An approach to automating modular fixture design and assembly

In the development of a modular fixture design system, it is essential to have a modular fixture element database that can be integrated with a CAD system, in addition to the other considerations such as fixture configuration, interference checking, etc., which are also important to fixture designers. This paper describes a new method to create the fixture element database and model the fixturing towers (i.e. subassemblies). By using this method, the database can be effectively created and is easy for use in fixture assembly. The modular fixture tower database is used to represent the subassembly of fixtures. This will simplify the fixture design and assembly process. A built-in interference checking methodology is embedded in the planning stage that will ensure a collision-free fixture design. The system is developed using the knowledge- based system, ICAD, and interfacing with UG-II for modelling the workpiece. Examples of fixture design generated by the system are also provided to illustrate the development.

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FIX-DES: A Computer-Aided Modular Fixture Configuration Design System

Volume 5: 17th Computers in Engineering Conference ◽

10.1115/detc97/cie-4281 ◽

1997 ◽

Author(s):

W. Ma ◽

Z. Lei ◽

Y. Rong

Keyword(s):

Interactive Design ◽

Design System ◽

Configuration Design ◽

Fixture Design ◽

Design Modification ◽

Modular Fixture ◽

Cad Systems ◽

Fixture Element ◽

Computer Aided ◽

Fixture Configuration

Abstract This paper presents a computer-aided modular fixture design system: FIX-DES. When fixturing requirements are specified as locating/clamping surfaces and points, a fixture configuration will be automatically generated by (1) selecting fixture elements from a fixture element database to form fixture units based on fixture element assembly relationships and (2) placing the fixture units and elements into position on a baseplate while the fixturing requirements and assembly relationships (e.g., hole alignment) are maintained. The fixture element assembly relationships can be automatically established when the geometric models and fixturing functions of the fixture elements are specified so that the FIX-DES system can be easily applied to different fixture systems. The system also provides the interactive design and design modification functions for human expert involvement. The system was developed with core programs in C/C++ and interface programs in a specific CAD environment. The system has been successfully applied in industry and can be easily transferred to other CAD systems. The overall structure of the FIX-DES system is introduced in the paper. The development of the automated fixture configuration design (AFCD) functions are presented in detail. Finally a fixture configura-tion design example is given to illustrate the application of the system.

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Process and Tolerance Considerations in the Automated Design of Fixtures

Journal of Mechanical Design ◽

10.1115/1.2919404 ◽

1994 ◽

Vol 116 (2) ◽

pp. 480-486 ◽

Cited By ~ 13

Author(s):

D. A. King ◽

A. de Sam Lazaro

Keyword(s):

Data Structures ◽

Lead Time ◽

Design System ◽

Fixture Design ◽

Complex Data ◽

Cad System ◽

Knowledge Based ◽

Modern Manufacturing ◽

Interactive Session ◽

Knowledge Based Design

The long lead time for jig and fixture design is a serious bottleneck in modern manufacturing. Efforts to automate the design process using intelligent CAD systems have not been taken beyond the prototype stage mainly because of several impediments. These include the requirement of complex data structures to represent the workpiece and its attributes. Two deficiencies in existing systems for fixture design are addressed. These are (a) design for a sequence of operations and (b) design with tolerance considerations. Tolerance and process specifications are obtained from the user during an interactive session. A knowledge-based design system, REFIX, then designs a fixture for the workpiece. The fixture is optimized for a particular datum specification and sequence of operations. It is then analyzed and presented via the CAD system. REFIX is automated to minimize user-induced errors.

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Automatic Modular Fixture Generation in Computer-Aided Process Planning Systems

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1243/095440605x31968 ◽

2005 ◽

Vol 219 (10) ◽

pp. 1147-1152 ◽

Cited By ~ 8

Author(s):

B Surendra Babu ◽

P Madar Valli ◽

A V V Anil Kumar ◽

D N Rao

Keyword(s):

Design System ◽

Fixture Design ◽

Modular Fixture ◽

Computer Aided Process Planning ◽

Software Application ◽

Prismatic Parts ◽

Manufacturing Constraint ◽

Computer Aided ◽

Design Characteristics ◽

Fixture Configuration

Fixturing is the most commonly used manufacturing constraint in setup planning. The computer-aided fixture design technique is being rapidly developed to reduce the lead-time involved in manufacturing planning. An automated fixture configuration design system has been developed to select modular fixture components automatically and place them in position with satisfactory assembly relationships. In this paper, an automated fixture generation system for prismatic components is presented. Sequential steps for automatic fixture layout planning for machining setups, focusing on determining the most suitable locating and clamping positions in accordance with the 3-2-1 configuration, considering geometrical and dimensional constraints are presented. A software has been developed which takes two-dimensional-manufacturing drawings of the prismatic components as input and generates fixture design automatically. The modularity concept is incorporated in the developed software application and enables locating positions to be as wide apart as possible. The clamping positions are obtained directly opposite to the respective locators as far as possible. The software is tested successfully with numerous examples of prismatic parts involving similar design characteristics.

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A CAD-based approach to the design of fixtures for prismatic parts

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1243/0954405971516473 ◽

1997 ◽

Vol 211 (7) ◽

pp. 523-538 ◽

Cited By ~ 6

Author(s):

Y C Jeng ◽

K F Gill

Keyword(s):

Computer Aided Design ◽

Design System ◽

Fixture Design ◽

Modular Fixture ◽

Cad System ◽

Prismatic Parts ◽

Design Structure ◽

Modular Fixtures ◽

Computer Aided ◽

Inference Techniques

The design scheme presented utilizes the knowledge representation and inference techniques from artificial intelligence and the geometric modelling technique for modular fixture design on a CAD (computer aided design) system. The fixture design problem is formulated in a hierarchical design structure. A systematic approach for selecting the locating and clamping positions on an automatically generated fixture configuration is outlined for the building of modular fixtures. Modular fixture elements are selected by considering the required function and geometric limitation. The generated fixture layout is then represented in the CAD system. To demonstrate the proposed approach, a prototype AutoCAFD (automatic computer aided fixture design) system is introduced and a practical example is presented.

