Predictabilty of Change in Engineering: A Complexity View

Design changes can be surprisingly complex. We examine the problems they cause and discuss the problems involved in predicting how changes propagate, based on empirical studies. To assist this analysis we distinguish between (a) a static background of connectivities (b) descriptions of designs, processes, resources and requirements and (c) the dynamics of design tasks acting on descriptions. The background might consist of existing designs and subsystems, or established processes used to create them. The predictability of design change is examined in terms of this model, especially the types and scope of uncertainties and where complexities arise. An industrial example of change propagation is presented in terms of the background (connectivity) - description - action model.

Affordances in Product Architecture: Linking Technical Functions and Users’ Tasks

Developing usable and desirable products requires an understanding of how users build close relationships with objects and how these relationships can be controlled by developers. This paper discusses the importance of the concept of affordances as an instrument useful for understanding the relationships between technical functions and user tasks. The approach introduces a Function-Task Design Matrix to link technical functions with user tasks and to capture relevant affordance-level requirements throughout the product architecture generation. Functional and Operational Affordance levels are introduced to help determine the product attributes necessary to optimize the ease with which users can undertake technical functions. The paper uses functional language, focusing attention towards the use of the product, rather then merely its workings. The tools for describing affordances are described first, followed by a step-by-step description of how they can be used to improve decisions during product architecture generation. The mechanism is illustrated in a case study on a kitchen appliance.

Analyzing Module Commonality for Platform Design in Functional and Physical Domain

Product platforms can provide many advantages from cost savings to a large variety of products with less effort than without platforms. The key choice in modular platform design is the choice of common platform modules. We developed an algorithm to aid in this choice. The algorithm is based on calculating the distance between function inputs and outputs, in the functional domain, or component attributes, in the physical domain. Unlike other methods before, this method can identify commonalities from any or mixed degrees of decomposition and it is not limited to a single measure of commonality. In addition we analyze the degree of commonality quantitatively. The common module candidates are clustered to a hierarchical dendrogram that serves as a decision tool for the designer. It is shown how the algorithm identifies common module candidates for a family of sensors in the functional domain and for a family of micro machines in the physical domain.

Limitations of Parametric Operators for Supporting Systematic Design

Computers are being used extensively in the manufacturing industry to design and analyze products. In spite of the power of existing CAD systems and potential power of current Design Automation systems, we believe that they possess an inherent limitation that keeps them from aligning with and fully supporting the design process. Specifically, all of these systems are based on using parametric operators to generate valid designs. This paper examines the limitations of parametric operators for CAD and design automation and shows how “variational” methods could be used. An approach using variational methods is compared with traditional CAD and design automation methods. The paper also proposes a language of objects and relationships to represent design requirements. This work is a step towards realizing an interactive design synthesis system that can represent and satisfy design requirements.

Towards Rapid Redesign: Decomposition Patterns for Large-Scale and Complex Redesign Problems

In an effort to develop a decomposition-based rapid redesign methodology, this paper introduces the basis of such a methodology on decomposition patterns for a general redesign problem that is computation-intensive and simulation-complex. In particular, through pattern representation and quantification, this paper elaborates the role and utility of the decomposition patterns in decomposition-based rapid redesign. In pattern representation, it shows how a decomposition pattern can be used to capture and portray the intrinsic properties of a redesign problem. Thus, through pattern synthesis, the collection of proper decomposition patterns allows one to effectively represent in a concise form the complete body of redesign knowledge covering all redesign problem types. In pattern quantification, it shows how a decomposition pattern can be used to extract and convey the quantum information of a redesign problem using the pattern characteristics. Thus, through pattern analysis, the formulation of an index incorporating two redesign metrics allows one to efficiently predict in a simple manner the amount of potential redesign effort for a given redesign problem. This work represents a breakthrough in extending the decomposition-based solution approach to computational redesign problems.

Infused Creativity: An Approach to Creative System Design

Many methods that support human creativity by manual or computational means have been proposed in the past. They rely on the assumption that following a certain process of reasoning might lead to generating ideas considered creative. We start by defining creativity as a capability that enables the creation of systems that are patentable. Subsequently, we present a method called infused creativity, which is derived from infused design. The method guarantees generating creative designs by transforming systems from remote disciplines. Finding these systems and their transformations is done through a provably guaranteed to work process based on the underlying discrete mathematical representation. We describe the method of infused creativity and illustrate its operation in designing a new active torque amplifier system. We also discuss the future development of the method.