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Article
Publication date: 1 January 1992

Nanua Singh and Dengzhou Qi

As most existing computeraided design systems do not provide partfeature information which is essential for process planning, automaticpart feature recognition systems…

Abstract

As most existing computeraided design systems do not provide part feature information which is essential for process planning, automatic part feature recognition systems serve as an important link between Computer Aided Design (CAD) and Computer Aided Process Planning (CAPP). Attempts to provide a structural framework for understanding various issues related to part feature recognition. Reviews previous work in the field of part feature recognition and classifies known feature recognition systems for the sake of updating information and future research. Briefly introduces about 12 systems. Studies 31 systems and lists them in the Appendix based on 60 references. Comments on future research directions.

Details

Integrated Manufacturing Systems, vol. 3 no. 1
Type: Research Article
ISSN: 0957-6061

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Article
Publication date: 1 April 1989

G.J. Colquhoun, J.D. Gamble and R.W. Baines

International competition is driving manufacturing executives toplace an ever‐growing importance on the formulation of computerintegrated manufacturing (CIM) strategies as…

Abstract

International competition is driving manufacturing executives to place an ever‐growing importance on the formulation of computer integrated manufacturing (CIM) strategies as part of their corporate plans. Structured analysis and design techniques, in particular IDEF (Integrated Computer Aided Manufacturing definition method), are becoming a vital tool in the analysis and implementation of such CIM strategies. This article positively demonstrates the technique and its ability to model the link between design and manufacture in a CIM environment. The approach relates interdependencies of planning for manufacture, design and process planning within a CIM strategy. In particular it establishes the position of computer aided process planning (CAPP) in CIM architecture and evaluates a CAPP package as a potential element of a CIM strategy. The application to which IDEFo, in particular, has been used clearly demonstrates its usefulness to manufacturers as a powerful aid to the development of detailed CIM strategies.

Details

International Journal of Operations & Production Management, vol. 9 no. 4
Type: Research Article
ISSN: 0144-3577

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Article
Publication date: 1 May 2006

Slavenka Petrak and Dubravko Rogale

To develop a new method for computer‐based 3D construction of garment basic cut on a computer generated body model.

Abstract

Purpose

To develop a new method for computer‐based 3D construction of garment basic cut on a computer generated body model.

Design/methodology/approach

The method has been developed on an example of a 3D garment basic cut construction on a virtual body model, determining the position of characteristic 3D points necessary for computer‐based definition of 3D cutting pattern contour segments. Contour segments modelling, as well as the modelling of 3D cut surfaces has been done using the NURBS objects.

Findings

A 3D garment cut has been constructed, such that matches physical characteristics of the body in question and offers the necessary comfort of the cut. The surface of the 3D cut has been divided into individual 3D cutting patterns.

Research limitations/implications

The method has been developed on an example of a 3D garment basic cut construction of a single paper of clothing. However, the same principles can be applied and developed for any garment basic cut.

Practical implications

The 3D garment cut constructed can be further transformed into a network of polygons. Introducing fabric physical‐chemical properties fabric drape can be simulated, aiming at more realistic visualisation and further assessment of the garment fit. The 3D cutting patterns developed can be, applying computer‐based application of the mathematical models, transformed into 2D cutting patterns.

Originality/value

As compared to the methods developed by some previous investigations, the newly developed method offers the construction of garment 3D cut on a computer‐generated body model, granting the necessary comfort of the cut, which also means garment fitted to individual body characteristics. The 3D cut constructed can also be used as a starting point to define 2D cutting patterns in the following step, which will be matched to the physical characteristics of the model body, in the same way as the initial 3D cut.

Details

International Journal of Clothing Science and Technology, vol. 18 no. 3
Type: Research Article
ISSN: 0955-6222

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Article
Publication date: 7 July 2020

Jialu Liang, Honglian Cong, Zhe Gao, Aijun Zhang and Zhijia Dong

The weft-knitted two-side jacquard fabric has the characteristics of complicated design principle and hard technical design. The purpose of this paper is to realize the…

Abstract

Purpose

The weft-knitted two-side jacquard fabric has the characteristics of complicated design principle and hard technical design. The purpose of this paper is to realize the computer-aided design of weft-knitted two-side jacquard fabric, and provide a certain reference for the development of this type of fabric.

