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by Ellen Domb, Ph.D.

Six Sigma projects of all kinds frequently reach a point where the analysis is done but the next step remains unclear. In order to figure out what to do next, the project team must employ those brainstorming and related process-improvement tools recommended by Six Sigma and other methods, such as total quality management and quality circles. However, many of these tools depend on intuition and team members’ knowledge, neither of which is reliable in a strictly scientific sense.1

Between 1946 and 1985, the Russian scientist G.S. Altshuller and his colleagues developed a theory of inventive problem solving known by the Russian acronym “TRIZ.” Based on logic and data rather than intuition, TRIZ accelerates a project team’s ability to solve problems. TRIZ relies on the study of problem-and-solution patterns, not an individual’s or group’s spontaneous creativity.

To develop the theory, Altshuller and his colleagues analyzed more than 400,000 patents to discover the patterns that predict breakthrough solutions to problems. TRIZ research began with the hypothesis that universal principles of invention underlie the creative innovations that advance technology. Once these principles are identified and codified, they can be taught and will help make the process of invention more predictable.

Two basic truths in the TRIZ doctrine maintain that:

Somebody, someplace, has already solved any problem--or one very similar to it.

Creativity means finding that solution and adapting it to a current problem.

 

The research has proceeded in several stages. Four primary findings indicate that:

Problems and solutions are repeated across industries and sciences.

Classifying the contradictions in a given problem makes it possible to predict creative solutions to that problem.

Patterns of technical evolution are repeated across industries and sciences.

Creative innovations use scientific effects outside the field in which they were developed.2

Identifying problem-solution patterns

The practice of TRIZ consists of identifying problem-solving patterns, identifying patterns of technical evolution, identifying methods of using scientific effects, and applying them to a specific situation confronting the developer, as illustrated on page 56.

A powerful demonstration of this method can be found in the pharmaceutical industry. Tailored bacteria are used to cultivate human hormones, producing a superior product to those refined from animal sources. To produce the hormone, though, large quantities of tailored bacteria cells must be cultured, the cells broken open and the cell walls removed. A mechanical method for breaking the cells produced an 80-percent yield, but it was variable at best.3 More recently, the yield had fallen to 65 percent; the pharmaceutical industry wished to increase production to much higher yields.

The problem from a TRIZ standpoint is to find a way to produce the product with no waste, at 100 percent yield and without new complications. TRIZ theory states, “The problem should solve itself.” A generic TRIZ solution, based on patterns of technical evolution, replaces mechanical devices with fields. This may seem very general, but it led pharmaceutical researchers to analyze all the resources available in the problem (e.g., the cells, cell walls, surrounding fluid and its motion, the processing facility, etc.). They concluded that three specific solutions had high potentials for solving the problem:

Cell walls could be broken by sound waves.

Cell walls could be sheared open as they pass through the processing facility.

An enzyme in the fluid could “eat” cell walls and release the contents at the desired time.

All three methods had been tested successfully, and the least expensive, highest-yield method was soon in production.

The general TRIZ solutions referred to on page 60 have been developed during 65 years of research and organized in many different ways. These include analytic methods such as:

Ideal final result

Functional analysis and trimming

Locating zones of conflict (known to Six Sigma problem solvers as root cause analysis)

Other solutions are more prescriptive and include:

The 40 principles of problem solving

Separation principles

Laws of technical evolution and technology forecasting

Forty principles of problem solving

When solving any technical problem, one tool or many can be used. The flowchart below illustrates this.

The 40 principles of problem solving are TRIZ’s most accessible “tool.”5 These principles repeat across many fields as solutions to many general contradictions. They also lie at the heart of many Six Sigma problems. According to TRIZ methodology, contradictions should be eliminated. The methodology recognizes two categories of contradictions:

Technical contradictions. These are the classical engineering tradeoffs in which the desired state can’t be reached because something else in the system prevents it. In other words, when something gets better, something else gets worse. Examples of technical contradictions include the following:

  • Product gets stronger (i.e., good), but the weight increases (i.e., bad).
  • Bandwidth increases (good) but requires more power (bad).
  • Service is customized to each customer (good), but the service delivery system becomes complicated (bad).
  • Automobile airbags deploy quickly to protect the passenger (good), but the faster they deploy, the more likely they will injure or kill small or out-of-position people (bad).

