Design for Time to Market

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CHAPTER

DESIGN FOR TIME TO MARKET

Nosa. F. O. Evbuomwan

1. INTRODUCTION

The success of any product is determined to a large extent by the customers

and users within the intended market place. This is more critical for

products that thrive mainly on `market pull’. Fashion and style products

traditionally are influenced by the speed at which they get to the market

place, but in today’s market, many engineering products are now also faced

with increasing fierce competition, based on the speed at which they get to

the market place. Maximising the paralleling of the various design and

other engineering activities, during product development, as well as aiming

to increase the speed to market and thus reducing the product development

cycle time in a modern manufacturing environment, represents a true

concurrent engineering imperative.

Several definitions have been given to Concurrent Engineering, the

prominent one being that given by Winner et al1, who define Concurrent

Engineering as a systematic approach to the integrated, concurrent design

of products and their related processes, including manufacture and support.

This approach is intended to cause developers, from the outset, to consider

all elements of the product life cycle from conception through disposal,

including quality, cost, schedule and user requirements. Concurrent

Engineering has been the subject of discussion in several research papers,

conferences and books2-10. It is rapidly gaining ground particularly in the

manufacturing industry, and more recently in the construction and

petrochemical sectors as a progressive approach for ensuring

competitiveness and survival in the market place. A number of issues

constitute the ethos of concurrent engineering. Prominent amongst these

are: (i) the need to improve and maintain the quality of a product, (ii) the

reduction of product development costs, (iii) the removal of barriers (walls)

between product development groups, (iv) responding proactively to

customers, (v) bringing downstream issues such as manufacturing,

production, operation, maintenance, testing, use, etc., which impinge on the

design process, upstream to the design stage, and (vi) maximising the

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paralleling of the various design and other engineering activities, during

product development as well as increasing the speed to market, thus

reducing the product development cycle time.

Time to market can generally be defined as the elapsed time between

product definition and product availability. The current wave and

emergence of new and improved products, extensions and expansions of

product lines, revisions and enhancements of products, creates additional

pressures on manufacturers to keep a steady stream or flow of new

products into the market place11. It is well established that any delays in

bringing a product to market, results in greater losses of profit. Hence

designing products for fast time to market, ensures the achievement of

optimum profitability10. A key influencing factor in achieving `Time to

Market’, is the design process, which has significant impacts on the

downstream functions of product development. Faulty, hurried or

inadequate product definition and design, usually results in design changes

in the form of engineering change orders (ECO’s), which are always very

costly in both time and money. Furthermore, the later these design changes

are implemented in the development cycle, the more costly the

implementation. Time to market is also dependent on the speed of

movement of design information across the company. This can be

enhanced by the use of computer networking technologies. Research by

Kusiak and Yang12 concluded that the implementation of concurrent

engineering, although may prolong the initial stages of design, does reduce

the overall design cycle (i.e. leads to shorter overall design cycle).

This chapter therefore will aim to address within the context of

concurrent engineering, the various issues which relate to designing for

time to market. It will begin by discussing the goals, objectives and the

need for designing for time to market. The benefits as well as the general

requirements for achieving time to market will also be elucidated. Design

Function Deployment (DFD) a concurrent engineering design system, will

then be introduced as a platform for designing for time to market. Further

discussions will also cover tools needed for designing for time to market,

as well as their management during product development.

2. GOALS, OBJECTIVES AND NEED FOR DESIGN FOR

TIME TO MARKET

This section will focus on key aspects relating to necessary goals and

objectives to be considered in designing for `Time to Market’. The section

will also address the rationale for design for Time to Market, and why it is

necessary for companies to adopt this approach to product development.

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2.1 Goals and Objectives

The goals and objectives of designing for time to market are closely

aligned to concurrent engineering goals and include inter-alia the following 13: (i) the need to effectively compete in a global market place, (ii) the

necessity of reducing cycle time and cost, (iii) the need to improve quality

of product and to develop defect free products and services, (iv) to enable

flexibility, manufacturability and reliability both of the design process and

the product, (v) to increase product customisation and the number of

product options, (vi) to take advantage of new manufacturing strategies and

(vii) to achieve cost efficient design flexibility.

2.2 Need

A key reason to adopt the approach of designing for time to market, is due

to the fact that delayed introduction of new products to the market place,

reduces the lifetime profit potential of the products. The research by

McKinsey and Co. has shown that a product that is six months late to the

market will miss out on one third of the potential profit over the product’s

lifetime 11, 14, 15. Such delay in product introduction to market also makes it

harder for manufacturers to enter the market against an established

competitor. Companies constantly face the challenge to cope with

international competition, as well as competing on the basis of fast time to

market. For companies to succeed in their endeavour to remain

competitive, they need to adopt a design for fast time to market strategy.

3 BENEFITS OF DESIGN FOR TIME TO MARKET

Justification for adopting a design for fast time to market strategy, relates

to the financial benefits that can accrue to any particular company that

embarks on such endeavour. Such benefits include the following 16, 17: (i)

the extension of the period of product sales, (ii) the possibility of gaining

more customers and an increase in market share, (iii) the possibility of

higher profit margins and the enjoyment of more pricing freedom, (iv) the

exploitation of technical opportunities by synchronising product

development with latest technology, (v) the possibility of improving

company culture, as design for time to market becomes a company wide

attitude, (vi) the possibility of gaining an early access to the market, which

can give freedom to set higher prices and capture larger markets, (vii) the

enablement of using new technologies and fresh market information, (viii)

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the volume of sales can be built up over the entire life cycle of the product

and (ix) unforseen problems can be reduced and product predictability can

be improved.

