Purely Declarative Feature-Based Design With Feature Type Property Maintenance

2004 ◽  
Author(s):  
Dhaval Lokagariwar ◽  
Bernhard Bettig
Keyword(s):  
Design Process ◽  
Research Work ◽  
Building Blocks ◽  
Feature Representation ◽  
Software Systems ◽  
Design Environment ◽  
Design Features ◽  
Planning Algorithm ◽  
Feature Based ◽  
Feature Based Design

Commercial feature-based design systems are based on describing the design model in some form of sequential representation of primitive shapes and operations called features. In these systems, the overall design process, the behavior of building blocks and the characteristics of the final model, are governed by the construction sequence. These systems do not check for the conformity of the final shape with the actual design intent of features, and allow their design and engineering intent to be altered during the design process. The research work presented here describes a new design methodology and feature representation for facilitating a design environment that is independent of any construction order or constraint-based dependencies and provides a mechanism for maintaining design and engineering intent of the design features. The methodology works by dynamically evaluating the features using a planning algorithm such that the validity of each feature is maintained. These are intended to serve as a generic template that can be used to design and develop specific design features and CAD software systems.

SINFONIA: An Open Feature-Based Design Module

1994 ◽  
Author(s):  
J. Ovtcharova ◽  
S. Haßinger ◽  
A. S. Vieira ◽  
U. Jasnoch ◽  
J. Rix
Keyword(s):  
Shape Representation ◽  
Design Feature ◽  
Modular Architecture ◽  
Design Environment ◽  
Design Features ◽  
Cad System ◽  
Feature Based ◽  
Definition Of ◽  
Feature Based Design ◽  
Solid Modeler

Abstract Sinfonia is a module for feature-based design which is configurable to users and applications within diverse CAD environments, particularly in the area of mechanical engineering. Sinfonia has an open and modular architecture that allows to modify and extend existing functionalities, and to integrate new modeling facilities and application tasks. This module enables the users to work with standard pre-defined design features delivered with the module, or to define dynamically their own specific design features during the design session. Furthermore, Sinfonia allows the interactive definition of constraints concerning the product semantics. Definition and administration of constraints in feature-based models provided by a consistency manager is supported to reach semantical correctness of the part models. The main modules of Sinfonia are the Feature Modeler and the Design Feature Manager. The Feature Modeler is responsible for the instantiation of features and the creation of the feature-based model. The Design Feature Manager allows feature data and design processes to be managed in a uniform way. The CAD system environment in which Sinfonia is integrated consists of the following modules: the User Interface System and the Application modules (offering tools for interaction of the user with application specific part models and for communication with external systems and applications, such as NC modules, etc.), the Solid Modeler (responsible for creating the shape representation of the feature-based model), the Consistency Manager (providing services to handle all kinds of different constraints within the design environment) and the Product Database which includes all services for storing and retrieving various product data.

Instantiation and Manipulation of User-Defined Freeform Features

2008 ◽  
Author(s):  
Thomas R. Langerak
Keyword(s):  
Design Process ◽  
Current Literature ◽  
Design Features ◽  
Shape Model ◽  
Target Shape ◽  
General Methodology ◽  
Feature Based ◽  
Definition Of ◽  
High Level ◽  
Feature Based Design

One of the sub-topics of CAD research is the topic of feature-based design. Features are characteristic parts of a shape to which functional or parameter information can be attached. By using features in a design process, high-level interrogation and editing of a shape model is enabled. It is widely accepted that feature-based design methods should be able to handle user-defined features. Much work has been done on the definition of features and the management of feature definitions, but very little work has been done on the instantiation of these features on a target shape, especially in the domain of freeform shape. This paper discusses the current literature on freeform feature-based design and identifies the issues that play a role in the instantiation and manipulation of freeform features on target shapes. Also, a general methodology is proposed for the instantiation and manipulation of freeform features. Finally, an implementation of the proposed methods and some application examples are given.

Representing Tolerance and Assembly Information in a Feature-Based Design Environment

1991 ◽  
Author(s):  
Rajneet Sodhi ◽  
Joshua U. Turner
Keyword(s):  
User Interface ◽  
Design Environment ◽  
Assembly Design ◽  
Assembly Features ◽  
Feature Based ◽  
The Creation ◽  
High Level ◽  
Feature Based Design

Abstract This paper describes a strategy for representing tolerance information and assembly information in a feature-based design environment. The concept of designing with features is extended to incorporate the specification of tolerance information. This allows appropriate tolerancing strategies to be provided within the feature definitions themselves. Thus a closer connection is formed between features and the functional intent implicit in their use. The concept of designing with features is also extended to incorporate the specification of assembly information, through the use of assembly features which provide a high-level user interface for the creation and modeling of assemblies, and which handle the identification and creation of mating relations between components. Several examples of component and assembly design using this extended feature-based approach are presented.

