PRODUCT DESIGN !

Product design is cross-functional, knowledge-intensive work that has become increasingly important in today's fast-paced, globally competitive environment. It is a key strategic activity in many firms because new products contribute significantly to sales revenue. When firms are able to develop distinctive products, they have opportunities to command premium pricing. Product design is a critical factor in organizational success because it sets the characteristics, features, and performance of the service or good that consumers demand.

The objective of product design is to create a good or service with excellent functional utility and sales appeal at an acceptable cost and within a reasonable time. The product should be produced using high-quality, low-cost materials and methods. It should be produced on equipment that is or will be available when production begins. The resulting product should be competitive with or better than similar products on the market in terms of quality, appearance, performance, service life, and price.

THE INCREASING IMPORTANCE OF PRODUCT DESIGN

Product design is more important than ever because customers are demanding greater product variety and are switching more quickly to products with state-of-the-art technology. The impacts of greater product variety and shorter product life cycles have a multiplicative effect on the number of new products and derivative products that need to be designed. For example, just a few years ago, a firm may have produced four different products and each product may have had a product life cycle of ten years. In this case, the firm must design four new products every ten years.

Today, in order to be competitive, this firm may produce eight different products with a life cycle of only five years; this firm must introduce eight new products in five years. That represents sixteen new products in ten years or one product every seven and one-half months. In this fast-paced environment, product design ceases to be an ad hoc, intermittent activity and becomes a regular and routine action. For an organization, delays, problems, and confusion in product design shift from being an annoyance to being life threatening.

PRODUCT DESIGN AND SUPPLY CHAIN MANAGEMENT

Product design can also be an important mechanism for coordinating the activities of key supply chain participants. As organizations outsource the production of sub-assemblies and components, they also may be asking suppliers to participate in product design. As they outsource design capabilities it is essential that they manage and coordinate the flow of information among the supply chain participants.

This can be especially important as firms outsource components to two or more suppliers. Now, there may be important design interfaces among two, three, or more suppliers. These interfaces must be properly managed to ensure cost effective and timely designs. Clearly, information and communication technologies become important parts of this effort.

PRODUCT DESIGN: A KEYTO ORGANIZATIONAL SUCCESS

Product design is an essential activity for firms competing in a global environment. Product design drives organizational success because it directly and significantly impacts nearly all of the critical determinants for success. Customers demand greater product variety and are quick to shift to new, innovative, full-featured products. In addition, customers make purchase decisions based on a growing list of factors that are affected by product design. Previously, customers made purchase decisions based primarily on product price and/or quality. While these factors are still important, customers are adding other dimensions such as customizability, order-to-delivery time, product safety, and ease and cost of maintenance.

Environmental concerns are expanding to include impacts during production, during the product's operating life, and at the end of its life (recycle-ability). In addition, customers demand greater protection from defective products, which leads to lower product liability losses. Safer and longer lasting products lead to enhanced warrantee provision, which, in turn, impact customer satisfaction and warrantee repair costs.

Programs and activities are being put in place so organizations can cope with these dimensions. Organizations are embracing concepts such as mass customization, design for manufacturing and assembly, product disposal, quality function deployment, and time-based competition. They are using technology such as rapid prototyping and computer-aided design to examine how products function, how much they may cost to produce, and how they may impact the environment. Firms are searching for and implementing new technologies to determine ways to design better products. They are examining legal and ethical issues in product design as well as the impact of product design on the environment.

MASS CUSTOMIZATION

Mass customization is the low-cost, high-quality, large volume delivery of individually customized products. It is the ability to quickly design and produce customized products on a large scale at a cost comparable to non-customized products. Customization, cost effectiveness is the ability to produce highly differentiated products without increasing costs, significantly. Consumers expect to receive customized products at close to mass-production prices.

Customization volume effectiveness is the ability to increase product variety without diminishing production volume. As markets become more and more segmented and aggregate demand remains constant or increases, firms must continue to design and produce high volumes across the same fixed asset base.

Customization responsiveness is the ability to reduce the time required to deliver customized products and to reorganize design and production processes quickly in response to customer requests. It would be counter-productive to pursue mass customization if a customized product takes too long to produce. Speed in product design and production is an indispensable criterion for evaluating an organization's mass customization capability.

DESIGN FOR MANUFACTURING AND ASSEMBLY

Improving manufacturability is an important goal for product design. A systems approach to product design that was developed by two researchers from England, Geoffrey Boothroyd and Peter Dewhurst, is called design for manufacturability and assembly (DFMA). It can be a powerful tool to improve product quality and lower manufacturing cost. The approach focuses on manufacturing issues during product design.

DFMA is implemented through computer software that identifies designs concepts that would be easy to build by focusing on the economic implications of design decisions. These decisions are critical even though design is a small part of the overall cost of a product because design decisions fix 70 to 90 percent of the manufacturing costs. In application, DFMA has had some startling successes. With the DFMA software, Texas Instruments reduced assembly time for an infrared sighting mechanism from 129 minutes to 20 minutes. IBM sliced assembly time for its printers from thirty minutes to three minutes.

Firms are recognizing that the concept behind DFMA can also be extended beyond cost control to design products that are easy to service and maintain. To do this effectively, service and maintenance issues should be considered at the earliest stages of the design. Also, firms will be required to examine disposal during product design as they become liable for recycling the products they make. It can be easier to recycle products if those factors are part of the product design paradigm.

