In this paper a method is proposed for the reduction of vibration of loads carried by planar gantry crane, with hoisting of the load. The proposed method is based on the preconditioning of the inputs to the system by digital filtering the input function. Conventional FIR or IIR filters can be used for the preconditioning approach. Simulation results were used to demonstrate the effectiveness of...

In this paper, vibration control is performed by using piezoelectric elements which are one of the smart actuator. An operator-based robust nonlinear control system by using robust right coprime factorization approach and a nonliliner property of hysteresis model is proposed. Considering the hysteresis in the piezoelectric actuator, assuming that an aircraft vertical tail is forced vibration mo...

The simulation of granular particles in a quasi-two-dimensional container under vertical vibration as an experimental accessible model for granular gases is performed. The velocity distribution function obeys an exponential-like function during the vibration and deviates from the exponential function in free-cooling states. It is confirmed that this exponentiallike distribution function is prod...

An efficient vibration estimation method for synthetic aperture radar (SAR) systems based on phase-analysis method is presented. Small vibrations, which consist of multiple frequency components and are usually rather weak, introduce phase modulation in radar echoes. They contain important signatures of objects. Extracting and analyzing the phase from radar echoes is one of the significant appro...

This paper demonstrates the potential of applying PDlike fuzzy logic controller for active vibration control of piezoelectric Stewart platforms. Through simulation, the control authority of the piezo stack actuators for effectively damping the Stewart platform vibration can be evaluated for further implementation of the system. Each leg of the piezoelectric Stewart platform consists of a linear...

This paper presents an investigation on the undesirable vibration of an oblique-stud stator frame in a large hydropower generator by means of experimental and finite element (FE) analysis. First, field experimental tests were performed, and the results indicate that the main vibration component comes from electromagnetic factors. Then, a 2D-magnetic and 3D-mechanical FE model was developed to i...

now a days, structures with planar geometry such as sheet metals, have attracted special consideration among advanced techno logia, and hence investing vibration behavior of sheet metal is of prim important . in particular regarding dynamical investigations, if the natural frequencies get ignored, the resonance phenomena can exert noun computing damages to the structure and systems. in this res...

Vibration analysis can be used as a more sensitive alternative to conventional techniques for the detection of loosening of total hip replacement (THR) components. The vibration modes of the human femur and of selected THR prosthetic stems were studied by experimental modal analysis using a CADA-X system and by finite element simulation using MARC/Mentat software. Two hypotheses were formulated...

This paper discusses the controller design of a PZTactuated suspension dual-stage servo system in hard disk drives. The proposed control structure includes an active vibration damping control loop and a trackfollowing control loop. The vibration damping control loop, which runs at a faster rate than the trackfollowing control loop, utilizes a PZT element on a PZT-actuated suspension as a vibrat...

This paper presents the design and characterization of micro-fabricated 0.5 MHz silicon-based ultrasonic nozzles. Each nozzle is made of a piezoelectric drive section and a silicon-resonator consisting of five Fourier horns, each with half wavelength design and twice amplitude magnification. Results of impedance analysis and measurement of longitudinal vibration confirmed the simulation results...