The aim of this paper is to conduct experimental modal analysis and numerical simulation to verify the structural characteristics of a deployable-retractable wing for aircraft and spacecraft. A modal impact test was conducted in order to determine the free vibration characteristics. Natural frequencies and vibration mode shapes were obtained via measurement in LMS Test. Lab. The frequency respo...

in the present study, modelling and vibration analysis of carbon nanotubes/ fiber/ polymer composite microplates are investigated. the governing equations of the carbon nanotubes/ fiber/ polymer composite microplates are derived based on first order shear deformation plate theory, rather than other plate theories, due to accuracy and simplicity of polynomial functions. the modified couple stres...

in this paper, natural frequencies of the sandwich plates with soft flexible core and composite face sheets are obtained. three-dimensional (3d) finite element method (fem) is used for constructing and analyzing of the sandwich plates to obtain their natural frequencies. continuity conditions for transverse shear stresses at the interfaces as well as transverse flexibility and transverse normal...

In recent years, acoustic emission (AE) sensors and AE-based techniques have been developed and tested for gearbox fault diagnosis. In general, AE-based techniques require much higher sampling rates than vibration analysis-based techniques for gearbox fault diagnosis. Therefore, it is questionable whether an AE-based technique would give a better or at least the same performance as the vibratio...

The vibration problems of uniform and nonuniform Euler-Bernoulli beams have been solved analytically or approximately [1-5] for various end conditions. In order to calculate fundamental natural frequencies and related mode shapes, well known variational techniques such as Rayleigh_Ritz and Galerkin methods have been applied in the past. Besides these techniques, some discretized numerical metho...

Vibration problems in rotors can be extremely frustrating and may lead to greatly reduced reliability. By utilizing the proper data collection and analysis techniques, the faults because of vibration can be discovered and predicted. The signal analysis is important in extracting fault characteristics in fault diagnosis of machinery. The traditional signal analysis can not settle for non-station...

Holographic interferometry was used to study the vibration modes of a C4 handbell. Holographic interferograms were made of four of the vibration modes of the bell. Finite element analysis was used to create a preliminary model of the bell.

transmission of blast waves is a complex phenomenon and the characteristics vary with blast design parameters and geo-technical properties of medium. frequency of vibration and triggering component for structural excitation generally quantifies safe vibration magnitude. at closer distance or higher elevations than the blast locations, vertical or transverse component will be the first arrival t...

UNLABELLED The internationally accepted limit values and the health effects of hand-transmitted vibration exposure have been described extensively in the literature from temperate climate countries but not from a tropical climate environment. OBJECTIVES We conducted a systematic review of the health effects of hand-transmitted vibration exposure in tropical countries to determine the characte...

Mechanical-electrical analogous circuit models are widely used in electromechanical system design as they represent the function of a coupled electrical and mechanical system using an equivalent electrical system. This research uses electrical circuits to establish a discussion of simple active vibration control principles using two scenarios: an active vibration isolation system and an active ...