DISPOSAL AND PRODUCT DESIGN

Disposal is becoming an increasingly important part of product design. The European Union is taking the lead by requiring that most of an automobile is recycled by the year 2010. This requirement has a major impact on product design. The most obvious effect is to change the notion that a consumer is the final owner for a product. With this approach, the product returns to the manufacturer to be recycled and the recycling process should begin in product design.

Vehicles should be designed so they can be disassembled and recycled easily. The designers should avoid exotic materials that are difficulty to recycle. For example, parts that have plastic and metal fused together should not be used in applications where they are difficult to separate. The designers should determine which parts will be designed to be refurbished and reused, and which will be designed to be discarded, broken down, and recycled. All this should be done without adding costs or reducing product quality.

QUALITY AND QUALITY FUNCTION DEPLOYMENT

Product design shapes the product's quality. It defines the way that good and service functions. Quality has at least two components. First, the product must be designed to function with a high probability of success, or reliability; that is, it will perform a specific function without failure under given conditions. When product reliability increases, the firm can extend the product's warrantee without increasing customer claims for repairs or returns.

Warrantees for complex and expensive items such as appliances are important selling points for customers. Second, quality improves when operating or performance characteristics improve even though reliability does not. The goals of product design should be greater performance, greater reliability, and lower total production and operating costs. Quality and costs should not be viewed as a trade-off because improvements in product and process technologies can enhance quality and lower costs.

Quality function deployment is being used by organizations to translate customer wants into working products. Sometimes referred to as the house of quality, quality function deployment (QFD) is a set of planning and communication routines that focus and coordinate actions and skills within an organization. The foundation of the house of quality is the belief that a product should be designed to reflect customers' desires and tastes. The house of quality is a framework that provides the means for inter-functional planning and communications. Through this framework, people facing different problems and responsibilities can discuss various design priorities.

PROTOTYPING

Engineering and operations combine to develop models of products called prototypes. These may be working models, models reduced in scale, or mock-ups of the products. Where traditional prototype development often takes weeks or months, the technology for rapid prototyping has become available. Some companies are using the same technology that creates virtual reality to develop three-dimensional prototypes. Other firms employ lasers to make prototypes by solidifying plastic in only a few minutes; this process can produce prototypes with complex shapes. Prototyping should increase customer satisfaction and improve design stability, product effectiveness, and the predictability of final product cost and performance.

COMPUTER-AIDED DESIGN

Currently, business managers and engineers perceive computer-aided design (CAD) as a tool to assist engineers in designing goods. CAD uses computer technology and a graphic display to represent physical shapes in the same way that engineering drawings have in the past. It is used in the metalworking industry to display component parts, to illustrate size and shape, to show possible relationships to other parts, and to indicate component deformation under specified loads. After the design has been completed, the engineer can examine many different views or sections of the part and finally send it to a plotter to prepare drawings.

This capability greatly reduces engineering time and avoids routine mistakes made in analysis and drawing. It significantly increases productivity and reduces design time, which allows faster delivery. Applications of CAD systems are not limited to producing goods. While it's true that services do not have physical dimensions, the equipment and facilities used to produce services do. For example, the service stalls in an automotive center or rooms in an emergency medical center have physical characteristics that can be represented by the interactive graphics capabilities of a CAD system.

LEGAL AND ETHICAL ISSUES IN PRODUCT DESIGN

What is the responsibility of an organization and its managers to see that the goods and services they produce do not harm consumers? Legally, it is very clear that organizations are responsible for the design and safe use of their products. Consumers who believe they have been damaged by a poorly designed good or service have legal recourse under both civil and criminal statutes. Often, however, only the most serious and obvious offenses are settled in this way. More difficult ethical issues in product design result when the evidence is not as clear.

For example, what responsibilities does a power tool manufacturer have with respect to product safety? Does a power saw manufacturer have the responsibility to design its product so that it is difficult for a child to operate? Suppose a parent is using a power saw and is called away to the telephone for a few minutes. A ten-year old may wander over, press the trigger and be seriously injured. Designing the saw so it has a simple and inexpensive lockout switch that would have to be pressed simultaneously when the trigger is pressed would make it more difficult for the accident to happen. What is the responsibility of the parent? What is the responsibility of the company?

PRODUCT DESIGN AND THE ENVIRONMENT

Organizations consider product design a critical activity to the production of environmentally friendly products. Organizations increasingly recognize that being good corporate citizens increases sales. Fast-food restaurants have begun recycling programs and redesigned packaging materials and systems in response to customer concerns. In other cases, being a good corporate citizen and protecting a company's renewable resources go well together; there are win-win opportunities where an organization can actually design products and processes that cut costs and increase profits by recapturing pollutants and reducing solid waste.

OVERVIEW OF PRODUCT DESIGN PROCESS

Product design time can be reduced by using a team approach and the early involvement of key participants including marketing, research and development, engineering, operations, and suppliers. Early involvement is an approach to managing people and processes. It involves an upstream investment in time that facilitates the identification and solution of down-stream problems that would otherwise increase product design and production costs, decrease quality, and delay product introduction.

Time-based competitors are discovering that reducing product design time improves the productivity of product design teams. To reduce time, firms are reorganizing product design from an "over-the-wall" process to a team-based concurrent process. Over-the-wall means to proceed sequentially with the limited exchange of information and ideas. When this approach is used, problems are often discovered late because late-stage participants are excluded from decisions made early in the process. As a result, poor decisions are often made.

