Design has a tremendous impact on the quality of a product or service. Poor designs may not meet customer needs or may be so difficult to make that quality suffers. Costly designs can result in overpriced products that lose market share. If the design process is too lengthy, a competitor may capture the market by being the first to introduce new products, services, or features. However, rushing to be first to the market can result in design flaws and poor performance, which totally negate first-mover advantages. Design may be an art, but the design process must be managed effectively.

An effective design process:

Product design defines the appearance of the product, sets standards for performance, specifies which materials are to be used, and determines dimensions and tolerances. Figure 4.1 outlines the design process from idea generation to product launch. Let's examine each step in detail.

IDEA GENERATION

The design process begins with understanding the customer and actively identifying customer needs. Ideas for new products or improvements to existing products can be generated from many sources, including a company's own R&D department, customer complaints or suggestions, marketing research, suppliers, salespersons in the field, factory workers, and new technological developments. Competitors are also a source of ideas for new products or services. Perceptual maps, benchmarking, and reverse engineering can help companies learn from their competitors.

Figure 4.1. The Design Process

Figure 4.2. A Perceptual Map of Breakfast Cereals

Perceptual maps compare customer perceptions of a company's products with competitors' products. Consider the perceptual map of breakfast cereals in terms of taste and nutrition shown in Figure 4.2. The lack of an entry in the good-taste, high-nutrition category suggests there are opportunities for this kind of cereal in the market. This is why Cheerios introduced honey-nut and apple-cinnamon versions while promoting its "oat" base. Fruit bits and nuts were added to wheat flakes to make them more tasty and nutritious. Shredded Wheat opted for more taste by reducing its size and adding a sugar frosting or berry filling. Rice Krispies, on the other hand, sought to challenge Cocoa Puffs in the "more tasty" market quadrant with marshmallow and fruit-flavored versions.

Perceptual map: visual method of comparing customer perceptions of different products or services.

Benchmarking refers to finding the best-in-class product or process, measuring the performance of your product or process against it, and making recommendations for improvement based on the results. The benchmarked company may be in an entirely different line of business. For example, American Express is well known for its ability to get customers to pay up quickly; Disney World, for its employee commitment; Federal Express, for its speed; McDonald's, for its consistency; and Xerox, for its benchmarking techniques.

Benchmarking: comparing a product or process against the best-in-class product.

Reverse engineering refers to carefully dismantling and inspecting a competitor's product to look for design features that can be incorporated into your own product. Ford used this approach successfully in its design of the Taurus automobile, assessing 400 features of competitors' products and copying, adapting, or enhancing more than 300 of them, including Audi's accelerator pedal, Toyota's fuel-gauge accuracy, and BMW's tire and jack storage.

Reverse engineering: carefully dismantling a competitor's product to improve your own product.

For many products and services, following consumer or competitors' leads is not enough; customers are attracted by superior technology and creative ideas. In these industries, research and development is the primary source of new product ideas. Expenditures for R&D can be enormous ($2 million a day at Kodak!) and investment risky (only 1 in 20 ideas ever becomes a product and only 1 in 10 new products is successful). In addition, ideas generated by R&D may follow a long path to commercialization.

Read about Pixar's creative design process in the "Along the Supply Chain" box on the next page.

FEASIBILITY STUDY

Marketing takes the ideas that are generated and the customer needs that are identified from the first stage of the design process and formulates alternative product and service concepts. The promising concepts undergo a feasibility study that includes several types of analyses, beginning with a market analysis. Most companies have staffs of market researchers who can design and evaluate customer surveys, interviews, focus groups, or market tests. The market analysis assesses whether there's enough demand for the proposed product to invest in developing it further.

If the demand potential exists, then there's an economic analysis that looks at estimates of production and development costs and compares them to estimated sales volume. A price range for the product that is compatible with the market segment and image of the new product is discussed. Quantitative techniques such as cost/benefit analysis, decision theory, net present value, or internal rate of return are commonly used to evaluate the profit potential of the project. The data used in the analysis are far from certain. Estimates of risk in the new product venture and the company's attitude toward risk are also considered.

A feasibility study consists of a market analysis, an economic analysis, and a technical/strategic analysis.

ALONG THE SUPPLY CHAIN

Pixar'S Creativity

Pixar is a wildly creative animation studio that has produced 10 blockbuster movies in a row. President Ed Catmull, a creative designer himself, shares the secrets of Pixar's success, summarized below.

Creative Control Ideas for new animation projects in most companies come from outside development departments. Not at Pixar. No scripts or movie ideas have ever been bought. Ideas are generated internally from directors, designers, artists, writers, storyboarders, animators, and any one of the 200- to 250-member crew. The team has ownership at every stage of the project. Buy-in and commitment are assured.

A Peer Culture People at all levels need to support one another's efforts. Pixar encourages "collective genius" by creating a safe environment where ideas and work can be discussed and critiqued. Daily animation work is shown in its incomplete state to the entire crew. Team members get used to sharing unfinished work and accepting feedback.

Freed-up Communication The most effective way to solve problems or coordinate efforts is through direct communication, regardless of department, rank, or position. Pixar does not believe in a rigid chain of command or permissions-based communication.

A Learning Environment Pixar views learning as a fun, collective, and expected process. Staffs at all levels are trained in multiple skill sets at Pixar University so that people from different disciplines can learn to interact with each other.

Post-Mortems No one likes to talk about what went wrong with a project, so Pixar makes it easier by asking each participant to list the top five things they would do again and the top five things they would do differently in a project. Plentiful data to review also helps keep the review process objective and focused.

Hands-off Managing There is no micromanaging at Pixar. Management sets the budget and project timelines but leaves the director and his team alone to finish the project. Even when a director runs into trouble, management will add additional members with the skills to help to the team, but they will not take control of the process. If all else fails, they'll change directors rather than step in themselves.

1. What do you think sets Pixar movies apart from other animations?

2. How would you incorporate Pixar's ideas on innovation in other types of companies?

3. Research the process of creating an animated movie. Discuss the levels of detail, coordination, and iterative processes that are required to successfully finish a project.

   How do you think quality of design is maintained?

Source: Adapted from Ed Catmull, "How Pixar Fosters Creativity," Harvard Business Review, September 2008; Pixar Web site http://www.pixar.com/howwedoit/index.html#.

Finally, there are technical and strategic analyses that answer such questions as: Does the new product require new technology? Is the risk or capital investment excessive? Does the company have sufficient labor and management skills to support the required technology? Is sufficient capacity available for production? Does the new product provide a competitive advantage for the company? Does it draw on corporate strengths? Is it compatible with the core business of the firm?

Performance specifications are written for product concepts that pass the feasibility study and are approved for development. They describe the function of the product—that is, what the product should do to satisfy customer needs.

The next step in the process is rapid prototyping.

Designers take general performance specifications and transform them into a physical product or service with technical design specifications. The process involves building a prototype, testing the prototype, revising the design, retesting, and so on until a viable design is determined.

Figure 4.3. Concurrent Design, Breaking Down Barriers

Rapid prototyping, as the name implies, creates preliminary design models that are quickly tested and either discarded (as fast failures) or further refined. The models can be physical or electronic, rough facsimiles or full-scale working models. The iterative process involves form and functional design, as well as production design.

It is important that these design decisions be performed concurrently at the rapid prototype stage. Design decisions affect sales strategies, efficiency of manufacture, assembly quality, speed of repair, and product cost. Design decisions overlap and early changes in the design are less disruptive than those made late in the process. Effective designs, as shown in Figure 4.3, break down the series of walls between functional areas and involve persons from different backgrounds and areas of expertise early in the design process. This process of jointly and iteratively developing a design is called concurrent design.

Rapid prototyping: creating, testing, and revising a preliminary design model.

Concurrent design improves both the quality of the design and the time-to-market. This is especially true with the design of component parts to be completed by a supplier. Rather than designing the parts and giving the design specs to a supplier to complete, concurrent design involves the supplier in the design process. For example, a company may share with a potential supplier the performance specs and ask the supplier to complete the design so that the part performs properly and fits with space, weight, and cost parameters.

