Transient response analysis is widely used in mechanical systems; with a single stimulation the mechanical behavior of the system could be characterized. Commonly, the entrance used in transient systems is a delta function, due to the possibility of stimulate the system in a wide range of frequencies. Unfortunately, the Dirac function is not easy to achieve. For this work we stimulated a mechanical shaker with a step function obtaining a Gaussian-type displacement of the spike. The spike is then used as the entrance signal for a square elastic plate. The measurement of the convolved transient response of an elastic plate is obtained by means of a high speed camera working at 10,000 fps with an out of plane speckle interferometer. Experimental results are shown.
Bringing the image of a static object to the focus of a system is a relative easy task. However, when the object is being
moved, the system has to be adapting some parameters according to the object displacement. For small movements,
some detection systems are not able to distinguish the new position of the object. The Vectorial Shearing interferometer
(VSI) is able to detect small changes in the position through the measurement of the defocus associated with this
displacement. We present a method to detect and asses defocus of a wavefront by using a VSI. We present experimental
results.
Into space, stars are the most common source of light. Planets, comets and other types of rocks reflect the incoming light
from near stars. It´s said that a planet is hidden when the light from the star is brighter than the reflected light from the
planet. Vectorial Shearing Interferometer (VSI) is able to distinguish between the light coming from the planet and the
light coming from the star, obtaining information the relative position of the planet. We present a simulated method to
detect faint sources in the way of bright sources using a VSI based in the detection of the tilt of the wavefront coming
from the planet.
A joint transform correlator (JTC) is presented. In the proposed setup the joint transform of the images to be correlated
is filtered by an infinite Ronchi ruling, which is generated by a spatial light modulator, SLM, at the Fourier plane. A
lens produces the spatial integral of the product of the joint transform of the composite input and the amplitude
transmittance of the spatial light modulator, and a photodetector acquire the total light energy transmitted by the SLM.
The proposed technique significantly reduces the processing time needed for real-time applications.
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