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Using Analogies to Develop Breakthrough Concepts

| On 11, Apr 1998

Ellen Domb, Ph.D.
The TRIZ Institute, 190 N. Mountain Ave., Upland, CA 91786 USA
+1(909)949-0857 FAX +1(909)949-2968
©1998, Ellen Domb

Both the classical and software-based TRIZ methods rely heavily on the use of analogy as a teaching method and as a problem solving method. Typically, the TRIZ practioner decides what problem to solve, and frequently redefines the problem by any of the following methods:

  • Using ARIZ—see the article in this issue by Marconi
  • Using individual tools of ARIZ –see tutorials by this author on the Ideal Final Result and on Finding the Zones of Conflict in The TRIZ Journal archive, and the articles by Gregory Frenklach in this issue and earlier issues, and James Kowalick’s articles on triad analysis and S-Field analysis.
  • Using other tools of problem analysis—Quality improvement tools, theory of constraints analysis, etc.

The pratitioner then selects specific tools that will solve the re-defined problem. The 40 Principles of Problem Solving are the oldest tools of TRIZ, and exemplify the use of analogies. (See the tutorial article on Contradictions by this author in July, 1997, and the book report in this issue on the new translation of Altshuller’s book on the 40 Principles by Lev Shulyak.) The principle is selected, either by means of the contradiction matrix, or by other means. The method is the same, regardless of the resource (books, software, class notes, etc.) :

    1. Read the principle. Some solutions will become obvious immediately.
    2. Read the examples. Examples for each principle in the Altshuller book and in the software packages come from a wide variety of sciences, such as mechanical engineering, agriculture, materials processing, etc.
    3. Use the examples to gain understanding of the principle and create a solution to your problem.

While teaching TRIZ, I have observed that this method works for about 70% of the students, who are mostly technical professionals in engineering and manufacturing, as well as a significant minority of people who are applying TRIZ to solve non-technical problems. But, about 30% of the people I have observed have difficulty between steps 2 and 3; that is, they do not make the connection between the examples of the principle and their own problem, so they don’t get any benefit from the principle or the examples.

To help them, I developed the method that is shown in the rest of this article. Surprisingly, people in the “70% group” who had not appeared to need help with understanding the analogies, frequently use the worksheets and report that they get additional insights from taking the time to analyze the analogies in this manner.

The outline of the method is as follows:

    1. Perform functional analysis or Su-Field analysis to identify the object acted on, the object doing the action (the tool, in Su-Field language) and the force or energy or field by which the force is transmitted. Do this for your problem, and for the example.
    2. Identify the system elements in your problem and in the example. You will need to do this twice for the example, once for the initial situation, and once for the improved situation. The elements of the system are
    • Object
    • Tool
    • Energy transmission
    • Transmission means for the energy (Altshuller referred to this as the “limbs” of the system)
    • Guidance and control of the tool
    1. Identify what changed in the example between the initial situation and the improved situation.
    2. Apply this finding to your problem—change the same element as the one that changed in the example.

The illustrations will guide you through this process.

Figure 1. Three of the many ways of analyzing the interactions in an inventive problem. IM Lab refers to the modeling illustrations used in the Invention Machine TechOptimizer™ and Invention Machine Lab ™ software.

Figure 2. A typical TRIZ example. In the original system, the object is the nail, the tool is the hammer, the source of energy is the person, the energy transmission mechanism is the hand and arm, the guidance and control come from the eye, brain and muscles of the person. The energy delivered to the nail by the hammer is mechanical. In the modified system, not shown, a pneumatic hammer is used to increase the power of the impact on the nail. Figure 3 shows the analysis worksheet.

Figure 3. Analysis worksheet for any problem where the example is the substitution of a pneumatic device for a human-powered mechanical device. Use of this worksheet will focus your attention on changing the energy source (a slug of metal still hits the nail, but it gets its power from a new source.) and will remind you that some changes in the transmission mechanism and the guidance and control might be needed if the energy source changes. The worksheet has been completed for the example of a bicycle, which is not powerful enough for carrying heavy loads uphill.


Example, start

Example, improved

My problem, start

My problem, improved








Pneumatic hammer


Modified bicycle

Energy source


Pneumatic device



Energy Transmission

Hand and arm

Pneumatic device, positioned by hand and arm



Guidance & control

Eyes, brain, muscles

Eyes, brain, muscles



The table suggest that I change the energy source, and possibly the energy interaction. Possible energy sources include small gasoline or propane motors, flywheel systems that store energy during the downhill motion, etc.

I invite other teachers of TRIZ and practioners of TRIZ to use this method of examining analogies, and to communicate your results to me, so that the method can be refined and used by all.