Concurrent design: a new approach to design that involves the simultaneous design of products and processes by design teams.

In the next sections, we discuss the three types of concurrent designs: form, functional, and production design.

FORM DESIGN

Form design refers to the physical appearance of a product—its shape, color, size, and style. Aesthetics such as image, market appeal, and personal identification are also part of form design. In many cases, functional design must be adjusted to make the product look or feel right. For example, the form design of Mazda's Miata sports car went further than looks—the exhaust had to have a certain "sound," the gearshift lever a certain "feel," and the seat and window arrangement the proper dimensions to encourage passengers to ride with their elbows out. Apple products have great form and functional design. Read about Apple's design process in the "Along the Supply Chain" box on the next page.

Form design: how the product will look.

ALONG THE SUPPLY CHAIN

Apple's Design Process

No discussion of innovation and design would be complete without examining BusinessWeek's perennial "No. 1 Most Innovative Company," Apple. Both Apple's product and service design prowess are legendary. Michael Lopp, senior engineering manager at Apple, describes his company's approach to design as delivering a series of presents to the customer, "really good ideas wrapped up in other really good ideas" (i.e., pioneering software in elegant hardware in beautiful packaging) to replicate that Christmas morning experience. Apple moves fast, constantly innovates, and is never satisfied. More than understanding customer needs, they anticipate what will delight customers in the future. Although Apple has received many design accolades, little is known about their design process. Four of their techniques, presented below, were revealed during a panel discussion at a recent SXSW (South-by-Southwest) Interactive Conference.

• Pixel Perfect Mockups Detailed mockups (e.g., prototypes) take a long time to construct but prevent misunderstandings and mistakes later on in the process.

• 10 to 3 to 1 Designers create ten completely different detailed mock-ups which are then reduced to three. After several more months of work, those three are reduced to one final design. Not many companies would be willing to discard 90% of their design work to come up with the perfect design.

• Paired Design Meetings Every week the engineers and designers have two meetings—a brainstorming meeting with no-holds-barred free thinking, and a production meeting to critique ideas and decide how to make them work. This continues throughout the development process. It is highly unusual to encourage creative thinking in the later stages of a design, or to start over when better ideas are generated, something CEO Steve Jobs has been known to do.

• Pony Meetings Top managers are famous for the "I want a pony" syndrome of pie-in-the-sky ideas. Design teams have regular meetings with execs to inform them of pony status and to keep them in the loop during the design process. This eliminates surprises and disappointments later on.

The Apple design team of 20 people is quite small, with an international flair of German, British, New Zealand, and Italian designers, in addition to U.S. designers. Design chief Jonathan Ives prefers to invest his dollars in state-of-the-art prototyping equipment rather than large numbers of people. However, these designers work closely with engineers, marketers, and manufacturing contractors in Asia who actually build the products. Not surprisingly, Apple is a leading innovator in materials, tooling, and manufacturing technology such as injection molding, as well as electronic technology.

Apple gloats that it does no market research, nor does it spread risk by diversifying its products. Instead Apple concentrates its resources on just a few products and makes them extremely well. They use their own technology and take the time to immerse themselves in the user experience. The process begins by asking, "What do we hate? What do we have the technology to do? What would we like to own?" Meticulous designers take it from there—designers who dream up products so ingenious that whole industries are upended.

1. What about Apple-designed products do you find special as a consumer?

2. Why have no competitors caught up with Apple?

   Do you think Apple can sustain its success with so few products?

3. What would you ask Apple to design next?

Sources: Betsy Morris, "What Makes Apple Golden," Fortune, (March 3, 2008); Alain Breillatt, "You Can't Innovate Like Apple," posted March 21, 2008, retrieved from http://pictureimperfect.net/2008/03/21/you-cant-innovate-like-apple/; Helen/Walters, "Apple's Design Process," BusinessWeek Online (March 2008), retrieved from http://www.businessweek.com/thwe_thread/techbeat/archives/2008/03/apples_design_p.html; M.G. Siegler, "The Wonders of Apple's Tablet," The Washington Post (December 25, 2009).

RELIABILITY

Reliability is the probability that a given part or product will perform its intended function for a specified length of time under normal conditions of use. You may be familiar with reliability information from product warranties. A hair dryer might be guaranteed to function (i.e., blow air with a certain force at a certain temperature) for one year under normal conditions of use (defined to be 300 hours of operation). A car warranty might extend for three years or 50,000 miles. Normal conditions of use would include regularly scheduled oil changes and other minor maintenance activities. A missed oil change or mileage in excess of 50,000 miles in a three-year period would not be considered "normal" and would nullify the warranty.

Reliability: the probability that a product will perform its intended function for a specified period of time.

A product or system's reliability is a function of the reliabilities of its component parts and how the parts are arranged. If all parts must function for the product or system to operate, then the system reliability is the product of the component part reliabilities.

R_s = (R₁)(R₂) . . . (R_n), where R_n is the reliability of the nth component.

For example, if two component parts are required and each has a reliability of 0.90, the reliability of the system is 0.90 × 0.90 × 0.81, or 81%. The system can be visualized as a series of components as follows:

Note that the system reliability of 0.81 is considerably less than the component reliabilities of 0.90. As the number of serial components increases, system reliability will continue to deteriorate. This makes a good argument for simple designs with fewer components!

Failure of some components in a system is more critical than others—the brakes on a car, for instance. To increase the reliability of individual parts (and thus the system as a whole), redundant parts can be built in to back up a failure. Providing emergency brakes for a car is an example. Consider the following redundant design with R₁ representing the reliability of the original component and R₂ the reliability of the backup component.

These components are said to operate in parallel. If the original component fails (a 5% chance), the backup component will automatically kick in to take its place—but only 90% of the time. Thus, the reliability of the system is^[9]

Reliability

Determine the reliability of the system of components shown below.

Solution

First, reduce the system to a series of three components,

Then calculate the reliability of the series.

Reliability can also be expressed as the length of time a product or service is in operation before it fails, called the mean time between failures (MTBF). In this case, we are concerned with the distribution of failures over time, or the failure rate. The MTBF is the reciprocal of the failure rate (MTBF = 1/failure rate). For example, if your laptop battery fails four times in 20 hours of operation, its failure rate would be 4/20 = 0.20, and its MTBF = 1/0.20 = 5 hours.

Reliability can be improved by simplifying product design, improving the reliability of individual components, or adding redundant components. Products that are easier to manufacture or assemble, are well maintained, and have users who are trained in proper use have higher reliability.

MAINTAINABILITY

•Maintainability: the ease with which a product is maintained or repaired.

Maintainability (also called serviceability) refers to the ease and/or cost with which a product or service is maintained or repaired. Products can be made easier to maintain by assembling them in modules, like computers, so that entire control panels, cards, or disk drives can be replaced when they malfunction. The location of critical parts or parts subject to failure affects the ease of disassembly and, thus, repair. Instructions that teach consumers how to anticipate malfunctions and correct them themselves can be included with the product. Specifying regular maintenance schedules is part of maintainability, as is proper planning for the availability of critical replacement parts.

One quantitative measure of maintainability is mean time to repair (MTTR). Combined with the reliability measure of MTBF, we can calculate the average availability or "uptime" of a system as

System Availability

Amy Russell must choose a service provider for her company's e-commerce site. Other factors being equal, she will base her decision on server availability. Given the following server performance data, which provider should she choose?

Provider	MTBF (hr)	MTTR (hr)
A	60	4.0
B	36	2.0
C	24	1.0

Solution

Amy should choose Provider C.

USABILITY

All of us have encountered products or services that are difficult or cumbersome to use. Consider:

• Cup holders in cars that, when in use, hide the radio buttons or interfere with the stick shift.

• Salt shakers that must be turned upside down to fill (thereby losing their contents).

• Speakers in laptop computers that are covered by your wrists as you type.

• Doors that you can't tell whether to pull or push.

