scholarly journals Machine Vision for As-Built Modeling of Complex Draped Composite Structures

Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 682
Author(s):  
Oliver Döbrich ◽  
Ayoh Anderegg ◽  
Nicolas Gort ◽  
Christian Brauner
Keyword(s):  
Fiber Orientation ◽  
Composite Structures ◽  
Quality Management System ◽  
Fiber Composite ◽  
Fiber Composites ◽  
Fe Model ◽  
Image Analysis System ◽  
Active Monitoring ◽  
Reinforcement Fiber ◽  
Analysis System

The transition in the use of fiber composite structures from special applications to application in the mass market is accompanied by high demands in quality assurance. The consequential costs of unclear process design, unknown fiber orientations, and uncertainty regarding the effects of any fiber angle deviations can lead to market considerations (higher costs/time for development) in mass production that advise against the use of fiber composites, despite their superiority compared with conservative materials. Active monitoring of the deposited reinforcement layers and an evaluation of the real fiber orientation can form the basis of a robust industrial use of fiber composites by a first-time right production that is able to reduce the process variability. This paper describes the application of an image analysis system to provide both geometric topology and local reinforcement fiber orientation feedback to a finite-element (FE) model. The application during an industrial composite part production is described, and the possibilities of using it for the improvement of the lightweight character, the reduction of rejects, and the realization of a quality management system are shown. The determined component data are made directly available for use in numerical simulations and, thus, they serve as a non-destructive evaluation of the components under real conditions in which all production-dependent influences that affect the fiber orientation are incorporated.

Large deformation mechanical modeling with bilinear stiffness for Macro-Fiber Composite bimorph based on extending mixing rules

2020 ◽  
pp. 1045389X2095125
Author(s):  
Kai-ming Hu ◽  
Hua Li
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Large Deformation ◽  
Composite Structures ◽  
Fiber Composite ◽  
Three Dimensional ◽  
Element Model ◽  
Fiber Composites ◽  
Mixing Rules ◽  
Macro Fiber Composite

Macro-Fiber Composite bimorph is a kind of piezoelectric actuator that allow large bending deformation. However, macro-fiber composites exhibit strong stiffness nonlinearity in their operation range, so it is difficult to accurately estimate their large deformation behavior based on a linear constitutive model. In addition, the macro-fiber composites have active and inactive parts, that significantly differ in their material sizes and properties, so it is not reasonable to consider them as uniform material. Thus, it is necessary develop an accurate modeling and analysis method for the large deformation macro-fiber composite structures. First, the mixing rules are extended to derive the three-dimensional homogenized mechanical and electrical parameters of the macro-fiber composite active part; based on these parameters, the actuation results of linear finite element model is in good agreement with the official data. Then a finite element model of the axially compressed macro-fiber composite bimorph is established, the bilinear tensile stiffness of macro-fiber composite is realized by secondary development in ANSYS. Comparison with the experimental results reveals high accuracy of the established finite element model. Thus, the developed method can be effectively used for the performance evaluation and design of the macro-fiber composite devices with large deformation.

Tensile Strength of Banana – Bamboo – Glass Fiber Reinforced Natural Fiber Composites

2014 ◽  
Vol 592-594 ◽  
pp. 1195-1199
Author(s):  
Ashwin Sailesh ◽  
C. Shanjeevi ◽  
J.Jeswin Arputhabalan
Keyword(s):  
Tensile Strength ◽  
Glass Fiber ◽  
Fiber Orientation ◽  
Natural Fiber ◽  
Fiber Composite ◽  
Natural Fibers ◽  
Fiber Composites ◽  
Natural Fiber Composites ◽  
Fiber Reinforced ◽  
Glass Fiber Reinforced

The developments in the field of composite materials are growing tremendously day by day. One such development is the use of natural fibers as reinforcement in the composite material. This is attributed to the fact that natural fibers are environmental friendly, economical, easily available and non-abrasive. Mixing of natural fiber with Glass Fibers is finding increased applications. In this present investigation Banana – Bamboo – Glass fiber reinforced natural fiber composites is fabricated by Hand – Layup technique with varying fiber orientation such as [0°G, 90°BM, 0°BN, 0°G], [0°G, 0°BM, +45°BN, 0°G] and [0°G, 0°BM, 90°BN, 0°G] and are tested for its tensile strength. The tensile strength of the fabricated composites is evaluated. The results indicated that the natural fiber composite with the fiber orientation of [0°G, 0°BM, 90°BN, 0°G] can withstand more load when compared to the samples with other fiber orientation. Nomenclature Used: BN – Banana fiber BM – Bamboo fiber G – Glass fiber

