ARTICLES

Abstract—In the 1980s, companies began to feel the effect of

three major influences on their product development: newer and innovative technologies, increasing product complexity and larger organizations. And therefore companies were forced to look for new product development methods. This paper tries to focus on the two of new product development methods (DFM and CE).

The aim of this paper is to see and analyze different product development methods specifically on Design for Manufacturability and Concurrent Engineering. Companies can achieve and be benefited by minimizing product life cycle, cost and meeting delivery schedule. This paper also presents simplified models that can be modified and used by different companies based on the companies’ objective and requirements.

Methodologies that are followed to do this research are case studies. Two companies were taken and analysed on the product development process. Historical data, interview were conducted on these companies in addition to that, Survey of literatures and previous research works on similar topics has been done during this research. This paper also tries to show the implementation cost benefit analysis and tries to calculate the implementation time.

From this research, it has been found that the two companies did not achieve the delivery time to the customer. Some of most frequently coming products are analyzed and 50% to 80 % of their products are not delivered on time to the customers. The companies are following the traditional way of product development that is sequentially design and production method, which highly affect time to market. In the case study it is found that by implementing these new methods and by forming multi disciplinary team in designing and quality inspection; the company can reduce the workflow steps from 40 to 30.

Keywords—Design for manufacturability, Concurrent

Engineering, Time-to-Market, Product development.

I. INTRODUCTION ESIGN for manufacturability (DFM) is the process of proactively designing products to: a) optimize all the

manufacturing functions: fabrication, assembly test, procurement, shipping, service, and repair; b) assure the best cost, quality, reliability, regulatory compliance, safety, time to market, and customer satisfaction; and c) ensure that lack of manufacturability doesn’t compromise functionality, styling, new product introductions, product delivery, improvement programs, strategic initiatives, and unexpected surges in product demand [5].

Concurrent engineering (CE) is the practice of concurrently developing products and their design and manufacturing processes. If existing processes are to be utilized, then the

Alemu Moges Belay is with University of Vaasa, Finland.

product must be design for these processes. If new processes are to be utilized, then the product and the process must be developed concurrently. This requires knowing a lot about manufacturing processes and one of the best ways to do this is to develop products in multifunctional teams. DFM and CE are proven design methodologies that work for any size company [2]. Early consideration of manufacturing issues shortens product development time, minimizes development cost, and ensures a smooth transition into production for quick time to market.

II. MYTHS AND REALITIES OF PRODUCT DEVELOPMENT Myths of product development

1. To develop products quicker, get going soon on the detail design and software coding and then enforce deadlines to keep design release and first-customer-ship on schedule. 2. To achieve quality, find out what’s wrong and fix it. 3. To customize products, take all orders and use an ad hoc approach: marking up the existing drawings, or having a separate engineering group perform custom engineering on individual products as needed. 4. Cost can be easily reduced by cost reduction efforts after the product is designed [5]

Realities of Product Development 1. The only measure of time-to-market is the time to stable, trouble free production and that depends on getting the design right the first time. 2. The most effective way to achieve quality is to design it in and then build it in. 3. The most effective way to customize products is by the concurrent design of versatile product families and flexible processes, which is known as mass customization. 4. Cost is designed into the product, especially by early concept decisions, and is difficult to remove later.

III. WHEN COST IS COMMITTED Fig. 1 shows that by the time a product is designed, 80% of

the cost has been determined [4]. And by the time a product goes into production, 95% of its cost is determined, so it will be very difficult to remove cost at that late a date. The most profound implication for product development is that 60% of a product’s cumulative lifetime cost is committed by the concept/architecture phase! This is why it is important to fully optimize this phase.

The Toyota philosophy confirms this. ‘‘The cost of a [product] is largely determined at the planning and design stage. Not much in the way of cost improvement can be

Alemu Moges Belay

Design for Manufacturability and Concurrent Engineering for Product Development

D

World Academy of Science, Engineering and Technology International Journal of Mechanical, Aerospace, Industrial, Mechatronic and Manufacturing Engineering Vol:3, No:1, 2009

1International Scholarly and Scientific Research & Innovation 3(1) 2009 scholar.waset.org/1999.8/15800

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expected once full-scale production begins.’’ ‘‘Skillful improvements at the planning and design stage are ten times more effective that at the manufacturing stage.’’

Fig. 1 When cost is committed

Time-to-Market: Time-to-market is a major source of competitive advantage. In fast moving markets, being first to market can have major market share implications. Fig. 2 shows the effect of an early product release on the revenue profile. The shaded area represents the extra sales due to the early introduction. But, since the product development and tooling costs were paid for by the base line sales profile, the shaded area is really extra profit.