4 GENERAL REQUIREMENTS FOR DESIGN FOR TIME TO

MARKET

To ensure success in designing for time to market, certain general

requirements need to be addressed. These represent strategic initiatives to

be implemented within an enterprise and are discussed under the broad

headings of (a) Top Management Commitment, (b) Organisational

Integration, (c) Use of Vendors and Suppliers, (d) Use of Computers and

Technology and (e) Market Strategies.

4.1. Top Management Commitment

For the successful achievement of `Time to Market’, it is needful for the

top management in an enterprise to provide an environment which

encourages faster new product introduction. They should provide computer

based tools and systems as well as a vision of the future and a time to

market goal, to support the adoption of flexible and robust development

methodologies. It should also be the prerogative of top management to

ensure clear communication within project groups and organisational focus

on set goals and tasks.

4.2. Organisational Integration

Within the overall organisation, there should be clear, open, timely and free

flowing communications flourishing amongst the various divisions and

disciplines responsible for product development. These product

development teams must ensure clear understanding of customer

expectations and continuous customer contacts18. Close collaboration

should be established between the company’s development, production and

commercial functions. The company’s modus operandi should be improved

by the formation of multi-functional teams to facilitate the management of

an integrated design and manufacturing process. It is also important that

top management, treats each discipline in the organisation with equal

importance. Ensuring `Time to Market’ also requires the improvement of

two way and frequent communication amongst the development teams. All

life cycle aspects impinging on the product development process should of

necessity be integrated, as product development teams are constructed.

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This will also involve integrating downstream factors into upstream

problem solving19. Furthermore, an organisational environment should be

created and fostered, where change and innovation occur naturally, with the

aim to minimize the amount of work and rework to be done in developing

a product.

4.3. Use of Vendors and Suppliers

It is imperative that in order to achieve early `Time to Market’, vendors and

suppliers, should be included early in the product development process. A

systematic view of the innovation/development process should be adopted,

involving all parties in the development process. It is expected that this

team, will use common, consistent, accurate and complete design data.

4.4. Use of Computers and Technology

In a modern manufacturing enterprise, the process of integrating the

organisation, cannot be done without the aid of computers. There is hence a

need for the integration of computerised information systems within such

companies, to support the early `Time to Market’ initiative. Such

computerised systems should inter-alia, provide and support open

communication amongst the various divisions within the organisation.

They should enable : (1) early sharing of information, (2) automation

(computerisation) of the design process and (3) the adoption of

manufacturing strategies aimed at reducing manufacturing lead time20.

Another requirement of the system is the support of advanced technologies,

which enable information flow, provide information about new

technologies and developments, as well as supporting tools to improve

product development and speed of the design department. Such new

technologies should be adopted to give employees the most current proven

tools to do their jobs.

4.5. Market Strategies

The successful achievement of designing for `Time to Market’

imperatively requires an understanding and knowledge of the customers

and users within the specific or general market outlets for the proposed

product. The emerging windows of opportunity, risks and opportunities as

well as the necessary trade-offs to be made between time, quality and cost,

need to be clearly understood. In this regard, it is incumbent on a

manufacturing company to: (i) carry out adequate market surveys and

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strategic explorations, (ii) clearly define key attributes of competitive

strategy, (iii) when necessary, focus on a series of incremental

improvements in the product rather than new designs and (iv) make

available market information about new products to designers/engineers.

5 FUNDAMENTAL ISSUES AND FACTORS AFFECTING


Depending on the particular type of product, the product planning strategy

adopted and the particular approach to be utilised for designing for time to

market, certain issues which are fundamental, need to be addressed. These

are discussed below under the following headings :

(i) Modularisation during conceptual design, (ii) Overlapping and

Resequencing of Activities, (iii) Integration of Product Development

Activities, (iv) Product Classification, and (v) Strategic Product Planning.

This section concludes with a summary of general issues and factors

affecting design for `Time to Market’ which should be taken into account

within an enterprise in seeking to achieve the objective of early time to

market.

5.1. Modularisation During Conceptual Design

The conceptual design of a product, to a large extent can decide how fast a

product gets to the market. Key issues to be addressed, include : (i) what

functions are to be provided by the product and (ii) the interrelationships

between the functions and deployment of the functions to different parts of

the product. Making the correct decisions at the conceptual design stage is

critical to shortening the design cycle. A key decision to be made during

conceptual design in support of time to market, is the modularisation of the

design of the product. This can involve the division of the product into

modules (subsystems, components or parts), based on the modularisation

(decompositions) of the desired functions of the product. Each of the

modules and submodules, can then be developed concurrently, thus

permitting overlapping of activities and hence reducing the length of the

design process, while preserving coupling among design activities. The use

of appropriate module construction methods, will promote the progress of

parallel design teams working on each module. Standard components can

be used in the product, and thus concentrating efforts on the most

important product characteristics. The above modularisation process, can

also enable quick update of designs. In modularising designs, care should

be taken to ensure that, design concepts are developed to be insensitive to

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minor changes in the interfaces between modules. Features of interaction

across and between modules that have an effect on product development

speed, must be resolved.

