis. The fractional transfer function with voltage input was identified and compared with the transfer function of classical model.

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Frequency Response Analysis of Damped Dual Mass Flywheel

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.724.271 ◽

2015 ◽

Vol 724 ◽

pp. 271-274 ◽

Cited By ~ 1

Author(s):

Rong Zeng ◽

Zheng Feng Jiang ◽

Xing Wan

Keyword(s):

Frequency Response ◽

Piecewise Linear ◽

Vibration Damping ◽

Torsional Stiffness ◽

Response Analysis ◽

Frequency Response Analysis ◽

Power Train ◽

Detail Design ◽

Stiffness And Damping ◽

Sinusoidal Excitation

s:Aiming at circumferential arc spring dual mass flywheel (CSDMF), this paper carries out analysis on the piecewise linear model and calculates the frequency response of damped model under sinusoidal excitation. Being combined with the calculate results, the research respectively analyzes the value of inertia ratio, torsional stiffness and damping parameters. The analysis results show that the greater the damping, inertia ratio of primary and secondary flywheels are, the torsional stiffness, the more obvious vibration damping of the dual mass flywheel would be. To meet the vibration damping requirements, the detail design of the three parameters need to be combined with power train and the torsion characteristic of CSDMF.

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A Nonlinear Calibration Method Based on Sinusoidal Excitation and DFT Transformation for High-Precision Power Analyzers

Journal of Sensors ◽

10.1155/2021/5578361 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Wenjian Zhou ◽

Sheng Yang ◽

Li Wang ◽

Hanmin Sheng ◽

Yang Deng

Keyword(s):

High Precision ◽

Interpolation Method ◽

Spline Interpolation ◽

Calibration Method ◽

Calibration Error ◽

Initial Moment ◽

Calibration Process ◽

Calibration Methods ◽

Nonlinear Calibration ◽

Sinusoidal Excitation

For most high-precision power analyzers, the measurement accuracy may be affected due to the nonlinear relationship between the input and output signal. Therefore, calibration before measurement is important to ensure accuracy. However, the traditional calibration methods usually have complicated structures, cumbersome calibration process, and difficult selection of calibration points, which is not suitable for situations with many measurement points. To solve these issues, a nonlinear calibration method based on sinusoidal excitation and DFT transformation is proposed in this paper. By obtaining the effective value data of the current sinusoidal excitation from the calibration source, the accurate calibration process can be done, and the calibration efficiency can be improved effectively. Firstly, through Fourier transform, the phase value at the initial moment of the fundamental frequency is calculated. Then, the mapping relationship between the sampling value and the theoretical calculation value is established according to the obtained theoretical discrete expression, and a cubic spline interpolation method is used to further reduce the calibration error. Simulations and experiments show that the calibration method presented in this paper achieves high calibration accuracy, and the results are compensation value after calibration with a deviation of ± 3 × 10 − 4 .

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