Product design is a labor-intensive process that requires the contribution of highly trained specialists. By using teams of specialists, communications are enhanced, wait time between decisions is reduced, and productivity is improved. Participants in this team-based process make better decisions faster because they are building a shared knowledge base that enhances learning and eases decision-making. By sharing development activities, design decisions that involve interdependencies between functional specialists can be made more quickly and more effectively. This reorganized process creates a timely response to customer needs, a more cost-effective product design process, and higher-quality products at an affordable price.

There are several reasons why early involvement and concurrent activities bring about these improvements. First, product design shifts from sequential, with feedback loops that occur whenever a problem is encountered, to concurrent, where problems are recognized early and resolved. The ability to overlap activities reduces product design time. Second, when a team of functional specialists works concurrently on product design, the participants learn from each other and their knowledge base expands. People are better able to anticipate conflicts and can more easily arrive at solutions. As a result, the time it takes to complete an activity should decline. Third, fewer changes later in the process results in faster and less expensive product design. When problems are discovered late, they take more time and money to solve.

Product design requires the expertise and decision-making skills of all parts of the organization. Marketing, engineering, operations, finance, accounting, and information systems all have important roles. Marketing's role is to evaluate consumer needs, determine potential impact of competitive pressure, and measure the external environment. Engineering's role is to shape the product through design, determine the process by which the product will be made, and consider the interface between the product and the people.

Operations' role is to ensure that the product can be produced in full-scale production. Finance's role is to develop plans for raising the capital to support the product in full-scale production and to assist in the evaluation of the product's profit potential. Accounting and information systems provide access to information for decision making. Cross-functional teamwork and knowledge sharing are thus keys to success.

FURTHER READING:

Corswant, F, and C. Tunälv. "Coordinating Customers and Proactive Suppliers: A Case Study of Supplier Collaboration in Product Development." Journal of Engineering and Technology Management 19, no. 3-4 (2002): 249–261.
Droge, C., J. Jayaram, and S. Vickery. "The Ability to Minimize the Timing of
New Product Development and Introduction: An Examination of Antecedent
Factors in the North American Automobile Supplier Industry." Journal of Product Innovation Management 17 (2000): 24–40.
Gerwin, D., and N.J. Barrowman. "An Evaluation of Research on Integrated Product Development." Management Science 48, no. 7 (2002): 938–953.
Hong, S.K., and M.J. Schniederjans. "Balancing Concurrent Engineering Environmental Factors for Improved Product Development Performance." International Journal of Production Research 38, no. 8 (2000): 1779–1800.
Koufteros, X.A., M. Vonderembse, and J. Jayaram. "Internal and External Integration for Product Development: The Contingency Effects of Uncertainty, Equivocality, and Platform Strategy." Decisions Sciences 36, no. 1 (2005): 977–133.
Koufteros, X.A., M. Vonderembse, and W. Doll. "Concurrent Engineering and Its Consequences." Journal of Operations Management 19 (2001): 97–115.
Krishnan, V., and K.T. Ulrich. "Product Development Decisions: A Review of the Literature." Management Science 47, no. 1 (2001): 1–21.
McDermott, C.M., and G.C. O'Connor. "Managing Radical Innovation: An Overview of Emergent Strategy Issues." Journal of Product Innovation Management 19, no. 6 (2002): 424–438.
Meyer, M.H., and A.P. Lehnerd. The Power of Product Platforms. New York: The Free Press.
Reinertsen, D.G. Managing the Design Factory. New York: The Free Press.
Song, X. M., and M. Montoya-Weiss. "The Effect of Perceived Technological Uncertainty on Japanese New Product Development." Academy of Management Journal 44 (2001): 61–80.
Tu, Q., M. Vonderembse, and T.S. Ragu-Nathan. "The Impact of Time-Based Manufacturing Practices on Mass Customization and Value to Customer." Journal of Operations Management 19 (2001): 201–217.
Vonderembse, M.A., and G.P. White. Operations Management: Concepts, Methods, and Strategies. Danvers, MA: John Wiley & Sons, 2004.

Prepared by:
Putra-Design
Bandar Puncak Alam,
Malaysia.

POKA-YOKE !

Poka-yoke is a technique for avoiding simple human error in the workplace. Also known as mistake-proofing, goof-proofing, and fail-safe work methods, poka-yoke is simply a system designed to prevent inadvertent errors made by workers performing a process. The idea is to take over repetitive tasks that rely on memory or vigilance and guard against any lapses in focus. Poka-yoke can be seen as one of the three common components of Zero Defect Quality Control performed by Japanese companies (source inspection and feedback are the other two).

Dr. Shigeo Shingo, a renowned authority on quality control and efficiency, originally developed the mistake-proofing idea. Realizing its value as an effective quality control technique, he formalized its use in Japanese manufacturing as the poka-yoke system. One hundred percent inspections catch unacceptable products but do nothing to improve the process. Shingo was emphatic that the purpose of this system be to improve the process not sort out defective parts.