5.2. Overlapping and Resequencing of Activities

The product development process is characterised by the performance of

many design activities. During product development, it is needful for these

activities (tasks) to be divided and their interdependencies, established. In

most companies, these activities tend to be performed in a sequential

manner, with the engineers being oblivious to the inherent coupling

between the activities. The result of this, is costly engineering changes. In

sequential design, downstream activities start only after receiving finalised

information from their preceding activity. In order to accelerate the product

development process within the context of concurrent engineering and

designing for time to market, the coupling between activities, need to be

removed. This is to enable the performance of the activities in a parallel

(simultaneous) manner. In this case, each activity can proceed without

waiting for any information from a preceding activity. This requires

flexibility and focus from all participants in product development. In

instances where, coupling between activities cannot be completely

removed, the approach plausible, involves the overlap of the activities,

through frequent exchange of preliminary design information21. Such

overlapping process enables downstream activities to begin early by using

the preliminary design information from preceding activities. Overlapping

activities of the different phases of product development enhances fast

cycle development of new products22.

5.3. Integration of Product Development Activities

A key issue in achieving fast time to market, involves the integration of all

activities impinging on the product development process, and adopting a

co-operative product development approach23. The integration should be

based around people, information, computing technologies and tools. The

integration process should therefore support extra input at the early stages

of the product development process, particularly from downstream issues

(manufacturing, testing, service, etc.).

5.4 Product Classification

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The variation between different products primarily arises as a result of the

different disciplines (mechanical, electronic, civil, chemical, etc.) from

which they are developed. Within each discipline however, product

variation can also be attributed to other factors such as : the intended

market segment, knowledge available, the integration of disciplines (e.g. as

in mechatronic design), the design process and manufacturing capabilities.

The nature of bounding constraints, customer demands and competition in

the market place, can also result in various product classifications. Such

product classifications that have emerged within the recent past are

discussed below24 - 26.

5.4.1. Static Product Designs. These are products whose market share is

generally undiminishing and little or no changes are being demanded in the

product. They are usually based on well known design concepts, and are

hence considered to be conceptually static products. For such products,

releasing them early to the market will not necessarily provide a

competitive advantage.

5.4.2. Dynamic Product Designs. These products tend to have a limited

life before the next generation supercedes it. In this case, developments are

focussed on the product, involving the development of new, radical and

alternative designs. Products belonging to this class, are generally

considered to be conceptually dynamic. In looking at the dynamic - static

spectrum of products, Clausing25 highlights the following types of products

sandwiched between the two extremes :

Genesis Product - This is an original product that has no previously related

product, and usually leads to the evolution of diverse families of products.

Radical Product - This is a product which although may at the higher

(concept) level of abstraction exhibit similarities to previous designs, but is

radically different in the final designs of the subsystems.

New Product - This is usually less than a radical product, and involves the

use of a new or an alternative technology in the development of an already

existing product.

Clean Sheet (Generational) Product - A clean sheet generational product is

usually characterised by a major step forward, and the design process

commences from a clean sheet of drawing paper, with little reference or

relationship to prior designs. The genesis, radical and new products are by

definition clean sheet designs.

Market-Segment Entry (New) Product - A market-segment entry product

moves a company for the first time into a new market segment, following

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an earlier new (or radical) product. This is associated with the staggered

window of opportunity case discussed below, in the next subsection.

Market- Segment Entry (Generational) Product - This form of product is a

new product in a market segment following after a previous product in the

same market segment.

Associated Product - This is the type of product that changes some

technologies to provide a different capability, resulting in an entry into a

somewhat different market segment. An example is the case of laser

printers, which are based on xerographic copiers.

Variant Product - Variant products are those which are based on relatively

small changes on the base product. They usually include feature

enrichment or removal, dimensional magnification or downsizing, and

cost/performance upgrades.

Customised Product - Customisation of products extends over a range from

adding brand names to fairly major changes on a product for specific

customers. Customised products tend to have a limited role in the general

subject of product development.

5.4.3. Overconstrained Products. These tend to be products which exist

in the high technology markets. Here, the design process evolves around

analysing alternative design proposals until the correct (or most acceptable)

solution is found. Overconstrained products are usually subjected to several

constraints of function, materials, manufacturing processes, some of which

might be conflicting, and the product undergoes several analysis and trade-

offs. In this case, major changes in the product concept rarely occurs.

5.4.4. Underconstrained Product Designs (Ideas Centred). In the case

of underconstrained designs, the design activity is centred around bringing

products into the market to satisfy market demands. There are usually not

very many constraints, and the designer has ample room for innovation.

The focus here is usually on the product concept, and materials and

techniques are chosen to satisfy the required function and recognisable

market style. Most industrial designs fall into this category, and

development is on aesthetics, ergonomics and functionality.

5.4.5 Underconstrained Product Designs (Skill Based). This form of

designs focus on the manufacturing aspects of product development.

Efforts are usually concentrated on the capabilities and skills available in a

company.

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5.4.6 Complex Products. Complexity in design and product

development can be examined from a number of viewpoints. If a complex

product is considered from the viewpoint of a complex system, then it can

be described as a product exhibiting complexity in shape and size, having

many interacting elements (subsystems, components and parts), which can

exist in different and perhaps changing states and which influence each

other. The time taken to design and develop the many constituent

interacting elements can also be considered to be contributory to a

product’s complexity.

5.4.7 Simple Products. A simple product can be described as one

having a simple shape and/or size, few interacting or possibly non-

interacting elements (subsystems, components and parts), which generally

exist in similar and perhaps non-changing states, with little or no influence

on each other, and which can be designed and developed within a relatively

short time.

