Steven J. Fenves

A foundation for interoperability in next-generation product development systems

United States industry spends billions of dollars as a result of poor interoperability between computer-aided engineering software tools. While ongoing standards development efforts are attempting to address this problem in todays tools, the more significant demand in next-generation tools will be for representations that allow information used or generated during various product development activities to feed forward and backward into others by way of direct electronic interchange. Although the next generation of tools has the potential for greatly increased benefits, there is also a potential for the cost of poor interoperability to multiply. The goal of this work is to develop representations of information that are unavailable in traditional computer-aided engineering tools to support the exchange of product information in a distributed product development environment. This paper develops a vision of next-generation product development systems and provides a core representation for product development information on which future systems can be built.

Information sharing and exchange in the context of product lifecycle management: Role of standards

This paper introduces a model of the information flows in Product Life cycle Management (PLM), serving as the basis for understanding the role of standards in PLM support systems. Support of PLM requires a set of complementary and interoperable standards that cover the full range of aspects of the products life cycle. The paper identifies a typology of standards relevant to PLM support that addresses the hierarchy of existing and evolving standards and their usage and identifies a suite of standards supporting the exchange of product, process, operations and supply chain information. A case study illustrating the use of PLM standards in a large organization is presented. The potential role of harmonization among PLM support standards is described and a proposal is made for using open standards and open source models for this important activity.

CPM2: A Core Model for Product Data

The initial core product model (CPM), developed at NIST for the support of in-house research projects, has been extended to create CPM2, intended to support a broad range of information relevant to product lifecycle management. CPM2 is a generic, abstract model with generic semantics. CPM2 gives equal status to three aspects of a product or artifact: its function, its form, and its behavior. Thus, CPM2 can support functional reasoning about a product in the conceptual stages of design, the recording and the modeling of its behavior in the postdesign stages as well as the traditional design phases. Three levels of CPM2 models, denoted as the conceptual, intermediate, and implementation models, are described. Extensions of the initial CPM are briefly presented. The facilities in CPM2 for building experimental intermediate systems are demonstrated and a short illustrative example is given. The full practical evaluation of CPM2 will require the development and use of implementation models.

Product lifecycle management support: a challenge in supporting product design and manufacturing in a networked economy

In this paper, we provide an overview of the changing design and manufacturing landscape in the 21st century that has come about because of IT and the changing global conditions. Based on this overview and a review of the current state of IT for PLM support in the design and manufacturing sector, we identify the areas of need for standards. A review of areas covered by standards leads us to the development of an initial typology of standards and a potential path for bringing convergence of these standards in support of PLM. We make a case throughout the paper that given the nature of the task we need to aspire to create open standards with wide participation. We conclude by arguing that there is an important role to be played in this context by institutions such as NIST as a neutral party in the standards debates and implementations.

SEED-Config: a tool for conceptual structural design in a collaborative building design environment

Abstract SEED-Config is a design environment intended to assist structural designers in collaboratively exploring and extending the design buildings. Its purpose is to help designers in rapidly synthesizing alternative structural design solutions at the conceptual level to the point where the structural concept is supportive of the overall design and possible conflicts are explored and resolved. The SEED-Config prototype consists of four subsystems. The Design Information Repository is built upon an information model that exploits the hierarchical nature of building descriptions to represent design information. It can save an overall design or parts of a design to a case library, thus supporting case-based reasoning. The Design Knowledge Manager allows for the browsing, editing, selecting and applying of technology nodes which encapsulate structural design knowledge. The Classification Reference Manager allows for the definition, management, inference and querying of classifications which are used to classify and index design solutions as they are generated. The Geometric Modeler reasons about topology and geometry.

A Model for the Flow of Design Information in Product Development

The complexity of modern products and design tools has made the exchange of design information more complex. It is widely recognised that the seamless capture, storage, and retrieval of design information is one of the major challenges for the next generation of computer aided design tools. This paper presents a model for the flow of design information that is sufficiently formal to eventually support a semantics-based approach for developing information exchange standards. The model classifies design information into various types, organises these types into information states and levels of abstraction, and identifies the various transformations that operate within and between the information states. The model’s ability to support a variety of design process models is illustrated by applying it to the Systems Integration of Manufacturing Applications (SIMA) design process model, and the model is then applied to a design example.

A Semantic Product Modeling Framework and Its Application to Behavior Evaluation

Supporting different stakeholder viewpoints across the product lifecycle requires semantic richness to represent product-related information and enable multiview engineering simulations. This paper proposes a multilevel product modeling framework enabling stakeholders to define product models and relate them to physical or simulated instances. The framework is defined within the Model-Driven Architecture using the multilevel (data, model, metamodel) approach. The data level represents real-world products, the model level describes models (product models) of real-world products, and the metamodel level describes models of the product models. The metamodel defined in this paper is specialized from a web ontology language enabling product designers to express the semantics of product models in an engineering-friendly way. The interactions between these three levels are described to show how each level in the framework is used in a product engineering context. A product design scenario and user interface for the product metamodel is provided for further understanding of the framework.

Extending the notion of quality from physical metrology to information and sustainability

In this paper we intend to demonstrate the need for extending the notion of quality from the physical domain to information and, more comprehensively, to sustainability. In physical metrology there are well established principles such as fundamental units, precision, accuracy, traceability and uncertainty. In order to understand and define quality for information and sustainability we need to develop metrological concepts similar to those of physical metrology. Research efforts related to information quality (IQ) are scattered. IQ is primarily defined in terms of several characteristics (dimensions) which lack consensus definitions and are sometimes subjective. However, the notion of IQ is currently in practice and has provided some useful insights towards defining formal approaches to IQ. In order to extend the notion of quality to sustainability we need, as in the case of information, a well defined metrology similar to physical metrology. Sustainability is currently getting attention in many areas of human endeavor. One proposal is to measure sustainability in terms of a triple bottom line, namely social, economical and environmental aspects of human endeavor. Sustainability metrics are continuously evolving and their clear definition is fundamental to the understanding of the notion of sustainability quality. As an example we consider evaluation of carbon footprint, as a metric towards sustainability, for manufacturing a simple turned part. After analyzing the current literature, we identify the following needs for characterizing the notion of sustainability quality: (a) standardized terminology of terms and concepts, (b) metrics and metrology, (c) harmonization and extension of standards, (d) conformance testbeds for standards and (e) development of information models that support sustainability.

Description Logic for Product Information Models

The languages and logical formalisms developed by information scientists and logicians concentrate on the theory of languages and logical theorem proving. These languages, when used by domain experts to represent their domain of discourse, most often have issues related to the level of expressiveness of the languages and need specific extensions. In this paper we analyze the levels of logical formalisms and expressivity requirements for the development of ontologies for manufacturing products. We first discuss why the representation of a product model is inherently complex and prone to inconsistencies. We then explore how these issues can be overcome through a structured knowledge representation model. We report our evaluation of OWL-DL in terms of expressivity and of the use of SWRL for representing domainspecific rules. We present a case study of product assembly to document this evaluation and further show how the OWL-DL reasoner together with the rule engine can enable reasoning of the product ontology.

TOWARDS MODELING THE EVOLUTION OF PRODUCT FAMILIES

A strategy successfully used by manufacturing companies is to develop product families so as to offer a variety of products with reduced development costs. This paper introduces our initial research on the representation of the evolution of product families and of the rationale of the changes involved. The information model representing product families is an extension of the NIST Core Product Model and consists of three submodels: Product Family, Family Evolution, and Evolution Rationale. In addition, a Unified Modeling Language (UML)-based representation and a prototype implementation of the conceptual model are introduced.Copyright