Design/methodology/approach

The weft-knitted two-side jacquard fabric is divided into weft-knitted two-side similar pattern jacquard fabric and weft-knitted two-side independent pattern jacquard fabric. In order to achieve the purpose of this study, firstly, the structural characteristic of weft-knitted two-side jacquard fabric is analyzed. Then, the design principle of weft-knitted two-side jacquard fabric is studied. Next, the technical model of weft-knitted two-side jacquard fabric is established. Finally, the CAD flow chart of weft-knitted two-side jacquard fabric is proposed to realize the rapid product development.

Findings

Based on the above method, through the development example of weft two-side similar pattern jacquard fabric and weft two-side independent pattern jacquard fabric, the computer-aided design of the weft two-side jacquard fabric is verified.

Research limitations/implications

Because of limited research studies, three-dimensional computer-aided design of weft-knitted two-side jacquard fabric loop structure will be studied in the further research, and the technical design speed needs to be improved to meet the needs of large patterns and positioning patterns.

Practical implications

The computer-aided design of weft-knitted two-side jacquard fabric will offer a certain reference for product development, technical principles, performance research and computer simulation for the in-depth study of the fabric.

Social implications

The computer-aided design of weft-knitted two-side jacquard fabric will simplify the fabric design process and improve the efficiency of new fabric development, and provide the industries a time-saving and cost-saving approach for new fabrics development.

Originality/value

The author analyzes the structural characteristic of the fabric by the physical fabric, summarizes design principle of the fabric through production process, uses mathematical methods to establish a three-dimensional technical model of the fabric, and proposes the CAD flow chart of weft-knitted two-side jacquard fabric, which has good theoretical significance and practice of weft-knitted two-side jacquard fabric.

Details

International Journal of Clothing Science and Technology, vol. 33 no. 1
Type: Research Article
ISSN: 0955-6222

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Article
Publication date: 16 April 2020

Krishnaja Maturi and Susovon Samanta

The purpose of this paper is to derive the small-signal/canonical model derivation of the high-side active clamp forward converter (ACFC) with diode rectification for…

Abstract

Purpose

The purpose of this paper is to derive the small-signal/canonical model derivation of the high-side active clamp forward converter (ACFC) with diode rectification for ideal and with resistive parasitics. It also covers the analysis of ACFC small-signal model with resistive parasitics using computer-aided modeling software Personal Computer Simulation Program with Integrated Circuit Emphasis (PSPICE) 16.6. The effects of variation of system parameters on the ACFC’s state transfer functions and operations have been highlighted in this paper.

Design/methodology/approach

The large-signal model and small-signal model of the ACFC with diode rectification has been derived using AC small-signal modeling approach.

Findings

The operating point of the converter changes with the consideration of resistive parasitics compared with the ideal case. The response obtained from the hardware matches with the time domain response of the averaged model and switch model developed in PSPICE.

Research limitations/implications

This paper limits the study of ACFC small-signal behavior by using computer-aided design software PSPICE. The dead time of the converter is not considered because it is negligible when compared with the on and off time. The leakage inductance which plays a role in zero voltage switching of the ACFC switches is neglected in the analysis as it is very small compared to the magnetizing inductance. The switching losses are not considered in the modeling.

Practical implications

The mathematical computation of deriving the system transfer functions from canonical model is complex and time consuming.

Originality/value

The modeling with resistive parasitics improves the effectiveness of the equivalent model. Also, the analysis with computer-aided modeling software PSPICE gives reliable results in less time.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 39 no. 2
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 1 January 1986

G. Southern

A software package is described that attempts to develop students' knowledge of Computer Aided Production Management (CAPM) systems and an awareness of the power of the…

Abstract

A software package is described that attempts to develop students' knowledge of Computer Aided Production Management (CAPM) systems and an awareness of the power of the computer to predict the future by iteratively simulating individual workshop operations. It demonstrates the techniques of CAPM by means of manual simulation. Students then operate and adjust a simple computer simulation model and compare it with the manual exercise. Both versions are described and compared. The CAPM system is presently installed on the ACT Sirius and the IBM personal microcomputers. It consists of a series of basic programs and data files in four modules. There is wide scope for using both versions in degree courses in mechanical and production engineering and production management.

Details

International Journal of Operations & Production Management, vol. 6 no. 1
Type: Research Article
ISSN: 0144-3577

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Article
Publication date: 1 May 1994

N. Brännberg and J. Mackerle

This paper gives a review of the finite element techniques (FE)applied in the area of material processing. The latest trends in metalforming, non‐metal forming and powder…

Abstract

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming and powder metallurgy are briefly discussed. The range of applications of finite elements on the subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for the last five years, and more than 1100 references are listed.

