Evaluation Method of Assembly Yield in Three-Dimension Single-Station Assembly Process Based on Number-Theoretical Net and 3DCS

2013 ◽  
Vol 579-580 ◽  
pp. 270-275
Author(s):  
Ze Jun Wen ◽  
Fan Zhang ◽  
Jia Hu
Keyword(s):  
Evaluation Method ◽  
Three Dimensional ◽  
Total Sample ◽  
Three Dimension ◽  
Assembly Process ◽  
Variation Propagation ◽  
Single Station ◽  
Net Method ◽  
Component Assembly ◽  
Assembly Deviation

Evaluation method of assembly yield in three-dimension single-station assembly process is presented based on Number-Theoretical Net (NT-net) and 3DCS. Firstly, based on the analysis of fixture deviation affect assembly deviation under arbitrary layout, the three dimensional single-station assembly deviation model under arbitrary layout is developed. Then, the principle of generating good lattice point (GLP) based on NT-net method is introduced. Afterwards, taking fixture locating variations which are sampled using NT-net method for input vectors, the samples are substituted into assembly deviation model of dimension variation propagation in single-station assembly processes to get output vectors. The statistics for qualified sample is accomplished, after comparing output vectors with the variations of measuring points on component. Assembly yield in three-dimension single-station assembly processes is gained when qualified sample divided by total sample. Finally, a real case in sheet metal assembly is given as an example to calculate the assembly yield in three-dimension single-station assembly processes. The result is validated by 3DCS.

Evaluation Method and Application of Assembly Yield in Two-Dimension Multi-Station Assembly Processes Based on Number-Theoretical Net

2012 ◽  
Vol 522 ◽  
pp. 921-926
Author(s):  
Ze Jun Wen ◽  
Zheng Qiang Zhu ◽  
Yan Ming Zhao ◽  
Fan Zhang
Keyword(s):  
Evaluation Method ◽  
State Space Model ◽  
Total Sample ◽  
Two Dimension ◽  
Automotive Body ◽  
Variation Propagation ◽  
Net Method ◽  
Good Lattice ◽  
Good Lattice Point ◽  
Component Assembly

Method for calculating assembly yield in two-dimension multi-station assembly processes is developed based on Number-Theoretical Net (NT-net). The discrepancy of NT-net is analyzed, and the principle of generating good lattice point (glp) based on NT-net method is introducted. Afterwards, taking fixture locating variations which are sampled using NT-net method for input vectors, the samples are substituted into state space model of dimension variation propagation in multi-station assembly processes to get output vectors. The statistics for qualified sample is accomplished, after comparing output vectors with the variations of measuring points on component. Assembly yield in two-dimension multi-station assembly processes is gained when qualified sample divided by total sample. Finally, a real case in automotive body floor assembly is given as an example to calculate the assembly yield in two-dimension three-station assembly processes. The result is validated by using Monte carlo simulation. It provides a new way to predict assembly yield in two-dimension multi-station assembly processes.

scholarly journals In-Process Measurement of Three-Dimensional Deformations Based on Speckle Photography

2021 ◽  
Vol 11 (11) ◽  
pp. 4981
Author(s):  
Andreas Tausendfreund ◽  
Dirk Stöbener ◽  
Andreas Fischer
Keyword(s):  
Evaluation Method ◽  
Process Analysis ◽  
Plane Deformation ◽  
Three Dimensional ◽  
Machining Process ◽  
Image Correlation ◽  
Speckle Photography ◽  
Process Measurement ◽  
Out Of Plane ◽  
Plane Deformations

In the concept of the process signature, the relationship between a material load and the modification remaining in the workpiece is used to better understand and optimize manufacturing processes. The basic prerequisite for this is to be able to measure the loads occurring during the machining process in the form of mechanical deformations. Speckle photography is suitable for this in-process measurement task and is already used in a variety of ways for in-plane deformation measurements. The shortcoming of this fast and robust measurement technique based on image correlation techniques is that out-of-plane deformations in the direction of the measurement system cannot be detected and increases the measurement error of in-plane deformations. In this paper, we investigate a method that infers local out-of-plane motions of the workpiece surface from the decorrelation of speckle patterns and is thus able to reconstruct three-dimensional deformation fields. The implementation of the evaluation method enables a fast reconstruction of 3D deformation fields, so that the in-process capability remains given. First measurements in a deep rolling process show that dynamic deformations underneath the die can be captured and demonstrate the suitability of the speckle method for manufacturing process analysis.

