This paper puts forward a robust change detection procedure able to analyze the transient seismic motion and the vibration structure response, as well as to determine the changes in the amplitude and frequency content of the structure. This technique makes use of an impulse invariant transformation that will enable us to obtain an equivalent model of the vibration structure, represented by a pa...

A new ultra-low power (ULP) wireless sensor network (WSN) is proposed to monitor the vibration properties of critical structures such as buildings, bridges, and the wings and bodies of aircrafts. The new scheme integrates energy harvesting, data sensing, and wireless communication into a unified process, and it is fundamentally different from all the existing WSNs. In the new WSN, self-powered ...

In this paper, an active control structure used piezoelectric stack actuator is built to suppress vibration due to internal incentive in gear transmission. Because the gear system is timevariant and unknown, an offline modeling technique is unable to tracking the changes in the secondary path, an adaptive filter algorithm used online secondary path modeling method is proposed to the active vibr...

When compared with a traditional planetary gearbox, the split torque gearbox (STG) potentially offers lower weight, increased reliability, and improved efficiency. These benefits have driven the helicopter manufacturing community to develop products using the STG. However, this may pose a challenge for the current gear analysis methods used in Health and Usage Monitoring Systems (HUMS). Gear an...

Rotor crack detection method by using multi-vibration signals gathered at the basements is presented in this paper. The finite element software ANSYS is applied for analyzing the vibration response characteristics of the basement to determine sensor configuration. Feature fusion for time-domain statistics of multiple sensors is performed by using the support vector machine to diagnose the depth...

Nanometer vibration analysis of a target has been demonstrated by a self-aligned optical feedback vibrometry technique that uses a laser-diode-pumped microchip solid-state laser. The laser output waveform, which was modulated through interference between a lasing field and an extremely weak (<- 100-dB) frequency-modulated (FM) feedback field, was analyzed by the Hilbert transformation to yield ...

The current research talks about a designed accelerometer system which is able to measure every type of mechanical vibration. The applied vibration in this survey is called seismic wave. Then the measured wave by this novel system is transf ormed to a specif ic function using spline interpolation. This explicit function can be used as a reference signal in the technique PWM to be made in curren...

We proposed heterodyne angle deviation interferometry (HADI) for angle deviation measurements. The phase shift of an angular sensor (which can be a metal film or a surface plasmon resonance (SPR) prism) is proportional to the deviation angle of the test beam. The method has been demonstrated in bubble and speaker’s vibration measurements in this paper. In the speaker’s vibration measurement, th...

A deep-sea resonant sandwich linear ultrasonic motor is proposed and designed. We determine the parameter of its structure by finite-element analysis. The piezoelectric actuator adopts compound vibration mode of fifth order bending vibration and second order longitudinal. The mode degeneracy of that is completed. We manufacture the prototype to measure the performance of it. We measure its vibr...

An adaptive truss structure with self-learning active vibration control system is developed. A fuzzy-neural network (FNN) controller with adaptive membership functions is presented. The experimental setup of a two-bay truss structure with active members is constructed, and the FNN controller is applied to vibration suppression of the truss. The controller first senses the output of the accelero...