Details

Engineering Computations, vol. 11 no. 5
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 1 April 2005

Xiaojun Wu, Weijun Liu and Michael Yu Wang

The representation of Heterogeneous Object (HO) is divided into two categories: Data model (DM) and material evaluation paradigm (MEP). A hybrid methodology with geometry…

Abstract

The representation of Heterogeneous Object (HO) is divided into two categories: Data model (DM) and material evaluation paradigm (MEP). A hybrid methodology with geometry model and volumetric dataset to represent heterogeneous properties is proposed in this paper. Geometry model of an object can guarantee the accuracy of the final HO slices; and volumetric dataset lends the flexible manipulability and other advantages to HO representation. Two MEPs, namely distance field (DF) based and Fixed Reference Features & Active Grading Source(s) (FRF&AGS) are presented to facilitate the process of HO representation according to the designer)s input parameters. The DM can be modified interactively with users until the final satisfactory result is obtained. In this paper, a scheme of HO slicing is described. In this method, we utilize the slices contour of geometrical model as constraint to reconstruct the HO slices, which can theoretically achieve the same accuracy with the geometrical shape. Some examples of Heterogeneous object represented with our scheme are provided.

Details

Multidiscipline Modeling in Materials and Structures, vol. 1 no. 4
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 1 January 1989

Hans‐Georg Lauenroth

The aim of the applied systems analysis of scientific‐technological innovation is to identify the most effective innovation fields and to develop innovation strategies…

Abstract

The aim of the applied systems analysis of scientific‐technological innovation is to identify the most effective innovation fields and to develop innovation strategies. This cannot be achieved without the development of theoretical foundations, practical methods and principles, a heuristic algorithm and a computeraided decision system. Such a system is described in this article, and represents, it is claimed, the first steps towards a computeraided decision system for innovation strategies.

Details

Kybernetes, vol. 18 no. 1
Type: Research Article
ISSN: 0368-492X

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Article
Publication date: 20 April 2010

Dušan N. Šormaz and Chandu Tennety

Recognition of machining features is an essential step in the development of efficient‐automated process plans from solid modeling data. This process represents the…

Abstract

Purpose

Recognition of machining features is an essential step in the development of efficient‐automated process plans from solid modeling data. This process represents the effective interpretation of the geometric data in a computeraided design (CAD) model to create semantically rich manufacture‐oriented features such as holes, slots, pockets, and others that may be exploited in downstream computeraided manufacturing/computeraided process planning applications. Most successful approaches towards feature recognition have been based on hint‐based procedures operating on a 3D B‐Rep model. The purpose of this paper is to propose an approach by which features are identified in a solid model that is built mainly using sweep solid modeling operations.

Design/methodology/approach

Part geometric model is queried for both 2D and 3D geometric elements. Feature hints are generated by an analysis of sweep operations and their 2D sketches, which are defined prior to building the solid model. These hints are then analyzed and validated by applying a two‐phase approach: 2D validation in the sketch geometry; and 3D validation in the final constructive solid geometry tree of the solid model. Valid hints are the basis for the creation of a machining feature model that can be input to a process planning module. In addition, interaction information for machining features is extracted from both 2D hints and their 3D validation. Feature interaction information is obtained by analysis of face/edge neighborhood and their geometric relations in both 2D and 3D spaces.

Findings

This approach provides a benefit of performing the majority of geometric analysis in 2D space which is much simpler and computationally more efficient than corresponding analyses in 3D space. Only minimal portion of the analysis is computed on 3D solid models. The approach is implemented in the Java‐based prototype system and is demonstrated and tested on several real‐world examples.

Research limitations/implications

The initial prototype implementation is limited to prismatic parts and linear sweep. Only hole and slot feature can be recognized due to the fact that pocket recognition appears to be trivial.

Practical implications

Motivation for this approach is in the fact that sweep operations from 2D sketches are very commonly used in the mechanical design process, so the approach may be applicable in practical applications of CAD.

Originality/value

This novel approach provides value to product designers and manufacturing planners since linear (extrusion) and circular (rotation) sweeps are very popular design engineer tools.

Details

Assembly Automation, vol. 30 no. 2
Type: Research Article
ISSN: 0144-5154

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