Three Dimensional Detection of the via in the PCB CT Image Using Morphology Operation

2015 ◽  
Vol 752-753 ◽  
pp. 1406-1412
Author(s):  
Lei Zeng ◽  
Jian Chen ◽  
Han Ning Li ◽  
Bin Yan ◽  
Yi Fu Xu ◽  
...  
Keyword(s):  
Nondestructive Testing ◽  
Printed Circuit Board ◽  
Three Dimensional ◽  
Detection Algorithm ◽  
Circuit Board ◽  
Dimensional Structure ◽  
Three Dimension ◽  
Shape Information ◽  
Printed Circuit ◽  
Testing Technology

In modern industry, the nondestructive testing of printed circuit board (PCB) can prevent effectively the system failure and is becoming more and more important. As a vital part of the PCB, the via connects the devices, the components and the wires and plays a very important role for the connection of the circuits. With the development of testing technology, the nondestructive testing of the via extends from two dimension to three dimension in recent years. This paper proposes a three dimensional detection algorithm using morphology method to test the via. The proposed algorithm takes full advantage of the three dimensional structure and shape information of the via. We have used the proposed method to detect via from PCB images with different size and quality, and found the detection performances to be very encouraging.

Modeling of Thermoplastic Materials for the Process-Simulation of Press-Fit Interconnections on Moulded Interconnected Devices

2012 ◽  
Vol 134 (3) ◽  
Author(s):  
Thomas Fellner ◽  
Elena Zukowski ◽  
Jürgen Wilde ◽  
H. Kück ◽  
H. Richter ◽  
...  
Keyword(s):  
Finite Element ◽  
Three Dimensional ◽  
Base Material ◽  
Creep Model ◽  
Assembly Process ◽  
Temperature Dependent ◽  
Reliability Modeling ◽  
Finite Element Software ◽  
Press Fit ◽  
Temperature Loads

This investigation is aimed at the modeling of both the fabrication process and the reliability of press-fit interconnections on moulded interconnect devices (MID). These are multifunctional three-dimensional substrates, produced by thermoplastic injection moulding for large-series applications. The assembly process and subsequently the durability of press-fit interconnections has been modeled and proved with a finite element software. Especially, a simulation tool for process optimizations was created and applied. In order to obtain realistic results, a creep model for the investigated base material, a liquid-crystal polymer (LCP), was generated and verified by experiments. Required friction coefficients between metal pin and base material were determined by adapting simulations and experiments. Retention forces of pins pressed into substrate holes during as well after the assembly process, and after temperature loads were predicted by simulations. Additionally, the decreasing extraction forces over time due to creep in the thermoplastic base material have been predicted for different storage temperatures as well with finite element analyses. Following, the numerical results of the process and reliability modeling were verified by experiments. It is concluded that the behavior of the mechanical contact of the pin-substrate system, can be suitably described time- and temperature-dependent.

The Research of Virtual Assembly of Cotton Picker Roller Based on Virtual Reality

2010 ◽  
Vol 156-157 ◽  
pp. 496-499
Author(s):  
Wen Lei Sun ◽  
Yu Shan Cao ◽  
Wei Sun
Keyword(s):  
Virtual Reality ◽  
Three Dimensional ◽  
Virtual Assembly ◽  
Assembly Process ◽  
Software Environment ◽  
Virtual Scene ◽  
Mapping Software ◽  
Three Dimensional Mapping ◽  
Cotton Picker ◽  
Dimensional Mapping

This paper took the roller of a new cotton picker as the example, drew its various parts and assemblyed overally in the three-dimensional mapping software environment of UG, imported the models into the virtual reality assembly platform by the interface between UG and VAPlatform, added the virtual hand and carried through the virtual assembly in the virtual scene based on the certain assembly restriction in UG. The paper realized the visualization of the assembly path, offered the foundation for the feasible assembly path, and finally obtained the reasonable assembly process, provided a set of reasonable operation guide for the workers to assemble the cotton pickers.

Variation Analysis for Compliant Assembly

2000 ◽  
Author(s):  
S. Jack Hu ◽  
Yufeng Long ◽  
Jaime Camelio
Keyword(s):  
Sheet Metal ◽  
Assembly Line ◽  
Assembly Process ◽  
Variation Analysis ◽  
Assembly Lines ◽  
Compliant Assembly ◽  
Single Station ◽  
Dimensional Variation ◽  
Sheet Metal Assembly

Abstract Assembly processes for compliant non-rigid parts are widely used in manufacturing automobiles, furniture, and electronic appliances. One of the major issues in the sheet metal assembly process is to control the dimensional variation of assemblies throughout the assembly line. This paper provides an overview of the recent development in variation analysis for compliant assembly. First, the unique characteristics of compliant assemblies are discussed. Then, various approaches to variation modeling for compliant assemblies are presented for single station and multi-station assembly lines. Finally, examples are given to demonstrate the applications of compliant assembly variation models.