• Remote controls with more and more buttons of smaller and smaller size for multiple products.

• Levers for popping the trunk of a car and unlocking the gas cap located too close together.

Usability: ease of use of a product or service.

These are usability issues in design. Usability is what makes a product or service easy to use and a good fit for its targeted customer. It is a combination of factors that affect the user's experience with a product, including ease of learning, ease of use, and ease of remembering how to use, frequency and severity of errors, and user satisfaction with the experience.

Although usability engineers have long been a part of the design process, their use has sky-rocketed with electronics, computer software, and Web site design. Forrester Research estimates that 50% of potential sales from Web sites are lost from customers who cannot locate what they need. Researchers have found that Internet users have a particularly low tolerance for poorly designed sites and cumbersome navigation.

Apple revolutionized the computer industry with its intuitive, easy-to-use designs and continues to do so with its sleek and functional iPods, iPads, and iPhones. Microsoft employs over 140 usability engineers. Before a design is deemed functional, it must go through usability testing. Simpler, more standardized designs are usually easier to use. They are also easier to produce, as we'll see in the next section.

PRODUCTION DESIGN

• Production design: how the product will be made.

Production design is concerned with how the product will be made. Designs that are difficult to make often result in poor-quality products. Engineers tend to overdesign products, with too many features, options, and parts. Lack of knowledge of manufacturing capabilities can result in designs that are impossible to make or require skills and resources not currently available. Many times, production personnel find themselves redesigning products on the factory floor. Late changes in design are both costly and disruptive. An adjustment in one part may necessitate an adjustment in other parts, "unraveling" the entire product design. That's why production design is considered in the preliminary design phase. Recommended approaches to production design include simplification, standardization, modularity, and design for manufacture.

Figure 4.4. Design Simplification Source: Adapted from G. Boothroyd and P. Dewhurst, "Product Design. . . . Key to Successful Robotic Assembly," Assembly Engineering (September 1986), pp. 90–93.

Design simplification attempts to reduce the number of parts, subassemblies, and options in a product. It also means avoiding tools, separate fasteners, and adjustments. We'll illustrate simplification with an example. Consider the case of the toolbox shown in Figure 4.4. The company wants to increase productivity by using automated assembly. The initial design in Figure 4.4a contains 24 common parts (mostly nuts and bolts fasteners) and requires 84 seconds to assemble. The design does not appear to be complex for manual assembly but can be quite complicated for a robot to assemble.

• Simplification: reduces the number of parts, assemblies, or options in a product.

As shown in Figure 4.4b, the team assigned to revise the design simplified the toolbox by molding the base as one piece and eliminating the fasteners. Plastic inserts snap over the spindle to hold it in place. The number of parts was reduced to four, and the assembly time cut to 12 seconds. This represents a significant gain in productivity, from 43 assemblies per hour to 300 assemblies per hour.

Figure 4.4c shows an even simpler design, consisting of only two parts, a base and spindle. The spindle is made of flexible material, allowing it to be snapped downward into place in a quick, one-motion assembly. Assembly time is reduced to 4 seconds, increasing production to 900 assemblies an hour. With this final design, the team agreed that the assembly task was too simple for a robot. Indeed, many manufacturers have followed this process in rediscovering the virtues of simplification—in redesigning a product for automation, they found that automation isn't necessary!

Standardization: when commonly available and interchangeable parts are used.

Using standard parts in a product or throughout many products saves design time, tooling costs, and production worries. Standardization makes possible the interchangeability of parts among products, resulting in higher-volume production and purchasing, lower investment in inventory, easier purchasing and material handling, fewer quality inspections, and fewer difficulties in production. Some products, such as light bulbs, batteries, and DVDs, benefit from being totally standardized. For others, being different is a competitive advantage. The question becomes how to gain the cost benefits of standardization without losing the market advantage of variety and uniqueness.

Modular design: combines standardized building blocks, or modules, to create unique finished products.

One solution is modular design. Modular design consists of combining standardized building blocks, or modules, in a variety of ways to create unique finished products. Modular design is common in the electronics industry and the automobile industry. Toyota's Camry, Corolla, and Lexus share the same body chassis. Even Campbell's Soup Company practices modular design by producing large volumes of four basic broths (beef, chicken, tomato, and seafood bisque) and then adding special ingredients to produce 125 varieties of final soup products.

Design for manufacture (DFM) is the process of designing a product so that it can be produced easily and economically. The term was coined in an effort to emphasize the importance of incorporating production design early in the design process. When successful, DFM not only improves the quality of product design but also reduces both the time and cost of product design and manufacture.

Specific DFM software can recommend materials and processes appropriate for a design and provide manufacturing cost estimates throughout the design process. More generally, DFM guidelines promote good design practice, such as:

• Design for manufacture DFM): designing a product so that it can be produced easily and economically.

1. Minimize the number of parts and subassemblies.

2. Avoid tools, separate fasteners, and adjustments.

3. Use standard parts when possible and repeatable, well-understood processes.

4. Design parts for many uses, and modules that can be combined in different ways.

5. Design for ease of assembly, minimal handling, and proper presentation.

6. Allow for efficient and adequate testing and replacement of parts.

New products for more segmented markets have proliferated over the past decade. Changes in product design are more frequent, and product lifecycles are shorter. IBM estimates the average life of its new product offerings is about six months. The ability to get new products to the market quickly has revolutionized the competitive environment and changed the nature of manufacturing.

Part of the impetus for the deluge of new products is the advancement of technology available for designing products. It begins with computer-aided design (CAD) and includes related technologies such as computer-aided engineering (CAE), computer-aided manufacturing (CAM), and collaborative product design (CPD).

• Computer-aided design (CAD): assists in the creation, modification, and analysis of a design

Computer-aided design (CAD) is a software system that uses computer graphics to assist in the creation, modification, and analysis of a design. A geometric design is generated that includes not only the dimensions of the product but also tolerance information and material specifications. The ability to sort, classify, and retrieve similar designs from a CAD database facilitates standardization of parts, prompts ideas, and eliminates building a design from scratch.

CAD-generated products can also be tested more quickly. Engineering analysis, performed with a CAD system, is called computer-aided engineering (CAE). CAE retrieves the description and geometry of a part from a CAD database and subjects it to testing and analysis on the computer screen without physically building a prototype. CAE can maximize the storage space in a car trunk, detect whether plastic parts are cooling evenly, and determine how much stress will cause a bridge to crack. With CAE, design teams can watch a car bump along a rough road, the pistons of an engine move up and down, a golf ball soar through the air, or the effect of new drugs on virtual DNA molecules. Advances in virtual reality and motion capturing technology allow designers and users to experience the design without building a physical prototype.

• Computer-aided engineering (CAE) a software system that tests and analyzes designs on the computer screen.

Computer-aided design (CAD) is used to design everything from pencils to submarines. Some of our everyday products are more difficult to design than you may think. Potato chips with ridges, the top of a soda can, a two-liter bottle of soft drink, a car door, and golf balls are examples of simple products that require the sophistication of CAD for effective design and testing. Shown here are two examples of dimple design on Titleist golf balls. The number, size, and patterns of dimples on a golf ball can affect the distance, trajectory, and accuracy of play. The advent of CAD has allowed many more designs to be tested. Today, more than 200 different dimple patterns are used by golf-ball manufacturers. Golf clubs and golf courses are also designed using CAD.

• computer-aided design/computer-aided manufacturing (CAD/CAM): the ultimate design-to-manufacture connection.

CAD and its related technologies produce better designs faster.

The ultimate design-to-manufacture connection is a computer-aided design/computer-aided manufacturing (CAD/CAM) system. CAM is the acronym for computer-aided manufacturing. CAD/CAM involves the automatic conversion of CAD design data into processing instructions for computer-controlled equipment and the subsequent manufacture of the part as it was designed. This integration of design and manufacture can save enormous amounts of time, ensure that parts and products are produced precisely as intended, and facilitate revisions in design or customized production.

