A Constraint-Based Approach to the Composition Relation Management of a Product Class in Design

2010 ◽  
Vol 10 (3) ◽  
Author(s):  
Pierre-Alain Yvars
Keyword(s):  
Constraint Satisfaction Problems ◽  
Product Class ◽  
Product Modeling ◽  
Formal Representation ◽  
Connecting Rod ◽  
Product Model ◽  
Architectural Model ◽  
Programming Techniques ◽  
Combinatorial System ◽  
Composition Relation

The choice of solution, which a systems architect is confronted with within the framework of a product structure definition, can very quickly prove to be a thorny problem owing to the possible combinatorial system. In this paper, we will offer an alternative resting on the utilization of constraint-based programming techniques for representing and managing such complexity. More precisely, we will dwell on the presentation of a constraint-based approach to the composition relation management of a product class in design. After setting forth all the potential of the constraint-based approach, we will formally explain, in more detail, the six types of relations that seem to be essential to building a class of products. The approach is based on a three-level architectural model. The first level concerns the product model as such, the second supplies a formal representation of this model, whereas the third consists of rendering an arithmetic constraint-based approach to the intermediate model. We will use the discrete constraint satisfaction problems for operating and solving the latter. Our overall approach, from product modeling to resolution, is intended to be a generic one and the case in point will be the design of a functional pivot link between a connecting rod and a piston. The architect can subsequently make his own choices and the tool will automate their propagation by means of the constraint network modeling the problem. A dimensioning architectural model is, thus, obtained in compliance with the original list of requirements.

scholarly journals A fine-grained arc-consistency algorithm for non-normalized constraint satisfaction problems

2011 ◽  
Vol 21 (4) ◽  
pp. 733-744 ◽  
Author(s):  
Marlene Arangú ◽  
Miguel Salido
Keyword(s):  
Constraint Satisfaction ◽  
Constraint Programming ◽  
Real Life ◽  
Search Space ◽  
Constraint Satisfaction Problems ◽  
Fine Grained ◽  
Arc Consistency ◽  
Life Problems ◽  
Programming Techniques ◽  
Np Complete

A fine-grained arc-consistency algorithm for non-normalized constraint satisfaction problems Constraint programming is a powerful software technology for solving numerous real-life problems. Many of these problems can be modeled as Constraint Satisfaction Problems (CSPs) and solved using constraint programming techniques. However, solving a CSP is NP-complete so filtering techniques to reduce the search space are still necessary. Arc-consistency algorithms are widely used to prune the search space. The concept of arc-consistency is bidirectional, i.e., it must be ensured in both directions of the constraint (direct and inverse constraints). Two of the most well-known and frequently used arc-consistency algorithms for filtering CSPs are AC3 and AC4. These algorithms repeatedly carry out revisions and require support checks for identifying and deleting all unsupported values from the domains. Nevertheless, many revisions are ineffective, i.e., they cannot delete any value and consume a lot of checks and time. In this paper, we present AC4-OP, an optimized version of AC4 that manages the binary and non-normalized constraints in only one direction, storing the inverse founded supports for their later evaluation. Thus, it reduces the propagation phase avoiding unnecessary or ineffective checking. The use of AC4-OP reduces the number of constraint checks by 50% while pruning the same search space as AC4. The evaluation section shows the improvement of AC4-OP over AC4, AC6 and AC7 in random and non-normalized instances.

A Computational Product Model for Conceptual Design Using SysML

2009 ◽  
Author(s):  
Stefan Wo¨lkl ◽  
Kristina Shea
Keyword(s):  
Product Development ◽  
Conceptual Design ◽  
Mechanical Design ◽  
System Development ◽  
Concept Design ◽  
Product Modeling ◽  
Product Model ◽  
Mechatronic Systems ◽  
Starting Point

The importance of the concept development phase in product development is contradictory to the level and amount of current computer-based support for it, especially with regards to mechanical design. Paper-based methods for conceptual design offer a far greater level of maturity and familiarity than current computational methods. Engineers usually work with software designed to address only a single stage of the concept design phase, such as requirements management tools. Integration with software covering other stages, e.g. functional modeling, is generally poor. Using the requirements for concept models outlined in the VDI 2221 guideline for systematic product development as a starting point, the authors propose an integrated product model constructed using the Systems Modeling Language (SysML) that moves beyond geometry to integrate all necessary aspects for conceptual design. These include requirements, functions and function structures, working principles and their structures as well as physical effects. In order to explore the applicability of SysML for mechanical design, a case study on the design of a passenger car’s luggage compartment cover is presented. The case study shows that many different SysML diagram types are suitable for formal modeling in mechanical concept design, though they were originally defined for software and control system development. It is then proposed that the creation and use of libraries defining generic as well as more complicated templates raises efficiency in modeling. The use of diagrams and their semantics for conceptual modeling make SysML a strong candidate for integrated product modeling of mechanical as well as mechatronic systems.

