Marco Gero Fernández

Decision support in concurrent engineering - The utility-based selection decision support problem

Decisions are an important part of Concurrent Engineering and engineering design in general. Accordingly, more attention should be paid to the means and methods for making these decisions. In this article, a utility-based decision support method for the selection of an engineering design is presented. The utility-based selection decision support problem (u-sDSP) is a synthesized construct that facilitates selection decisions involving trade-offs among multiple, conflicting attributes and mitigation of risk associated with uncertain performance with respect to the attributes considered. The negative impact of unnecessary iterations on the product development cycle is reduced via the assurance of preference-consistent outcomes. Specifically, utility theory provides a mathematically rigorous means of clarifying and capturing designer preferences as well as identifying a preferred alternative in the context of stochastic uncertainty, while the selection decision support problem (DSP) – the construct within which utility theory is employed – facilitates the effective use of engineering judgment for (1) formulating and bounding decisions and (2) establishing a proper context. Application of the u-sDSP is illustrated with an example from rapid prototyping (RP), in which the goal is to select the appropriate technology and material combinations for testing the snap-fit design of a light switch cover plate assembly.

DESIGNING DESIGN PROCESSES IN PRODUCT LIFECYCLE MANAGEMENT: RESEARCH ISSUES AND STRATEGIES

Product Lifecycle Management (PLM) promises to further a holistic consideration of product design, emphasizing integration, interoperability, and sustainability throughout a product’s lifecycle. Thus far, efforts have focused on addressing lifecycle concerns from a product-centric perspective by exploiting the reusability and scalability of existing products through product platform and product family design. Not much attention has been paid to leveraging the design process and its design in addressing lifecycle considerations, however. In striving for sustainability, it is the design process that should be considered to constitute an engineering enterprise’s primary resource commitment. In this paper, an overview of the challenges inherent in designing design processes is provided. These challenges are subsequently illustrated with regard to several design scenarios of varying complexity, using an example involving the design of Linear Cellular Alloys. A distinction is made between product related requirements/goals and design process related requirements/goals. Requirements, research issues, and strategies for addressing the diverse needs of modeling design processes from a decision-centric perspective are established. Finally, key elements for enabling the integrated design of products and their underlying design processes in a systematic fashion are provided, motivating the extension of PLM to include the lifecycle considerations of design processes, thereby moving towards Design Process Lifecycle Management (DPLM).

Implications of a multi-disciplinary educational and research environment: Perspectives of future business, law, science, and engineering professionals in the technological innovation: Generating economic results (TI:GER®) program

Abstract Functioning well in a global, technology-driven, multi-disciplinary environment necessitates a more robust educational paradigm, especially in science and engineering. For a scientific education to be complete, it can no longer be restricted solely to technical areas. Similarly, law and business students will encounter a slew of technologies throughout the course of their careers. They will be required to comprehend the intricacies and corresponding implications of these technologies in order to impart their perspectives effectively and have an impact. In an effort to address this widely recognized need, a number of multi-disciplinary education and innovation programs have recently surfaced. Although several of these have been documented in the literature, the experiences of participants and the manner in which these will influence their future career plans as well as personal goals are not usually taken into account. Our focus in this paper is to shed light on this ‘end effect’ of being exposed to a multi-disciplinary education by stressing the importance of understanding social, economic, and legal aspects of science and engineering within the context of a scientific graduate-level education. Specifically, the authors take a closer look at the TI:GER® 1(Technological Innovation: Generating Economic Results) program. Based on their experiences, the authors present their learning and insight on multi-disciplinary education in a mixed technical and professional degree setting.

A Modular Decision-centric Approach for Reusable Design Processes:

The reusability of design processes modeled in existing Product Lifecycle Management (PLM) and Computer Aided Engineering (CAE) frameworks has been limited to the level of flow charts or activity-based diagrams that serve as planning and organizational aids. Current simulation-based design frameworks provide limited support for reuse of design processes at a level where design processes are networks of computational operations, specifically the capabilities to reuse (a) design processes for different products, and (b) collaborative design strategies. In this article, we address these limitations by providing a modeling approach for simulation-based design processes so that they can be archived in a generic modular fashion and reused for collaborative design of different products. The proposed approach is based on four foundations: (a) modeling design processes as hierarchical systems, (b) separation of declarative and procedural information, (c) modeling design processes as decision-centric activities, and (d) modeling interactions between decision makers using game theoretic protocols. These four fundamentals of the approach are instantiated in the form of generic computational templates for products, processes, decisions, and pertinent interfaces. The approach is illustrated using a proof of concept implementation in ModelCenter. The implementation is validated by showing the reusability of design processes for two different products, a spring and a pressure vessel, in individual and collaborative design scenarios. The approach has potential for supporting reusability of broader PLM processes.