Fig. 2 Increasing revenue with early introduction and upgrades

IV. HOW TO CUT IN HALF, THE REAL TIME-TO-MARKET

Time to market is heavily affected by early optimization of the early concept/architecture phase as shown by the Lexmark model in the following Fig. 3. The projected 40% savings in the real time-to-market comes from thorough concept/architecture optimization that minimizes the need for revisions and iterations and makes the manufacturing ramp-up much faster. Note that the architecture phase, labelled ‘’conceptual design’’ went from 3% in the old model to 33%(of the total development time) in the new model, an order of magnitude increase! The more thorough up front work decreased the post-design activities (the revisions, iterations and ramp-up) from almost three-fourths to less than a half of the product development cycle. It is more efficient to

incorporate a balance of design considerations early than to implement the later with changes, revisions and iterations.

Fig. 3 The Lexmark Model True Time to Market differences between linear vs. Concurrent Models. Case study in Mentor graphic

Product innovation and speed of development are becoming

increasingly important in our global economy. Although the role of the product manager in new product development will vary by company, the product manager at minimum should take care in understanding and articulating the market potential and in participating on the product development team. Note that the first step of the new product development process is idea generation [11]. Ideas are fleshed out into a proposal and presented to top management (or a new-product review committee comprised of key executives of all the functional areas) for screening.

For major product ideas/ concepts that pass screening, management assigns representatives from relevant functional areas to a multifunctional project team for this particular new product endeavour. The team members select a leader (who might or might not be the product manager) to organize and monitor the project, guiding it through the critical path schedule developed by the team. All members do as many tasks as possible in parallel (concurrently) to shorten the product development cycle. For example, product managers can conduct focus groups on concept evaluation at the same time that engineering is conducting technical feasibility studies. The dotted line from the concept development and evaluation box to project cancellation box indicates that

World Academy of Science, Engineering and Technology International Journal of Mechanical, Aerospace, Industrial, Mechatronic and Manufacturing Engineering Vol:3, No:1, 2009

2International Scholarly and Scientific Research & Innovation 3(1) 2009 scholar.waset.org/1999.8/15800

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Fig. 4 New product development flow chart

Concepts testing poorly should be considered for elimination as early as possible rather than investing more resources in their development. In general, the stages of new product development can be summarized in the following table.

Fig. 5 Stages in new product development

There is increased pressure to get products of ever-higher

quality to customers in ever-shorter times. Product life cycles

are decreasing as well, and product price/ performance ratios are being scrutinized more carefully. The traditional ‘‘serial’’ approach to product design and development (see Fig. 3) used by many companies today is, therefore, hampering their ability to compete effectively in what is becoming an increasingly global market place for electronic (and other) products.

In serial Engineering environment, design is often done in a relative vacuum [9]. Manufacturing, test, quality and service organizations may not see a design until it is virtually completed. If they raise points during design reviews regarding the difficulty, time, and expense involved in producing the design as presented, they may cause the need for the product to be redesigned.

If a redesign is too expensive or too time consuming, no action will be taken to improve the manufacturability, testability, quality, or serviceability aspects of the product, and it will be more expensive to produce, verify and support than it could (or should) before its entire life. All of these factors hamper competitiveness.

One solution to improving competitiveness is to change from a serial design and development process to a concurrent engineering process (see Fig. 3). The concurrent engineering process treats design for manufacturability, testability, quality, and serviceability attributes (among many others) equally and in parallel with product design for performance attributes such as speed, power consumption, size, weight and reliability. Concurrent engineering integrates the expertise from all of the various engineering disciplines during the actual design phase [8] and the whole focus of concurrent engineering is on a ‘‘right-the-first-time’’ process, rather than on the typical ‘‘redo-until-right’’ process that is so common in the serial engineering mode of operation. The elimination of design iterations reduces product development costs and shortens time to market for new product

V. CASE STUDY ONE

For this particular research, 15 items, which are frequently coming to AEC for the last 5 years, is selected and analyzed. By looking only number wise; out of 15 items, only four are delivered to the customers on time and the rest (11) are delayed due to different reasons, which are indicated on the fish bone diagram on the thesis [1].