Physical contradictions. Also called “inherent” contradictions, these include situations in which one object or system has contradictory, opposite requirements. Everyday examples abound:

  • Surveillance aircraft should fly fast to their destinations, but also slowly to collect data over the target.
  • Software should be easy to use but include many complex features and options.
  • Coffee should be hot for enjoyable drinking but cool enough to prevent burning consumers.
  • Training should be thorough but not take any time.
  • Airbags must inflate both quickly and slowly.

TRIZ includes 40 principles for solving technical/tradeoff contradictions and four separation principles for solving physical/inherent contradictions. Many problems can be stated as both physical and technical contradictions. In general, the most comprehensive solutions come from the physical contradiction formulation, whereas the most prescriptive solutions derive from the technical contradictions. People usually learn to solve technical contradictions first because the method is very concrete. Afterward, they learn to solve physical contradictions, then use both methods interchangeably, depending on the problem.

The contradiction matrix

TRIZ research has classified 39 features for technical contradictions. Once a contradiction is expressed in the technical form (i.e., the tradeoff), the next step is to locate specific features in the contradiction matrix.6 The figure on below shows a piece of the matrix.

To use the matrix, find the row that most closely matches the feature or parameter you’re improving in your tradeoff and then the column that most closely matches the feature or parameter that degrades it. The cell at the intersection of that row and column will have several numbers. These identify specific principles of invention that are most likely to solve the problem, that is, to lead to a breakthrough solution instead of a tradeoff.

For example, consider the proposal to change airbag inflation speed to reduce injuries to small occupants. The tradeoff is that injuries in high-speed accidents increase. Translating this into TRIZ matrix terms, the parameter that improves is “duration of action of a moving object” (row 15) and the parameter that worsens is “object-generated harmful factors” (column 31). The circle in the figure highlights the cell at the intersection and includes the numbers 21, 39, 16 and 22. These are identifiers for four principles of invention.

Usually the principles are accompanied by examples from a variety of industries. The design or problem-solving team uses the text, those examples and examples from its own previous applications to develop a solution.

Consider the application of principle 21 to the airbag example:

Principle 21: Skipping. Conduct a process or certain stages of it (e.g., destructible, harmful or hazardous operations) at high speed. For example:

  • Use a high-speed dentist’s drill to avoid heating tissue.
  • Cut plastic faster than heat can propagate in the material to avoid deforming the shape.

One solution to the airbag problem, then, would be to inflate the bag faster than current practice, so that it’s fully inflated when it impacts a small person. The “depowered” air bag has been proposed as a solution of this type. By using less power, the bag’s acceleration is less and injuries will be reduced. Conversely, smaller bags with higher power would reach full inflation sooner so that passengers would be protected from accidents and not injured by the bag.

TRIZ outlines four ways to resolve physical or inherent contradictions:

Separation in time

Separation in space

Coexistence of contradictory properties in different subsystems

Move the problem to the super- or subsystem

A very common Six Sigma transactional problem can be expressed as an inherent contradiction: We want everyone to understand all the Six Sigma methods so we can improve all our processes, but we don’t want everyone to stop working for the time required for training. In other words, we want both a lot of training and no training.

Examining the separation principles, we see possible solutions in all of them. For example, separation in time suggests training Black Belts first, then having Black Belts train other employees while working on projects.

Recent case studies

TRIZ was developed from the study of patents, but the underlying creative principles discovered apply to a wide variety of transactional and product problems. Recent case studies of actual situations include the following:

Transportation. Singapore needed to find a way to manage automobile traffic on the Sentosa, the city’s entertainment island. Applications of TRIZ methods developed eight families of solutions.7

IT product development. DelCor Interactives International doubled the value to the customer of its patient interview system for optical offices. The company applied TRIZ feedback and self-service principles8 to overall product development. It also applied the principles of segmentation (i.e., “taking out” and “composite construction”) to training and support.