Besides the time savings, CAD and its related technologies have also improved the quality of designs and the products manufactured from them. The communications capabilities of CAD may be more important than its processing capabilities in terms of design quality. CAD systems enhance communication and promote innovation in multifunctional design teams by providing a visual, interactive focus for discussion. Watching a vehicle strain its wheels over mud and ice prompts ideas on product design and customer use better than stacks of consumer surveys or engineering reports. New ideas can be suggested and tested immediately, allowing more alternatives to be evaluated. To facilitate discussion or clarify a design, CAD data can be sent electronically between designer and supplier or viewed simultaneously on computer screens by different designers in physically separate locations. Rapid prototypes can be tested more thoroughly with CAD/CAE. More prototypes can be tested as well. CAD improves every stage of product design and is especially useful as a means of integrating design and manufacture.

• Product lifecycle management (PLM): managing the entire lifecycle of a product.

With so many new designs and changes in existing designs, a system is needed to keep track of design revisions. Such a system is called product lifecycle management (PLM). PLM stores, retrieves, and updates design data from the product concept, through manufacturing, revision, service, and retirement of the product.

Before finalizing a design, formal procedures for analyzing possible failures and rigorously assessing the value of every part and component should be followed. Three such techniques are failure mode and effects analysis, fault tree analysis, and value analysis.

• Failure mode and effects analysis (FMEA): a systematic method of analyzing product failures.

Failure mode and effects analysis (FMEA) is a systematic approach to analyzing the causes and effects of product failures. It begins with listing the functions of the product and each of its parts. Failure modes are then defined and ranked in order of their seriousness and likelihood of failure. Failures are addressed one by one (beginning with the most catastrophic), causes are hypothesized, and design changes are made to reduce the chance of failure. The objective of FMEA is to anticipate failures and prevent them from occurring. Table 4.1 shows a partial FMEA for potato chips.

• Fault tree analysis (FTA): a visual method for analyzing the interrelationships among failures.

Fault tree analysis (FTA) is a visual method of analyzing the interrelationship among failures. FTA lists failures and their causes in a tree format using two hatlike symbols, one with a straight line on the bottom representing and and one with a curved line on the bottom for or. Figure 4.5 shows a partial FTA for a food manufacturer who has a problem with potato chip breakage. In this analysis, potato chips break because they are too thin or because they are too brittle. The options for fixing the problem of too-thin chips—increasing thickness or reducing size—are undesirable, as indicated by the Xs. The problem of too-brittle chips can be alleviated by adding more moisture or having fewer ridges or adjusting the frying procedure. We choose to adjust the frying procedure, which leads to the question of how hot the oil should be and how long to fry the chips. Once these values are determined, the issue of too-brittle chips (and thus chip breakage) is solved, as indicated.

• Value analysis (VA): a procedure for eliminating unnecessary features and functions.

Value analysis (VA) (also known as value engineering) was developed by General Electric in 1947 to eliminate unnecessary features and functions in product designs. It has reemerged as a technique for use by multifunctional design teams. The design team defines the essential functions of a component, assembly, or product using a verb and a noun. For example, the function of a container might be described as holds fluid. Then the team assigns a value to each function and determines the cost of providing the function. With that information, a ratio of value to cost can be calculated for each item. The team attempts to improve the ratio by either reducing the cost of the item or increasing its worth. Updated versions of value analysis also assess the environmental impact of materials, parts, and operations. This leads us to the next section on design for environment.

Figure 4.5. Fault Tree Analysis for Potato Chips

The EPA estimates that close to 4 billion electronic devices (computers, televisions, cell phones, printers, etc.) representing 2 trillion tons of waste are disposed of each year in the United States alone. At most 20% of that waste is recycled. The rest enters landfills either here or overseas where e-waste reclamation can present severe environmental and health problems. Images of overflowing landfills, toxic streams, and global warming have prompted governments worldwide to enact laws and regulations protecting the environment and rewarding environmental stewardship.

• Extended producer responsibility (EPR): when companies are held responsible for their product even after its useful life.

Extended producer responsibility (EPR) is a concept that holds companies responsible for their product even after its useful life. German law mandates the collection, recycling, and safe disposal of computers and household appliances, including stereos and video appliances, televisions, washing machines, dishwashers, and refrigerators. Some manufacturers pay a tax for recycling; others include the cost of disposal in a product's price. Norwegian law requires producers and importers of electronic equipment to recycle or reuse 80% of the product. Nineteen U.S. states now have takeback laws that require the return and recycling of batteries, appliances, and other electronics. Brazil considers all packaging that cannot be recycled hazardous waste. The European Union requires that 80% of the weight of discarded cars must be reused or recycled. Companies responsible for disposing of their own products are more conscious of the design decisions that generated the excess and toxic waste that can be expensive to process.

• eco-labeling: a seal of approval for environmentally safe products.

• carbon footprint: a measure of greenhouse gases.

Eco-labeling, such as Germany's Blue Angel designation (see Figure 4.6) or the United States's Energy Star rating, gives the seal of approval to environmentally safe products and encourages informed consumer purchase. Carbon footprints measure the amount of carbon dioxide (CO₂) and other greenhouse gases that contribute to global warming and climate change. A product's carbon footprint is calculated by estimating the greenhouse gas emissions from the energy used in manufacturing and transporting the product along its supply chain, the energy used in stocking and selling the product, the energy used by the consumer in using the product, and the energy used to recycle and dispose of the product at the end of its useful life. Carbon footprints are part of a more comprehensive lifecycle assessment initiative supported by IS0 14000 environmental standards. IS0 14000 standards provide guidelines and certifications for environmental requirements of doing business in certain countries, and is often used to qualify for foreign aid, business loans, and reduced insurance premiums.

Figure 4.6. International Eco-labels: These eco-labels are from the European Union, Germany, Korea, Japan, Norway, Taiwan, Germany, Canada, and the United States. Source: http://www.gdrc.org/sustbiz/green/doc-label_programmes.html

• Sustainability: meeting present needs without compromising future generations.

Sustainability, the ability to meet present needs without compromising those of future generations, is a lofty goal, but companies worldwide are beginning to discover the cost savings and consumer goodwill that green practices provide. For example, by eliminating excessive packaging on its private label toy line, Walmart saved $2.4 million a year in shipping costs, 3,800 trees, and 1 million barrels of oil. Installing auxiliary power sources in its fleet of trucks (instead of idling the engine while drivers sleep) saved $26 million in fuel costs. Bailing plastic refuse for recycling and resale provided an additional $28 million in additional revenue. Buoyed by these successes, Walmart began mandating that its suppliers meet certain environmental (and cost saving) standards such as reduced packaging, condensed liquids, green product formulations, and sustainable design. A sustainability scorecard for suppliers is now included in eco-labeling of Walmart products. For companies that supply Walmart and other large corporations, it became evident that the place to start meeting environmental requirements is with green product design, or what is more globally referred to as design for environment (DFE).

• Design for environment (DFE): designing a product from material that can be recycled or easily repaired rather than discarded.

Design for environment (DFE) involves many aspects of design, such as designing products from recycled material, reducing hazardous chemicals, using materials or components that can be recycled after use, designing a product so that it is easier to repair than discard, and minimizing unnecessary packaging. As shown in Figure 4.7, it extends across the product lifecycle from raw material sourcing to manufacture to consumer use and end-of-life recycling, re-use, or disposal. We discuss each of these areas below.

GREEN MANUFACTURE

In the manufacturing process, green design is concerned with the energy needed to produce the product, whether that energy is renewable, how much waste or harmful by-products are generated from the process, and if that waste can be recycled or by-product disposed of safely. Production should be in the proper amounts so that inventory is minimized, and the manufacturing plant should be located in close proximity to customers to minimize transportation and its affect on greenhouse gas emissions. The product should have minimal packaging and the boxes or bins used for transportation should be re-usable.

Figure 4.7. Design for Environment Lifecycle

A manufacturing plant's carbon footprint can be determined from the processing, waste, and transport that takes place. Recycling, renewable resources, clean energy, efficient operations, and proper waste disposal can help mitigate the environmental impact of manufacturing.