The above illustration shows most of the time Addis Engineering Center is not delivering on time for its customers

On time and early delivery = 100 15 4

X =26.67%

Delayed delivery = 100 15 11

X =73.33

STAGE DESCRIPTION RESULT/OUTPUT Idea generation Creation and data

basing of ideas New product proposal

Screening Examination of ideas along pre-established criteria

Assignment of project team

Concept development, testing and evaluation

Refinement of product concept, estimation of customer interest, augmentation of business analysis (financials), go no go decision

Detailed product, market, financial and project plans, product specifications

Proto type development, Testing and evaluation

Physical development of product in R&D; functional and customer testing of the actual product

Final changes to product specifications and production plan

Pre-launch Development of launch strategy; if necessary, market test or simulated market test; initial sales

Finalization of launch document; completion of product training, product support plans, sales collateral, and related written communications

Launch Introduction and marketing of product as detailed in the launch strategy document

New-product launch

Project evaluation

Comparison of results to initial objective

Suggested improvements for future projects

Idea Generation

Concept

screening

Prototype

development,

testing, and

evaluation

Concept

development,

testing, and

evaluation

Project cancellation

Pre-launch

Launch

Project evaluation

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TABLE I SOME OF THE PRODUCTS OF ADDIS ENGINEERING AND PRODUCTION TIME

N O.

ITEMS

QTY

ACTUA L TIME (HRS.) TOTAL

ESTIMAT ED TIME

(HRS.)

TOTAL EFFECT

(HRS)

1 Swash plate 2 58 40 18 (delayed) 2 Template 6 183 258 75 (early) 3 Spinning

disk 1 12 19 7 (early)

4 Punch 1 14:30 8:30 6(delayed) 5 Spline

bushing 1 28 12 16(delayed)

6 Worm shaft 1 7 12 5 (early)

7 Compression spring

500 267 82 185(delayed)

8 Plug gauge 40 290 146 144 (delayed)

9 Bend wire guide

8 26 43 17 (delayed)

10 Bending die 1 37 27 10(delayed)

11 Helical gear 2 26 41 15 (early) 12 shaft 1 62 52 10 (delayed) 13 First male die 1 65 37 28(delayed) 14 Horse shoe

gauge 1 50 27 23(delayed)

15 Female die 5 167 170 3 (early)

-18

75

7

-6 -16

5

-185

-144

-17 -10

15

-10

-28 -23

3

-200

-150

-100

-50

0

50

100

Time (hrs)

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 List of items

Data on delivery delay

Fig. 6 Graphical representation of delivery delay in Addis

Engineering Center

Most customers bring different type of components, which are not in the form of assembly or as a set. Few customers come with components, which require a skill of group technology, which minimizes production time more specifically set up time of the production processes. From the last five years experience, dies are repeatedly coming from different factories and institutions to Addis Engineering Center. Irrespective of their shapes and dimensions or sizes with an average of 15 dies are ordered to be manufactured in AEC. On manufacturing the dies, male die and shank holder could not produced in parallel because it violet design for assembly. Similarly, lower dies and strippers are produced one after the other. The rest components can be produced in parallel so that the production time can be minimized.

TABLE II ITEM WHICH IS MANUFACTURED AS A SET OR ASSEMBLY IN ADDIS

ENGINEERING CENTER Items

QTY

Actual time (hrs.) per pc

Estimated time (hrs.) per pc

Effect Total effect Per Pc.

Male die 15 7 7:30 0:30(early) 7:30 Shank holder

15 5 4 1 (delayed) 15

Longer Bolt

15 6 3 3 (delayed) 45

Punch guide

15 13 11 2 (early) 30

Base plate

15 15 12 3 (delayed) 45

Shorter bolt

15 2 4 2 (early) 30

Spacer 15 9.30 14 4:30 (early) 67:30 Punch holder

15 9 8 1(delayed) 15

Punch (Big)

15 9 9 on time 0

Lower die

15 13 11 2 (delayed) 30

Stripper 15 8 6 2 30

TABLE III CAUSES FOR DELIVERY DELAY AND FREQUENCIES IN ADDIS ENG.

Frequencies in year (E.C)

S/n Delivery delay causes in AEC

1996 1997 1998

Average

(three

years)

1 Modification of

cutters

34 40 38 37.33

2 Availability of

ample Raw

material

32 28 30 30

3 Incomplete

information

from customer

24 20 16 20

4 Maintenance of

machines &

equipments

20 15 13 16

5 Negligence of

operators

16 8 18 14

6 Manufacture

indirect

measurement

8 10 18 12

7 Social factors 10 14 12 12

8 Special work

holding device

12 5 13 10

9 Heat treatment

delay

10 6 8 8

10 Mismatch of

capacity&

availability

2 4 6 4

World Academy of Science, Engineering and Technology International Journal of Mechanical, Aerospace, Industrial, Mechatronic and Manufacturing Engineering Vol:3, No:1, 2009

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Paretho diagram for Addis Engineering

12.25 9.8 8.57

7.357.35 6.12

4.9 2.45

18.37

22.86

0

5

10

15

20

25

1 2 3 4 5 6 7 8 9 10

Causes of Delay

Fr eq

ue nc

y

0

20

40

60

80

100

120

C um

ul at

iv e

%

Fig. 7 Paretho analysis of Addis engineering

Interpretation of the Pareto Curves It is important to identify the vital few from the trivial

money and the paretho analysis is a tool, which is implemented to this research. A useful first step is to draw a vertical line from the 20- 30 percent area of the horizontal axis.