The above classification can be schematically represented in the form of a

cube as shown in Figure 1. This cube comprises eight smaller cubes

representing different scenarios of product classification. They are : Cube 1

- Static-Simple-Underconstrained (SSU), Cube 2 - Static-Complex-

Underconstrained (SCU), Cube 3 - Dynamic-Simple-Underconstrained

(DSU), Cube 4 - Dynamic-Complex-Underconstrained (DCU), Cube 5 -

Static-Simple-Overconstrained (SSO), Cube 6 - Static-Complex-

Overconstrained (SCO), Cube 7 - Dynamic-Simple-Overconstrained

(DSO) and Cube 8 - Dynamic-Complex-Overconstrained (DCO)

FIGURE 1. The Three Dimensional Product Classification Matrix

1

2

5 7

8

3

4

6

SIMPLE

COMPLEX

STATIC DYNAMIC

UNDER-CONSTRAINED

OVER-CONSTRAINED

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5.5 Strategic Product Planning

In designing for `time to market’, an issue that needs to be addressed is

how a company can go about strategically planning its products for the

various market segments and outlets. This issue of strategic product

planning will be examined primarily from two dimensions of what can be

referred to as Product Design Input and Product Design Output. It will also

be examined from the viewpoint of how the interaction of product

complexity and product uncertainty affects the need for a company to

proactively respond to the market. The discussions in this subsection draws

upon the work of Rajczi27.

Based on the first two dimensions, the step towards strategic product

planning can be explicated using a `Global Product Design Grid’. This grid

in the form of four quadrants can be used to represent the Product Design

Input and Product Design Output, as shown in Figure 2a.

Product Design Input represents how many markets a company gathers

relevant input before embarking on the design of its initial products. Here

such inputs can range from customer information gathered from all

possible markets to single market or specific subsets of these markets.

Product Design Output on the other hand, represents the markets that the

initial product will actually be designed for. This can also range from the

development of a single product for all markets to different products

developed for each market or specific subset of the company’s markets.

FIGURE 2a. Global Product Design Grid

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The interaction between the two axis of the matrix and the possible

location and movements by companies within any of the quadrants, is

driven principally by two forces (factors), namely : Opportunity Risk and

Right Product Risk. Opportunity Risk refers to the situation where a

window of opportunity exists, whereby a company must respond to a new

or changing market within a certain period of time, or risk losing the

opportunity in that market. If the windows of opportunity are small, then

we have a high risk situation, whereas if the window of opportunity is

large, we have a low risk situation. In situations where there are small

windows of opportunity (high risk), companies tend to be forced to choose

product strategies whereby only a few specific markets are polled for input.

Furthermore, the alignment of small windows between markets also affect

product strategy. Two forms of alignments are discussed here, that is

Stacked Windows and Staggered Windows.

For Stacked windows (i.e. windows which are open for the same or

similar periods of time), companies would need to choose a strategy based

on Quadrant 2 (Figure 2b), while for Staggered windows(i.e. windows

which are open at different periods of time), a company should choose a

strategy based on Quadrant 3 (Figure 2b). In this case, initial products can

be sold to few specific markets which they are designed for. Subsequently,

the initial product can be taken to other markets as the windows open. This

tend to create some form of flexibility for a company, as time is made

available for it to design specific products for specific markets.

FIGURE 2b. Opportunity Risk Matrix

In the case of Right Product Risk, this means the risk taken by a

company by not providing the exact product each market wants. High right

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product risk relates to situations where (i) products which require

enormous development costs are being developed and (ii) a product is

introduced in to the market shortly after a previous product's failure. Low

right product risk on the other hand, relates to situations where a

company's products is able to be redesigned after its initial design, with no

major negative impact to the company's reputation or the product.

Designing the right product for a global market requires that a company

gather all relevant data needed to design a product for those markets. When

a company is faced with High right product risk, it tends to be forced to

choose a product design strategy that gathers all market information before

the initial design is carried out. Thus leading to the choice of strategies in

Quadrants 1 and 4 (Figure 2c).

The nature of the `Homogeneity’ of markets also affect a company's

choice of product strategy, in any of the four quadrants. For markets whose

needs (market's tastes, wants, regulatory standards, etc.) are Homogeneous,

a single product might meet the criteria for all of the markets. Here the

tendency is for a company to move towards Quadrant 1 (Figure 2c) -

development of generic products for all markets. For markets whose needs

(market's tastes, wants, regulatory standards, etc.) are Heterogeneous, there

is need to design multiple products for specific subsets of the markets. The

tendency here is for a company to move towards Quadrant 4 (Figure 2c) -

development of several market specific products.

FIGURE 2c. Right Product Risk Matrix

Depending on the adopted strategy within any of the quadrants, a

company must of necessity make certain trade-offs. These trade-offs are

generally based on three factors, namely : Complexity, Time and Cost.

Complexity can be examined from two aspects, that is, Design Complexity

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and Co-ordination Complexity. In general, the choice of a product strategy

affects design complexity. When market inputs are obtained from many

markets, this means more design complexity. Hence strategies based on

Quadrants 1 and 4, tend to result in higher design complexity (Figures 2d

& 2e). In this case, the only options available, is for the company to (i) look

for efficiencies in design (e.g. high or fast performance) and (ii) carry out

modular designs of the complex products. The co-ordination complexity of

a product design's maintenance and evolution increases with the number of

products designed. Hence the adoption of strategies based on Quadrants 3

and 4, results in higher co-ordination complexity.

