Concurrent engineering
One of the strength points that make the company strongly competitive in the market is differentiation which means introducing a new product that is different from other competing products available. Introducing new product starts with initial planning followed by several technical and non-technical activities such as analyzing, implementing, testing, evaluation, and ends with product deployment. The company which intends to introduce new product is exposed to face several problems such as; the difficulty of implementation of the early design, communication between engineers working on different stages of the process, software compatibility, and ensuring the customer satisfaction of the new product in addition to the problem of the time to design and the time to redesign the product. All these problems can be addressed using a philosophy called Concurrent Engineering (CE).
What is concurrent engineering (CE)?
There are several ways in defining the concurrent engineering, one of them is used by Smith R. P., Barton R. R., Nowack C. A., and Zayas J. L. which indicates that concurrent engineering is a term that focuses on integrative product development aspects in the process of manufacturing a product which results in long-standing themes in product development practices by focusing on all elements of product life cycle simultaneously. From the definition we can conclude that concurrent engineering is one of the philosophes related to product design and development process. The opposite of concurrent engineering is traditional engineering in which most of the time is spent on designing and redesigning the product while shorter time is spent in defining the product.
What is the objective of concurrent engineering?
The ultimate purpose of concurrent engineering is approaching the customer satisfaction. This purpose is achieved by improving the interactive work of different disciplines affecting a product and minimizing product development timescales by maximizing the degree of overlap of design activities (source: James Scanlan).
How concurrent engineering achieves its objective?
There are several characteristics which can explain how concurrent engineering achieves its goal in satisfying the customer. One of these characteristics is that concurrent engineering assesses the conceptual design before moving to the physical design. This means that the design changes will be at the beginning stage of the product development or in other words it means assessing the design at its early stages rather that the subsequent stages as shown in figure1.
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Figure 1: the design changes as a function of time (source: Chapman, Bahill, and Wymore, 1992).
Another characteristic is that concurrent engineering controls the basic three parameters of manufacturing which are the quality, time, and cost. So, concurrent engineering finds a balance of all these three parameters together rather than focusing on one or two of them. This characteristic is very important because the efficient manufacturing system is the system which can produce products with high quality combined with the low cost and short time. So, concurrent engineering in this way can improve the efficiency of the manufacturing system.
Concurrent engineering fundamentals and barriers
There are four things that considered as the core of concurrent engineering; increased role of manufacturing process issues on product design decisions, formation of cross-functional teams, focus on customer requirements of the products to be made, and the competitive advantage of lead time (Chanan S. Syan, Unny Menon, 1994). All products have a need to incorporate constraints imposed by the manufacturing process in the product design. Depending on which manufacturing process is considered, these effects may be encoded into formal or computer-based rules, or else may be conveyed through individual experience and expertise. Addressing these design concerns early in the development process creates the opportunity to reduce manufacturing costs and improve product quality. Often the method of accomplishing the integration of design with other functions is through the use of cross-functional teams. These teams may include people with expertise in production, marketing, finance, service or other relevant areas, depending on the type of product. Another important functional barrier is the separation between the engineering designer and the customer. Under the same philosophy of removing the design-manufacturing barrier, the designer can become more responsive to customer desires and thereby create a more successful product. This is known as design-marketing integration. Lead time has proved to be a significant facet of modern competition. By lessening the lead-time the firm is able to rapidly respond to market trends or to incorporate new technologies. A lessened lead time creates a market advantage for those firms who are able to produce products rapidly. All of these ideas, which are fundamental to concurrent engineering, have been discussed in the literature for many years before the emergence of the concurrent engineering movement.
Product designs have existed for as long as mass production has existed. Early on, there arose a division of intellectual labor whereby the designer was responsible for producing the design and the manufacturer was responsible for making the actual product. Because of this division there is the opportunity for the product designer to work in ignorance of the manufacturer's constraints. The designer has been accused of 'throwing the design over the wall' which separates design from manufacturing. A design which is thrown over the proverbial wall is generally difficult and costly to produce, and does not necessarily conform to the desires of the market. This functional separation and its resulting adverse effect on the resulting product design may be repeated with other functions (such as marketing, maintenance or others). The remedy for this situation is to have the designer become more aware of other concerns within and without the organization in which s/he works. Engineering writers have long implored that these barriers be removed. There have been several distinct reasons for claiming that the role of manufacturing concerns in the design process should be increased. The most frequently repeated among these reasons are an increasing level of competition, the role of new manufacturing process, and the need to reduce development lead time. All of these justifications for pushing concurrent engineering ideas have deep historical antecedents.