These are often called the vital few, which have been highlighted for a special attention. It is clear that, if the objective is to reduce delay in delivering to the customers, the company should pay attention and eliminate the prolonged time spent modification of cutter and should have proper inventory control and supply system so that the raw materials are supplied on time with the required specifications.

VI. CASE STUDY TWO Dejen aviation maintenance and engineering complex is the

second company for this research that it faces a delivery delay. As it is seen from the above data, one can reach to a conclusion that DAMEC has also a problem on delivering products on time. Mathematically it is possible to put the result as follows:

Products delayed on delivery = 55 31

X 100 = 56.36 %

Early completed jobs = 55 12

X 100 = 21.85 %

WIP and Items not recorded = 55 8

X 100 = 14.54 %

Products completed on time = 55 4

X 100 = 7.27 %

TABLE IV CAUSES FOR DELIVERY DELAY AND FREQUENCIES IN DEJEN AVIA

Paretho diagram for Dejen Aviation

14.87

3.30 1.65

4.98 6.60

9.90

1.65 3.30

33.05

20.66

0

5

10

15

20

25

30

35

1 2 3 4 5 6 7 8 9 10

Causes of delay

Fr eq

ue nc

y

0

20

40

60

80

100

120

C um

ul at

iv e

%

Fig. 8 Paretho analysis of Dejen Aviation

The Paretho analysis in Dejen Aviation Maintenance and

Engineering Complex shows the vital few are availability of ample and quality raw materials and incomplete information that are coming from different departments. By avoiding the problems (delays) caused by these factors, it is possible to minimize the delivery delay, which in turn affects the performance of the company. This and other process like assembling and repairing have direct impact on the overhauling processes of the aircraft.

S/N DELIVERY DELAY CAUSES ( DAMEC)

AVERAGE

(THREE YEARS)

FREQ.

CUM.FRE.

1 Availability of ample Raw

material

33.05 33.05

2 Incomplete information

from customer

20.66 53.71

3 Modification of cutters 14.87 68.58

4 Maintenance of machines

& equipments

9.9 78.48

5 Negligence of operators 6.6 85.08

6 Manufacture indirect

measurement

4.98 90.06

7 Special work holding

device required

3.3 93.36

8 Social factors 3.3 96.66

9 Heat treatment delay 1.65 98.31

10 Mismatch of capacity&

availability

1.65 100

World Academy of Science, Engineering and Technology International Journal of Mechanical, Aerospace, Industrial, Mechatronic and Manufacturing Engineering Vol:3, No:1, 2009

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TABLE V MONETARY BENEFIT OF CONCURRENT ENGINEERING IMPLEMENTATION S.N BENEFIT OBTAINED

FORM CE

ESTIMATED VALUE

OBTAINED (BIRR/YEAR)

1 Increased revenue generation 150,000

2 Benefit from Elimination of

delivery delay

100,000

3 Better employee participation

and communication

50,000

4 Elimination of redesigning

process

100,000

5 Improved customer service

and reducing the scrap

50,000

6 Better ability to manage new

product development

50,000

Total

500,000

Total benefit obtained is 500,000birr per year Total cost required to implement Concurrent engineering is 399,600 birr

Payback period is = 000,500 600,409

year = 0.8192 year.

It is approximately 10 months.

VII. CONCLUSION

Success in manufacturing requires continuous development and improvement of how the products are developed and produced. This paper is done taking two manufacturing companies as a cases tudy. The study depicted or assessed in Addis Engineering center and Dejen Aviation Maintenance and Engineering complex and find out these companies did not achieve the delivery time to the customer. Some of most frequently coming products are analyzed and 60 to 80 % of these products are not delivered on time to the customers.

The companies are following the traditional way of product development that is sequentially design and production method, which highly affect time to market. Time is very important consideration in concurrent engineering. The long workflow of Addis Engineering Center has its influence for the customer requirements on the eyes of achieving the delivery time. By forming multi disciplinary team in designing and quality inspection, the company can reduce the workflow steps from 40 to 30. This in turn reduces the average time for production of a single product from customer order to the delivery of finished products.