In the case of Time, the trade-off borders on time required to

introduce a product to all markets vis-à-vis that required to introduce a

product to a single or specific subsets of markets. If therefore there is need

to introduce products in key markets quickly, then a company can choose

strategies based on Quadrant 2 or 3 (see Figures 2d & 2e). This minimizes

the time spent introducing the first product to the first market, and less time

is spent upfront in the early stages of product development. More

engineering changes, however occur. On the other hand, if the need is to

introduce a product in all markets as quickly as possible, then choosing a

strategy in Quadrant 1 or 4 (see Figures 2d & 2e), seems to be more

appropriate. In this case, more time is spent upfront in the early stages of

product development, the result of which is lesser engineering changes.

Cost principally relates to the amount of work done as well as time

spent upfront in the early stages of product development. Choosing a

product design strategy in Quadrant 2 or 3, will minimize short term costs

by not polling all markets or developing a complex product design. Here,

cost to first market is reduced. Conversely, polling all markets will result in

high initial costs.

Summarily, factors which can be considered to affect product

development speed and early time to market, include the following : (1)

Market Input (customer/user survey), (2) Market Output (Product Outlet),

(3) Product Classification (Type, Nature, etc.), (4) Product Complexity, (5)

Product Uncertainty (window of opportunity, performance and customer

satisfaction), (6) The Design and Development Process,

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FIGURE 2d. Advantages of Trade-offs

FIGURE 2e. Disadvantages of Trade-offs

(7) Downstream Processes (Manufacturing, Assembly, Testing,

Installation, etc.), (8) Ease and Speed of Manufacture and Assembly, (9)

Degree of Reliability before committal to Market, (10) Market Opportunity

(Low and High Risk), (11) Product Life Cycle and (12) Design Life Cycle.


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6. DESIGN FUNCTION DEPLOYMENT - A CONCURRENT

ENGINEERING DESIGN SYSTEM

The development of Design Function Deployment (DFD) was driven by

the need for a design system that will enable the design and manufacture of

not only high quality and performance products, but those which are well

suited for their intended purpose, affordable and satisfactory to the

customer. The research involved in this development, benefited from

research into Quality Function Deployment (QFD)28-31, Design

Philosophies, Models, Methods and Systems32-33, and Concurrent

Engineering34-38.

Design Function Deployment, DFD24, 39-40 has been developed as a

comprehensive design system, to incorporate the features of a prescriptive

design model, and associated design methods for the integration of

manufacturing, use and other downstream issues into design, and thus

enabling a concurrent engineering approach to product, systems or process

development. It uses the fundamental concepts of QFD, to enable the

establishment, focussing and satisfaction of customer requirements

throughout the product development process.

The goals of DFD inter-alia, include the following : (1) to recognize

the importance of customer requirements within a specified market, (2) to

ensure the change from the `over the wall’ approach to team approach in

design and product development, (3) to provide a platform for concurrent

engineering, (4) to generate the design solution space, (5) to facilitate

design retrieval (aka case-based reasoning and design) of previous design

solutions, (6) to maximize the knowledge about performance of product at

the design stage, (7) to minimize or eliminate downstream engineering

changes, (8) to establish robustness of design, (9) to utilize new materials

and technologies and (10) to ensure quality through design.

The design model of DFD as shown in Figure 3 proceeds through

five stages of (i) Establishment of customer requirements, and

determination of design specifications and constraints, (ii) Development of

conceptual solutions called `Architectures', (iii) Establishment of viable

variant solutions for each plausible architecture, called `Layouts', (iv)

Establishment of viable materials and corresponding manufacturing

processes for each viable layout and (v) Establishment of production plans

for each viable layout. The system is being implemented in a three layer

framework, as shown in Figure 3.

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FIGURE 3. The Structure of the Design Function Deployment System

(Adapted from24 )

The first layer represents the design process model described above,

the second layer represents the several design methods, tools and

techniques employed as the design progresses from stages 1 to 5, while the

third layer contain numerous knowledge bases and databases, which can

act as repositories for corporate knowledge, historical design data, proven

technologies as well as for generic materials and manufacturing processes.

6.1. The Design Matrix of Design Function Deployment

The design matrix in DFD, is examined from a three dimensional

viewpoint. The first dimension (z-axis) is referred to here as the

morphology of the

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design process, and it represents the five stages shown in level 1 of the

DFD structure, that is, the minimum prescribed path to be followed during

the design process. The second dimension (y-axis) is referred to as the

anatomy of the design process within DFD, and this represents the design

activities implicitly performed within each of the five stages of DFD. The

level 2 of the DFD Structure (Figure 3), contains design modules

(methods) which are used in performing the above activities within each of

the five stages of DFD. These modules are key to the DFD system and thus

represent the third dimension (x-axis) of the DFD design matrix. The three

dimensional matrix is shown in Figure 4. It shows the global view of the

design matrix within DFD, and it explicates the interactions of the three

dimensions. It should be noted that, it is only the morphological dimension

of the design process (i.e. DFD design stages), that represents a

chronological ordering of distinct steps and that the other two dimensions

do not represent any chronological ordering of distinct steps. There would

hence be continuous feedback, iteration and revision in performing any of

the design activities while using any of the design modules (methods or

tools). The matrix can be used to identify the activities that need to be

performed at any of the DFD design stages as well as the accompanying

tools that can be used for any of the activities, depending on the nature and

type of product or designs.

6.2. Design Function Deployment as a Concurrent Engineering

Design System

This section discusses Design Function Deployment (DFD) as a concurrent

engineering design system, within the context of its satisfaction of the main

goals and general requirements of concurrent engineering. The DFD design

system has been developed to support product development teams in

achieving early time to market, by enabling the integration of all life cycle

and functional issues under one umbrella. The DFD system at level 1

provides a structured format for carrying out the design process in a

planned and controlled way. This ensures that all necessary information

generated, analysis performed, evaluations done and decisions made, are

recorded and documented accordingly. The first stage of the design process

in level 1 ensures that elicited requirements (customer, user,

manufacturing, finance, marketing, etc.) are all considered in an integrated

and concurrent manner, before translation into design requirements.