Modeling of Feature-Based Design Process

1998 ◽  
Author(s):  
Fei Gao ◽  
Dieter Roller
Keyword(s):  
Design Process ◽  
Data Exchange ◽  
Concurrent Design ◽  
Product Model ◽  
Product Data ◽  
Product Models ◽  
Critical Issues ◽  
Feature Based ◽  
Feature Based Design ◽  
Feature Evolution

Abstract Capturing design process is becoming an important topic of feature-based modeling, as well as in product data exchange, concurrent design, and cooperative design. Three critical issues on the modeling of design process are considered in this paper, namely, feature concepts, feature evolution, and the semantic consistencies of the states of product models. A semantics-based product model is introduced to facilitate the description of both conceptual and detailed models, and to maintain the semantic consistencies of product states. The process is represented by feature states and their evolution records. Feature type variation and prototype-based design are proposed to support feature evolution. A conceptual description of the design process and an example are given.

Design Reasoning Using Plastic Injection Molding Primary Features

1996 ◽  
Author(s):  
Stephen L. Wood
Keyword(s):  
Building Blocks ◽  
Basic Design ◽  
Cad Systems ◽  
Functional Aspects ◽  
Frequency Of Use ◽  
Feature Based ◽  
The Individual ◽  
Feature Based Design ◽  
Design Reasoning ◽  
Plastic Injection

Abstract The conceptual design of industrial components requires the engineer to be knowledgeable and competent in designing with features. Basic design features are the primary building blocks of designers: mechanical engineers, industrial engineers, material processing engineers, and tooling specialists. Each feature is specifically used to satisfy an intended function by the individual designer. How the features are used is based upon the experience of the designer and the potential of various features to satisfy specific functions. This paper develops the primary features used by designers in the injection plastic molding domain, according to their functional properties. The analysis of a part’s functions satisfied by various features, along with the frequency of use, gives an overview of the most pertinent aspects of feature based design. The next generation CAD systems should incorporate design reasoning as a part of the design process algorithms and the capacity to analyze the functional aspects of each feature.

FDDL: A Feature Based Design Description Language

1989 ◽  
Author(s):  
P. H. Gu ◽  
H. A. ElMaraghy ◽  
L. Hamid
Keyword(s):  
Computer Aided Design ◽  
Ease Of Use ◽  
Feature Representation ◽  
Planning System ◽  
Mechanical Assembly ◽  
Description Language ◽  
Design And Manufacturing ◽  
Feature Based ◽  
Representation Scheme ◽  
Feature Based Design

Abstract This paper presents the development of a new high-level design language called Feature based Design Description Language — FDDL. The traditional and computer-aided design and manufacturing procedures were analyzed and the important gaps between CAD and CAM have been identified. These include the lack of uniform representation of parts and products, and lack of effective links between CAD and CAM. The FDDL is proposed and designed in association with a feature representation scheme as a means of integrating design and manufacturing tasks planning. Its syntax, semantics and vocabulary have been defined taking into consideration ease of use, compatibility with engineering terminology and ease of computer implementation. The FDDL system consists of a number of lexical analyzers, a parser and three code generators. Once the products or parts modeled using FDDL or the feature based modeler are processed by the FDDL system, syntax error free input files are created for use by manufacturing task planning systems. The FDDL has been applied to a feature based cellular manufacturing planning system, an expert automated CMM inspection task planner, and a mechanical assembly sequence planner.

Methodology and Implementation of Dynamic Design Advisor (DDA) in a Feature-Based System

1999 ◽  
Author(s):  
Tridip K. Bardhan ◽  
Venkat N. Rajan ◽  
Abu S. M. Masud
Keyword(s):  
Design Stage ◽  
Design Environment ◽  
Regular Feature ◽  
Part Geometry ◽  
Advisory System ◽  
Systematic Methodology ◽  
Feature Based ◽  
Feature Based Design ◽  
Pipeline Design ◽  
First Time

Abstract Designing right the first time decreases cost significantly. If requirements of downstream activities could be considered during conceptual design, fewer changes would be required later. A design advisory system can provide enough information to the designer to achieve this goal of designing right at the conceptual stage. A systematic methodology for design advising in a feature-based design environment is developed to identify problems at the design stage, and provide the designer the opportunity to correct them. Five pre-conditions are also identified for this methodology. During the development of the part geometry, a multi-digit code is added to every feature. Based on the code, all applicable design rules are checked as constraints and in case of constraint violation, suggestions are generated and presented to the designer. During the design process, the designer can check a design rating, generated from the extent to which the constraints are satisfied. An example session is also presented to illustrate the ten steps of this method. To validate the developed methodology, a DDA system for pipeline design is developed in an actual industrial application. Effectiveness of the DDA methodology is analyzed by comparing the designers’ performance using the feature-based DDA system with performance using a regular feature based system. The performance measures used are: the number of errors in a design and the time taken to complete the design. Statistical results indicate that designers perform better with the DDA system in terms of fewer errors and less time to design.