The paper tries to show the most common types of activities that affect the production process in AEC and DAMEC. Identifying the types and depths of activities helps the companies to take the remedial action by prioritizing the most occurring and influential ones through production and new product development processes. Concurrent Engineering is not a quick fix for a company's problems. It is a business strategy addresses important company resources. The major objective

DESCRIPTION D1 D2 D3 D4 ESTIMATED COST

Preparation Phase workshop on concurrent engineering by external professionals for Top management CE steering committee formation from TOP management team CE attitude survey (profile of organization, quality costs, organization strength/weakness, advocators & resistors.

21 days

Training cost, lost time of 30 persons @120 birr per person per day =75,600 birr

Planning Phase Strategic planning workshop (By CE steering committee): Create vision, guiding principles, set broad strategic objectives, develop quality policy, identify critical success factors& critical processes, baseline employee satisfaction and customer satisfaction. Plan the implementation approach and asses the implementation guide.

10 days

Workshop running expenses, lost time of 30 persons @100 birr per person per day, =30,000 birr

Execution Phase Form multidisciplinary teams/site steering committees from each department and identify team facilitators. Specific training and team-forming workshops for site steering committees. create awareness on customer/ supplier relationship Company-wide implementation/improvem ent projects for CE (CE Value, customer/supplier frame work, systems and techniques). Modify infrastructures as necessary (procedures/processes, organizational structure, reward/recognition system, union rules etc.)

70 days

For 60 Lost time@70birr per person per day, training costs, Lost services because of inefficiency during first months, 294,000 birr

5 days

10,000 birr Evaluation Phase Feedback/ follow-up workshops

Tota l

106 days

409,600 birr

Fig. 9 Concurrent engineering Implementation plan in Addis engineering

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this business strategy aims to achieve is improved product development performance. Concurrent Engineering is a long- term strategy, and it should be considered only by organizations willing to make up front investments and might need years for long-term benefits. The implementation guide, which is presented in this paper, is simplified and can be implemented with out sophisticated software applications in different industries. This could be achieved by forming multi disciplinary team.

REFERENCES [1] Alemu Moges, “concurrent Engineering and Its Implementation’’

Thesis, AAU, 2007. [2] Donald E. Carter and Barbara stilwell Baker “Concurrent Engineering,’’

The product development Environment for the 1990s, Addison Wesley Publishing Company, INC, 1992.

[3] Donald G. Reinertsen, “Managing the Design Factory,’’ A product developer’s Toolkit, New York, THE FREE PRESS, 1997.

[4] Dr. David M. Anderson, “Design for Manufacturability, “Optimizing Cost, Quality and Time-to-Market, California, CIM Press, 1990.

[5] Dr. David M. Anderson, “Design for Manufacturability & Concurrent Engineering,’’ How to design for low cost, Design in High quality, Design for lean Manufacture, and Design quickly for fast production, CIM Press, 2008.

[6] G. Boothroyd, Geoffrey Boothroyd, Winston A. Knight, W. A. Knight, Peter Dewhurst, Winston Knight, product design for manufacture and assembly, January 2002.

[7] Hamid R Parasaei ad William G. Sullivan “Concurrent Engineering Contemporary issues and modern design tools” Chapman and Hall 1993.

[8] John R. Hartley, Concurrent Engineering: Shortening Lead Times, Raising Quality, and Lowering Costs, January 1992.

[9] Jon Turino, “Managing Concurrent Engineering,’’ buying time to market, Campbell, CA, 1992.

[10] Kitaw Daniel “industrial management and Engineering economy faculty of Technology, AAU, 2004.

[11] Linda Gorchels, “The product manager’s handbook,’’ USA, NTC business book, 1997.

[12] Morten karlsson “Green Concurrent engineering, a model for DFE management programs “Lund University Doctor Dissertation”

[13] Perston G. Smith, Donald G. Reinertsen “Developing Products in Half the Time,’’ New rules, new tools, second edition, 1998.

[14] Remko W. Helms “Product data management as enablers for concurrent engineering “ Endhoven University of Technology, 2002.

[15] Soumitra Dutta and Jean-Francois Manzoni, “Process Re-engineering organizational change and performance improvement,’’ McGraw-Hill Publication, 1999.

[16] Ulrich K.T, Eppinger S.D ‘‘product design and development’’ McGraw hill London 1995.

[17] William D. Falcon (editor) “Value analysis Value Engineering,’’ the implication for Managers, The American association New York, 1964.

[18] Winner R.J. Pennel J. P Bertrand H.E, Slusarczuk MM, “the role of Concurrent Engineering in weapons systems Acquisition’’ IDA R-338 Institute for defence analyses, 1998.

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