RECYCLING AND RE-USE

When a product reaches the end of its useful life, it can be recycled, reused, or discarded (usually to a landfill). Design factors such as product life, recoverable value, ease of repair, and disposal cost affect the decision to recycle, discard, or continue to use. Many products are discarded because they are difficult or expensive to repair. Materials from discarded products may not be recycled if the product is difficult to disassemble. That's why companies like Hewlett-Packard and Xerox design their products for disassembly. As a result, HP has been able to disassemble and refurbish 12,000 tons of equipment annually with less than 1% waste.

Xerox, a leader in remanufacturing, designs its copiers for multiple lifecycles. Old models can be refurbished or upgraded with new controls, software, and features because the basic form (i.e., rack or frame) and design layout of the machine remains the same. In a discarded copier with 8,000 parts, over 90% can typically be reused. Disassembly is easier because parts are labeled and those that are likely to default or become obsolete at the same time are clustered together. The remanufacturing process involves disassembling and sorting the parts, inspecting them, cleaning them, reprocessing them, then reassembly, final inspection, and testing.

One of the more amazing recycled products on the market is polar fleece, made from recycled soda bottles. But that is not where the journey ends. Patagonia, which makes garments from polar fleece, accepts worn-out fleece, wool, and other garments from its customers and completely recycles them. Discarded garments are cut into bits, pulverized into small pellets, purified, polymerized, melted, and spun into new fabric for new garments, thus completing the cycle in a cradle-to-cradle design. Through its Common Threads recycling program, Patagonia saves 38 million pounds of carbon dioxide emissions each year and creates 20% of its products from post-consumer waste. Read about Nike's recycling and re-use efforts in the "Along the supply Chain" box on the next page.

Whether it's greening a design or making other design changes to please the customer, companies need a procedure for ensuring that the myriad of design decisions are consistent and reflective of customer needs. Such a technique, quality function deployment, is discussed in the next section.

Imagine that two engineers are working on two different components of a car sunroof simultaneously but separately.^[10] The "insulation and sealing" engineer develops a new seal that will keep out rain, even during a blinding rainstorm. The "handles, knobs, and levers" engineer is working on a simpler lever that will make the roof easier to open. The new lever is tested and works well with the old seal. Neither engineer is aware of the activities of the other. As it turns out, the combination of heavier roof (due to the increased insulation) and lighter lever means that the driver can no longer open the sunroof with one hand! Hopefully, the problem will be detected in prototype testing before the car is put into production. At that point, one or both components will need to be redesigned. Otherwise, cars already produced will need to be reworked and cars already sold will have to be recalled. None of these alternatives is pleasant, and they all involve considerable cost.

Coordinating design decisions can be difficult.

ALONG THE SUPPLY CHAIN

Nike's Trash Talking Shoes

Since the launch of its Reuse-A-Shoe program, Nike has recycled more than 21 million pairs of athletic shoes to create public basketball courts, athletic tracks, and playground surfaces around the world. Nike's latest initiative, Considered Design, seeks to design products that use environmentally preferred materials, eliminate toxins, and are fully closed loop (i.e., produced using the fewest possible materials, designed for easy disassembly, and completely recyclable at the end of their useful life or safely returned to nature). One hundred percent compliance to this goal for footwear is expected by 2011, apparel by 2015, and equipment by 2020.

Nike's entry into sustainable practices took an interesting turn when it offered its first line of environmentally friendly shoes. At the center of the line was a walking boot made with brown hemp fibers, dubbed "Air Hobbit" by detractors. From that foray, Nike determined that its customers weren't really interested in being eco-friendly, that they were much more concerned with performance than sustainability. Enter the trash-talking shoe.

Steve Nash, the all-star guard for the Phoenix Suns, forged a partnership with Nike to create a "Nike Trash Talk" version of his favorite basketball shoe. The high-performance shoe is made completely from manufacturing waste—scraps of leather material and foam that would otherwise be discarded, and Nike Grind rubber recycled from old athletic shoes. Although revealed with fanfare at a Suns game, Nike does not, as a rule, market its sustainability efforts. Nike ads do not portray a "feel-good, do-good" attitude; instead, it's all about winning. So Nike prefers to "do more and say less" about its green business practices.

In another effort to go green, the latest design of the Air Jordan eliminates excess plastic, uses recycled material, and is sewn on a newly designed machine that saves electricity and reduces its carbon shoeprint.

1. What types of products do you purchase that are eco-friendly? Are there some products that you would not normally purchase with that designation?

2. How do you feel about purchasing products that are re-manufactured? Should this information be provided in product labels? How do you know that refurbished products or products with recycled content will perform as well as brand new products?

Source: Reena Jana, "Nike Goes Green Very Quietly," BusinessWeek (June 22, 2009), p. 56; Nike Web site, http://www.nikebiz.com/responsibility/considered_design/index.html.

Could such problems be avoided if engineers worked in teams and shared information? Not entirely. Even in design teams, there is no guarantee that all decisions will be coordinated. Ford and Firestone have worked together for over 75 years. But teamwork did not prevent Firestone tires designed to fit the Ford Explorer from failing when inflated to Ford specifications. A formal method is needed for making sure that everyone working on a design project knows the design objectives and is aware of the interrelationships of the various parts of the design. Similar communications are needed to translate the voice of the customer to technical design requirements. Such a process is called quality function deployment (QFD).

• Quality function deployment (QFD): translates the voice of the customer into technical design requirements.

Figure 4.8. Outline of the House of Quality

QFD uses a series of matrix diagrams that resemble connected houses. The first matrix, dubbed the house of quality, converts customer requirements into product-design characteristics. As shown in Figure 4.8, the house of quality has six sections: a customer requirements section, a competitive assessment section, a design characteristics section, a relationship matrix, a tradeoff matrix, and a target values section. Let's see how these sections interrelate by building a house of quality for a steam iron.

Customer requirements

Our customers tell us they want an iron that presses quickly, removes wrinkles, doesn't stick to fabric, provides enough steam, doesn't spot fabric, and doesn't scorch fabric (see Figure 4.9). We enter those attributes into the customer requirements section of the house. For easier reference, we can group them into a category called "Irons well." Next we ask our customers to rate the list of requirements on a scale of 1 to 10, with 10 being the most important. Our customers rate presses quickly and doesn't scorch fabric as the most important attributes, with a score of 9. A second group of attributes, called "Easy and safe to use" is constructed in a similar manner.

Figure 4.9. A Competitive Assessment of Customer Requirements

Figure 4.10. Converting Customer Requirements to Design Characteristics

Next, we conduct a competitive assessment. On a scale of 1 to 5 (with 5 being the highest), customers evaluate our iron (we'll call it "X") against competitor irons, A and B. We see that our iron excels on the customer attributes of presses quickly, removes wrinkles, provides enough steam, automatic shutoff, and doesn't break when dropped. So there is no critical need to improve those factors. However, we are rated poorly on doesn't stick, doesn't spot, heats quickly, quick cool-down, and not too heavy. These are order qualifiers. We need to improve these factors just to be considered for purchase by customers. None of the irons perform well on doesn't scorch fabric, or doesn't burn when touched. Perhaps we could win some orders if we satisfied these requirements.

Competitive assessment

In order to change the product design to better satisfy customer requirements, we need to translate those requirements to measurable design characteristics. We list such characteristics (energy needed to press, weight of iron, size of the soleplate, etc.) across the top of the matrix shown in Figure 4.10. In the body of the matrix, we identify how the design characteristics relate to customer requirements. Relationships can be positive, + or minus, −. Strong relationships are designated with a circled plus,

Tradeoff matrix

Product design characteristics are interrelated also, as shown in the roof of the house in Figure 4.11. For example, increasing the thickness of the soleplate would increase the weight of the iron but decrease the energy needed to press. Also, a thicker soleplate would decrease the flow of water through the holes, and increase the time it takes for the iron to heat up or cool down. Designers must take all these factors into account when determining a final design.