One justification given for the need for increased cooperation in the product development process is an increased level of competition. There have been claims that the level of competition has increased 'recently' at times which we no longer consider recent. For example, a claim is made that the level of competition has increased since the beginning of the nineteenth century and modern firms can not afford to ignore design-manufacturing interaction issues. Similarly, another claim is that the high level of competition in the 1950's required that design and manufacturing personnel cooperate on new product development. Economic competition is now and has always been fierce. This is not a new effect.
As new production methods come into service it becomes important for knowledge about the new production processes to affect the resulting product design to take advantage of, and respond to the limitations of the new processes. Knowledge about these processes must be made available to the product designer. This knowledge is often resident in the production engineer. Therefore, the situation where new production processes are used will often be an important area for ensuring that design engineers work closely with production engineers. Among new manufacturing processes, the development of automatic assembly techniques has been frequently cited as requiring a higher level of integration between design and manufacturing. New manufacturing processes are being developed continuously. Each manufacturing process, when it is new, requires close cooperation between the designer and the manufacturing engineer.
One of the prime motivations for a concurrent engineering approach to product development is a desire to shorten the total time that it takes to bring a product to the marketplace. The notion that the length of the development cycle is an important competitive advantage and that addressing all aspects of the design problem simultaneously might lead to a shortened development cycle is a long-standing precept. In summary, the claimed reasons for the need of integration of economic competition, new production processes, and a shortening lead time are not new.
The question now; what are the tasks of product design and development which are needed to be done in order to reach the final product? figure2 below show the required iteration of the tasks which are market analysis, design, process planning, and finally manufacturing.
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Important elements in practicing concurrent engineering
One of the factors or elements that are needed to be considered in applying concurrent engineering is the cross-functional teams. This can be achieved when the project team members gain a better understanding of project priorities and process discipline, making risks and compromises visible for better control. The design team is composed of experts from engineering, production, marketing and any other functional area which has a vested interest in the development project. The team is formed to work on a specific project, and stays together throughout the development of the product. This approach seems more recent, as it has been discussed throughout the forties, fifties, and sixties as a viable mode of accomplishing complex development work.
Another element is the liaison personnel who are not members of any functional piece of an organization, but rather people who are capable and prepared to address issues which span functional organizational boundaries. Liaison Personnel have as their full-time job the coordination of the disparate functions. Under this approach, they become the primary modes of accomplishing information transfer between functional areas.
Job rotation is also one of the important elements in concurrent engineering. Job Rotation means to rotate personnel between functional categories. These personnel are assigned temporarily or permanently outside of their accustomed functional specialty that is a manufacturing engineer will work with design engineers or vice versa. Thus it is possible to integrate the various knowledge bases without making significant structural changes to the organization. Job rotation does seem to have useful integration benefits.
The previous three elements mentioned before belong to the organizational level. There are some other elements which are related to the methods of doing the product design and development tasks. These elements are product design methods and integrated computer analysis. There are several categories for product design methods; design for manufacturing (DFM), design for quality, design for cost, design for assembly (DFA), design for safety, design for reliability, design for X. Design for manufacturing seeks to minimize manufacturing information content of a product design to the fullest extent possible within constraints imposed by functionality and performance. It includes; minimizing the total number of parts, simplifying the design to ensure that the remaining parts are easy to fabricate, assemble, handle and service, and standardizing where possible to facilitate desirable produceability characteristics such as interchangeability, interoperability, simplified interfaces, effective consolidation of parts and function, availability of components and so forth. Design for quality can be implemented in the system design step by intentionally designing the product and process to be tolerant of variation. Design for cost is essential that industrial organizations have viable and responsive cost analysis and control systems. Effective analysis of product or project costs and the ability to implement cost control management includes management of the product or project cost, and this requires a knowledge and understanding of the cost elements and their sensitivity to various control parameters. Cost analysis forms the basis for cost control, and without accurate and timely cost data, effective cost control is impossible. The most accurate and timely cost data are useless unless coupled with an effective cost control mechanism. Design for assembly seeks to minimize cost of assembly within constraints imposed by other design requirements. DFA has been the starting point for development of a corporate DFM philosophy and the culture change that accompanies it. In design for safety the designer must develop the habit of constantly evaluating the design for safety, considering not only the design itself but the personnel involved in fabricating the product, using the procedure, and in maintaining and repairing the product or system as well as the end user or purchaser. Developing the manufacturing processes as well as the maintenance and operating procedures early during the design process will assist in revealing safety problems at a time when corrective action can be taken at minimum cost. In design for reliability the reliability of the system is considered which is defined as the probability that a system device or component will successfully perform for; a given range of operating conditions, a specific environmental condition, a prescribed economic survival time. Design for X helps to ensure that parts and products are correctly designed to be produced using a particular production process or method such as plastic injection molding or sheet metal stamping. The other element in product design methods is integrated computer analysis. This is based on the recognition that steps in the development of a manufactured product are interrelated and can be modeled effectively by using computers. This relationship comes about not only from the characteristics of the part being fabricated but also from the processes, specifications, instructions and data that define and direct each step in the manufacturing process.
