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The act of creating a new product, system, or process is an innovation; the result of excogitation, study and experimentation. It is an inductive and/or deductive process. The inductive process involves studying systems that exist, for example, in nature, patents and products, and inducing from the behavior of these systems elemental features for innovating novel products. The deductive process involves deducing such aspects from hypothetical concepts and situations where systems or products could exist. By the application of a combined inductive and deductive approach, this paper reports on a methodology for the creation of innovative products with a broader functional repertoire than traditional designs. This breed of innovative products is coined as transformers, transforming into different configurations or according to different states. Current design theory lacks a systematic methodology for the creation of products that have the ability to transform. This paper identifies analogies in nature, patents, and products along with hypothesizing the existence of such products in different environments and situations. Transformation design principles are extracted by studying key design features and functional elements that make up a transforming product. These principles are defined and categorized according to their roles in general transformations. The principles and categorizations are then validated and applied to conceptualize transforming products as part of an innovative design process. [DOI: 10.1115/1.3125205] Keywords: design principles, transformational design, design transformation theory, inductive research, deductive research

Functional testing of prototypes is a critical step in the development of many of today's products. Results of functional tests allow for verification of proper performance before a product is introduced into the market. The advent of rapid prototyping technologies offers engineers the potential to dramatically reduce the prototype-test-verify cycle and get products to market quickly. However, dimensional and material property limitations of rapid prototypes often prevent them from being used for functional testing without the use of similitude methods to correlate measured prototype behavior with predicted product behavior: The traditional similarity method (TSM), which is based on the Buckingham [PI] theorem, requires that the dimensionless parameters of the prototype and product systems be identical in order to correlate their states and accurately predict product performance. The requirement of identical dimensionless parameters' which is inherent in the TSM is often impossible to realize with the limited properties available from rapid prototyping technologies. In order to overcome this limitation, an empirical similarity method (ESM) has been developed. The general concept of the ESM is introduced along with an implementation procedure. Numerical and experimental examples are presented which demonstrate the feasibility and industrial impact of the ESM in the context of product design.

This paper presents the results of research attempts to substantiate repeatability and uniqueness claims of a functional model derivation method following a hypothesis generation and testing procedure outlined in design research literature. Three experiments are constructed and carried out with a participant pool that possesses a range of engineering design skill levels. The experiments test the utility of a functional model derivation method to produce repeatable functional models for a given product among different designers. In addition to this, uniqueness of the functional models produced by the participants is examined. Results indicate the method enhances repeatability and leads designers toward a unique functional model of a product. Shortcomings of the method and opportunities for improvement are also identified. [DOI: 10.1115/1.1625400]

During the design and development of new products, design engineers use many techniques to generate and define new and 'good' concepts. Inherent in this search for solutions is the conscious and unconscious reliance on prior experience and knowledge, or design-by-analogy. In this paper, a quantitative metric for design-by-analogy is developed. This metric is based on the functional similarity of products. By using this product-similarity metric, designers are able to formalize and quantify design-by-analogy techniques during concept and layout design. The methods, as developed in this paper, allow a designer with limited experience to develop sophisticated solutions that enhance the overall design of a new product. Also, a designer's current design-by-analogy vocabulary can be extended beyond his or her immediate experience, providing access and contributions to new domains by discovering different products with common functions. The similarity metric and its application are clarified and validated through a case study. The case study is the original design of a pickup winder. [DOI: 10.1115/1.1475317] Keywords: Design-by-Analogy, Product Similarity, Functional Analysis, Customer Needs, Novel Product Design

The status of fault patterns on part surfaces can provide valuable information about the condition of a manufacturing system. Accurate detection of the part surface condition in manufacturing ensures the fault-free manufacturing of high-quality parts, as well as helping in the accurate design/redesign of machine components and manufacturing parameters. To address this problem, we introduce an alternative mathematical transform that has the potential to detect faults in manufacturing machines by decomposing signals into individual components. Specifically, the paper focuses on the decomposition of numerically generated data using the Karhunen-Loeve transform to study a variety of signals from manufacturing. The potential utility of the proposed technique is then discussed in the context of understanding a manufacturing process under constant development.