Today, this concept is in wide use in Japan. Toyota Motor Corporation, whose production system Shingo helped design, averages twelve poka-yoke devices per machine in their manufacturing plants, thus validating the concept as beneficial to industry. Patel, Dale, and Shaw, in the article "Set-Up Time Reduction and Mistake Proofing Methods: An Examination in Precision" list the potential benefits as:

• elimination of set-up errors and improved quality .
• decreased set-up times with associated reduction in production time and improved
• production capacity .
• simplified and improved housekeeping.
• increased safety.
• lower costs .
• lower skill requirements.
• increased production flexibility .
• improved operator attitudes.

In a Quality magazine article, Melissa Larson provides interesting details about benefits resulting from the implementation of poka-yoke systems at the Supply Support Activity (SSA) at Fort Carson, Colorado, a military retail supply operation of the U.S. Army.
Inventory, receipt, and batch processing all improved quantifiably. Location survey accuracy was approximately sixty-five percent prior to implementation.

After implementing the use of the bar-code readers location accuracy increased
to ninety-eight percent. Inventory adjustments averaged $3000 a month. Inventory adjustments dropped to an average of $250 per month. The rate of incorrect receipt closures to the supplier had been ninety percent. This rate dropped to zero percent. Batch processing was also significantly improved.

Traditionally, the SSA had approximately fifteen to twenty batch processing failures per month, and a myriad of system file failures due to operators performing the process out of proper sequence. Since the poka-yoke implementations, there have been zero batch process failures.
Catalog update improvements also resulted. The error rate was twenty-two percent but dropped to zero percent. Original request processing time was 12.5 days, but with the new request processing time is 1.6 days. Actual dollars invested in these activities totaled less than $1000.

TYPES OF POKA-YOKES

Poka-yoke is based on prediction and detection. That is, recognizing that a defect is about to occur or recognizing that a defect has occurred. Consequently, there are two basic types of poka-yoke systems. The control poka-yoke does not allow a process to begin or continue after an error has occurred. It takes the response to a specific type of error out of the hands of the operator.

For example, a fixture on a machine may be equipped with a sensing device that will not allow the process to continue unless the part is properly inserted. A 3.5-inch floppy disk will not work if inserted backwards or upside down. As a matter of fact, it won't fit into the drive at all unless properly inserted. A second type of poka-yoke provides some type of warning when an error occurs. This does not prevent the error, but immediately stops the process when an error is detected. This type of poka-yoke is useful for mass production environments with rapid processing as the device prevents mass production of scrapped material.

For environments where large losses of time or resources do not result, a warning poka-yoke is warranted. All that is needed is a way to ensure that the error is investigated and corrected in a timely manner. Poka-yokes can be as simple as a steel pin on a fixture that keeps incorrectly placed parts from fitting properly, or they can be as complex as a fuzzy logic neural network used to automatically detect tool breakage and immediately stop the machine. Surprisingly, the simple low-cost devices tend to be in the majority. Regardless of degree of simplicity, all poka-yokes fall into one of three categories: contact methods, fixed-value methods, and motion-step methods. Each is briefly discussed.

CONTACT METHODS.

Contact methods are based on some type of sensing device which detects abnormalities in the product's shape or dimension and responds accordingly. Interference pins, notches with matching locator pins, limit switches and proximity switches are sometimes used to ensure that a part is positioned correctly before work occurs. Asymmetric parts with matching work fixtures can also alleviate incorrect positioning. If orientation is not critical, symmetrical designs can then be used to prevent defects.

Contact methods are useful in situations which encourage mistakes. Such situations involve rapid repetition, infrequent production, or environmental problems such as poor lighting, high or low heat, excess humidity, dust, noise, or anything which distracts a worker. Paul Dvorak, in "Poka-Yoke Designs Make Assemblies Mistakeproof," an article appearing in Machine Design, recommends that the maintenance engineer investigate at least four areas for potential problems that require contact method solutions:

1. Look for where the product will fail if parts are assembled incorrectly.
2. Look for small features critical to proper assembly.
3. Beware of relying on subtle differences to determine top from bottom or front from back, especially if the parts are painted dark colors.
4. Beware of designs so complicated that they confuse inexperienced operators.

FIXED-VALUE METHODS.

Fixed-value methods are used in processes where the same activity is repeated several times, such as tightening of bolts. This method frequently involves very simple techniques, such as methods that allow operators to easily track how often this activity has been performed. Dvorak gives the example of an operator who is responsible for tightening down six bolts on a product. Before passing the product on, the tightening process is performed a fixed number of times (six).

A simple poka-yoke device would incorporate the use of a wrench dipped in diluted paint. Since untightened bolts will not have paint on them, the operator can easily see if he or she has performed the process the required number of times. A second example (from Dvorak) would be the use of packaged material in the exact (fixed) quantities needed to complete the process. If the bolts were stored in containers of six, the operator could easily see when the process was still incomplete as the box would still contain one or more bolts.

MOTION-STEP METHOD.

The motion-step method is useful for processes requiring several different activities performed in sequence by a single operator. This is similar to the fixed-value situation in that the operator is responsible for multiple activities but instead of performing the same activity multiple times the operator performs different activities.

First, each step in the process is identified by the specific motions needed to complete it. Then devices are created to detect whether each motion is performed and then alert the operator when a step is skipped. An assembly process could utilize a device that senses when all required components are present at the start of the process for each unit. The devices could then detect when each component is removed from its dispenser, If a component is not removed, the sensing device alerts the assembler before he/she can move on to another unit.