Active Monitoring for On-Line Damage Detection in Composite Structures

2003 ◽  
Vol 125 (2) ◽  
pp. 178-186 ◽  
Author(s):  
Shenfang Yuan ◽  
Wang Lei ◽  
Lihua Shi
Keyword(s):  
Damage Detection ◽  
Composite Structures ◽  
Impact Damage ◽  
Fiber Composite ◽  
Carbon Fiber Composite ◽  
Active Monitoring ◽  
Monitoring Method ◽  
Active Monitoring System ◽  
On Line ◽  
Extent Of Damage

This study focuses on an active monitoring method for damage detection applied to composite structures. Honeycomb sandwich and carbon fiber composite structures are studied. Two kinds of damage are considered: delamination and impact damage. Wavelet analysis methods are adopted to postprocess the raw monitored signal. A new damage signature is introduced to determine the presence and extent of damage in composites, while eliminating the influence of different distances between the active actuator and active monitoring elements. The proposed method is shown to be effective, reliable, and straightforward for the specimens considered in the present study, which are composed of different materials and suffer various levels of damage. An online real-time active monitoring system for damage detection is described that is based on this research.

Digital Processing of STEM Images

1981 ◽  
Vol 39 ◽  
pp. 236-237
Author(s):  
A. V. Crewe ◽  
M. Ohtsuki
Keyword(s):  
High Resolution ◽  
Low Dose ◽  
Assembly Language ◽  
Processing System ◽  
Principal Component ◽  
Digital Processing ◽  
Image Analysis System ◽  
Black And White ◽  
Analysis System ◽  
Dose Imaging

We have assembled an image processing system for use with our high resolution STEM for the particular purpose of working with low dose images of biological specimens. The system is quite flexible, however, and can be used for a wide variety of images.The original images are stored on magnetic tape at the microscope using the digitized signals from the detectors. For low dose imaging, these are “first scan” exposures using an automatic montage system. One Nova minicomputer and one tape drive are dedicated to this task.The principal component of the image analysis system is a Lexidata 3400 frame store memory. This memory is arranged in a 640 x 512 x 16 bit configuration. Images are displayed simultaneously on two high resolution monitors, one color and one black and white. Interaction with the memory is obtained using a Nova 4 (32K) computer and a trackball and switch unit provided by Lexidata.The language used is BASIC and uses a variety of assembly language Calls, some provided by Lexidata, but the majority written by students (D. Kopf and N. Townes).

Chemical Classification and Particle Sizing of Foundry Sands

1985 ◽  
Vol 43 ◽  
pp. 388-389
Author(s):  
D.S. DeMiglio
Keyword(s):  
Image Analysis ◽  
Energy Dispersive Spectrometer ◽  
Image Analysis System ◽  
Representative Sampling ◽  
Foundry Sands ◽  
Large Atomic Number ◽  
Backscattered Electron ◽  
Sand Particles ◽  
Analysis System ◽  
Reclamation System

Much progress has been made in recent years towards the development of closed-loop foundry sand reclamation systems. However, virtually all work to date has determined the effectiveness of these systems to remove surface clay and metal oxide scales by a qualitative inspection of a representative sampling of sand particles. In this investigation, particles from a series of foundry sands were sized and chemically classified by a Lemont image analysis system (which was interfaced with an SEM and an X-ray energy dispersive spectrometer) in order to statistically document the effectiveness of a reclamation system developed by The Pangborn Company - a subsidiary of SOHIO.The following samples were submitted: unreclaimed sand; calcined sand; calcined & mechanically scrubbed sand and unused sand. Prior to analysis, each sample was sprinkled onto a carbon mount and coated with an evaporated film of carbon. A backscattered electron photomicrograph of a field of scale-covered particles is shown in Figure 1. Due to a large atomic number difference between sand particles and the carbon mount, the backscattered electron signal was used for image analysis since it had a uniform contrast over the shape of each particle.

