Electromagnetic transducers have been used extensively for active feedback control of mechanical vibration. In this paper, we demonstrate a new technique where an electrical impedance, connected to the terminals of an electromagnetic actuator, is designed to reduce vibration in the host structure. By measuring the coil terminal voltage and controlling the resultant current or vice-versa the cou...

Extracting an electrical energy from various environmental sources, called energy harvesting (or energy scavenging), has been attracting researchers’ attention in energy replenishable networks. In particular, a piezoelectric device based energy harvesting from ambient vibrations is a promising technique for easy of battery energy replenishment in vibration-motivated wireless sensor networks (WS...

This paper has been investigated a technique that predicts the performance of a bar-type unimorph piezoelectric vibration actuator depending on the frequency. This paper has been proposed an equivalent circuit that can be easily analyzed for the bar-type unimorph piezoelectric vibration actuator. In the dynamic analysis, rigidity and resonance frequency, which are important mechanical elements,...

Hydraulic brakes in automobiles play a vital role for the safety on the road; therefore vital components in the brake system should be monitored through condition monitoring techniques. Condition monitoring of brake components can be carried out by using the vibration characteristics. The vibration signals for the different fault conditions of the brake were acquired from the fabricated hydraul...

Bicoherence or Bispectrum analysis is emerging as a new powerful technique in signal processing, especially in areas where traditional linear spectral analysis provides insufficient information. It is most effective in analyzing systems with non-linear coupling between frequencies. Faults in rotating machineries leave their signature on the vibration signal sensors and generally manifest themse...

Application of flexible structures has been significantly, increased in industry and aerospace missions due to their contributions and unique advantages over the rigid counterparts. In this paper, vibration analysis of a flexible structure i.e., automobile wiper blade is investigated and controlled. The wiper generates unwanted noise and vibration during the wiping the rain and other particles ...

This paper introduces a new bearing fault detection and diagnosis scheme based on hidden Markov modeling (HMM) of vibration signals. First features are extracted from amplitude demodulated vibration signals obtained from both normal and faulty bearings. The features are based on the reflection coefficients of the polynomial transfer function of the autoregressive model of the vibration signal. ...

In this paper, a new tool for crack detection in operating rotors based on wavelet theory is described. Customarily, two approximate methods of spectral analysis, i.e. ShortTime Fourier transform and Wigner distribution, have been used to analyse the vibration components of cracked rotors during run-up or run-down periods. However, for both methods, high resolution cannot be achieved simultaneo...

In this paper, vibration data analysis techniques are investigated for fault diagnosis of helicopter planetary gears. A data pre-processing technique is introduced that achieves the same result as the commonly used Time Synchronous Averaging with much lower computational complexity since interpolation is not required. A notion of using raw vibration data instead of the Time Synchronous Averaged...

The dynamic response of an elastic strip foundation lying on elastic soil with saturated substrata is greatly affected by pore pressure induced by a rocking moment. In this paper, we explore the mixed boundary-value problem of the rocking vibration of an elastic strip foundation on elastic soil with saturated substrata via Biot dynamic equations. First, the wave equations concerning both the si...