A System Architecture Approach to Global Product Development
Anshuman Tripathy, Steven Eppinger
Abstract: Recent advances in engineering collaboration tools and internet technology have enabled the distribution of product development tasks to offshore sites and global outsourcing partners while still maintaining a tightly connected process. Most firms in complex engineering industries are indeed experimenting with various ways to structure their product development processes on a global basis. In this research, we have explored global product development structures from the perspectives of process flow and system architecture. We employ the design structure matrix method to display and explain these structures and our observations thereof. Through five case studies spanning electronics, equipment, and aerospace industries, we consider the interaction complexity inherent in various global work distribution strategies. We conclude the paper with a summary and directions for future research work.
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A Network Approach to Define Modularity of Components in Complex Products
ASME Journal of Mechanical Design, forthcoming 2007
Manuel E. Sosa, Steven D. Eppinger, Craig M. Rowles
Abstract: Modularity has been defined at the product and system level, however little effort has gone into defining and quantifying modularity at the component level. We consider complex products as a network of components that share technical interfaces (or connections) in order to function as a whole and we define component modularity based on the lack of connectivity among them. Building upon previous work in graph theory and social network analysis, we define three measures of component modularity based on the notion of centrality. Our measures consider how components share direct interfaces with adjacent components, how design interfaces may propagate to non-adjacent components in the product, and how components may act as bridges among other components through their interfaces. We calculate and interpret all three measures of component modularity by studying the product architecture of a large commercial aircraft engine. We illustrate the use of these measures to test the impact of modularity on component redesign. Our results show that the relationship between component modularity and component redesign depends on the type of interfaces connecting product components. We also discuss directions for future work.
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A Network Approach to Define Modularity of Product Components
Proceedings of IDETC/CIE Conference, Long Beach, CA, September 2005
Manuel E. Sosa, Anupam Agrawal, Steven D. Eppinger, Craig M. Rowles
Abstract: We consider complex products as a network of components that share technical interfaces in order to function as a whole. Building upon previous work in graph theory and social network analysis, we define three measures of component modularity that consider how components may share direct interfaces with other adjacent components, how design interfaces may propagate to all other components in the product, and how components may act as “bridges” between other components. We calculate and interpret all three measures of component modularity by studying the actual product architecture of a large commercial aircraft engine. We illustrate how to use these measures to test their impact on component redesign. Directions for future work are discussed.
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A Simulation-Based Process Model for Managing Complex Design Projects
IEEE Transactions on Engineering Management, vol. 52, no. 3, pp. 316-328, August 2005
Soo-Haeng Cho, Steven D. Eppinger
Abstract: This paper presents a process modeling and analysis technique for managing complex design projects using advanced simulation. The model computes the probability distribution of lead time in a stochastic, resource-constrained project network where iterations take place among sequential, parallel, and overlapped tasks. The model uses the design structure matrix representation to capture the information flows between tasks. We use a simulation-based analysis to account for many realistic aspects of design process behavior which were not possible in previous analytical models. We propose a heuristic for the stochastic, resource-constrained project scheduling problem in an iterative project network. The model can be used for better project planning and control by identifying leverage points for process improvements, and for evaluating alternative planning and execution strategies. An industrial example is provided to illustrate the utility of the model.
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A
Methodology for Manufacturing Process Signature Analysis
Journal of Manufacturing Systems, Vol. 14, no. 1, pp. 20-34
January-February 1995
Steven D. Eppinger, Christopher D. Huber, Van H. Pham
Abstract:
Improvement of control systems entails collection of more information
about the process and/or more effective use of that information. We
present manufacturing process signature analysis to construct a relationship
between collected information (process signatures) and the quality of
process output, which can be used for on-line monitoring and control.
The general procedure consists of feature extraction, feature selection,
and classification. Extraction of large sets of features from signatures
is straightforward, and several classification schemes are available,
with neural networks being the most general and powerful. Feature selection,
however, is generally quite difficult for complex data structures. We
present several feature extraction methods and show that neural networks
can be useful in choosing different feature sets. Using a data set from
an automated solder joint inspection system, we demonstrate the unique
capabilities of neural networks for both feature selection and classification,
using more traditional statistical classification techniques as a benchmark.
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Systematic
versus Intuitive Problem Solving on the Shop Floor: Does it Matter?
MIT Sloan School of Management Working Paper 3716, November
1995
Marcie J. Tyre, Steven D. Eppinger, Eva M.H. Csizinsky
Abstract:
This paper examines the role of systematic problem solving
compared to more intuitive approaches in complex organizational settings.
