The aim of this study was to analyze electromyography (EMG) responses of vastus lateralis muscle to different whole-body vibration frequencies. For this purpose, 16 professional women volleyball players (age, 23.9 +/- 3.6 years; height, 182.5 +/- 11.1 cm; weight, 78.4 +/- 5.6 kg) voluntarily participated in the study. Vibration treatment was administered while standing on a vibrating platform w...

in this paper deflection and free vibration of sandwich panel is studied. the core of sandwich panels is made of hexagonal honeycomb and faces are made of two different materials of carbon fiber reinforced plastic and k-aryl/epoxy covering. the governing equations are deduced from the first order sheer deformation theory (fsdt) and they are solved using generalized differential quadrature metho...

This paper is devoted to the computation of statistical characteristics of the response of discrete vibration systems with a random external excitation. The excitation can act at multiple points and is modeled by a time-shifted random process and its derivatives up to the second order. Statistical characteristics of the response are given by expansions as to the correlation length of a weakly c...

35th ANNIVERSARY ISSUE Sinusoidal vibration testing has evolved over the years for many good reasons. Initially, from a military standpoint, a predominant part of vibration excitation was from propeller driven aircraft. Here, system resonances could easily be excited during runup, or in the more unfortunate circumstance, during sustained operation at flight speed. Although there initially was o...

This study investigated the biodynamic response (BR) distributed at the palm of the hand subjected to a random vibration. Twelve male subjects were used in the experiment. Each subject applied three coupling actions (grip-only, push-only, and combined grip and push) on a simulated tool handle at three different levels (50, 75, and 100 N) of palm force. This study found that the hand-arm system ...

Thepresent paper discusses active vibration control of a cantilever beam subjected to random base excitation. The smart materials used are piezoelectric patches for both as sensor and actuator, and actuation based on the surface strains. Finite element model of the smart beam is obtained using Euler-Bernoulli formulation. Positive Position Feedback (PPF) controller is proposed for active dampin...

The vibration fatigue durability of eutectic Sn37Pb and near-eutectic Pb-free Sn3.9Ag0.6Cu solders is quantified, based on test data available from the literature [1]. The tests use random broad-band excitation (between 20Hz & 2000Hz), on selected SAC and SnPb surface mount interconnect styles. In the test, step-stress excitation was applied in the out-of-plane direction by increasing the RMS e...

This paper presents an adaptive control scheme for simultaneous precision positioning and vibration suppression of intelligent structures. First, the structure and materials system of an active composite panel with piezoelectric ceramic patches are introduced. An adaptive control scheme, which consists of an adaptive feedback and two adaptive feedforward controllers, is then proposed. The two a...