The active vibration suppression of a single flexible link manipulator using a piezoelectric actuator is investigated. For this purpose, a finite element (FE) model is developed for the modal and transient analysis of a cantilever beam and a flexible link manipulator. A proportional control strategy is employed in a FE model to adjust the voltage applied to the piezoelectric actuator so as to c...

in this work an improved method for designing a linear vibrational absorber, excited by random vibrations is presented and analyzed. first, analytical expressions, for non-stationary white noise accelerations, are derived. the criterion is different from the conventional criteria, used for structural design under random vibration, and it is based on minimum displacement or acceleration response...

OBJECTIVES The main objective was to study the acute vascular effects in the hands of normal healthy subjects of a complex vibration spectrum similar to that generated by many industrial hand held tools. The effects of repeated bouts of vibrations and alterations in the intensity of vibration were also studied. METHODS Blood flow was measured by venous occlusion plethysmography with strain ga...

The lack of adequate equipment and measurement tools in whole-body vibration has imposed significant constraints on what can be measured and what can be investigated in the field. Most current studies are limited to single direction measurements while focusing on simple postures. Besides the limitation in measurement, most of the current biomechanical measures, such as the seat-to-head transmis...

The biodynamic responses to the human body give an understanding of why human responses to vibration (changes in health, comfort, and performance) vary with the frequency and direction of vibration. Studies have shown that biodynamic responses also vary with the magnitude of vibration and that the backrests of seats influence the transmission of vibration to the seated human body. There has bee...

In the present work, the biodynamic response behavior of seated human body subject to vibration in vertical direction have been extensively examined. The biodynamic response parameter of seated human body have been analyzed in terms of apparent masss (AM).The AM describe “to –the -body”force motion relationship at the interface of huma and seat. The present work proposed the six degrees of free...

This paper presents a study on the frequency response of a capacitive micro-beam resonator under various applied stresses. The governing equation whose solution holds the answer to all our questions about the mechanical behavior is the nonlinear electrostatic equation. Due to the nonlinearity and complexity of the derived equation analytical solution are not generally available; therefore, the ...

Vibrating ankle muscles in freely standing persons elicits a spatially oriented postural response. For instance, vibrating the Achilles tendons induces a backward displacement of the body while vibrating the tibialis anterior muscle tendons induces a forward displacement. These displacements have been called vibration induced falling (VIF) responses and they presumably are automatic. Because of...

The present study has established equal sensation curves for steering wheel hand-arm rotational vibration. Psychophysical response tests of 20 participants were performed in a steering wheel rotational vibration simulator using the category-ratio Borg CR10 scale procedure for direct estimation of perceived vibration intensity. The test stimuli used were sinusoidal vibrations at 22 third octave ...

OBJECTIVE The aim of this study was to investigate the exposure-response relationship of hand-arm vibration exposure to neurological symptoms (numbness) of the hand in a cohort of vibration-exposed workers. METHODS The baseline cohort comprised 241 office and manual workers with and without exposure to hand-arm vibration. Numbness (the symptom or event) in the hand was assessed for all subjec...