Using a longitudinal study of problems encountered during the start-up
of Saturn Corporation’s new manufacturing facility, we address
four questions. 1) Does a systematic approach contribute to superior
problem solving outcomes in a manufacturing setting? 2) Does a systematic
problem solving approach take longer than more intuitive approaches?
3) When is a systematic approach most useful? 4) In what ways does problem
solving in real-world organizational settings depart from a systematic
model?
Our results suggest that a systematic problem solving approach not only
leads to better quality, more robust solutions under a wide variety
of situations, but also requires no more time than do more intuitive
approaches. We discuss implications of these findings for managers (such
as the need to encourage data-gathering at various stages during a problem
solving effort) and for theorists (notably, the need to reconcile these
findings with research that reveals the highly idiosyncratic, interactive,
and localized nature of problem solving in real organizations).
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Three Dynamic Problems in Robot Force Control
IEEE Transactions on Robotics and Automation, vol. 8, no.
6, pp. 751-758, December 1992
Steven D. Eppinger, Warren P. Seering
Abstract:
The dynamic characteristics of a mechanical system constrain
system performance. Three dynamic characteristics of robot systems are
discussed here: rigid-body bandwidth, dynamically noncolocated flexible
modes, and dynamically collocated flexible modes. All of these combine
to limit the closed-loop bandwidth achievable in the individual joint
control loops of the robot. They play a particularly important role
in establishing performance limits for robots under force control.
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Testing an Engineering Design Iteration Model in an Experimental Setting
ASME Conference on Design Theory and Methodology, Scottsdale,
AZ, pp. 267-276, September 1992
Robert P. Smith, Steven D. Eppinger, Amarnath Gopal
Abstracts:
In this paper, we compare two alternative design strategies
for the Delta Design Game, an engineering design exercise. We first
analyze these strategies using the Work Transformation Matrix, a design
iteration to display a faster solution time. We then demonstrate observing
eight design teams working on the problem using the two strategies.
We found that the “decoupling strategy” suggested by the
model reduced solution time while maintaining quality of the technical
solutions.
Keywords:
Design Methods and Models, Design Management
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Organizing the Tasks in Complex Design Projects: Development of Tools
to Represent Design Procedures
NSF Design and Manufacturing Systems Conference, Atlanta
GA, pp. 301-309, January 1992
Steven D. Eppinger, Daniel E. Whitney, David A. Gebala
Abstract:
This research is based upon the premise that in practice, design
procedures are rather methodical and can therefore be improved by analysis
and study of these procedures. In this paper, several network and matrix
modeling methodologies are presented and compared on their ability to
capture relevant information about design activities and on their ability
to provide insight into the performance of design processes. A detailed
description of these models and examples of each are provided for comparison.
We have found that the matrix models contribute significantly to our
understanding of current design practice and yield to analytical tools
which facilitate the formulation and implementation of improved procedures.
Limitations of the currently used models are identified, and enhanced
representation is proposed to overcome some of these limitations.
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Methods for Analyzing Design Procedures
ASME Conference on Design Theory and Methodology, Miami,
FL, pp. 227-233, September 1991
Steven D. Eppinger, David A. Gebala
Abstract:
This paper surveys several common models which can be used
to represent and study design procedures. A matrix representation of
design is discussed in detail and both new and existing analysis tools
are presented. Enhanced models are proposed to incorporate more information
into the matrix representation and to allow more sophisticate analysis
to be performed. The paper describes a testbed for the development and
testing of algorithmic analysis tools and concludes with suggestions
for further research into improving the design process.
Keywords:
Design Modeling, Design Management, Design StructureMatrix
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Interdisciplinary Product Design Education
IEEE Transactions on Engineering Management, vol. 37, no.
4, pp. 301-305, November 1990
Steven D. Eppinger, Charels H. Fine, Karl T. Ulrich
Abstract:
International competition has increased the demands on firms’
product design functions. Development teams are expected to create superior
products faster than ever. Educational programs must respond to this
need by training design professionals who can develop world-class products.
This article presents and approach to experiential education which has
succeeded at Massachusetts Institute of Technology (MIT) in motivating
both engineering and management students to orient their academic studies
and career plans towards design activities. Our course emphasizes that
product development is an interdisciplinary function requiring skills
that traditional departmental boundaries.
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Modeling and Experimental Evaluation of Asymmetric Pantograph Dynamics
ASME Journal of Dynamic Systems, Measurement, and Control,
vol. 110, pp. 168-174, June 1988
Steven D. Eppinger, D.N. O’Connor, W.P. Seering, D.N. Wormley
Abstracts:
High-performance pantograph design requires control of pantograph
dynamic performance. Many pantograph dynamic models developed to aid
in the design process have employed two degrees of freedom, on for the
head mass and one for the frame. In this paper, the applicability of
these models to symmetric and asymmetric pantograph designs is reviewed.