19

FIGURE 4 The Three Dimensional Design Matrix

Level 2 of the DFD system contains many design modules (methods and

techniques) which can be used in a parallel manner, as the design activity

proceeds from conceptual to detailed design stages. These modules in their

use, ensure that design concepts are not only functional, but can be

manufactured, assembled, sold and used to the satisfaction of customers.

The third level of the DFD system contains databases and rulebases, some

of which are associated with the level 2 modules. These modules store

various design knowledge and information in the form of design rules,

materials and manufacturing data and previous design information that can

be retrieved and used for new designs. The databases and rulebases will

ensure concurrent access to both past and present design information by all

interest groups involved in the product development process. This will help

to remove unnecessary interfaces between the groups, and hence reducing

delays in the product development process. The link of the level 3 modules

with levels 1 and 2 in the DFD structure, also helps in the implementation

of concurrent engineering, by the integration of conceptual design,

20

geometric modelling, materials and manufacturing process selection, as

well as permitting the increase of product performance knowledge in the

early stages of the design process, when costs are committed.

7. DESIGN FOR TIME TO MARKET WITHIN DESIGN

FUNCTION DEPLOYMENT

The aim of this subsection, is to enunciate a rational approach for

paralleling the design process within the taxonomy of the design stages of

Design Function Deployment. The benefits of this approach, in terms of

separating the overall design into modular groups and activities, managing

the complexity and interactions between the separate design tasks and

subsequent reduction of the design cycle will be discussed.

7.1. Review of Design and Project Management Techniques

The adoption of the concurrent engineering approach in product

development, implies that engineers, designers and product development

managers, have to cope with a larger amount of design data and

information. The scenario where the designers not only uses engineering

information, but additional information from other disciplines involved in

the product development process, leads to further complexity of the design

process. Engineers and designers in this present climate, therefore need to

adopt techniques for planning, organising and monitoring the large and

complex network of design tasks arising in the product development

process.

Over the years, several techniques have evolved for managing

complex and large projects as well as the design process. Such techniques

include : Directed Graphs (DG) 41, 42, Project Evaluation and Review

Technique/Critical Path Method (PERT/CPM) 43, 44, Structured Analysis

and Design Technique (SADT) 45, 46 and Design Structure Matrix (DSM).

The above three networking techniques (Directed Graphs, PERT/CPM and

SADT) suffer from size limitations and an inability to explicitly represent

circuits (coupling) of the design tasks. They are usually based on one way

progression along paths, with no feedback or iteration and no feedforward

of information part-way through task 41, 44. They tend to be used primarily

or documenting design practices and do not handle interactions that occur

within design tasks.

21

7.2. Design Structure Matrix (DSM)

The philosophy of the Design Structure Matrix (DSM) technique is that the

design project can be divided into individual tasks, and the relationships

and interactions among the tasks analysed to identify the underlying

structure of the project. There is some belief that studying relationships

between individual tasks can improve the overall design process, as well as

being an effective way of analysing alternative design strategies 47. DSM

with the aid of a graphical representation (matrix) uses the structure of

design information flow to guide the decomposition of the design activity.

In this matrix, the links and relations between the tasks are mapped out in

such a way that makes their interdependence explicit.

The design activity which consists of for instance m tasks, can be

represented as an m x m matrix. Each of the tasks are labelled along the

side of the matrix as row headings and across the top of the matrix as

column headings, in an identical manner. The matrix element aij is non-

zero if node i provides information to node j. A typical matrix is shown in

Figure 5a. Interpreting the task ordering as a time sequence helps to make

the timing of information flow explicit. The marked elements within each

row of the matrix identify the other tasks that must contribute information

for proper completion of the design.

FIGURE 5a. A Typical Design Structure matrix

In the matrix, marks below the diagonal represent information

transferred to later tasks (i.e. task A must be completed before task C);

while marks above the diagonal depict information which are fed to earlier

tasks (i.e. task G must be performed before task B). The primary goal of

design structure management is to find a sequence of these design tasks

which allows this matrix to become lower triangular.

22

Once the design process has been established into a design structure

matrix, the analysis proceeds in two separate stages, known as Partitioning

and Tearing 41, 44, 48. The process of partitioning aims at resequencing the

design tasks, in order to maximise the availability of information required

at each stage of the design process. Partitioning helps to identify tasks

which are coupled in a loop, and then clusters them as blocks on the

diagonal of the design structure matrix (Figure 5b). The strategies of the

partitioning algorithm include: scheduling independent design tasks as

early as possible and then simultaneously identifying tasks which are

coupled for further analysis. Once partitioning has placed the design

structure in a block-triangular form, the tearing analysis then begins. The

goal of tearing is to resequence within the groups (blocks) of coupled tasks

to find an initial ordering to start the iteration. The algorithms employed in

tearing includes tearing with shunt diagrams and tearing with heuristics.

This form of matrix discussed above, represents what is known as the

activity-activity incidence matrix.

FIGURE 5b. The Partitioned Design Structure Matrix

Other forms of incidence matrices have also been discussed by 49, 50.