scholarly journals A Collaborative Framework for Integrated Part and Assembly Modeling

2002 ◽  
Vol 2 (4) ◽  
pp. 256-264 ◽  
Author(s):  
Rafael Bidarra ◽  
Niels Kranendonk ◽  
Alex Noort ◽  
Willem F. Bronsvoort
Keyword(s):  
Feature Modeling ◽  
Product Modeling ◽  
Product Model ◽  
Team Members ◽  
Assembly Modeling ◽  
Distributed Development ◽  
Assembly Design ◽  
Multiple View ◽  
Actual Design ◽  
Collaborative Sessions

An ideal product modeling system should support both part modeling and assembly modeling, instead of just either of them as is the case in most current CAD systems. A good basis for such integration is multiple-view feature modeling, as it allows focusing on different aspects of the product, while at the same time maintaining consistency of all model views. This paper presents a framework that supports synchronous collaborative sessions via Internet, among members of a distributed development team, with such a modeling system. The framework provides facilities for creating a hierarchical product structure, with single and compound components, and meanwhile assigning tasks to team members. The actual design of a single component is supported by a web-client specialized in part design, whereas the specification of assembly relations among components is supported by a web-client specialized in assembly design. All clients make use of the same server, which runs a multiple-view feature modeling system and maintains the complete product model, guaranteeing consistency of the part design and the assembly design views.

Validity Maintenance for Freeform Feature Modeling

2010 ◽  
Vol 10 (1) ◽  
Author(s):  
Eelco van den Berg ◽  
Willem F. Bronsvoort
Keyword(s):  
Emerging Technology ◽  
Feature Modeling ◽  
Product Modeling ◽  
Feature Models ◽  
Product Model ◽  
Geometric Information ◽  
Single Product ◽  
Maximum Curvature ◽  
Curvature Constraint

Feature modeling is nowadays the predominant way of product modeling. Functional and geometric information are stored in a single product model, consisting of features such as holes, slots, and ribs. An emerging technology is the application of concepts of feature modeling to freeform shapes. Of particular importance here is that there are often many validity conditions, or constraints, that the resulting freeform feature models should satisfy. An example of this is a maximum curvature constraint on the faces of a particular feature. This paper presents an approach to specify and maintain such validity conditions for freeform feature models.

Study of Product Modeling Method Based on UML

2009 ◽  
Vol 419-420 ◽  
pp. 765-768
Author(s):  
Hai Tao Zhu ◽  
Wen Lin Pan ◽  
Chao Liu
Keyword(s):  
Product Life Cycle ◽  
Modeling Method ◽  
Model Structure ◽  
Product Modeling ◽  
Practical Application ◽  
Product Model ◽  
Meta Model ◽  
Consistency Problem ◽  
Definition Of ◽  
Model Layer

The product modeling method based on UML is presented in order to solve the consistency problem of definition, process and resources in the product life-cycle, and meet the need of developing the system from various viewports. Through the definition of three-layer product model structure included “product meta-meta model layer”, “product meta model layer” and the “product model layer” and its contents and their interrelation, the definition of a product modeling and constraint unity have been achieved to. The practical application reflects the validity and the feasibility of UML-based product modeling method.

Parametric Computer Aided Hydraulic Cylinder Design: Cylinder Product Modeling

1990 ◽  
Author(s):  
Hans L. Johannesson
Keyword(s):  
Data Base ◽  
Hydraulic Cylinder ◽  
Independent Data ◽  
Product Modeling ◽  
Product Model ◽  
Data Bases ◽  
Cad System ◽  
Wire Frame ◽  
Data Base Management System ◽  
Base Management

Abstract In a hydraulic cylinder each cylinder component contributes to the total function, and the components interact and are dependent on each other. The geometry of some components can be completely determined by other surrounding interacting components. In this work it is shown how computer aid can be applied in hydraulic cylinder design when considering component interaction. A special hydraulic cylinder product model is developed. It is stored in an external CAD system independent data base. The parameters stored in the data base are used when retrieving component data from component family data bases, standard component data bases, and when running parametric component and system design programs. The software system used in this work consists of an ordinary 2D wire frame modeling turn-key CAD system, FORTRAN application programs, a data base management system, CAD system independent data bases and CAD system dependent interface programs.