Two degree-of-freedom models have been shown to be appropriate to represent
a number of symmetric pantograph design. To represent the asymmetric
designs considered in this paper, an additional degree of freedom representing
frame dynamics has been introduced to yield a three degree-of-freedom
nonlinear dynamic performance model. The model has been evaluated with
experimental data obtained from laboratory dynamic testing of an asymmetric
pantograph.
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The Influence of Architecture in Engineering Systems
MIT Engineering Systems Monograph, March 2004
The ESD Architecture Committee: Edward Crawley, Olivier de Weck, Steven
Eppinger, Christopher, Joel Moses, Warren Seering, Joel Schindall, David
Wallace, Daniel Whitney (chair)
Abstract:
The field of Engineering Systems is distinguished from traditional engineering
design in part by the issues it brings to the top. Engineering Systems
focuses on abstractions like architecture and complexity, and defines
system boundaries very broadly. It also seeks to apply these concepts
to the process of creating systems. This paper summarizes the role and
influence of architecture in complex engineering systems. Using the
research literature and examples, this paper defines architecture, argues
for its importance as a determinant of system behavior, and reviews
its ability to help us understand and manage the design, operation,
and behaviors of complex engineering systems.
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Interdisciplinary Product Development Education at MIT and RISD
Design Management Journal, vol. 13, no. 3, pp. 58-61, Summer 2002
Steven D. Eppinger, Matthew S. Kressy
Abstract:
This popular course has a decade-long history. Students come from a
range of backgrounds and explore how teamwork and a cross-section of
talents are fundamental to the product design process. Steven Eppinger
and Matthew Kressy summarize the main features of their class, provide
examples of student projects, and thoroughly enumerate the lessons learned
in this demanding but exciting teaching exercise.
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Educating Product Development Leaders
Design Management Journal, vol. 3, no. 3, pp. 47-53, Summer
1992
Karl T. Ulrich and Steven D. Eppinger
Abstract: Product development is inherently interdisciplinary,
a process that includes contributions from engineers, marketers, industrial
designers, and many others. This reality stands in sharp contrast with
the traditions of academe, where the professions are separated. At MIT,
Karl Ulrich and Steven Eppinger have devised a course that more closely
mirrors corporate design management, where engineers and MBA students
are challenged as a team to apply decision-making methodologies to the
design and fabrication of an actual product.
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The Misalignment of Product Architecture and Organizational Structure
in Complex Product Development
Management Science, forthcoming
Manuel E. Sosa, Steven D. Eppinger, Craig M. Rowles
Abstract: Product architecture knowledge is typically embedded
in the communication patterns of established development organizations.
While this enables development of products using the existing architecture,
it hinders the organization’s ability to implement novel architectures,
especially for complex products. Structured methods addressing this
issue are lacking, as previous research has studied complex product
development from two separate perspectives: product architecture and
organizational structure. Our research integrates these viewpoints with
a structured approach to study how design interfaces in the product
architecture map onto communication patterns within the development
organization. We investigate how organizational and system boundaries,
design interface strength, indirect interactions, and system modularity
impact the alignment of design interfaces and team interactions. We
hypothesize and test how these factors explain the existence of the
following cases: 1) known design interfaces not addressed by team interactions
and 2) observed team interactions not predicted by design interfaces.
Our results offer important insights to managers dealing with interdependences
across organizational and functional boundaries. In particular, we show
how boundary effects moderate the impact of design interface strength
and indirect team interactions, and are contingent upon system modularity.
The research uses data collected from a large commercial aircraft engine
development process.
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Information Hiding in Product Development: The Design Churn Effect
MIT Sloan School of Management Working Paper, January 2002
Ali Yassine, Nitin Joglekar, Dan Braha, Steven Eppinger, Daniel Whitney
Abstract: Execution of a complex product development project
is facilitated through its decomposition into an interrelated set of
localized development tasks. When a local task is completed, its output
is integrated through an iterative cycle of system-wide integration
activities. Integration is often accompanied by inadvertent information
hiding due to the asynchronous information exchanges. We show that information
hiding leads to persistent recurrence of problems (termed as the design
churn effect) such that progress oscillates between being on schedule
and falling behind. The oscillatory nature of the PD process confounds
progress measurement and makes it difficult to judge whether the project
is on schedule or slipping. We develop a dynamic model of work transformation
to derive conditions under which churn is observed as an unintended
consequence of information hiding due to local and system task decomposition.
We illustrate these conditions with a case example from an automotive
development project and discuss strategies to mitigate design churn.