These include the module-activity incidence matrix and the procedure

(formula)-parameter (variable) incidence matrix. In these two cases, the

analysis of the matrix, involves the use of suitable clustering algorithms 51,

52. Decomposition of the design process and using the algorithms described

above, has been considered to lead to the following advantages 50: (i)

separation of the overall design task into groups design tasks and/or groups

of modules and activities, (ii) potential activities that can be performed

23

concurrently are detected, (iii) the complexity of managing the design task

is reduced and (iv) the design cycle time is reduced.

7.3 Concurrent Design Within Design Function Deployment

The process of bringing design influencing downstream issues early

upstream to the design stage, as part of fulfilling the ethos of concurrent

engineering, does lead to an increase in the activities to be performed in the

product development process. This factor coupled with the basic idea of

shortening the product development cycle time, lends weight to the need to

manage the design process and the associated interactions and

complexities, more effectively. In Design Function Deployment, the

process of concurrent (parallel) design, is considered from two main

viewpoints, which are :(i) Concurrent design associated with the design

process (CDDP) though stages 1 to 5 and (ii) Concurrent design

associated with the design artifact (CDDA).

Considering the first case, that is, CDDP, the flow through the five

stages of DFD, as shown in Figure 6, represent the minimum prescribed

path (critical path) to be followed in the design process, and is generally

not subject to any form of concurrency. However, at each of the stages,

several design activities are performed, with some of them somewhat

repeated down the later stages, and in other situations somewhat

overlapping. It is these activities that can be explored for possible

concurrency, and to speed up the design process within each of the stages.

Tables 1 to 3 shows typical activities for each of the five stages of the DFD

design model.

Some of these activities (or design tasks) which take place in each of

the DFD stages, would be inter-disciplinary, relating to for instance

(marketing, design, manufacturing, finance, testing, etc.), while others will

be intra-disciplinary (stress analysis, geometric modelling, feature-based

design, thermal analysis, etc. - all within for instance the design group).

The above implies that the larger inter-disciplinary team would be involved

in the inter-disciplinary activities, while the smaller design team would be

responsible for the intra-disciplinary activities. Irrespective of whether

these activities are inter- or intra-disciplinary, it is needful to decompose all

the activities within each DFD stage and then to establish those that can be

done in parallel and those to be carried out serially to precede other

activities.

24

FIGURE 6. The Flow of the Design Process in Design Function

Deployment

In this concurrent design case, the applicable form of incidence matrix is

the activity-activity matrix, which can be employed at each of the DFD

stages. With this form of matrix, the triangularisation algorithm

(Partitioning and Tearing) can then be used to decompose the activities into

groups of activities, thus simplifying the entire design process and these

activities can then be sequenced in such a way as to speed up the product

development time. This results in the overlapping situation that occurs

between the inter- and intra-disciplinary activities as they are being

performed, with activities belonging to either of them being performed in

parallel or in series.

25

TABLE 1. Design Activities in Stages 1 and 2 of DFD

Stage 1 Stage 2 1. Elicit Requirements

2. Analyse Requirements

3. Categorise Requirements

4. Prepare Quality Plan

5. Derive Design Functions

6. Analyse & Group Design Functions

7. Set Target Values for Design

Functions

8. Complete Correlation Matrix

9. Complete Relationship Matrix

10. Rate Design Functions

1. Establish subsystems from stage 1

Design Functions

2. Generate and Synthesise concepts

(Architectures)

3. Derive Design Functions


5. Set Target Values for Design Functions




9. Explore Materials and Manufacturing

Processes

10. Evaluate each Architecture

11. Select viable Architectures

TABLE 2. Design Activities in Stages 3 and 4 of DFD

Stage 3 Stage 4 1. Generate Layouts for each

Architecture

2. Derive Design Functions for each

part of Layout


4. Set Target Values for Design

Functions




8. Materials Selection

9. Evaluate & Select Viable Layouts

10. Create Solid Models of Layouts

11. Finite Element Analysis/Mechanism

Analysis

12. FMEA/FTA Analysis

13. Robust Engineering Design

14. Evaluate against DF`Xs'

15. Select Optimal Layout

1. Establish Viable Materials and

Manufacturing Process

2. Derive Manufacturing Design Functions

for each part of Layout.


4. Set Target Values for Design Functions




8. Establish Critical Manufacturing

Processes

9. Manufacturing Process Planning

10. Simulate Manufacturing Process Plans

11. Assembly Planning

12. Rapid Prototyping

13. Evaluate against DFM, DFA and

DFDisassembly

14. Materials Resource Planning

26

TABLE 3. Design Activities in Stage 5 of DFD

Stage 5 1. Job Scheduling

2. Line Balancing

3. Batch Size Determination

4. Routing Procedures

5. Capacity Analysis

6. Planning for Inspection

7. Simulation of Production Plans

8. Layout, Machine and Tooling Procedures

It is worth noting that the number and type of activities that would be

carried out in parallel or in series would depend not only on the

engineering domain of the design, but also on the nature, type or class of

the product. In the second case, that is, CDDA, the performance of

concurrent design depends to a large extent on the type and nature of the

product. Products can generally be classified as static (fixed concept) or

dynamic (short life cycle and requires new concepts), as well as

overconstrained or underconstrained (could be ideas or skills based). For

this case, four forms of concurrent design are considered. The first form

involves the design of competing alternative architectures (at stage 2 of

DFD) in parallel, as shown in Figure 7 and the second form involves the

design of competing alternative layouts (at stage 3 of DFD) in parallel.