Examples of Poka-Yokes

Contact Method ,

Contact Type : A steel pin on a fixture keeps incorrectly placed parts from fitting properly.

Warning Type : A device on a drill counts the number of holes drilled in a work piece; a buzzer sounds if the work piece is removed before the correct number of holes have been drilled.

Fixed-value Type ,

Contact Type : Light sensors determine if each crayon is present in each box; if a crayon is missing, the machines will stop automatically.

Warning Type : Bolts are tightened with a wrench dipped in paint. Bolts with no paint on them are still untightened.

Motion-Step Method ,

Contact Type : A simple proximity switch opens after all components are loaded in the proper order.

Warning Type : A device detects when each component is removed from a dispenser; if a component is not removed, the device alerts the assembler before he can move on to another unit.

SELF CHECKS

Poka-yoke devices which provide the fastest possible feedback about defects and allow workers to assess the quality of their own work are referred to as self-checks. Self-checks can be used to allow workers to rapidly identify slips or work errors such as incomplete or omitted operations and to verify the existence or absence of an attribute. For example, at Brigham and Women's Hospital, a computer system is used to check and process doctors' prescriptions.

EXAMPLES.

A number of "real world" applications are presented in the business and engineering literature. Below are a list of examples of poka-yoke applications. James R. Evans and William M. Lindsay present these examples in their book The Management and Control of Quality:

• Color-coding a wiring template to assist the worker.
• Installing a device on a drill to count the number of holes drilled in a work piece; a buzzer sounds if the work piece is removed before the correct number of holes has been drilled.
• Cassette covers were frequently scratched when the screwdriver slipped out of the screw slot and slid against the plastic covers. The screw design was changed to prevent the screwdriver from slipping.
• A metal roller is used to laminate two surfaces bonded with hot melted glue. The glue tended to stick to the roller and cause defects in the laminate surface. An investigation showed that if the roller were dampened the glue would not stick. A secondary roller was added to dampen the steel roller during the process, preventing the glue from sticking.
• One production step at Motorola involves putting alphabetic characters on a keyboard, then checking to make sure each key is placed correctly. A group of workers designed a clear template with the letters positioned slightly off center. By holding the template over the keyboard, assemblers can quickly spot mistakes.

John Grout presented these examples in "Mistake-Proofing Production," an article written for Production and Inventory Management Journal:

• Trinity Industries Railcar Division workers created a layout jig to avoid having to use a tape measure and chalk to position subassemblies on each car individually. The jig has tops that allow it to be quickly positioned correctly on the car's chassis. Each component that is to be attached to the car has a corresponding cutout on the jig. The jig eliminates two modes of worker error. It eliminates incorrect measurements and inaccurate positioning of parts. It also eliminates the worker vigilance required to ensure all of the components are attached.
• Omitted parts are made very obvious because an empty space exists on the layout jig. Without the jig, there would be no indication that anything is missing. Once parts are spot welded in place the jig is lifted off and welding is completed. Not only is dependence on worker vigilance reduced, cost savings result from the simplified, accelerated process.
• Binney and Smith, maker of Crayola Crayons, uses light sensors to determine if each crayon is present in each box of crayons they produce. If a crayon is missing, the machines will stop automatically. Producing complete boxes of crayons right the first time is the preferred outcome.
• A mail-order computer company has designed its boxes and packing material to avoid mistakes. The inner flaps of the box bottom have a large brightly colored warning to "Stop! Open the other side." When the correct side is opened, a book titled "Setting Up Your Computer" is on top of the packing material. The sequence of the book matches the arrangement of the contents of the box. Each instruction involves the next item from the box.
• Airplane lavatory lights come on only when the door lock is engaged. This keeps customers from failing to lock the door.
• John Deere produced a gearbox that was assembled without oil, mounted on a machine, and required replacement after factor tests. A team streamlined production with a simple proximity switch that opens after all components were loaded into an assembly fixture. The switch prevents workers from using air wrenches to tighten bolts on the assembly until they cycle an oil gun into the gearbox. After filling the gearbox a solenoid releases the interlock sending air to the wrench. Then workers can tighten cover bolts and send the box to the next station.
• The electrical connectors in one machine control formerly used only three-pin connectors to join each in a series. Labels instructed assemblers which boards went where and which connectors should be joined. But in the field, assemblers connecting and disconnecting them wear or bend the pins, which meant putting on a new plug. Soon the label was gone. The simple solution involved three, four and five-pin connectors that cannot join others and demand a single assembly sequence.
• Ficarra's solution to labels that come off is to machine them into parts, especially when the function is to determine the correct orientation.

On Varian machines, assemblers are guided by small machined-in pictures that cannot wear off.

SERVICE APPLICATIONS

Poka-yoke can also be applied to service-based organizations. The following is summarized from the paper "Using Poka-Yoke Concepts to Improve a Military Retail Supply System," which was printed in Production and Inventory Management Journal.

While manufacturing typically only considers errors made by the producer, service industries must consider errors from both the server and the customer. Additionally, service organizations interface in many different ways to transfer a service to the customer. Because of the possibility that service errors can be created by both the customer and the server, service poka-yokes are grouped into two categories: fail-safing the server and fail-safing the customer.

SERVER POKA-YOKES

There are three types poka-yoke systems that can be used to fail-safe the server: task poka-yokes, treatment poka-yokes, and tangible poka-yokes.