Education. School administrators are enhancing their creativity in dealing with situations ranging from allocating budget for special education to building five schools using funds for four, to improving racial harmony.9

Waste processing. Dairy farm operators could no longer dry cow manure due to increased energy costs. TRIZ identified the method used for concentrating fruit juice, which requires no heat.10

Warranty cost reduction. Ford Motor Co. used TRIZ to solve a persistent problem with squeaky windshields that cost several million dollars each year.11 Previously, the manufacturer used TRIZ to reduce idle vibration in a small car to less than one-third the initial value.12

Additionally, TRIZ works well with Six Sigma. As with other tools in that methodology, TRIZ is procedural; it can be used by individuals or teams, and helpful case studies abound. The best way to explore TRIZ is to start with a problem you haven’t solved satisfactorily and apply these effective methods to it.

About the author

Ellen Domb, Ph.D., is the editor of The TRIZ Journal, an online publication available at www.triz-journal.com, and the principal TRIZ consultant for the PQR Group in Upland, California. TRIZ is Domb’s sixth career: She has been a physics professor, an aerospace engineer, an engineering manager, a product-line general manager and a strategic planning/quality improvement consultant.

References

1. Smith, Larry. 2001. www.asq.org/pub/sixsigma/past/vol1_issue1/evolution.html

Tennant, Geoff. 2003. “TRIZ for Six Sigma.” www.sixsigmatriz.com

2. Altshuller, Genrich. 1988. Translated by Anthony Williams. Creativity as an Exact Science. Gordon and Breach, New York.

3. Anderson, Wesley, Justin Farrell, and Karen Tate. 1997. “TRIZ Applied to Solving Manufacturing Problems and Improvement.” Proceedings of the third Annual International Total Product Development Symposium, American Supplier Institute, Livonia, MI.

4. Rantanen, Kalevi, and Ellen Domb. 2002. Simplified TRIZ. CRC Press, Boca Raton, Florida.

5. Domb, Ellen. 1997–2003. “Tutorial on

Contradictions.” The TRIZ Journal, www.triz-journal.com, July 1997.

Altshuller, Genrich. 1988. Translated by Anthony Williams. Creativity as an Exact Science. Gordon and Breach, New York.

6. Domb, Ellen. 1997–2003. “Tutorial on

Contradictions” The TRIZ Journal, July, 1997.

Mann, Darrel, and Ellen Domb. “40 Principles for Business, with Examples.” The TRIZ Journal, September 1999.

7. Zhang, Jun, Tan Kay-Chuan, and Chai Kah-Hin. “Systematic Innovation In Service Design Through TRIZ.” The TRIZ Journal, September 2003.

8. Domb, Ellen, and David Corbin. 1998. “QFD, TRIZ and Entrepreneurial Initiative.” Proceedings of the 10th Quality Function Deployment Symposium, Novi, MI. Reprinted in The TRIZ Journal, September 1998.

9. Hooper, Don, Kathy Aaron, Holly Dale, and Ellen Domb. 1998. “TRIZ in School District Administration.” The TRIZ Journal, February 1998.

10. Raskin, Andy. 2003. “A Higher Plane of Problem Solving.” Business 2.0 Magazine, June 2003.

11. Lynch, Michael. 1997. “Windshield/Backlight Molding Squeak and Flutter (Buzz) Problem.” Proceedings of the third Annual International Total Product Development Symposium, American Supplier Institute, Livonia, MI. Reprinted in The TRIZ Journal, January 1998.

12. Smith, Larry. 1996. “Using TRIZ to Reduce Vibration During Idling.” Proceedings of the 12th Annual GOAL/QPC Symposium, GOAL/QPC. Methuen, MA.