Figure 4.11. The Tradeoff Matrix: Effects of Increasing Soleplate Thickness

Figure 4.12. Targeted Changes in Design

Target values

The last section of the house, shown in Figure 4.12, adds quantitative measures to our design characteristics. Measuring our iron X against competitors A and B, we find that our iron is heavier, larger, and has a thicker soleplate. Also, it takes longer to heat up and cool down, but requires less energy to press and provides more steam than other irons. To decide which design characteristics to change, we compare the estimated impact of the change with the estimated cost. We rate these factors on a common scale, from 1 to 5, with 5 being the most. As long as the estimated impact exceeds the estimated cost, we should make a change. Thus, we need to change several product characteristics in our new design, such as weight of the iron, size of the soleplate, thickness of the soleplate, material used for the soleplate, number of holes, time required to heat up, and time required to cool down.

Figure 4.13. The Completed House of Quality for a Steam Iron

Now visualize a design team discussing target values for these product characteristics using the data provided in the house of quality as a focal point. The house does not tell the team how to change the design, only what characteristics to change. The team decides that the weight of the iron should be reduced to 1.2 lb, the size of the soleplate to 8 in. by 5 in., the thickness of the soleplate to 3 cm, the material used for soleplate to silverstone, the number of holes to 30, time to heat up to 30 seconds, and time to cool down to 500 seconds. Figure 4.13 shows the completed house of quality for the steam iron.

Other houses

The house of quality is the most popular QFD matrix. However, to understand the full power of QFD, we need to consider three other houses that can be linked to the house of quality (Figure 4.14). In our example, suppose we decide to meet the customer requirement of "heats quickly" by reducing the thickness of the soleplate. The second house, parts deployment, examines which component parts are affected by reducing the thickness of the soleplate. Obviously, the soleplate itself is affected, but so are the fasteners used to attach the soleplate to the iron, as well as the depth of the holes and connectors that provide steam. These new part characteristics then become inputs to the third house, process planning. To change the thickness of the soleplate, the dyes used by the metal-stamping machine to produce the plates will have to change, and the stamping machine will require adjustments. Given these changes, a fourth house, operating requirements, prescribes how the fixtures and gauges for the stamping machine will be set, what additional training the operator of the machine needs, and how process control and preventive maintenance procedures need to be adjusted. Nothing is left to chance—all bases are covered from customer to design to manufacturing.

Figure 4.14. A Series of Connected QFD Houses

In comparison with traditional design approaches, QFD forces management to spend more time defining the new product changes and examining the ramifications of those changes. More time spent in the early stages of design means less time is required later to revise the design and make it work. This reallocation of time shortens the design process considerably. Some experts suggest that QFD can produce better product designs in half the time of conventional design processes. In summary, QFD is a communications and planning tool that promotes better understanding of customer demands, promotes better understanding of design interactions, involves manufacturing in the design process, and provides documentation of the design process.

Benefits of QFD

A product can fail because it was manufactured wrong in the factory—quality of conformance—or because it was designed incorrectly—quality of design. Quality-control techniques, such as statistical process control (SPC) discussed in Chapter 3, concentrate on quality of conformance. Genichi Taguchi, a Japanese industrialist and statistician, suggests that product failure is primarily a function of design quality.

Consumers subject products to an extreme range of operating conditions and still expect them to function normally. The steering and brakes of a car, for example, should continue to perform their function even on wet, winding roads or when the tires are not inflated properly. A product designed to withstand variations in environmental and operating conditions is said to be robust or to possess robust quality. Taguchi believes that superior quality is derived from products that are more robust and that robust products come from robust design.

Robust design: yields a product or service designed to withstand variations.

The conditions that cause a product to operate poorly can be separated into controllable and uncontrollable factors. From a designer's point of view, the controllable factors are design parameters such as material used, dimensions, and form of processing. Uncontrollable factors are under the user's control (length of use, maintenance, settings, and so on). The designer's job is to choose values for the controllable variables that react in a robust fashion to the possible occurrences of uncontrollable factors. To do this, various configurations of the product are tested under different operating conditions specified in the design of experiments (DOE). The experiment is replicated multiple times. The mean performance of an experimental configuration over a number of trials is called the "signal." The standard deviation of performance is referred to as "noise." The most robust design exhibits the highest signal-to-noise ratio.

The signal-to-noise ratio measures the robustness of a design.

• Tolerances: allowable ranges of variation.

As part of the design process, design engineers must also specify certain tolerances, or allowable ranges of variation in the dimension of a part. It is assumed that producing parts within those tolerance limits will result in a quality product. Taguchi, however, suggests that consistency is more important to quality than being within tolerances. He supports this view with the following observations.

Let's examine each of these observations.

Consistency is important to quality.

Consistent mistakes are easier to correct. Consider the professor who always starts class 5 minutes late. Students can adjust their arrival patterns to coincide with the professor's, or the professor's clock can be set ahead by 5 minutes. But if the professor sometimes starts class a few minutes early, sometimes on time, and other times 10 minutes late, the students are more apt to be frustrated, and the professor's behavior will be more difficult to change.

Consistency is especially important for assembled products. The assembly of two parts that are near opposite tolerance limits may result in tolerance stack-ups and poor quality. For example, a button diameter that is small (near to the lower tolerance limit) combined with a buttonhole that is large (near to its upper tolerance limit) results in a button that won't stay fastened. Although it is beyond the scope of this book, Taguchi advises how to set tolerance limits so that tolerance stack-up can be avoided.

Manufacturing tolerances define what is acceptable or unacceptable quality. Parts or products measured outside tolerance limits are considered defective and are either reworked or discarded. Parts or products within the limits are considered "good." Taguchi asserts that although all the parts or products within tolerances may be acceptable, they are not all of the same quality. Consider a student who earns an average grade of 60 in a course. He or she will pass, whereas a student who earns an average grade of 59 will fail. A student with a 95 average will also pass the course. Taguchi would claim that there is negligible difference between the quality of the students with averages of 59 and 60, even though one was "rejected" and the other was not. There is, however, a great deal of difference in the quality of the student with an average of 60 and the student with an average of 95. Furthermore, a professor in a subsequent class or a prospective employer will be able to detect the difference in quality and will overwhelmingly prefer the student who passed the course with a 95 average. Quality near the target value is preferable to quality that simply conforms to specifications.

The quality loss function quantifies customer preferences toward quality.

Taguchi quantified customer preferences toward on-target quality in the quality loss function (QLF). The quadratic function, graphed in Figure 4.15 implies that a customer's dissatisfaction (or quality loss) increases geometrically as the actual value deviates from the target value. The quality loss function is used to emphasize that customer preferences are strongly oriented toward consistently meeting quality expectations. Design for Six Sigma (DFSS) uses the Taguchi method to reduce variability in design.

Figure 4.15. Taguchi's Quality Loss Function

New products and services enhance a company's image, invigorate employees, and help a firm to grow and prosper. The design process begins with ideas formulated into a product concept. Once a product concept passes a feasibility study, performance specs are given to designers who develop and test prototype designs. For selected prototypes, design and manufacturing specs are taken through a pilot run where the design is finalized and the planning for product launch begins.