TASK POKA-YOKES.

Task poka-yokes focus on server tasks and common mistakes servers make while performing the service/task for the customer. A good example of a control-oriented, task poka-yoke is the coin return machine used in may fast-food restaurants. The coin portion of a customer's change from payment is returned automatically through these machines. This takes the control out of the hands of the cash register operator, eliminating errors and speeding up the processing of customers.

TREATMENT POKA-YOKES.

Treatment poka-yokes focus on the social interaction between the customer and the server (i.e., eye contact, greeting). By mistake-proofing/standardizing what servers say and do to customers, managers can reasonably ensure that customers receive proper, fair and consistent treatment. Burger King utilized warning-oriented, treatment poka-yokes by placing "cue cards" at the service point ensuring that servers know what to say the minute they interface with the customer.

TANGIBLE POKA-YOKES.

Tangible poka-yokes attempt to improve the tangible, physical impression and experience for the customer in addition to the direct task of the server (i.e., dirty office, unkempt server, sloppy documents). Motorola uses a control- oriented poka-yoke in the legal department by having a second lawyer inspect all legal work for spelling, presentation, and arithmetic. In this way, the legal department is ensuring that the "tangibles" of the service are satisfactory in addition to the task of the service (legal work).

CUSTOMER POKA-YOKES

Fail-safeing the customer also consists of three of poka-yoke systems: preparation poka-yokes, encounter poka-yokes, and resolution poka-yokes.

PREPARATION POKA-YOKES.

Preparation poka-yokes attempt to fully prepare the customer before they even enter the service. An example of a warning-oriented, preparation poka-yoke is the notice a university sends to each student prior to registration for the next semester detailing the courses he needs to finish his degree. This system could be converted to a control system by having an automated registration process which would not allow students to sign up for classes out of sequence or until all prerequisites are met.

ENCOUNTER POKA-YOKES.

Encounter poka-yokes attempt to fail-safe a customer at a service who may misunderstand, ignore, or forget the nature of the service or their role in it. A good example of a control-oriented, encounter poka-yoke is the use of concrete curbing at an oil& lube shop that directs customers so that they do not/cannot pull the wrong way into the station. This system also assists in the selection process so that customers are not served out of order.

RESOLUTION POKA-YOKES.

Resolution poka-yokes attempt to remind customers of the value of their input to the continuous improvement of a service. A hotel which uses an automated check-out system through the television in each room could attach a few questions to the check-out process to ensure the customer provides feedback on key issues. This would be a control-oriented resolution poka-yoke. Obviously, one of the keys to the success of any customer-oriented poka-yoke is to obtain willing customer participation.

BARRIERS TO IMPLEMENTATIONAND RECOMMENDATIONS

Patel, Dale and Shaw note that there are a number of barriers a firm may face when implementing poka-yoke devices within their system. These include:

• Difficulty in accepting change
• Justification of the investment
• Using inappropriate and ineffective methods
• Time requirements
• Difficulty encountered as a result of continuous process

Stewart and Grout, in an article entitled "The Human Side of Mistake-Proofing," make the following recommendations for the implementation of poka-yoke devices:

1. The outcome of the process or routine must be known in advance so as to have a standard for comparison.
2. The process must be stable, i.e., outcomes are not changing.
3. There must be an ability to create a break between cause and effect in the process so as to provide an opportunity to insert a poka-yoke.
4. Environments requiring substantial operator skill are prime locations for poka-yoke devices.
5. Environments where training or turnover cost is high are prime locations for poka-yoke devices.
6. Environments with frequent interruptions and distractions are prime locations for poka-yoke devices.
7. Environments with a consistent set of mixed products are prime locations fopoka-yoke devices.
8. The beginning of any process where there are multiple other possible processes that could be initiated are a prime location for poka-yoke devices.
9. Locations in the process with similarly positioned or configured parts, controls or tools are prime locations for poka-yoke devices.
10. Any point in the process requiring replacement or orientation of parts in order to prevent mispositioning is a prime location for poka-yoke devices.
11. Any point in the process where adjustments are made for machine or process setups is a prime location for poka-yoke devices.

John Grout attributed defects to three sources: variance, mistakes, and complexity. Complexity requires techniques which simplify the process while managing variance can be accomplished by utilizing statistical process control (SPC). However, if quality problems are the result of mistakes, poka-yoke devices are the appropriate technique to use. In this case, poka-yoke provide an even more effective quality improvement tool than SPC. Other poka-yoke benefits include reduced training costs and the advantage of freeing workers' time and minds for more creative and value-adding activities.

Circumstances where poka-yoke is not the appropriate response are situations involving high speed production, situations where X-bar (Χ̅) & R charts are effective, and use in destructive testing. Other situations, however, provide opportunities for simple, inexpensive, and fail-safe devices to improve performance. Grout relates the example of Lucent Technologies, which reported that half of their 3,300 mistake-proof devices cost less than $100. However, they estimate a net savings of $8.4 million or about $2,545 per device. Poka-yoke is a most impressive and powerful tool.

