Design for Six Sigma

DFSS-Design for six sigma is covered in the following topic areas:

  • DFSS roadmaps
  • Quality function deployment 
  • Failure mode and effects analysis varieties

DFSS- Design for Six Sigma Roadmaps

Design for six sigma is the suggested method to bring order to product design. analysis has shown that 70-80% of all quality problems are design related. Emphasis on manufacturing side alone will concentrate at the tail end of the problem solving process. The emphasis should be at the front end. Problem solving at the downstream end is more costly and time consuming than fixing it at the source.

Why Design for Six Sigma

NIST in 1999 reported that the automotive supply chain lost at least a billion dollars a year due to poor interoperability of digital designed product data.

There has been considerable emphasis in recent years by American industry in downsizing, restructuring, process redesign, and instituting cost containment, etc. These methods are directed at holding the line on cost. Gary Hamel describes this as denominator management.

In the business world, the equation for return on investment, or return on net operating assets, has  both a numerator - net income, and a denominator - investment. Managers have found cutting the denominator, investment in people, resources, materials, or other assets is an easy way to make the desired return on investment rise (at least short term).

To grow the numerator of the equation, requires a different way of thinking. That thinking must include ways to increase sales or revenues. One of the ways to increase revenues must include introducing more new products for sale to customers.

Cooper R. states that new products account for a large percentage of company sales (40%) and profits (46%). of course, not every new product will survive. Two Studies listed below provide some statistics:

Table 1.1 Progression of New Products Through Development

Table 1.1 indicates a large amount of ideas are needed. These ideas are sorted, screened and evaluated in order to obtain feasible ideas, which enter the development stage, pass into launch stage and become successful products.

To grow the numerator Cooper R. provides more details of how winning products are obtained:

  • 1. A unique, superior product: This is a product with benefits and value for the customer.
  • 2. A strong market orientation: An understanding of customer needs and wants exists.
  • 3. Predevelopment work: upfront activities such as screening, market analysis, technical assessment, market research, and business analysis are vital before development starts.
  • 4. Good product definition: A company must undertake good product and project definition before development starts.
  • 5. Quality of execution: The development process has many steps. A company must execute these steps with the proper amount of detail and correctness.
  • 6. Team effort: Product development is a team effort that includes research and development, marketing, sales, and operations.
  • 7. Proper project selection: Poor projects must be killed at the proper time. This provides adequate resources for the good projects.
  • 8. Prepare for the launch: A good product launch is important and resources must be available for future launches.
  • 9. Top management leadership: Management has a role to play in the product development process. They must provide guidance, strategy, resources, and leadership.
  • 10. Speed to market: Product development speed is the weapon of choice, but sound management practices should be maintained.
  • 11. A new product process: This is a screening (stage gate) process for new products.
  • 12. An attractive market: An attractive market makes it easier to have a successful product.
  • 13. Strength of company abilities: The new product provides a synergy between the company and internal abilities.

There are many product development processes to choose from. Rosenau suggests that the former "relay race" process (one function passing the product from marketing to engineering to manufacturing and back through the loop) is obsolete. Multi-functional team activities involving all departments are necessary for effectiveness and speed to market. The Process is comprised of 2 parts: a "fuzzy front end"(idea generation and sorting) and new product development(NPD). 

The complete NPD process includes 5 activities:

  • Concept study: A study is needed to uncover the unknowns about the market, technology, and/or the manufacturing process.
  • Feasibility investigations: There is a need to determine the limitations of the concept. Find out if the unknowns are resolvable, or if new research improves the project.
  • Development of the new product: This is the start of the NPD process. This includes the specifications, needs of the customer, target markets, establishment of multi-functional teams, and determination of key stage gates.
  • Maintenance: These are the post delivery activities associated with the product development.
  • Continuous learning: Project status reports and evaluations are needed to permit learning.
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