Selection Without Reflection is a Risky Buisness ...

In engineering, designers are often faced with decisions involving conflicting objectives. Although existing Multi Criteria Decision Making (MCDM) “methods” can aid decisionmakers in satisfying the required trade-offs, a basic understanding of the assumptions and limitations underlying the approaches is required. It is important to note that all of these so called MCDM “methods” have fundamental shortcomings, which render them inappropriate for carte blanche application. Making an educated decision, as to which method to choose for a particular problem, however, is confounded by the fact that over 70 MCDM methods have thus far been proposed within the literature. Although many approaches, aimed at facilitating the selection of the most suitable MCDM approaches for a particular task, have been proposed, these are misleading since they suggest the existence of a “best” method for a particular problem at hand. The very description of the MCDM techniques as methods is a misnomer, as the majority of them constitutes nothing more than attention directing tools and should be treated as such -with caution. Nevertheless, these attention directing tools, when used appropriately in a proper context, may have a significant amount of utility. It is for this reason that we advocate careful reflection (with regard to the problem at hand, the underlying assumptions/limitations of the attention directing tool considered, and interpretation of results) before selection.

Foundations for a systems-based approach for materials design

Establishing systems-based materials design methods is an important step towards enabling rapid, concurrent design of materials and products with the potential for significant technological innovations. Materials design involves tailoring material structures and processing paths to achieve properties and performance levels that are customized for a particular application. It is a complex, non-deterministic, multi-scale, multifunctional activity that requires multiple collaborating designers and distributed, heterogeneous computing resources. Accordingly, a systems-based design approach is required with which to manage information flows, embed performance-property-structure-processing relations, interrogate models, explore variability, and engage collaborative decision-support protocols. In this paper, we discuss some of the intellectual and computing foundations of our systemsbased approach for materials design. It has three primary facets: (1) a decision support framework for modeling and supporting a complex, collaborative design process, (2) robust design methods for modeling uncertainty and managing or minimizing its impact on design specifications, and (3) a computational infrastructure for integrating and sharing heterogeneous information and computing and software resources. Some of the key aspects of our approach are illustrated via design of multifunctional cellular materials for a structural heat exchanger application.

ON A DECISION SUPPORT FRAMEWORK FOR DISTRIBUTED COLLABORATIVE DESIGN AND MANUFACTURE

Modern realities have dictated a paradigm shift in design and manufacture practices towards distributed collaborative efforts. Such efforts at globalized synergy, however, invariably result in information intensive knowledge transfers, requiring not only information management but also deliberate structuring of decisions. This is of special concern in product development, where the interfaces between distinct phases of a design process are not well defined and largely misunderstood. The complexity of related design decisions is substantial. Bandwidth of information in knowledge transfers, high fidelity analyses, and ambiguity associated with interactions among distributed stakeholders engaged in shared, concurrent design tasks further complicate the matter. The result is poor communication, problematic changeovers, and hard-to- manufacture designs. Resulting design processes tend to be iterative and not only increase product development costs and extend time-to-market, but also ultimately impede collaboration. The roles of designers as decision-makers have consequently been occluded and there is a need for consistent decision support throughout the design process. In this paper, we present the concept of a Decision Support Framework for Distributed Collaborative Design and Manufacture. The focus is on providing designers with the means to model, structure, negotiate solutions to, and interface multi-attribute decisions, considering tradeoff in the context of risk and uncertainty.

