M. A. Hussein

Computer-aided design and simulation of strip layout for progressive die planning using Petri nets

Planning of strip layout is one of the important activities of progressive die design in sheet metal industries. The optimum and economical die design mainly depends on the design of strip layout. Many methodologies are used to determine optimum strip layout, but there is no literature available for strip-layout simulation. Petri net is one of the most suitable methodologies for simulation of strip layout. In this article, two research contributions are described (1) to apply the visual Petri net to simulate the sequential workstations in the strip layout of part and (2) to integrate the parametric design of strip layout and simulation using Petri-net technique. To demonstrate the present research contribution, two case studies are also discussed.

Selection, Modeling and Prediction of Life of Stripper of Compound Die

Compound dies are widely used for production of pierced blanks with high accuracy. Stripper is one of the major components of a compound die. In this paper, research work involved in the selection, modeling and prediction of life of stripper of compound die is presented. Knowledge based system (KBS) approach is used for selection of size of stripper. The knowledge base is constructed through coding of production rules of IF-THEN variety in AutoLISP language. Further, a CAD system is developed for automatic modeling of stripper of compound die. This CAD system works in conjunction with the KBS developed for selection of stripper. An artificial neural network (ANN) model is developed for prediction of life of stripper. Various factors affecting life of stripper are investigated through FEM analysis and the critical simulation values are determined. The proposed ANN model is trained by using FEM simulation results. The proposed work is tested successfully on different sheet metal parts taken from stamping industries. A sample run is also demonstrated in this paper.

Computer-aided process planning in prismatic shape die components based on Standard for the Exchange of Product model data

Insufficient technologies made good integration between the die components in design, process planning, and manufacturing impossible in the past few years. Nowadays, the advanced technologies based on Standard for the Exchange of Product model data are making it possible. This article discusses the three main steps for achieving the complete process planning for prismatic parts of the die components. These three steps are data extraction, feature recognition, and process planning. The proposed computer-aided process planning system works as part of an integrated system to cover the process planning of any prismatic part die component. The system is built using Visual Basic with EWDraw system for visualizing the Standard for the Exchange of Product model data file. The system works successfully and can cover any type of sheet metal die components. The case study discussed in this article is taken from a large design of progressive die.

An automatic system for deciding bend sequence of bending parts

Abstract To decide a proper bend sequence for manufacturing a defect-free bending part on a bending die is tedious, time-consuming and highly experience-based activity. This article presents the research work involved in the development of an automated system for determining bend sequence of a bending part. The proposed system is structured in form of five modules developed, respectively, for part feature extraction, identification of base plane, categorisation of bends, grouping of bends in various categories and prioritisation of bend groups. The system finally gives its output in form of proper bend sequence for manufacturing bending part. System modules are coded in Visual Basic 6.0 and integrated with CAD software. The CAD software is used for pre- and post-processing of bend sequencing. The system has been tested successfully on various bending parts taken from sheet metal industries.

Feature Extraction and Manufacturability Assessment of Sheet Metal Parts

To automate the process of die design, firstly all design features of sheet metal parts are to be extracted automatically from drawing files by a computer-aided system. After feature extraction, next important activity is manufacturability assessment of sheet metal parts. Traditional process of manufacturability assessment of sheet metal parts involves calculations and decisions, which have to be made on the basis of experience and practice codes without the computer aids. In the present chapter, an automatic feature recognition system is described. The system initially extracts the basic entities from the 3-D CAD model and recognizes various design features of flat parts, bending parts, and deep drawn parts. The system is coded in AutoLISP language. The system displays the details of all design features of part in the prompt area of AutoCAD software. The system has been installed on Autodesk AutoCAD software. The present chapter also describes a knowledge-based system (KBS) for manufacturability assessment of sheet metal parts. Knowledge obtained from published literature, die designers, and process planners has been analyzed, tabulated, and incorporated into a set of production rules of the IF–THEN variety. The system is coded in the AutoLISP language and user interface is developed using visual basic (VB). The system output includes recommendations on the suitability of design features of the part for required manufacturing operations. The knowledge base of this system can be modified depending upon the capabilities of a specific shop floor. The low cost of the system makes it affordable for process planners working in small-and medium-size sheet metal industries.

CAD system for automatic modelling of compound dies

Abstract Modelling of compound die is an important activity usually carried out by highly experienced die designers in sheet metal industries. These days, various CAD systems are being used for die modelling. But these systems are for general purpose and can provide limited assistance in drafting of die components. This study describes the research work involved in the development of a CAD system for automatic modelling of compound dies for use in sheet metal industries. The proposed system is organised in nine modules. The system modules execute in conjunction with expert system developed for design of compound die. Modules are coded in AutoLISP language, and user interface is created using Visual Basic and AutoCAD software. The proposed system is capable to generate drawings (2-dimensional and 3-dimensional) of all major die components and die assembly automatically in the drawing editor of AutoCAD software. The system has been tested successfully on a wide variety of sheet metal parts taken from industries. As this system can be implemented on a PC having AutoCAD software, its low cost of implementation makes it affordable even for small-scale sheet metal industries.

Knowledge-Based System for Automatic Design of Bending Dies

This chapter describes a knowledge-based system (KBS) for automatic design of bending dies. The system is developed using the production rule based approach of artificial intelligence (AI). The overall system is organized in 3 subsystems and 19 modules. System modules are coded in visual basic 6.0 language. The system is integrated with inventor CAD software. The proposed system automates all activities of design of bending die and finally gives outputs in form of drawings of die components and die assembly. It eliminates the dependency on domain experts for die design. The system is easy to operate and its knowledge base can be modified and/or updated on the advancement in technology in future.

Prediction of Life of Compound Die Using Artificial Neural Network

The present describes the research work involved in prediction of life of compound die using Artificial Neural Network (ANN). The parameters affecting the life of compound die are investigated through Finite Element Analysis (FEA) and the critical simulation values are determined. Based on FEA results, S–N approach is used for calculation of number of cycles of compound die. The number of cycles gives the number of sheet metal parts that can be produced on compound die before its failure. The proposed ANN model is tested successfully on different compound dies designed for manufacturing various industrial sheet metal parts.

An Expert System for Automatic Design of Compound Dies

The present chapter describes an expert system for automatic design of compound dies. The knowledge base of this system is constructed through coding of more than 1500 production rules of ‘IF-THEN’ variety in AutoLISP language. The system is structured in 22 modules. User interface is created using Visual Basic (VB) and AutoCAD software. The proposed system automates all major activities of design of compound die. The system finally generates the drawings (2-D and 3-D) of die components and die assembly of compound die automatically in the drawing editor of AutoCAD software. These drawings can be directly used for die manufacturing. The system can be implemented on a PC having VB and AutoCAD software and therefore its low cost of implementation makes it affordable for small scale enterprises.

Knowledge-Based System for Design of Blanking Dies

In sheet metal industries, blanking dies are considered as basic types of stamping dies. Die design is a highly experience-based task. There is no computer-aided system available for automation of design of blanking dies. This chapter describes a knowledge-based system for design of sheet metal blanking dies. The developed system can be used to analyze different die design techniques and complete the design task base on an optimum design configuration. A knowledge base for the selection of a most suitable design from 14 different designs has been constructed. The developed system uses parametric design approach for design and finally engineering drawings in 2-dimensions (2-D) and 3-dimensions (3-D) can be generated automatically. The system is tested through sample runs. The system was built on the AutoCAD platform with Visual Basic, AutoLISP programming languages and MS-Access for the database.