in this paper the active vibration control of a four-story shear frame instrumented with piezoelectric actuators is presented. the piezoelectric actuators are hosted on the columns in two manners and the produced controlling forces by actuators are considered in the equation of motion. the smart structure modeling and control design is carried out using matlab software in state space form. subs...

Linear vibration absorbers are a valuable tool used to suppress vibrations due to harmonic excitation in structural systems. Limited evaluation of the performance of nonlinear vibration absorbers for nonlinear structures exists in the current literature. The state of the art is extended in this work to vibration absorbers in their three major physical implementations: the mechanical vibration a...

Systems that exhibit flexible dynamics are susceptible to vibration caused by changes in the reference command and from external disturbances. Feedback control is an obvious choice to deal with these vibrations, but in many cases, it is insufficient or difficult to implement. Input shaping does not deal with vibration excited by external disturbances; however it has proven beneficial for reduci...

The dynamic viscoelasticity of full-size wood composite panels (WCPs) under the free-free vibrational state were determined by a vibration testing method. Vibration detection tests were performed on 194 pieces of three types of full-size WCPs (particleboard, medium density fiberboard, and plywood (PW)). The dynamic viscoelasticity from smaller specimens cut from the panels was measured using a ...

Silicon-MEMS gyroscope is an important part of MEMS ( Micro Electrical Mechanical System). There are some disturb ignored in traditional gyroscope that must be evaluated newly because of its smaller size (reach the level of micron). In these disturb, the air pressure largely influences the performance of the MEMS gyroscope. Different air pressure causes different gas damping coefficient for the...

The analysis of smart spring vibration isolation system is analyzed through MATLAB simulation. The results show suppressing dominant vibration mode of platform. In the paper controllers developed for the smart spring are linear and nonlinear. This paper deals with MIMO system analysis of low frequency dominant modes, which are critical, examined first by linear controller techniques and then wi...

This study investigated the prediction of the discomfort caused by simultaneous noise and vibration from the discomfort caused by noise and the discomfort caused by vibration when they are presented separately. A total of 24 subjects used absolute magnitude estimation to report their discomfort caused by seven levels of noise (70-88 dBA SEL), 7 magnitudes of vibration (0.146-2.318 ms(- 1.75)) a...

A hybrid control scheme for vibration reduction of flexible spacecraft during rotational maneuvers is investigated by using variable structure output feedback control (VSOFC) for attitude control and smart materials for active vibration suppression. The proposed control design process is twofold: design of the attitude controller using VSOFC theory acting on the hub and design of an independent...

In this study, nonlinear vibration of axially moving strings in thermal environment is investigated. The vibration haracteristics of the system such as natural frequencies, time domain response and stability states are studied at different temperatures. The velocity of the axial movement is assumed to be constant with minor harmonic variations. It is presumed that the system and the environment...

This paper outlines a mathematical framework necessary to determine the optimal transducer force for a given vibration input. This relationship, between input vibration parameters and transducer force gives a critical first step in determining the optimal transducer architecture for a given vibration input. This relationship also yields a theoretical maximum energy output for a system with a gi...