Three Dimensional Bacteria Concentration by Negative Dielectrophoresis

2013 ◽  
Vol 699 ◽  
pp. 251-256
Author(s):  
T. Hisajima ◽  
L. Mao ◽  
K. Shinzato ◽  
M. Nakano ◽  
J. Suehiro
Keyword(s):  
Escherichia Coli ◽  
Numerical Simulation ◽  
Dielectric Layer ◽  
Parallel Plate ◽  
Three Dimensional ◽  
Three Dimension ◽  
Escherichia Coli Cells ◽  
Opposite Electrode ◽  
Novel Method ◽  
Thin Dielectric Layer

Thispaper reports a novel method to concentrate bacteria in three-dimension by negative dielectrophoretic (n-DEP) force in a microchannel. This was achieved by placing a thin dielectric layer on one of a pair of parallel plate electrodes. The dielectric layer having a home-plate like pentagonal shape, forms a gradient of electric field causing n-DEP. A three-dimensional numerical simulation of bacteria trajectory predicts that bacteria flowing a microchannel were three-dimensionally concentrated beneath the tip of the pentagonal dielectric thin layer. The trajectory and concentration of bacteria under n-DEP force were also experimentally confirmed using Escherichia coli cells. Bacteria moved along edges of the dielectric layer and were pushed to the opposite electrode, resulting in their concentration in three-dimension. The proposed device might be applicable to selective concentration of bacteria depending on their dielectric properties.

Ascertaining the “Halalness” of restaurants – scale development and validation

2019 ◽  
Vol 10 (2) ◽  
pp. 426-439 ◽  
Author(s):  
Ghazala Khan ◽  
Faiza Khan
Keyword(s):  
Scale Development ◽  
Discriminant Validity ◽  
Three Dimensional ◽  
Reliability And Validity ◽  
Total Sample ◽  
Measurement Scale ◽  
Content Type ◽  
Three Dimensional Measurement ◽  
Average Variance ◽  
Development Literature

PurposeThe purpose of this study is to develop and validate a measurement scale for determining the “Halalness” of restaurants and related behaviour among Muslim consumers in the absence of the halal logo. The study responded to scholarly calls for further research in exploring the consumption practices of Muslims.Design/methodology/approachThe scale was developed and validated using a rigorous methodology recommended in the scale development literature. The study used a total sample of 438 (66 respondents for pilot study, 208 for exploratory survey and 164 for the confirmatory survey) to collect the data. Reliability and validity of the measurement scale was established through average variance extracted, Cronbach’s alpha, composite reliability, critical ratios and discriminant validity.FindingsThe results from the exploratory factor analysis and confirmatory analysis propose a three-dimensional measurement scale with 14 items for establishing the “Halalness” of restaurants and including social servicescape; neighbourhood and behaviour.Research limitations/implicationsThe study was unable to validate a number of cues and behaviour such as the presence of images in the restaurant or consumer responses to the presence of alcohol. The researchers are therefore encouraged to test these cues.Originality/valueThe study addresses a gap in Islamic literature, and it is among the first to provide conceptualisation and empirically validate a scale for measuring the “Halalness” of restaurants. The scale was tested and validated based on samples drawn from two different countries, thereby allowing for generalizability.

scholarly journals Joint Investigation and 3D Visual Evaluation of Rock Mass Quality

2020 ◽  
Vol 2020 ◽  
pp. 1-16
Author(s):  
Haiping Yuan ◽  
Chenghao Chen ◽  
Yixian Wang ◽  
Hanbing Bian ◽  
Yan Liu
Keyword(s):  
Rock Mass ◽  
Quality Evaluation ◽  
Evaluation Method ◽  
Three Dimensional ◽  
Rock Mass Classification ◽  
National Standard ◽  
Ratio Method ◽  
Rock Mass Quality ◽  
Close Range ◽  
Mass Classification

In order to realize the high efficiency quality classification and three-dimensional visualization of engineering rock mass and to solve the technical difficulties of the traditional rock mass quality evaluation method such as high labor intensity, long process time consumption, many intervention processes such as scale measurement and manual calculation, and nonintuitive classification results, this paper puts forward a 3D visual rock mass quality evaluation method and system based on close-range photography, which optimizes the traditional rock mass quality evaluation method, makes the rock mass classification three-dimensional and visible, and realizes the estimation of unrevealed rock mass quality evaluation index. The research results show the following: (1) The method of storing joint information by close-range photography and extracting joint information by human-computer interaction improves the working efficiency and the process is safe and controllable compared with the traditional method of collecting fracture parameters. (2) Based on the statistical analysis of 97 groups of roadway survey data, the comprehensive statistical regression formula between BQ value of Chinese national standard and RMR value is given, and there is a good correlation between BQ value and RMR value of rock mass quality index. (3) Based on the power-inverse ratio method, the three-dimensional model of rock mass classification of the mine was established, and the cutting model obtained the current distribution diagram of rock mass quality grade, providing scientific reference for drilling, blasting, support, and other production design optimizations.

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