Цифровая морфометрия разнокачественности семян овощных культур

2018 ◽  
Author(s):  
F.B. Musaev ◽  
N.S. Priyatkin ◽  
M.V. Arkhipov ◽  
P.A. Shchukina ◽  
A.F. Bukharov ◽  
...  
Keyword(s):  
Seed Quality ◽  
Image Analysis System ◽  
Flatbed Scanner ◽  
The Future ◽  
Scanned Images ◽  
Computer Morphometry ◽  
Analysis System ◽  
Matrix Heterogeneity ◽  
Relationship Of ◽  
Selection Of

Приведено описание разработанной авторами методики цифровой компьютерной морфометрии семян овощных культур на основе системы анализа изображений, состоящей из планшетного сканера и программного обеспечения для автоматических измерений. В основу метода положено представление о разнокачественности семян, обусловленной генетической неоднородностью самих семенных растений, используемых в промышленном семеноводстве. Физические свойства семян (их форма и линейные размеры) – основные параметры при определении их качества. Цифровые изображения семян получены при помощи планшетного сканера HP Sсanjet 200 на базе Агрофизического НИИ с использованием серийного программного обеспечения «Argus-BIO», производства ООО «АргусСофт» (г. Санкт-Петербург). Метод состоит из подбора контрастной подложки (фона) для сканирования семян с минимальными теневыми эффектами, калибровку программного обеспечения для привязки к истинным размерным величинам, подбор параметров измерений и автоматическое распознавание цифровых сканированных изображений семян. Представлены экспериментальные данные по морфометрии экологически разнокачественных семян фасоли овощной, матрикально разнокачественных семян укропа, пастернака и лука Кристофа. Семена укропа и пастернака, собранные из разных порядков ветвления семенного растения, значительно различались по величине линейных параметров. Наиболее показательный линейный параметр семян – площадь проекции. Предложенная авторами методика цифровой морфометрии, уже использована на практике и в перспективе может быть задействована в исследованиях экологической и матрикальной разнокачественности семян овощных культур. Так, она прошла апробацию на разнокачественных семенах пяти сортов фасоли овощной (Настена, Магура, Миробела, Морена, Бажена) полученных в пяти контрастных эколого-географических условиях среды (Москва, Белгород, Ставрополь, Омск, Горки) в 2011–2012 годах. В дальнейшем методика может быть использована для улучшения качества цифровых изображений семян, изучения разнокачественности семян в том числе и для совершенствования контроля за селекционным процессом. Кроме того, она применима для изучения взаимосвязи совокупности морфометрических характеристик семян и их посевных качеств.The description of the method of digital computer morphometry of vegetable seeds developed by the authors on the basis of the image analysis system consisting of a flatbed scanner and software for automatic measurements is given. The method is based on the idea of seed quality, due to the genetic heterogeneity of the seed plants used in industrial seed production. Physical properties of seeds (their shape and linear dimensions) are the main parameters in determining their quality. Digital image of the seed obtained using the flatbed scanner, HP Sсanjet 200 on the basis of the Agrophysical research Institute with serial software “Argus-BIO”, produced by LLC “Argussoft” (Saint-Petersburg). The method consists of selection of a contrast substrate (background) for scanning seeds with minimal shadow effects, calibration of software for binding to true size values, selection of measurement parameters and automatic recognition of digital scanned images of seeds. Experimental data on the morphometry of ecologically different-quality seeds of vegetable beans, matrix seeds of dill, Pasternak and Christoph onion are presented. Seeds of dill and parsnip, collected from different orders of branching of the seed plant, significantly differed in size of linear parameters. The most revealing linear parameter seed – area projection. The method of digital morphometry proposed by the authors has already been used in practice and in the future can be used in studies of ecological and matrix heterogeneity of vegetable seeds. So, it was tested on different quality seeds of five varieties of vegetable beans (Nastena, Magura, Mirobelа, Morena, Bazhenf) obtained in five contrasting environmental and geographical conditions (Moscow, Belgorod, Stavropol, Omsk, Gorki) in 2011-2012. In the future, the technique can be used to improve the quality of digital images of seeds, study of seed diversity, including to improve the control of the breeding process. In addition, it is applicable to study the relationship of the set of morphometric characteristics of seeds and their sowing qualities.

Sign in / Sign up

Export Citation Format

Share Document