As the 2nd report, we present a practical calculation method for torsional vibration of highly damped system with rubber couplings. This calculation system, constructed by a modal analysis technique, outputs frequency response characteristics, forced vibration responses, and mode animations. In respect of a damping model and calculation accuracy, it was verified that the assumption of general v...

The addition of sand to cement paste was found to degrade the vibration damping ability, as shown by decreases in both loss tangent and storage modulus under flexure. However, further addition of silica fume more than restored the vibration damping ability, due to the silica fume causing increases in both loss tangent and storage modulus. Silica fume increased the loss modulus of mortar by as m...

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...

Abstract—In this paper, a theoretical investigation on the dynamic characteristics of one degree of freedom vibration system equipped with inerter of variable inertance, is presented. Differential equation of movement was solved under proper initial conditions in the case of free undamped/damped vibration, considered in the absence/presence of the inerter in the mechanical system. Influence of ...

There are over one million workers exposed to hand-arm vibration in the United States. Cases of handarm vibration syndrome have been reported in the U.S. since 1918. Typical hand-arm vibration exposure conditions are given in this presentation. Vibration control methods are discussed; these include vibration damping and isolation, use of antivibration (A/V) tool and gloves, and the application ...

A tool adaptor with built-in active vibration damping device to dynamically stabilize the turning process is presented in this paper. It can be used in standard CNC-lathes and allows the usage of off-the-shelf tool heads. The vibration compensation system is based on a multilayer piezoactuator that is in collocation with a piezoelectric force sensor. An analogue controller based on the integral...

The characterization and modeling of the dynamic behavior of many built-up structures under vibration conditions is still a subject of current research. The present study emphasizes the theoretical investigation of slip damping in layered and jointed welded cantilever structures using finite element approach. Application of finite element method in damping analysis is relatively recent, as such...

This paper is concerned with efficient integration of bilinear H∞ control and adaptive inverse control to attain vibration isolation of structure installed with a semi-active MR damper in which its damping force is controllable by input voltage. The structure with MR damper is expressed by a bilinear dynamic equation. The role of the bilinear H∞ controller is to provide the desired damping forc...

Nowadays it is commonly considered that high damping materials which have both the good mechanical properties as structural materials and the high damping capacity for vibration damping are the most direct vibration damping solution. In metals and alloys however, exhibiting simultaneously high damping capacity and good mechanical properties has been noted to be normally incompatible because the...

For application of porous and granular materials to vibro-acoustic controls, a finite dynamic strength of the solid component (frame) is an important design factor. The primary goal of this study was to investigate structural vibration damping through this frame wave propagation for various poroelastic materials. A measurement method to investigate the vibration characteristics of the frame was...