Examples
Example1: The Aeronautical Systems Group at Lockheed Corporation recently developed and integrated metal-bending facility called Calfab. This mini-factory uses computer-aided layout and fabrication and has shortened the time it takes for design and manufacture of sheet metal parts from 52 days to 2 days - a 96 percent reduction. Metal used to travel 2500 ft. between various machines and now it travels only 150 ft.
There are few manufacturing firms left that have not targeted at least a 50 percent reduction in the time it takes to launch a new product from idea to production. Companies like Xerox have already accomplished this goal. Few organizations have pushed this concept to the point of having a corporate design strategy or a way of projecting the design and full-range planning of all their products five years into the future, but this is coming. It is the rare company that has an innovation strategy that includes decisions about the business and new products, risk, and production.
Good ideas that are novel have a unique motivating quality. People get excited about them and eventually there will be competition and disagreement about their origin. Nonetheless, most ideas -good or bad- are never acted upon either by individuals, groups, and, especially, enterprises.
Example2: In 1986, the General Electric Company (GE) marketed a new refrigerator. Their engineers were confident that their new compressor would help them leapfrog the Japanese; yet, in 1988 they declared a loss of $450 million. What went wrong?
The story began in 1981, when the market share and profits of the GE Appliance Division were falling. GE was using 1950's technology to make compressors. Each compressor took 65 minutes to make, whereas Italian and Japanese companies made theirs in 25 minutes, with lower labor rates.
The GE engineers said they could reduce the part count by one-third by replacing the reciprocating compressor with a rotary compressor, like the one used in their air conditioners since 1957. Furthermore, they said they could make it easier to machine by using powdered-metal instead of steel and cast iron for two parts, thereby cutting manufacturing costs. Although powdered-metal had failed in GE air conditioners a decade earlier, no one on the new design team had experience with this previous failure, and evidently, they felt no need for advice from people involved in a failed project. They also turn down advice from Japanese and American consultants with experience in designing rotary compressors.
Six hundred compressors were "life tested" by running them continuously for two months under temperatures and pressures that were supposed to simulate five years of actual use. Not a single compressor failed, and the good news was passed up the management ladder. During testing, technicians noticed that many of the motor windings were discolored from heat, bearing surfaces appeared worn, and the sealed lubricating oil seemed to be breaking down. This bad news was not passed up the management ladder!
GE offered a five year warranty on the refrigerators, but they could not wait five years before beginning full-scale manufacturing. Evaluating a five -year life span based on two months of testing is tricky, so the original test plan was to field-test some refrigerators for two years before full-scale manufacturing began. Pressure to stay on schedule reduced this test time to nine months.
By the end of 1986, GE had produced over one million new compressors. Everyone was ecstatic over the new refrigerators; however, in July of 1987 the first refrigerator failed. Quickly thereafter came an avalanche of failures, and the engineers could not fix the problems. In December of 1987, GE started buying foreign compressors for the refrigerators. Finally, in the summer of 1988 the engineers made their report. The two powdered-metalparts were wearing excessively, increasing friction, burning up the oil, and causing the compressors to fail. GE management decided to redesign the compressor without the powdered-metal parts, and in 1989 they voluntarily replaced over one million defective compressors.
The designers who specified powdered-metal made a mistake, but everyone makes mistakes. Systems engineering is supposed to reveal such problems early in the design cycle or at least in the testing phase.
Conclusion
Concurrent engineering is a process in which appropriate disciplines are committed to work interactively to conceive, approve, develop, and implement product programs that meet pre-determined objectives. Concurrent Engineering is the relatively recent term applied to the engineering design philosophy of cross-functional cooperation in order to create products which are better, cheaper, and more quickly brought to market. This new trend reunites technical and non technical disciplines such as engineering, marketing and accounting. Always focusing on satisfying the customer, these organizations must work together in defining the product.
The philosophy of concurrent engineering is important because it leads to successful product because it balances the three parameters of the product; quality, cost, and time. Since it reduces the number of design changes at the late age of the product, lets the design engineers work together with production engineers, and reduces the time required from design till mass production.
References
-Engineering Modeling and Design. Willian Luther Chapman, Terry Bahill, A. Wayne Wymore, CRC press 1992.
-Module SESA3002a; Aerospace Design, James Scanlan; School of Engineering Sciences.
-Concurrent Engineering In Product Design And Development. Moustapha.I, 2006.
-Concurrent Engineering; concepts, implementation, and practice. Chanan S. Syan, Unny Menon. Chapman & Hall, 1994.
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