FURTHER READING:

Dvorak, Paul. "Poka-Yoke Designs Make Assemblies Mistake-proof." Machine Design, 10 March 1998, 181–184.
Evans, James R., and William M. Lindsay. The Management and Control of Quality. South-Western Publishing, 2004.
Ghinato, Paulo. "Quality Control Methods: Towards Modern Approaches Through Well Established Principles." Total Quality Management 9, no. 6 (August 1998).
Grout, John R. "Mistake-Proofing Production." Production and Inventory Management Journal 38, no. 3 (3rd Quarter 1997): 33–37.
Larson, Melissa, "Drill Template Illustrates 'Poka-Yoke.'" Quality 10, no. 6 (June 1998).
Patel, S., B.G. Dale and P. Shaw. "Set-up Time Reduction and Mistake Proofing Methods: An Examination in Precision Component Manufacturing." The TQM Magazine 13, no. 3 (2001): 175–179.
Snell, Todd, and J. Brian Atwater. "Using Poka-Yoke Concepts to Improve a Military Retail Supply System." Production and Inventory Management Journal 37, no. 4 (1996).
Stewart, Douglas M., and John R. Grout. "The Human Side of Mistake-Proofing." Production and Operations Management 10, no. 4 (2001): 440–459.
Stewart, Douglas M. and Steven A. Melnyk. "Effective Process Improvement: Developing Poka-Yoke Processes." Production and Inventory Management Journal 41, no. 4 (2000): 48–55.

Prepared by :

Putra-Design

Bandar Puncak Alam, Malaysia.

LCD or Plasma HDTVs: Which to Choose?

The war between plasma and LCD flat-panel TVs rages on, and no doubt you've heard the propaganda from both camps. While LCD has traditionally been more expensive than plasma at the larger sizes, that gap is diminishing -making other factors such as performance and features more significant. We'll take you through the pros and cons of each technology to help you make the important decision: whether to buy a plasma or LCD television?

Plasma Flat Panels

Benefits:

• Better contrast and deeper blacks. Plasma displays are known for their deep, inky-black levels, which result in better contrast and a more three-dimensional picture. Panasonic and Pioneer are especially well known for their sets' high-quality black levels, setting the standard for all other plasma sets. By comparison, LCDs have a more difficult time "turning off" their backlighting mechanisms for a truly dark image. On the other hand, they are generally brighter than plasma displays, and therefore perform better in situations where there is a lot of ambient light (more on that later).

• Don't suffer from motion blur on action. Due to technical reasons we won't get into here, LCDs are often victims of motion blur- aka image smearing - which results in fast-action or sports footage looking blurry or smeared across the screen. In a very bad case, if a golf ball is flying through the sky, you might see a comet-like trail behind it.

• Unlimited viewing angle. Unlike LCDs, off-axis viewing of a plasma set will look the same as if you were looking at the plasma sitting directly in front of it. In short, image quality is consistent from any seat in the house.

• Cost slightly less than LCD sets. While the difference in price is shrinking, plasmas are slightly less expensive than LCDs, especially at larger sizes. However, this doesn't necessarily apply to top-end models.

Drawbacks:

• Short-term image retention a possibility. Plasmas have always gotten a bad rap for burn-in or image retention: When an image, such as a station logo or stock ticker, remains on the screen for too long, you may see a faint ghost of the image after it disappears. For most good plasma displays though, this is a non-issue, and any ghosting that appears should quickly go away. A lot of manufacturers use screen savers if an image is paused for too long to prevent image retention.

• Screens can suffer from glare in bright rooms. Plasma TVs' glass panels are known to reflect light and make them harder to watch in a bright room. Many manufacturers are using special techniques to minimize reflections, however, and some of them, such as Panasonic's anti-reflective filter, minimize these reflections and improve performance in brighter rooms. Look for antiglare options when you are shopping for a plasma TV.

• Use slightly more power than LCD displays per square inch.

• Fewer choices. LCD panels are everywhere and come in a wider variety of sizes. There is a little less variety to choose from when it comes to picking a plasma display.

The bottom line:

While we could take the stance that both technologies are equally good, and the choice is up to your personal preference, we won't go for the easy cop-out. The fact is, plasmas have a slight edge when it comes to a truly cinematic picture. If you are a cinephile who likes to watch a lot of different film sources such as Blu-ray discs or DVDs, plasma is your best bet - especially if you have some control over ambient light.

The technology's deeper blacks, sharper contrast and absence of motion blur make it ideal for almost any application. Just watch out for image glare on untreated plasma displays, and make sure your plasma can stand up to the amount of uncontrollable light in your room.

LCD HDTVs

Benefits:

• Brighter images. LCD panels offer brighter pictures than plasma, making them great models for viewing in a well-lit room.

• No screen reflection. LCD televisions' matte screens don't fall prey to screen glare like plasma displays do. However, there are some exceptions to this rule, so be on the lookout for that errant non-matte screen when shopping for an LCD.

• No risk of image retention. Unlike plasma, there is absolutely no fear of image retention on an LCD display.

• Slightly lower power consumption. In a world that is becoming more energy-conscious with every passing day, consuming less power is a strong selling point. However, almost every manufacturer-plasma and LCD- is incorporating special energy-saving modes into their sets. Check power-consumption ratings and features before you buy.

Drawbacks:

• Limited viewing angle. LCD TVs' viewing angles are not as wide as plasmas. This means that if you are sitting off to the sides of the TV (or below it), the image may appear somewhat off in terms of color, contrast, and brightness.

• Blacks are not as deep as plasmas. LCDs don't begin to compare with plasmas in the black-level department. However, there are some new LCDs that use light emitting diode technology (LED) to more effectively "turn off" the black parts of the image during dark moments. These models are relatively expensive, however.

