Measuring the three-dimensional (3D) deformation of submerged objects through different media with stereo digital image correlation (stereo-DIC) method involves refractive optical imaging problem where non-linear transmission light is induced by a change medium density. The invalidates underlying single viewpoint assumption perspective model in regular stereo-DIC, thereby resulting erroneous measurements 3D shape and deformation. In this work, we propose stereo-DIC that overcomes considering...

This paper investigates the fracture surfaces and performance of recycled aggregate concrete (RAC) using fringe projection technology. non-contact, point-by-point, full-field scanning technique allows precise measurement RAC’s surface characteristics. research focuses on effects replacement rate, water-to-binder (w/b) ratio, maximum size properties. A decrease in w/b ratio significantly reduces roughness (Rs) fractal dimension (D), due to increased cement mortar bond strength at lower...

A simple but effective fringe projection profilometry is proposed to measure 3D shape by using one snapshot color sinusoidal pattern. One pattern encoded with a (as red component) and uniform intensity blue projected digital video projector, the deformed recorded CCD camera. The captured separated into its RGB components division operation applied channels reduce variable reflection intensity. Shape information of tested object decoded applying an arcsine algorithm on normalized subpixel...

Two methods are proposed to calibrate the revolution axis of a 360 deg, multiview fringe projection system for surface measurement. The first method is based on minimizing distance between calculated and measured points; second difference thus obtained vectors. Both able retrieve turntable, which then used transform patches at different viewing angles common coordinate. In point-based method, nonlinear minimization problem has be solved by Levenberg-Marquardt algorithm; in vector-based...

The evaluation of concrete surface roughness is crucial in the field civil engineering. purpose this study to propose a no-contact and efficient method for measurement fracture surfaces based on fringe-projection technology. A simple phase-correction using one additional strip image presented phase unwrapping improve efficiency accuracy. experimental results indicate that measuring error plane height less than 0.1mm, relative accuracy cylindrical object about 0.1%, meeting requirements...

Three-dimensional shapes of objects were evaluated with modified phase-shift lateral shearing interferometry illumination and radial basis function. A simple optical system was developed to create the fringe pattern based on Murty interferometer. The phase shift generated only by moving a plane-parallel plate along an in-plane parallel direction. novel function method presented improve quality patterns. And proper calculation window size given numerical simulation. two kinds determined...

Based on the porous structure of classic simple-cubic hollow sphere (SHS) materials, two novel configurations—simple-cubic perforated (SPHS) and ellipsoidal (SHES) structures were designed by introducing perforations in walls altering ellipsoid ratio, defined as ratio major minor axes an ellipsoid. Using 316L stainless steel raw material, a series specimens fabricated employing additive manufacturing technology. Corresponding finite element models established using Abaqus. Then experimental...

The performance of composite structures can be dramatically improved through the synergy between different constituent materials. However, topology optimization multi-material poses a heavy computational burden, which becomes more significant when load uncertainty is considered. This article proposes an efficient method to address problem robust structures. Employing property that material-field series-expansion significantly reduce number design variables, proposed improves efficiency...

A panoramic dual-directional shearography system is proposed to simultaneously determine out-of-plane deformation derivatives in two directions and globally inspect the object be tested. dichroic filter (DF), a 3CCD camera, dual-wavelength light are used configuration. The coupled with corresponding imaging sensors of camera provides independent color signals shearograms. Through adjustment tilted stereo-angle DF, which offers second wavelength-dependent measurement, an additional...

To support the execution of computation-intensive, delay-sensitive computing task by moving down and processing capability in mobile edge becomes current trend. However, when serving a large number users, how to effectively use nodes with limited resources ensure Quality service (QoS) end-user has become key issue. solve this problem, cloud remote are combined build layered architecture. Based on architecture, goal minimizing device energy consumption time, problem which is proved be convex...

This Letter demonstrates a novel lateral shear interferometer system for simultaneous measurement of three-dimensional (3D) shape and thickness transparent objects. Multi-frequency fringe patterns can be created by tilting mirrors at different inclination angles. With single camera, the multi-frequency fringes are recorded in one image. The phase-shift generated synchronously only moving plane-parallel plate along an in-plane parallel direction. According to feature materials, 3D...

Hollow sphere structures with perforations (PHSSs) in three different arrangements (simple cubic (SC), body-centred (BCC), and face-centred (FCC)) were fabricated through three-dimensional (3D) printing, the mechanical behaviours of these PHSSs under quasi-static compression investigated experimentally numerically. The results indicated that uniaxial compression, mainly undergo stages, i.e., a linear elastic stage, large deformation or plateau densification stage. During stage deformation,...

The time-averaged electronic speckle pattern interferometry (ESPI) is employed to measure the frequencies and mode shapes of thin, cantilevered plates with root-slit. first 12 order linear resonance frequency shape an intact plate determined by using FEM calculation. dynamic response specimen forced a PZT actuator measured its super-harmonic investigated experimentally. results show that principal vibration similar natural modal. In contrast forcing vibration, threshold force for much higher...

Calibration is to transform the 2D phase information world coordinates in a fringe projection 3D measurement system. For phase-to-height conversion, an equi-phase coordinate method based on two-reference-plane proposed this paper. The surface height calculated by linear interpolation using where have identical value of object and two reference planes. conventional method, called equi-coordinate paper, builds function absolute obtained subtracting from that plane same coordinate. can handle...

The in-plane electronic speckle pattern interferometry (ESPI), implemented in a Michelson stellar interferometer-like configuration, offers high sensitivity and dynamic measurement. However, its limited angle of view (AOV) remains major challenge for the rotation determination multiple objects. In this Letter, we analyze main factors that influence AOV ESPI propose an “image transmitting” approach to enlarge AOV. With aid folded dual-telescope imaging system, develop AOV-unlimited...