This paper reviews shearography and its applications for testing of composite structures. Shearography is a laser-based technique for fullfield measurement of surface deformation. Unlike holography, it does not require special vibration isolation; hence it can be employed in field/factory environments. The technique has already received considerable industrial acceptance for nondestructive test...

We have performed laser-Doppler vibrometry measurements of the vibration of a double-paddle oscillator. Seven modes with principally out-of-plane motion have been identified. Their resonance frequencies and mode shapes are in excellent agreement with three-dimensional finite element simulations. We have found that the second antisymmetric torsional mode has exceptionally good vibration isolatio...

In this paper, structural nonlinear vibration control using base isolation system is studied. A nonlinear structure model with base isolation devices is developed to analyze the control effect of base isolated structure. A bi-linear hysteresis model is incorporated into the structure to mimic nonlinear behaviors. Simulation is made on this nonlinear structure with base isolation system. It can ...

A combined hydraulic engine mount and buffer is proposed in this study for use in the mid-priced vehicle. In some vehicle design projects, an engine is selected to use in a new car design. To achieve the desired vibration conditions, the mount can be redesigned with exorbitant costs and long-term research. The idea of using a buffer in the combination of the conventional engine mount is to sugg...

A dynamic profiler is presented that is capable of precision measurement of surface roughness in the presence of significant vibration or motion. Utilizing a special CCD camera incorporating a micro-polarizer array and a proprietary LED source, quantitative measurements were obtained with exposure times of <100 μsec. The polarization-based interferometer utilizes an adjustable input polarizatio...

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...