• Can suffer from motion blur. While motion blur or image smearing can be a factor when watching fast-moving action on an LCD, most manufacturers have introduced frame-interpolation technology into their LCD sets that add frames to double or even quadruple LCD's 60Hz frame rate. If motion blur is a concern, demo the LCD using sports source material. Most consumers won't notice motion blur on a screen with frame-interpolation technology.

The bottom line

While LCDs have a slight disadvantage when it comes to watching cinematic content, they do have their benefits. They can stand up to almost any viewing environment, such as watching a football game during broad daylight in a room flooded with natural light. If this sounds like your viewing space, LCD may be the way to go.

Additionally, if you are looking for an HDTV at a smaller screen size, then LCD is the only way to go, as plasmas are not manufactured below 42 inches. You have a lot more choice when it comes to picking an LCD panel, and most of them are quite good, especially those from Samsung, Sony and Sharp.

Putra-Design

Lukisan teknik

Lukisan Lakaran (Mesin Terbang Leonardo da Vinci)

Lukisan Pemasangan 2 Matra

Lukisan Terperinci atau Lukisan Pembuatan



Lukisan Pemasangan Terurai 3 Matra dilukis dengan sistem CADD

Lukisan Teknik; juga dikenali sebagai lukisan kejuruteraan, adalah cara untuk menghasilkan lukisan pelan yang mengambarkan dengan tepat sesuatu objek teknikal, seni bina dan kejuruteraan. Dengan kata lain lukisan kejuruteraan merupakan alat komunikasi atau bahasa perhubungan di kalangan mereka yang terlibat dengan dunia kejuruteraan.

Ia adalah satu dokumen, dalam bentuk bergambar dan sedikit nota. Ia mengandungi semua maklumat penting bagi tujuan pembuatan atau pengilangan; iaitu mungkin mengandungi satu komponen tunggal, sebahagian kumpulan binaan atau satu barangan lengkap yang menunjukkan keseluruhan komponen.

Secara teknikalnya lukisan kejuruteraan boleh dipecahkan kepada dua iaitu:-

Lukisan Mesin ; Iaitu lukisan pemasangan yang dikhususkan kepada proses mencantum dan membuka komponen untuk memenuhi tujuan pembuatan, selenggaraan atau persembahan..

Lukisan Kerja ; Iaitu lukisan yang menerangkan dengan terperinci bagaimana sesuatu komponen itu harus dihasilkan dan apakah yang patut dicapai oleh sesuatu pengeluaran itu. Lukisan ini juga menunjukkan sifat akhir sesuatu komponen. Lukisan ini termasuklah Lukisan Terperinci, Lukisan Butir, Lukisan Bahagian-bahagian dan Lukisan Pembuatan.

Orang-orang yang mempraktikkan seni ini dikenali sebagai pelukis plan. Sebelum komputer berkembang pesat kebanyakan lukisan kejuruteraan dilukis secara insani (Manual). Dewasa ini tugas melukis dipermudahkan dengan kewujudan sistem Rekabentuk Terbantu Komputer. Namun sama ada sesuatu lukisan itu dilukis secara insani atau dengan bantuan komputer, lukisan berkenaan hendaklah mempunyai ciri kebolehasilan semula yang baik, serta mematuhi spesifikasi lukisan dan piawaian lukisan kejuruteraan tertentu yang telah ditetapkan.

Putra-Design

INTRODUCTION

Manufacturing plays a very important role in a country's progress towards industrialisation. Competitivenes in manufacturing contributes more than other industries towards competitivenes of nations. However, achieving competitiveness in manufacturing is a challenge by itself. To take up this challenge, skilled, competent and creative workforce is a pre-requisite.
The Manufacturing System Engineering is designed for those who wish to enhance their knowledge in manufacturing technology and processes.

In a recent study by the United States Academy of Engineering, the greatest engineering achievements in this century that have shaped and changed the world were electrification, automobile, airplane, water supply and distribution, electronics, radio and television, agricultural mechanization, computers, telephone, air conditioning and refrigeration, highways, spacecraft, internet, imaging, household appliances, health technologies, petroleum and petrochemical technologies, laser and fiber optics, nuclear technologies and high-performance materials. These engineering innovations and inventions indicate the important role that mechanical engineers played in developing, operating and manufacturing new machines, devices and processes that have benefited mankind in this century.

In a commercial world mechanical engineers must have not only technical skills, but also management skills necessary to get the job done while ensuring their company continues to function efficiently. To do this they must have a deep understanding of scientific principles and engineering processes. At the undergraduate level, mechanical engineers learn the science and engineering principles of designing and building machines, structures, components, power-trains, pumps, compressors, turbines, engines, power plants, furnaces, refrigerators, air conditioners, manufacturing systems and processes and more.

As graduate students, this learning process is enhanced through advanced formal courses and laboratory research experience. They conduct in-depth research and benefit from the up-to-date knowledge and facilities. Graduate students also benefit from research grants from industry and government as they work with the faculty members of the department in the study of thermal sciences; mechanics; mechatronics and robotics; design and manufacturing; and materials processing. They must make decisions based on fundamental knowledge, analytical skills, creativity, perspective, and ethics. They must also apply advanced technology and science by combining basic knowledge with the application of engineering and scientific principles.

Putra-Design-UKM