The vibration velocities of the seat platform and traditional mechanical reduction vibration device were measured through tests, which provided certain basis for proposing and design of the parallel mechanism with six degree of freedom in subsequent paragraphs. Adopting the parallel mechanism as the main part of the seat and the active joints with spring damping elements as the reduction vibrat...

A fuzzy logic based digital sinusoidal acceleration waveform amplitude controller for a PC based electrodynamic vibration actuator is presented. The fuzzy logic control (FLC) purpose is to reproduce pre-defined sinusoidal acceleration amplitude at the vibration table of a vibration actuator system. Sinusoid vibration profiles (sine and linear sine sweep) are considered for a closed-loop control...

Vibration is a manual technique used widely to assist with the removal of pulmonary secretions. Little is known about how vibration is applied or its effect on the respiratory system. The purpose of this study was to describe mechanical consequences of vibration on the chest wall of a normal subject and the effects of vibration on expiratory flow rates and volumes. The effects of vibration were...

Body lean response to bilateral vibrations of soleus muscles were investigated in order to understand the influence of proprioceptive input from lower leg in human stance control. Proprioceptive stimulation was applied to 17 healthy subjects by two vibrators placed on the soleus muscles. Frequency and amplitude of vibration were 60 Hz and 1 mm, respectively. Vibration was applied after a 30 s o...

We are developing a new method using ultrasonic longitudinal and torsional vibration of a hollow-type stepped horn for hole machining. We foresee that the equipment can be simplified and miniaturized. In this paper, ultrasonic vibration sources of a hollow-type stepped horn without a diagonal slits vibration converter and with a diagonal slits vibration converter are used. The longitudinal and ...

Since many rotor systems normally operate above their critical speeds, the problem of accelerating the machine through its critical speeds without excessive vibration draws increasing attention. This paper provides an analytical imbalance response of the Jeffcott rotor under constant acceleration. The response consists of three parts: transient vibration due to the initial condition of the roto...

Vibration fixtures, at times, have resonant frequencies that exist in the frequency range needed for conducting vibration tests. These resonant frequencies can cause significant problems when running vibration tests over ranges which include these resonances. A test engineer will attempt to control the shaker system through a feedback accelerometer which controls the level of vibration input in...

Condition Monitoring of rotating equipment has been a very important aspect in the field of maintenance engineering. There are various types of condition monitoring techniques, namely: Vibration Analysis, Oil Debris Analysis, Ferrography, Temperature analysis. Among all these techniques, vibration analysis have gained much importance in the field of condition monitoring because of its accuracy ...

building caused by floor impact sound. In this study, the concrete slab measured vibration impact sound for evaluation floor vibration of deteriorated buildings that fails to satisfy with the minimum thickness. In this experimental study, the vibration scale by impact sound was calibrated and compared with ISO and AIJ standard for vibration. The results show that vibration in slab with thicknes...

Background and purpose: Vibration caused by ventilation systems in buildings is one of the harmful physical factors that can cause harm to residents. Therefore, measuring and controlling vibration is important. Materials and Methods:  In the first step of the study, the vibration accelerometer was placed on the base of a fan where the vibrations were sent toward the duct wall. A vibration asse...