In conventional rotordynamic modeling, hydrodynamic bearings are often characterized by a set of linear stiffness and damping coefficients obtained from a first-order Taylor series expansion of bearing reactions. Theoretically, these coefficients are only valid for small amplitude motion about an equilibrium position. In this paper, a nonlinear dynamic model that overcomes the small amplitude assumption in the conventional linear analysis is described. By including higher-order terms in the bearing reaction expansion, nonlinearity in the oil film forces for large amplitude motion can be captured and represented by a set of nonlinear stiffness and damping coefficients. These coefficients are functions of static bearing displacement. A finite difference approach is described and is used to solve for these coefficients. The stated model is applied to a conventional slider bearing and a mechanical smart slider bearing that experiences large variations in load. Error assessment is performed numerically on the higher-order solutions to determine an acceptable displacement bound for the higher order coefficients.

Most microelectromechanical systems (MEMS) designed today use macroscopic power supplies, thereby placing limits on the functionality of MEMS in many applications. An alternative to this approach is to design MEMS with integral microscopic distributed power supplies. This paper examines the feasibility of creating micro power supplies by considering three functions common to MEMS power systems: 1) capture energy; 2) store energy; and 3) drive actuation. Of these, only the capture energy function is highly dependent on the specific application. For each of the three functions, a table is presented which compares various means of performing the function. This information makes it possible to determine what design alternatives are feasible for the creation of a micro power supply for any specific application of MEMS. We use smart bearings with active surface features as an example application and develop a design for a micro power supply suitable for this work. Index Terms - Energy densities, micro power supplies, smart hydrodynamic bearings.

The submacrogeometric (tolerance) variations of mechanical components have an important impact on product function. The problem of combining tolerance assignment in engineering design with tolerance control in manufacturing and quality assurance presents a continuing challenge to researchers. This paper illustrates the feasibility of using fractal-based methods for the problem of tolerance specification in engineering design. Error data are generated as a function of the fractal dimension using the fractional Brownian motion model and are superposed on an ideal profile of a slider bearing. The consequent changes in performance parameters are studied and the detrimental effect of large variations perceived. This simple case study indicates the potential of the method to be extended for more complex problems.

Byline: Darren A. Keese, Carolyn C. Seepersad, Kristin L. Wood Product designers seek to create products that are not only robust for the current marketplace, but also flexible for future changes that may be unanticipated or unplanned. Very few techniques exist for understanding and assessing the flexibility of products for future change. In this paper, enhancements are presented for Change Modes and Effects Analysis (CMEA), a flexibility assessment tool that aids designers in meeting this goal. CMEA has been systematically enhanced to improve its ease of use and increase the consistency of its application for comparing or improving product flexibility. An example application of CMEA to an existing product, a consumer power gardening tool, is provided. This application demonstrates the potential usefulness of CMEA while highlighting the improved features of the technique.

Functional models represent a form independent blueprint of a product. As with any blueprint or schematic, a consistent language or coding system is required to ensure others can read it. This paper introduces such a design language, called a functional basis, where product function is characterized in a verb-object (function-flow) format. The set of functions and flows is intended to comprehensively describe the mechanical design space. Clear definitions are provided for each function and flow. The functional basis is compared to previous functional representations and is shown to subsume these attempts as well as offer a more consistent classification scheme. Applications to the areas of product architecture development, function structure generation, and design information archival and transmittal are discussed. [S1050-0472(00)00704-2]

This paper describes a signal analysis method using the Karhunen-Loeve (KL) transform, and applies the method to the analysis of hydrodynamic force data collected from controlled laboratory experiments. To demonstrate feasibility, the study focuses on inline forces induced on fixed cylinders exposed to oscillatory flows, with increasing Keulegan-Carpenter numbers. This preliminary example illustrates how this force makes a transition from the inertia-dominated region at low Keulegan-Carpenter numbers up into higher Keulegan-Carpenter numbers where the nonlinear effects of the flow-structure interaction can be observed through the increased influence of clearly defined modes. [S0892-7219(00)00603-8]