CONCISE INTERACTIONS AND EFFECTIVE MANAGEMENT OF SHARED DESIGN SPACES - MOVING BEYOND STRATEGIC COLLABORATION TOWARDS CO-DESIGN

Often, design problems are coupled and their concurrent resolution by interacting stakeholders is required. The ensuing interactions are characterized predominantly by degree of interdependence and level of cooperation. Since tradeoffs, made within and among sub-systems, inherently contribute to system level performance, bridging the associated gaps is crucial. With this in mind, effective collaboration, centered on continued communication, concise coordination, and non-biased achievement of system level objectives, is becoming increasingly important. Thus far, research in distributed and decentralized decision-making has focused primarily on conflict resolution. Game theoretic protocols and negotiation tactics have been used extensively as a means of making the required tradeoffs, often in a manner that emphasizes the maximization of stakeholder (personal) payoff over system level performance. More importantly, virtually all of the currently instantiated mechanisms are based upon the a priori assumption of the existence of solutions that are acceptable to all interacting parties. No explicit consideration has been given thus far to ensuring the convergence of stakeholder design activities leading up to the coupled decision and the associated determination of values for uncoupled and coupled design parameters. Consequently, unnecessary and costly iteration is likely to result from mismatched objectives. In this paper, we advocate moving beyond strategic collaboration towards co-design. We present an alternative coordination mechanism, centered on sharing key pieces of information throughout the process of determining a solution to a coupled system. Specifically, we focus on (1) establishing and assessing collaborative design spaces, (2) identifying and exploring regions of acceptable performance, and (3) preserving stakeholder dominion over design sub-system resolution throughout the duration of a given design process. The fundamental goal is to establish a consistent framework for goal-oriented collaboration that (1) more accurately represents the mechanics underlying product development and (2) facilitates interacting stakeholders in achieving their respective objectives in light of system level priorities. This is accomplished via improved utilization of shared resources and avoidance of unnecessary reductions in design freedom. Comparative performance of the proposed method is established using a simple example, involving the resolution of a tradeoff with respect to a system of non-linear equations.Copyright

FACILITATING META-DESIGN VIA SEPARATION OF PROBLEM, PRODUCT, AND PROCESS INFORMATION

Different products necessitate different design processes. Determining which such process is most appropriate for a particular product, in turn, requires its delineation before the design of the product under consideration. The phase where design processes are composed is called meta-design. Despite its importance, current simulation-based design frameworks such as FIPER, ModelCenter, and iSIGHT do not support meta-design. This oversight can be attributed at least in part to the fact that these frameworks capture information about products, design processes, and the associated tools in a lumped fashion. Processes are captured in terms of the specific tools employed and the product information, associated with their use, thereby restricting the re-utilization (i.e., reuse via adaptation or customization) of instantiated processes for designing different products. This inherent inability to separate product and process information hinders the exploration of different design process options for designing a product at a fundamental level, thereby restricting meta-design. In order to address this challenge, we propose an approach for distinctly capturing and processing three key components of design related information - a) design problem, b) design process, and c) product. We term this approach, rooted in decision-based design, modularity, and separation of declarative and procedural information, 3-P. The modular separation of information associated with problem, product, and process enables designers to utilize existing knowledge, captured in the form of pre-defined process configurations, for more effectively designing a given product. The proposed approach facilitates the efficient exploration and reconfiguration of design processes, furnishing a much needed and essential basis for meta-design.

Digital Interfaces: The Key to Effective Decision-Making in Distributed Collaborative Design and Manufacturing

In product development, the interfaces between distinct phases of a design process are not well defined and largely misunderstood. The same ambiguity holds true for interactions among distributed stakeholders engaged in shared, concurrent design tasks. Such vagueness fosters poor communication, problematic changeovers, and hard-to-manufacture designs. Resulting design processes tend to be iterative and not only increase product development costs and extend time-to-market, but also ultimately impede collaboration. What is needed is the ability to propagate decision-critical, up-to-date information alongside design knowledge for both sequential and concurrent design tasks. This is particularly important for dependent and interdependent decisions that cannot be made in isolation. To address this need, digital interfaces are being developed as key components to successful collaboration in distributed design and manufacture applications. Such digital interfaces will constitute a means of communicating critical information and will address the need for allocating responsibility for decisions. The potential implementation of a digital interface is illustrated in an example focusing on the production of a functional prototype of a disposable camera spool.© 2002 ASME