Study of Toleranced Products Modeling Based on Virtual Reality

2009 ◽  
Vol 16-19 ◽  
pp. 781-785 ◽  
Author(s):  
Gang Wei Cui ◽  
Ying Xue Yao ◽  
Yu Wang
Keyword(s):  
Virtual Reality ◽  
Information Integration ◽  
Low Cost ◽  
Geometric Model ◽  
Virtual Assembly ◽  
Product Modeling ◽  
Product Model ◽  
Special Software ◽  
Model Transform ◽  
Cad Cam

Virtual assembly based on the virtual reality gives a low-cost and rapid prototyping method for products’ assembly, and tolerances have become a key technique of information integration in CAD/CAM. It will be a new task about how to integrate tolerances into virtual assembly. A toleranced product model based on the virtual reality is constructed for the virtual assembly, and the essential data is saved and managed in database. Model transform interface software is developed, which is a special software that users can get the essential data without any users’ acting. The geometric model of products is constructed in the virtual reality, and the method of getting assembly information, dimensions, and tolerances is proposed. A toleranced product modeling system based on the virtual reality is developed, and the using of tolerances is discussed by an example.

Formal Representation of Product Design Specifications for Validating Product Design

2009 ◽  
Author(s):  
Alexander Weissman ◽  
Satyandra K. Gupta ◽  
Xenia Fiorentini ◽  
Rachuri Sudarsan ◽  
Ram Sriram
Keyword(s):  
Product Design ◽  
Formal Model ◽  
Mechanical Design ◽  
Design Solution ◽  
Formal Representation ◽  
Product Model ◽  
Formal Approach ◽  
Final Design ◽  
Consumer Device ◽  
Collaborative Efforts

As collaborative efforts in electro-mechanical design have scaled to large, distributed groups working for years on a single product, an increasingly large gulf has developed between the original stated goals of the project and the final design solution. It has thus become necessary to validate the final design solution against a set of requirements to ensure that these goals have, in fact, been met. This process has become tedious for complex products with hundreds of design aspects and requirements. By formalizing the representation of requirements and the design solution, tools can be developed to a large extent automatically perform this validation. In this paper, we propose a formal approach for relating product requirements to the design solution. First, we present a formal model for representing product requirements. Then, we introduce the Core Product Model (CPM) and the Open Assembly Model (OAM) for representing the design solution. Finally, we link these models formally and provide an example with an actual consumer device.

Research on the Application of Parametric Technology on Product Modeling

2011 ◽  
Vol 121-126 ◽  
pp. 4651-4655
Author(s):  
De Fang Liu ◽  
Li Ying Li ◽  
Jie Tao ◽  
Bin Wang
Keyword(s):  
Parametric Modeling ◽  
National Standards ◽  
Secondary Development ◽  
Product Modeling ◽  
Part Family ◽  
Key Technology ◽  
Programming Techniques

Part family and NX/Open programming techniques which are two kinds of parametric technology used in product modeling based on NX platform are introduced in this paper. The template of 3D part library was created on the base of analysis of different national standards. The key technology of product secondary development was narrated in detail, and the operation interface was created. Finally, a case was employed to testify the feasibility and efficiency of these two parametric modeling technologies.

Multidisciplinary Collaborative Product Modeling in Distributed Network Environment

2010 ◽  
Vol 97-101 ◽  
pp. 3708-3713
Author(s):  
Wen Qing Zhu ◽  
Liang Chen
Keyword(s):  
Collaborative Design ◽  
Product Information ◽  
Object Oriented ◽  
Multiple Views ◽  
Distributed Network ◽  
Network Environment ◽  
Product Modeling ◽  
Product Model ◽  
Information Interaction ◽  
Extended Object

Based on the analysis of product model characteristics of multidisciplinary collaborative design (MCD), multiple views model expressed by an extended object-oriented method is introduced to satisfy the requirements of different discipline designers for product information interaction and share. A product modeling system for multidisciplinary collaborative design is proposed, and the modeling method of discipline view model under the network environment is given, which can effectively support the evolution of product model and improve the flexibility of product modeling. The clutch is illustrated to validate the proposed methods.

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