The third form of concurrent design relates to designing in parallel

the individual subsystems that constitute an architecture (between stages 2

and 3), while the fourth form is associated with the parallel design of the

individual parts of a particular layout (between stages 3 and 4). For the

third and fourth forms of concurrent design above, necessary interactions,

conflicts, dependencies and trade-off scenarios between either the

subsystems or parts, should be explored. Necessary steps can then be taken

to provide solutions to any bottlenecks. This can be done through a process

of elimination, combination, modification, transference, simplification and

standardisation of the subsystems or parts. Depending on the product type,

either one or a combination or all of the four forms of CDDA, will be

applicable. In the case of the third and fourth forms of concurrent design,

the applicable incidence matrix would be the module-activity matrix,

where module refers to either subsystems of an architecture or parts of a

layout.

27

FIGURE 7. Concurrent Design for Time to Market within Design

Function Deployment

The size of this matrix would depend on the scale and complexity of

the product. Discussions of these four forms of CDDA will be based on

Figure 1.

For static-simple (small scale)-underconstrained (SSU) products, the

second form of CDDA would be more applicable. In the case where the

SSU product has several and/or fairly sizeable parts that can be designed

independently and if considerable effort is required, then there would be

need to employ the fourth form of CDDA. In the case of static-

simple(small scale)-overconstrained (SSO) products (e.g. beverage cans),

no form of CDDA is applicable. The focus for manufacturers of such

products, is usually to improve the manufacturing process. The fourth form

may however be applicable, if a similar condition to that of SSU occurs.

For static-complex-underconstrained (SCU) and static-complex-

overconstrained (SCO) products, the third and fourth forms of CDDA, are

more applicable. The second form may also be applicable to SCU products,

if sufficient resources are available, or if the parallel design can be done by

a different arm or division of the enterprise. Dynamic products are to all

28

intents and purposes underconstrained products. In the case of dynamic-

simple-underconstrained (DSU) products, the first, second and fourth

forms of CDDA are more applicable, while in the case of dynamic-

complex-underconstrained (DCU) products, all four forms of CDDA are

applicable. For both innovative and creative designs, the four forms of

CDDA are also applicable, while in the case of adaptive and variant

designs, only the second, third and fourth forms of CDDA are relevant. It

should be noted that all the four forms of CDDA, go hand in hand with

CDDP.

7.4 Dimensionality of Concurrent Design in Design Function

Deployment

The employment of only CDDP, represents a one- dimensional case in

design concurrency, irrespective of the DFD design stage, and this relates

to SSO products. Here there is no occurrence of CDDA. When either of the

four forms of CDDA are employed in addition to CDDP, then we have a

two-dimensional case of design concurrency, occurring between stages 2

and 4. In the situation where either the third or fourth or both forms of

CDDA are employed in addition to either the first or second or both forms

of CDDA, in addition to CDDP, then we have a three-dimensional

concurrency case, as in DSU and DCU products. For SSU, SCU and SCO

products, the two-dimensional case predominates.

This research work is on-going, and the next stage of the work will

be focussed on how to implement the concepts developed in this section,

within the DFD software system. This is represented as the design

management module in the DFD software architecture shown in Figure 8.

Other research efforts will also go on in parallel as regards modelling

and simulating the design process within DFD using cases studies, as well

as testing the techniques with current practices in industry.

8. MANAGEMENT OF TOOLS FOR TIME TO MARKET

The objectives here are to examine (i) the goals of managing the tools and

resources and (ii) how the management process can be done in line with

concurrent engineering practices. In looking at how the management

process is carried out, the first issue to consider is that the tools and

resources required for each of the activities need to be established. After

this, the explication of the dependencies if any, between the tools, that is,

establish which tool has to be employed to precede another tool (e.g. solid

modelling before Finite element analysis) also need to be explored.

29

FIGURE 8 The Design Function Deployment System Software

Architecture

These dependencies will be influenced mainly by the dependencies that

might exist between each of the design activities. The goal of managing the

design activities is to establish which tasks can be done in parallel and

those that must of necessity be done in series. Having established the

precedence relationships of the design activities, the necessary tools and

resources that have to be employed for each task, can also be established,

using necessary task-tools/resources matrix relationships (tasks listed along

rows, and corresponding tools or resources listed along columns). What we

have here are two matrices of design task-design tools and design task-

resource incidence matrices, where the former shows the tools that are

30

needed to perform particular tasks and the later shows the resources needed

for particular tasks. For more efficient management, these relationships

have to be established for each design stage in DFD.

9. CONCLUSION

It is widely accepted in the manufacturing industry that the speed at which

a product gets to the market place, is a major factor affecting how a

company performs in the market place and represents a key basis for

competition. The main focus of this chapter therefore, has been to address

this major constituent of the ethos of concurrent engineering, that is, the

need to design products for early release to the market place. This has

involved a discussion of the meaning of `Time to Market’, the goals,

objectives, need for and benefits of designing for time to market.

The general requirements which form a basis for achieving the

objectives of design for time to market, have also been discussed. Design

Function Deployment (DFD) - a concurrent engineering design system,

which provides the framework for designing for time to market, was

comprehensively elucidated. Further discussions also involved how to

design for time to market within the platform of DFD. This included

discussions on product classifications, strategic product planning and

fundamental issues affecting design for time to market. The recommended

approach to designing for time to market, was explicitly enunciated. The

chapter concluded with discussions on tools needed to support the process

of designing for time to market, as well as their classifications and

management. The central theme of this chapter, that is, designing for

“Time to Market”, has been demonstrated to be a concurrent engineering

imperative.

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11. ACKNOWLEDGEMENTS

This work was supported by the Engineering and Physical Sciences

Research Council (EPSRC), UK, while the author was at the Engineering

Design Centre, City University, London.

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Design for Time to Market