Feature-Based Assembly Design: Concepts and Design Environment

1997 ◽  
Author(s):  
Monica Bordegoni ◽  
Umberto Cugini
Keyword(s):  
Research Work ◽  
The European Union ◽  
Design Environment ◽  
Design Concepts ◽  
Assembly Design ◽  
Part Geometry ◽  
Mechanical Assemblies ◽  
Feature Based ◽  
Work Done ◽  
Mating Conditions

Abstract The design of mechanical assemblies is mainly done after having modeled single parts. Most of the CAD systems are still weak for what concerns assembly. For example, they do not support the manipulation or the modification of the part geometry or the mating conditions once the assembly is made. The introduction of a feature-based approach in assembly design, successfully used in the design of single parts, would offer several advantages. This paper describes some results of the research work done within a project funded by the European Union aiming at extending the use of features, to help in the solution of assembly problems in the aeronautical applications.

Representing and Recognizing Features in Mechanical Designs

1990 ◽  
Author(s):  
Susan Finger ◽  
Scott A. Safier
Keyword(s):  
Graph Grammars ◽  
Design Environment ◽  
Geometric Models ◽  
Feature Based ◽  
Geometric Representations ◽  
Design Systems ◽  
High Level ◽  
Feature Based Design ◽  
Structural Engineers ◽  
Rough Surface Finish

Abstract When experts view an object, they perceive it in terms of their own expertise. For example, manufacturers see features that affect the processes used to fabricate a part, while structural engineers see sources of stresses and other features that tend to reduce the life of a part. Features can be geometric, such as slots or chamfers; they can be quantitative, such as distances between holes; they can be functional, such as alignment; or they can be qualitative, such as a rough surface finish. Research in feature-based design systems for mechanical designers has been motivated by the realization that geometric models represent the design in greater detail than can be utilized by designers, process planners, assembly planners, or by systems that emulate these activities. Features provide abstractions to facilitate the creation, representation, and analysis of designs. Our goal is to enable designers to compose mechanical designs from high-level features that embody functional and geometric properties. In addition, we want to provide designers with feedback on the manufacturability, assemblability, functionality, cost, etc. of the design as it evolves. To support this process in an intelligent CAD environment requires the integration of geometric models, analysis tools, and synthesis tools so that all aspects of the design can be considered while it is in progress. We are developing a design environment based on a shared representation of the design in which we can extract and reason about features of the design from different perspectives. Our approach is to represent both the design and the features using graph grammars. By representing the features using the same grammar as the design, we can recognize features by parsing a feature against the graph that represents the design. We are exploring grammars for behavior as well as geometry in order to provide a link between behavioral and geometric representations. In this paper, we focus on the representation and recognition of features.

A Design Method for Orthopedic Plates Based on Surface Features

2016 ◽  
Vol 139 (2) ◽  
Author(s):  
Lin Wang ◽  
Kunjin He ◽  
Zhengming Chen ◽  
Yin Yang
Keyword(s):  
Structural Strength ◽  
Design Method ◽  
Surface Feature ◽  
Feature Representation ◽  
Surface Model ◽  
Bone Surface ◽  
Element Analysis ◽  
Feature Based ◽  
Feature Based Design ◽  
Average Bone

Matching of orthopedic plates and bony surfaces does not have a high certainty of success because bone anatomy differs among individuals. Considering that surfaces of both orthopedic plates and bones manifest themselves as freeform surfaces and are especially suitable for surface feature-based design, a novel surface feature-based method for designing orthopedic plates is put forward, with detailed steps as follows. First, the bone surface feature (BSF) is established through feature representation of an average bone surface model, obtained based on the investigated samples. Second, the abutted surface of an orthopedic plate is established directly based on the BSF surface to increase matching between the plate and bony surface. The abutted surface feature (ASF) is then established through feature representation of the abutted surface. Third, the hierarchical mapping relationship between BSF and ASF is setup based on the framework of “three-level parameters and two-grade mappings.” The result is that semantic parameters defined on BSF and ASF are separated as an operation interface to make it convenient to edit orthopedic plates according to bone sizes. Finally, the orthopedic plate is generated by thickening the abutted surface, which is generated based on parameters defined on BSF. Taking radius as an example, a group of volar plates suitable for distal radius with different sizes are generated, showing that the proposed method is valid and feasible. Meanwhile, biomechanical stresses of designed volar plates are analyzed with finite element analysis, and the result shows that designed volar plates have good structural strength.

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