Six Sigma and Beyond: Design for Six Sigma, Volume VI

Developing a product that can be manufactured economically and consistently to be delivered to the marketplace in quantity and that will work satisfactorily for the customer takes a well established and precisely controlled design and development cycle. Events must be scheduled to occur at precise times to phase the product into the marketplace . To develop a new internal combustion engine for an automobile takes about a three-year design cycle (down recently from five years ), while a new minicomputer takes about 18 months. Although the timing may be different for different companies, the activities comprising a design and development cycle are similar. The following is representative of the activities in a product development cycle:

RELIABILITY IN DESIGN

The cost of unreliability is:

It has been demonstrated in the marketplace that highly reliable products (failure free) gain market share. A very classic example of this is the American automotive market. In the early 1960s, American manufacturers were practically the only game in town with GM capturing some 60% of the market. Since then, progressively and on a yearly basis the market has shifted to the point where Flint (2001) reports that now GM has a shade over 25% without trucks and Saab, Ford 14.7% without Volvo and Jaguar, and Chrysler about 5%. The projections for the 2002 model year are not any better with GM capturing only 25%, Ford 15%, and Chrysler 6%. The sad part of the automotive scene is that GM, Ford, and DaimlerChrysler have lost market share, and sales are continually nudging down with no end in sight. That is, as Flint (2001, p. 21) points out, "they are not going to recover that market share, not in the short term , not in the next five to ten years."

The evidence suggests that the mission of a reliability program is to estimate, track, and report the reliability of hardware before it is produced. The reliability of the equipment must be reported at every phase of design and development in a consistent and easy-to-understand format. Warranty cost is an expensive situation resulting from poor manufacturing quality and inadequate reliability. For example, the chairman and chief executive of Ford Motor Company, Jacques Nasser, in the 1st quarter of 2001 leadership cascading meeting made the statement that in 1999, there were 2.1 times as many vehicles recalled as were sold. In 2000, there were six times as many. By way of comparison:

For each car sold, the manufacturer must collect and retain this expense in a warranty account.

COST OF ENGINEERING CHANGES AND PRODUCT LIFE CYCLE

The stage of product development/manufacturing and the cost of an engineering change have been estimated many times by many different industries and various trade magazines as a cost that grows by a factor of five to ten as one moves from early design to manufacturing. Typical figures for this high cost are

Therefore, reliability can play an important role in designing products that will satisfy the customer and will prove durable in the real world usage application. The focus of reliability is to design, identify, and detect early potential concerns at a point where it is really cost effective to do so.

Reliability must be valued by the organization and should be a primary consideration in all decision making. Reliability techniques and disciplines are integrated into system and component planning, design, development, manufacturing, supply, delivery, and service processes. The reliability process is tailored to fit individual business unit requirements and is based on common concepts that are focused on producing reliable products and systems, not just components.

Any organization committed to satisfy the customer's expectations for reliability (and value) throughout the useful life of its product must be concerned with reliability. For without it, the organization is doomed to fail. The total reliability process includes robustness concepts and methods that are integrated into the organization's timing schedule and overall business system. Cross-functional teams and empowered individuals are key to the successful implementation of any reliability program.

Reliability concepts and methods are generally thought of as a proprietary domain of only the product development department or community. That is not completely true. Reliability may be used anywhere there is a need for design and development work, such as manufacturing and tooling. However, it does not address actions specifically targeted at manufacturing and assembly. This is the reason why under Design for Six Sigma (DFSS), reliability becomes very important from the "get go." To be sure, reliability currently does not include all the elements of the Advanced Product Quality Plan (APQP), but it is compatible with APQP. It outlines the three quality and reliability phases that all program teams and supporting organizations should go through in the product development process to achieve a more reliable and robust product. The three phases stress useful life reliability, focusing specifically on the deployment of customer-driven requirements, designing in robustness, and verifying that the designs meet the requirements.

RELIABILITY IN THE TECHNOLOGY DEPLOYMENT PROCESS

Technology is ever changing on all fronts. Customers expect increased reliability and better quality for a reasonable cost. Reliability may indeed play a major role in bringing technology, customer satisfaction, and lower cost into reality. Let us then try to understand the process of support and the cascading of requirements throughout the Technology Deployment Process (TDP).

Understanding the TDP begins with the recognition that this process has three phases and each phase has specific requirements. The three phases are pre deployment process, core engineering process, and quality support. In the pre deployment process, there are three stages with very specific inputs and outputs. In core engineering, the development of generic requirements begins, and in quality support, the "best" reliability practices are developed.

1. Pre-Deployment Process

Three stages are involved here. They are:

  1. Identify/select new technologies: The main function of this stage is to identify and select technology for reliable and robust products that meet future customer needs or wants. In essence, here we are to develop and understand:

    • Customer wants process

    • Competitive analysis

    • Technology strategy/roadmap

  2. Develop/optimize technology to achieve concept readiness: The main function of this stage is to sufficiently develop and prove through analytical and/or surrogate testing that the technology meets the functional and reliability requirements for customer wants or needs under real world usage conditions. In essence, here we are to generate, understand, and develop readiness through:

    • Reviewing quality history of similar systems/concepts

    • Understanding real world usage profile

    • Defining functional requirements of system

    • Planning for robustness

    • Reviewing quality/reliability/durability reports or worksheets

  3. Develop/optimize technology to achieve implementation readiness: The main function of this stage is to optimize the technology to meet functional and/or reliability requirements. Additionally, the aim is to demonstrate that the technology is robust and reliable under real world usage conditions. In essence, here we are to further understand the requirements by:

    • Refining design requirements

    • Designing for robustness

    • Verifying the design

    • Reviewing quality/reliability/durability reports or worksheets

2. Core Engineering Process

Develop generic requirements for forward models by providing product lines with generic information on system robust design, such as case studies, system P-diagrams, measurement of ideal functions, etc. In this stage, we also conduct competitive technical information analysis to our potential product lines through test-the-best and reliability benchmarking. Some of the specific tools we may use are:

The idea here is to be able to develop common-cause problem resolution, that is, to be able to identify common-cause problems/root causes across the product line(s) and champion corrective action by following reliability disciplines. In essence then, core engineering should:

3. Quality Support

Identify best reliability practices and lead the process standardization and simplification. Develop a toolbox and provide reliability consultation.

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