A force-feedback control system for VIV experiments is designed and evaluated for the purpose of achieving high accuracy free vibration tests. Through an organized approach, this work details specific methods for minimizing the combined effect of mass and damping using control system fundamentals. The dynamics of the closed-loop system are analyzed, a numerical model constructed and a control s...

Vibration tests are commonly used to design or qualify products such as electronics, auto parts, and consumer goods, and ensure they can withstand transportation and normal use or occasional vibration shocks. Many vibration tests specify random, sine, or classic shock vibration profiles. These produce vibrations from mathematically parameterized models and result in very predictive and consiste...

Modal parameters obtained from modal testing (such as modal vectors, natural frequencies, and damping ratios) have been used extensively in system identi"cation, "nite element model updating, and structural health monitoring. As an alternative to modal vectors, load-dependent Ritz vectors have been shown useful in various areas of structural dynamics such as model reduction and damage detection...

Assessment (staging) of workers exposed to vibration, based solely on a subjective history, has been shown to be unsatisfactory. The internationally agreed use of a sensorineural component in the Stockholm classification requires the use of sensory objective tests. Four hundred and twenty two subjects were assessed by a subjective history supplemented by multiple objective tests. These tests co...

Background and Aims: Whole body vibration exercise by affecting the neuromuscular system and mechanical mechanisms increase muscles strength. This study investigated the effect of whole body vibration training on neuromuscular function of elderly men. Methods: Based on a randomized controlled trial design, 72 retired elderly men with a mean age of 73.00 ± 2.67 years participated in thisstudy. A...

Vibration injury to the hands was first reported in 1911 in workers using compressed air tools [1]. Since then, mechanization has become more widespread, with a corresponding rise in the incidence of vibration injuries. Employers, legislators, machinery and tool manufacturers, and physicians in general have all been slow to recognize and effectively address the problem. Fortunately, some tool m...

Numerous vibration control techniques, employing both passive and active methods, have been developed and tested over the last several decades. Some of these techniques are in widespread use, while others have rarely or never left the laboratory. This paper considers the value that vibration damping and control of aircraft fins and appendage structures can have in reducing loads and subsequent ...

This randomized cross-over study was designed to investigate the effects of a 4-min vibration bout on muscle performance and body balance in young, healthy subjects. Sixteen volunteers (eight men, eight women, age 24-33 years) underwent both the 4-min vibration- and sham-interventions in a randomized order on different days. Six performance tests (stability platform, grip strength, isometric ex...

To evaluate neurological symptoms in the vibration syndrome, 55 patients with vascular and neurological symptoms in the hand who had been exposed to vibration were examined. Their exposure to vibration was estimated and neurological vascular symptoms were evaluated according to symptom scales. Temperature thresholds were measured on the right thenar eminence and on the distal volar aspect of th...

Tests that allow the precise determination of psychophysical thresholds for vibration and grating orientation provide valuable information about mechanosensory function that are relevant for clinical diagnosis as well as for basic research. Here, we describe two psychophysical tests designed to determine the vibration detection threshold (automated system) and tactile spatial acuity (handheld d...