Time-to-market can be accelerated by using design teams, concurrent design, design for manufacture concepts, and CAD/CAM systems. The quality of design can be improved through design reviews, design for environment, quality function deployment, and robust design.

benchmarking finding the best-in-class product or process, measuring one's performance against it, and making recommendations for improvements based on the results.

carbon footprint a measure of the greenhouse gases produced by an activity, product or company

collaborative product design (CPD) software system for collaborative design and development among trading partners.

computer-aided design (CAD) a software system that uses computer graphics to assist in the creation, modification, and analysis of a design.

computer-aided design/computer-aided manufacturing (CAD/CAM) the ultimate design-to-manufacture connection.

computer-aided engineering (CAE) engineering analysis performed at a computer terminal with information from a CAD database.

concurrent design a new approach to design that involves the simultaneous design of products and processes by design teams.

design for environment (DFE) designing a product from material that can be recycled or easily repaired rather than discarded.

design for manufacture (DFM) designing a product so that it can be produced easily and economically.

eco-labeling a seal of approval for environmentally safe products

extended producer responsibility (EPR) holding a company responsible for its product even after its useful life.

failure mode and effects analysis (FMEA) a systematic approach to analyzing the causes and effects of product failures.

fault tree analysis (FTA) a visual method for analyzing the interrelationships among failures.

form design the phase of product design concerned with how the product looks.

functional design the phase of a product design concerned with how the product performs.

maintainability the ease with which a product is maintained or repaired.

modular design combining standardized building blocks, or modules, in a variety of ways to create unique finished products.

perceptual map visual method for comparing customer perceptions of different products or services.

production design the phase of product design concerned with how the product will be produced.

product lifecycle management (PLM) software for managing the entire lifecycle of a product.

quality function deployment (QFD) a structured process that translates the voice of the customer into technical design requirements.

rapid prototyping quickly testing and revising a preliminary design model.

reliability the probability that a given part or product will perform its intended function for a specified period of time under normal conditions of use.

reverse engineering carefully dismantling and inspecting a competitor's product to look for design features that can be incorporated into your own product.

robust design the design of a product or a service that can withstand variations in environmental and operating conditions.

simplification reducing the number of parts, subassemblies, or options in a product.

standardization using commonly available parts that are interchangeable among products.

sustainability the ability to meet present needs without jeopardizing the needs of future generations.

tolerances allowable ranges of variation.

usability ease of use of a product or service.

value analysis (VA) an analytical approach for eliminating unnecessary design features and functions.

Reliability in series

R_s = (R₁)(R₂) . . . (R_n)

Reliability in parallel

R_s = R₁ + (1 – R₁)R₂)

or

R_s = 1 – [(1 – R₁)(1 – R₂) . . . (1 – R_n)]

Mean time between failures

System availability

1. RELIABILITY

Jack McP hee, a production supervisor for McCormick, Inc., is committed to the company's new quality efforts. Part of the program encourages making product components in-house to ensure higher quality levels and instill worker pride. The system seems to be working well. One assembly, which requires a reliability of 0.95, is normally purchased from a local supplier. Now it is being assembled in-house from three components that each boast a reliability of 0.96.

SOLUTION

2. SYSTEM AVAILABILITY

Amanda is trying to decide which Internet service provider to use. Her friends are always complaining about service interruptions and how long it takes to get the service up and running again. Amanda is a conscientious student and wants reliable access to the Internet. With that goal in mind, she has collected data on mean time between failures (MTBF) and mean time to repair (MTTR) for three Internet service providers. Given that cost and speed are comparable among the three options, which provider would you recommend?

SOLUTION

Choose MostTel

• Weblinks

4-1. Describe the strategic significance of design. How can organizations gain a competitive edge with product or service design?

4-2. Look around your classroom and make a list of items that impede your ability to learn. Classify them as problems in quality of design or quality of conformance.

4-3. Give an example of a product or service you have encountered that was poorly designed. Read about more bad designs at the bad designs Web site http://www.baddesigns.com. Make a list of the factors that make a design unworkable.

4-4. Sometimes failures provide the best opportunities for new products and services. Read the Post-It Note story at http://www.3m.com. Search the Net for at least one other failure-to-success story.

4-5. BusinessWeek sponsors a best design competition each year. Read about this year's winners and write a brief summary about what makes these designs special.

4-6. Automakers often post concept cars on their Web sites. Find out how the design process for these cars differs. Which cars do you think will be commercially successful? Why?

4-7. Construct a perceptual map for the following products or services: (a) business schools in your state or region, (b) software packages, and (c) video rental stores. Label the axes with the dimensions you feel are most relevant. Explain how perceptual maps are used.

4-8. Read about benchmarking at the American Productivity and Quality Center http://www.apqc.org and the Benchmarking Exchange http://www.benchnet.com. What is benchmarking? What types of things do these organizations benchmark? How are the studies conducted? If possible, access one of the free benchmarking reports and summarize its findings.

4-9. Find out if your university benchmarks itself against other universities. If so, write a summary of the characteristics that are considered, the measures that are used, and the results. Do the data support your views as a customer?

4-10. What kinds of analyses are conducted in a feasibility study for new products?

4-11. Differentiate between performance specifications, design specifications, and manufacturing specifications. Write sample specifications for a product or service of your choosing.

4-12. How are reliability and maintainability related? Give an example for a product or service you have experienced.

4-13. Explain how simplification and standardization can improve designs. How does modular design differ from standardization?

4-14. How can design teams improve the quality of design? Relate your experiences in working in teams. What were the advantages and disadvantages?

4-15. Discuss the concept of concurrent design. What are the advantages of this approach? How would you apply concurrent design to a group project?

4-16. What does design for manufacture entail? List several techniques that can facilitate the DFM process.

4-17. Describe the objectives of failure mode and effect analysis, fault tree analysis, and value analysis. Apply one of the techniques to a project, computer assignment, or writing assignment you have recently completed.

4-18. Access the Environmental Protection Agency http://www.epa.gov/ to read about the U.S. government's commitment to environmental product design. Compare the U.S. approach to that of other countries.

4-19. Search the Internet for two or more companies that design for environment. What are the main components of each company's green design initiative? How do their approaches differ?

4-20. Link to the International Standards Organization http://www.iso.org and explore ISO 14000. What do these standards entail? How were they developed? How does a company attain ISO 14001 certification? Why would they want to?

4-21. What is the purpose of QFD? Find out if companies really use QFD by visiting the QFD Institute http://www.qfdi.org and summarizing one of their case studies.

4-22. Discuss the concept of robust design. Give an example of a robust product or service.

4-23. How does CAD relate to CAE and CAM? How do CAD and the Internet promote collaborative design?

4-1. Use the following instructions to construct and test a prototype paper airplane. Are the instructions clear? How would you improve the design of the airplane or the manner in which the design is communicated?

4-2. An alternative airplane design is given here. Follow the assembly instructions and test the airplane. Are the instructions clear? Compare the performance of this airplane design with the one described in Problem 4.1. Which plane was easier to construct? How would you improve the design of this plane or the manner in which the design is communicated?

4-3. Calculate the reliability of the following system.

4-4. A broadcasting station has five major subsystems that must all be operational before a show can go on the air. If each subsystem has the same reliability, what reliability would be required to be 95% certain of broadcast success? 98% certain? 99% certain?

4-5. Competition for a new generation of computers is so intense that MicroTech has funded three separate design teams to create the new systems. Due to varying capabilities of the team members, it is estimated that team A has a 90% probability of coming up with an acceptable design before the competition, team B has an 80% chance, and team C has a 70% chance. What is the probability that MicroTech will beat the competition with its new computers?

4-6. MagTech assembles tape players from four major components arranged as follows:

The components can be purchased from three different vendors, who have supplied the following reliability data:

4-7. Glen Evans is an emergency medical technician for a local rescue team and is routinely called on to render emergency care to citizens facing crisis situations. Although Glen has received extensive training, he also relies heavily on his equipment for support. During a normal call, Glen uses five essential pieces of equipment, whose individual reliabilities are 0.98, 0.97, 0.95, 0.96, and 0.99, respectively.

4-8. Examine the systems given below. Which system is more reliable, a or b? c or d? Now calculate the reliability of each system. Were your perceptions correct?

If it costs $1000 for each 90% reliable component, $1500 for each 93% component, $2000 for each 95% reliable component, and $10,000 to replace a failed system, which system would you choose, a or b? c or d?

4-9. Omar Marquez is the audio engineer for Summer Musical Enterprises. The group is considering the purchase of a new sound system consisting of five separate components. The components are arranged in series with identical reliabilities. The Basic system with component reliabilities of 80% costs $1000, the Standard system with component reliabilities of 90% costs $2000, and the Professional system with component reliabilities of 99% costs $5000. The cost of a failure during a performance is $50,000.

