Vibration frequency measurement using a local multithreshold technique

Vibration frequency measurement using a local multithreshold technique.

In this paper, we demonstrate the use of a video camera for measuring the frequency of small-amplitude vibration movements. The method is based on image acquisition and multilevel thresholding and it only requires a video camera with high enough acquisition rate, not being necessary the use of targets or auxiliary laser beams. Our proposal is accurate and robust. We demonstrate the technique wi...

Measurement and Analysis of Low Frequency Vibration

Low frequency vibration occurs especially in ground transportation, either as a cause in adjacent environment or within the vehicle itself. The piezoelectric accelerometers commonly used for vibration measurement are not suitable, hence other sensors capable of measuring accelerations down to sub-hertz region have to be used. Based on some previous experience with MEMS acceleration sensors a th...

A new low-frequency vibration technique for blind-side inspections

The application of low-frequency acoustic methods for nondestructive testing has a very long history, probably originating with a simple tap technique. These techniques have been successfully applied to a variety of materials and are widely used for the assessment of the quality of bonded sheet metals. They have also proved useful in the NDE of composite materials, particularly honeycomb panels...

A Real-Time Vibration Frequency Measurement System of Bridge Pier

This study developed a real-time remote monitoring system (RTRMS) to receive the vibration frequency of bridge pier. The system included a front station and a middle station. A multi-hop wireless routing is employed to transmit the data from the front to the middle station. The front station includes a receiver equipped to receive the vibration frequency, and a wireless sensor network to transm...

Solution of Pipeline Vibration Problems By New Field-Measurement Technique