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DEVELOPMENT OF A KNOWLEDGE-BASED INTELLIGENT CAD SYSTEM FOR AUTOMOTIVE PANEL DIE

Journal of Advanced Manufacturing Systems ◽

10.1142/s0219686708001012 ◽

2008 ◽

Vol 07 (01) ◽

pp. 51-54 ◽

Cited By ~ 3

Author(s):

HUI-XIA LIU ◽

WEI WEI ◽

XIAO WANG ◽

LAN CAI

Keyword(s):

Die Design ◽

Design System ◽

Working Process ◽

Cad System ◽

Knowledge Based ◽

Working Principle ◽

Panel Die ◽

Automotive Panels ◽

Automotive Panel

A knowledge-based intelligent die design system for automotive panels is developed by UG software platform. This system can accomplish design intelligently and automatically through engineering rules in the knowledge base. The framework and implementation of the system are discussed. Finally, a case study of the panel die design of car trunk in the system is implemented, which illustrates working process, working principle, implement method and practicability of the system, and validates the advanced design conception proposed in this paper.

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Design and Implementation of an Intelligent CAD System

13th Design Automation Conference: Volume 1 — Design Methods, Computer Graphics, and Expert Systems ◽

10.1115/detc1987-0044 ◽

1987 ◽

Author(s):

M. J. Jakiela ◽

P. Y. Papalambros

Keyword(s):

Computer Aided Design ◽

Design System ◽

Knowledge Based Systems ◽

Production Rules ◽

Automated Assembly ◽

Cad System ◽

Design And Implementation ◽

Knowledge Based ◽

System Requirements ◽

Aided Design

Abstract System requirements and system design for integrating a production rule program and a computer aided design system are presented. An implementation using a commercially available graphics modeling system is described. A “suggestive mode” interface is programmed as an example with application to design for automated assembly. Initial use of the implementation indicates that encoding production rules is more difficult than with conventional text-only knowledge-based systems, but that this system is a more effective way to use artificial intelligence techniques in design.

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A Feature Extraction Interface for CAD Part Models

ASME 1991 Computers in Engineering Conference: Volume 1 — Artificial Intelligence; Expert Systems; CAD/CAM/CAE; Computational Fluid/Thermal Engineering ◽

10.1115/cie1991-0046 ◽

1991 ◽

Author(s):

David R. Nitschke ◽

Yuh-Min Chen ◽

R. Allen Miller

Keyword(s):

Design System ◽

Relative Positioning ◽

Neutral Form ◽

Cad System ◽

Knowledge Based ◽

Functional Specification ◽

Design And Manufacturing ◽

Feature Based ◽

The Individual ◽

Knowledge Based Design

Abstract The concept of “Features” has been recognized as a neutral form of communication between design and manufacturing. Since virtually all CAD systems define part models using B-Rep or CSG formats, a facility is needed to convert geometry based part models to ones which are feature based. This paper outlines the framework of a facility which would enable part models from any type of CAD system to be converted to a format which could be analyzed using a knowledge based design system. This facility relies on the user to recognize and isolate the individual features of the model and then extracts the dimensions, locations and relative positioning of the features within the model. These features are then organized into a feature graph for the construction of a feature based part representation. The procedures for the construction of this part representation include feature instantiation, feature placement and functional specification.

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Design System Mfk—An Important Step towards an Engineering Workbench

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1243/pime_proc_1993_207_069_02 ◽

1993 ◽

Vol 207 (2) ◽

pp. 105-116 ◽

Cited By ~ 4

Author(s):

H Meerkamm

Keyword(s):

Computer Aided Design ◽

Tolerance Analysis ◽

Design System ◽

Product Model ◽

Cad System ◽

Knowledge Based ◽

Different Types ◽

Analysis Design ◽

Aided Design ◽

Production Tolerance

The Design System mfk will support the designer by an object-orientated synthesis of parts and an integrated knowledge-based analysis. An own-product model which is completely independent from the data structure of the used computer aided design (CAD) system contains all necessary information on geometry, technology, function and organization. It allows different types of analysis: design for production, tolerance analysis, cost and stress calculation, repeated component search, etc. Usable for products of higher complexity the Design System can be seen as an approach to an engineering workbench.

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A Golf Head CAD/KBE Optimization Design System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.338.304 ◽

2011 ◽

Vol 338 ◽

pp. 304-310

Author(s):

Yung Yuan Hsu

Keyword(s):

Optimization Design ◽

Secondary Development ◽

Free Form ◽

Design System ◽

Solid Model ◽

Development Environment ◽

Cad System ◽

Knowledge Based ◽

Complex Design ◽

Free Form Surfaces

The purpose of this study was to construct a knowledge-based CAD/KBE system for the optimal design of golf heads. The inability of conventional CAD systems to identify existing knowledge during design and manufacturing processes is a current development bottleneck. Therefore, this study attempted to effectively introduce and integrate KBE technology into a CAD system, so as to achieve the objective of knowledge driven automation (KDA). This study selected golf iron heads with a complex-design surface as the research subject, adopted commercial CAD software (UG/NX) and its secondary development environment as a platform and applied perturbation vectors in the control of NURBS free-form surfaces. We changed the CAD’s entity shapes and physical properties, integrated the optimal principle of design with a CAD solid model, to automatically drive the CAD solid model of golf iron heads according to the design objectives, and constructed a knowledge-based optimal CAD design technology.

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