4-10. La Pied manufactures high-quality orthopedic shoes. Over the past five years, the general public has "found" La Pied products, and sales have skyrocketed. One unanticipated result has been a sharp increase in factory returns for repair, since local shoe repair shops do not have the materials or expertise to fix La Pied products. The popular walking sandal has been targeted for redesign. Currently, the leather pieces are glued together, then stitched. There is a 70% chance that the glue will last for the life of the sandal, and a 50% chance that the stitching will remain intact. Determine the sandal's reliability. How would the reliability of the sandal increase if the company adds two more rows of stitching?

4-11. The Management Department recently purchased a small copier for faculty use. Although the workload of the office staff has improved somewhat, the secretaries are still making too many trips to the Dean's office when the departmental copier is out of service. Sylvia, the departmental secretary, has been keeping track of failure rates and service times. With a mean time between failures of 100 hours and a mean time to repair of 24 hours, how much of the time is the new copier available for faculty use?

4-12. Karen Perez runs an office supply store that also performs simple office services, such as copying. It is time to purchase a new high-speed copier and Karen has learned that machine uptime is a critical factor in selection. She has gathered the following data on reliability and maintainability for the three copiers she is considering. Given that all other factors are equal, which machine should Karen purchase?

4-13. As a regional sales manager, Nora Burke travels frequently and relies on her cell phone to keep up to date with clients. She has tried three different service providers, Airway, Bellular, and CyCom, with varying degrees of success. The number of failures in a typical eight-hour day and the average time to regain service are shown below. Nora's contract is up for renewal. Which cellular service should she use?

4-14. Nadia Algar is the overworked IT resource person for her department. In the next round of computer purchases, she is determined to recommend a vendor who does a better job of documenting possible errors in the system and whose customer service line is more responsive to the needs of her colleagues. Nadia compiled the following data over an eight-week observation period. Assuming 40 hours per week, which computer vendor should Nadia pursue?

4-15. As manager of The Fitness Center, Dana is constantly trying new initiatives to keep her clients fit. Recent studies show that using several different cardio regimens for short periods of time is more effective than an extended period of time on one type of equipment. Dana has taken some of the existing cardio equipment and arranged them in a line as follows: stationary bike, treadmill, stair stepper. Clients would select this part of the gym for cardio "circuit training," spending 15 minutes at each piece of equipment for a total cardio workout time of 45 minutes.

4-16. Derek is disappointed in his high-speed Internet service. Although the Internet is seldom down, it kicks into slow mode quite often, which Derek considers to be a failure. He has tried three service providers with varying degrees of success. The number of failures in a typical eight-hour day and the average time to regain high-speed service are shown below. Derek must choose one of the following options. Calculate the system availability for each option. Which service would you recommend?

4-17. The PlayBetter Golf Company has experienced a steady decline in sales of golf bags over the past five years. The basic golf bag design has not changed over that period, and Play Better's CEO, Jack Palmer, has decided that the time has come for a customer-focused overhaul of the product. Jack read about a new design method called QFD in one of his professional magazines (it was used to design golf balls), and he commissioned a customer survey to provide data for the design process. Customers considered the following requirements essential for any golf bag they would purchase and rated PlayBetter's bag (X) against two competitor bags (A and B) on those requirements.

Construct a house of quality for golf bags. Then write a brief report to Mr. Palmer recommending revisions to the current golf bag design and explaining how those recommendations were determined.

4-18. Students often complain that the requirements of assignments or projects are unclear. From the student's perspective, whoever can guess what the professor wants wins the highest grade. Thus, grades appear to be assigned somewhat arbitrarily. If you have ever felt that way, here is your chance to clarify that next project or assignment.

Construct a house of quality for a paper or project. View the professor as the customer. For the perceptual map, have your professor compare one of your papers with typical A, B, or C papers. When you have completed the exercise, give your opinion on the usefulness of QFD for this application.

4-19. Create a house of quality for a computer. Develop customer requirements related to ease of use, cost, capabilities, and connectivity. Make sure the customer requirements are a "wish list" stated in nontechnical terms.

4-20. Create a QFD example from your own experience. Describe the product or service to be designed and then complete a house of quality using representative data. Explain the entries in the house and how target values were reached. Also, describe how other houses might flow from the initial house you built. Finally, relate how QFD improves the design process for the example you chose.

Greening Product Design

Hal Parker was not convinced that customers cared about green design. "Sure, if it reduces their power consumption, they care, but using less resources to produce the product or using recycled raw materials to begin with? I think our efforts are wasted there."

"But doesn't that save us money in the long run?" commented Sasha Minolta, the finance director.

"If we're in business that long to reap the benefits," Hal retorted. "A recession is not the time to go green."

"Why are you fighting this?" Alex Verera, the CEO, questioned. "Just redesign us a sustainable product and be done with it!"

"That's my point," Hal replied. "Just change the product platform, the basic materials used, the tooling, the operating requirements, the power source, the supplier specs, the quality standards, the production runs, the warranties and take-back conditions, and toss in untested new technology with a product that won't have the feel and performance of the previous version . . . all to say we are green, too. Let's make sure this is really what we want to do. I need some guidance here."

Lean and Mean

Megan McNeil, product manager for Lean and Mean (L&M) weight reduction company, is considering offering its own brand of prepared dinners to its clients. Clients would order the dinners, usually a month's supply at a time, from L&M's Web site and have them delivered to their home address. The dinners would, of course, encourage weight loss, but would also be more nutritious, tastier, and easier to prepare than current grocery store offerings. The price would most likely be on the high end of the scale.

The product design team has constructed the framework for a house of quality from initial customer interviews. Now the team is set to perform a competitive assessment by selecting three popular grocery store brands and measuring the design characteristics. As the team works on the house, it is anticipated that additional design characteristics may emerge. The target row of the house would represent L&M's new brand.

Complete the following house of quality, and write a report to Megan containing your recommendations for the new product development. Be sure to explain how you arrived at your conclusions.

Baldwin, C., and K. Clark. Design Rules: The Power of Modularity. Boston: MIT Press, 2000.

Blackburn, J. (ed.). Time-Based Competition: The Next Battleground. Homewood, IL: Irwin, 1991.

Bowen, H. K., K. Clark, and C. Holloway. The Perpetual Enterprise Machine. New York: Oxford University Press, 1994.

Goleman, Daniel. Ecological Intelligence. New York: Broadway Books, 2009.

Hawkens, Paul. The Ecology of Commerce. New York: Harper Collins, 1994.

Hauser, J. R., and D. Clausing. "The House of Quality." Harvard Business Review (May–June 1988), pp. 63–73.

Kelley, T., Jonathan Littman, and Tom Peters, The Art of Innovation: Lessons in Creativity from IDEO. New York: Currency/Doubleday, 2001.

King, B. Better Designs in Half the Time. Methuen, MA: GOAL/QPC, 1989.

Leonard-Barton, D. Wellsprings of Knowledge: Building and Sustaining the Sources of Innovation. Boston: Harvard Business School Press, 1995.

McDonough, William, and Michael Braungart, Cradle to Cradle, New York: North Point Press. 2002.

Nidumolu, Ram, C. K. Prahlad, and M. R. Rangaswami, "Why Sustainability is Now the Key Driver for Innovation." Harvard Business Review(September 2009).

Stoll, H. "Design for Manufacture." Manufacturing Engineering (January 1988), pp. 67–73.

Sullivan, L. P. "Quality Function Deployment." Quality Progress 19 (6; 1986), p. 39.

Taguchi, G., and D. Clausing. "Robust Quality." Harvard Business Review (January–February 1990), pp. 65–75.

Unruh, Gregory. "The Biosphere Rules," Harvard Business Review (February 2008).

Whitney, D. "Manufacturing by Design." Harvard Business Review (July–August 1988), pp. 83–91.

Womack, J. P., D. T. Jones, and D. Roos. The Machine that Changed the World. New York: Macmillan, 1990.