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The Need to Bridge Design, Materials, and Production
The realization of complex products requires a huge amount of knowledge about customers' needs, the characteristics of technologies, the properties of materials, and the capabilities of manufacturing methods. The capabilities of different firms in different countries also must be known and compared. Bringing complex products to market or complex weapon systems to users in a short time at reasonable cost is a long-lasting concern and one that will become more acute in the future.
This report investigates potential as well as the recognized accomplishments of information technology to enhance the process of communication between customers, engineers, and manufacturers, in short, to strengthen the bridge between design and manufacturing of goods. In this chapter, the committee looks at prior approaches to this important issue and sketches a vision for the future.
HISTORY AND STATUS
Over the years, what is called "bridging" in this report has been called concurrent engineering, concurrent design, design for manufacturing and assembly, and many other terms similar in spirit if not necessarily exactly the same in meaning or a vision for implementation. In "The Historical Roots of Concurrent Engineering Fundamentals," Robert Smith shows that manufacturers were conscious of the need for bridging over 100 years ago.1 In many companies, a few skilled people, such as Henry Ford or Cyrus McCormick, held all the decisions in their minds and coordinated the intellectual effort of both design and manufacturing. By and large, these companies made all or nearly all of the items that went into their products.
As the 20th century advanced, products became more complex, companies became larger, and the ranks of capable suppliers grew. All of these processes led to the division of labor in both design and manufacturing, not only within companies but also along supply chains. New materials, new manufacturing processes, complex engineering calculations, and increasing customer expectations all have led to the creation of specialties in all aspects of product realization. As individuals have become more specialized, they have become more dependent on the knowledge of others. As a result, a shortage of individuals who know about multiple aspects of this process has developed. In many companies and industries, the process of creating a product is done linearly, passed from person to person with no backward or forward integration. Although this process may be successful if the product is simple or repeats past
designs and manufacturing methods, it can lead to problems on the factory floor, delays in product launch, higher costs, and dissatisfied customers.
In the last 30 years, information technology has become more and more important to the processes for product creation. Computers are essential in the design of parts, the calculation of stresses and strains, the estimation of costs, and the simulation of performance. Nevertheless, the overall process remains somewhat fragmented. More software tends to be developed for aspects of the process that have mathematical representations or cover one or two physical phenomena. These aspects include computer-aided design, finite element analysis of loads and deformations in solids and flows in liquids, animation of mechanical motions, simulations of operations on a factory floor, behavior of robots, and even motions and stresses on human operators. This approach has limitations when it is applied to products that are increasingly multifunctional and contain multiple technologies. Further, efficient manufacturing, including customizing and responding rapidly to customer orders, requires increasing integration between design and manufacturing.
The need is especially great in areas where product technology is advancing rapidly, such as national defense, where the commercial notion of competition is replaced by the notion of threat. It is well known that technology can give the warfighter a huge advantage, and staying ahead technologically is essential. Thus, development of defense systems is always on the cutting edge and must utilize every available tool to bring new systems to users quickly and affordably.
BENEFITS
Efforts to integrate design and manufacturing in both the commercial and national defense sectors could have profound impacts on productivity and economic growth. After languishing for nearly 15 years, multifactor productivity growth in U.S. manufacturing, which is a broad measure of the efficiency for all inputs including labor, materials, energy, and supplies as used in production, staged an impressive resurgence during most of the 1980s and especially after the early 1990s (see Figure 1-1).
There is accumulating evidence that the upsurge in productivity during the 1990s was due largely to the development and application of information technology.2 If successfully adopted, the changes identified in this report could prolong and perhaps even accelerate this turnaround in productivity growth. In the committee's opinion, integrating manufacturing simulation models promises to substantially improve the efficiency of the design process, reducing the time to deployment and most importantly overall system cost.
The additional capabilities made possible by adopting integrated manufacturing models could lead to the creation of new products and services, further expanding the nation's economic base and increasing international competitiveness. Adoption of integrated systems, along with the necessary technologies and incentives, will not only benefit our economy as a whole but also improve the efficiency and profitability of firms, the effectiveness of DoD programs and weapon systems, and the satisfaction of customers and users.
FUTURE VISION
A future with enhanced bridging of design and manufacturing must address four domains: technical capabilities, the organization of companies and work within companies, the cultural dimension, including incentives for people to work together, and the regulatory dimension that seeks standards for data exchange and other unifying aspects.
On a technical level, a basic need exists for a more thorough understanding of the complex interactions between design decisions and manufacturing options. This includes the need for a way to capture, quantify, and convey the needs of users of advanced products and systems. Second, the areas of developed information technology need to be integrated in a staged process that overcomes incompatibilities and will enable designers to expand the range of phenomena covered. More powerful computers may also be needed.
Organizationally, better definitions of the roles and responsibilities of individuals and groups are needed as the concepts of product and process are increasingly integrated. This is especially critical given the increasingly fragmented and international economic structure that has developed in the last decade. This will require revised management practices and educational agendas. Incentives may be needed to encourage investment in research and new work methods, training, processes, and facilities. Because there are currently no incentives for companies or governments to use one standard program or approach, both national and international cooperation will be needed to facilitate the improved interoperabiity of software and the integration of data created by different companies.
The committee has formulated its vision in terms of a coherent framework that describes an integral system for bridging design and manufacturing through both new and improved data management, modeling, and simulation. This framework assumes a central role for information technology in the form of virtual design and manufacturing. Virtual design and manufacturing constitute an engineering process that integrates computational modeling, simulation, and visualization to design, develop, and evaluate products with their manufacturing processes to meet customers' life-cycle needs.
The committee also recognizes the need to provide complementary improvements in the organization of companies and supply chains as well as changes in company culture, government and regulatory incentives, and the education of engineers and managers so that improved technologies will be both developed and implemented successfully.