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TRIZ

TRIZ is based on finding ways to resolve contradictions in designs and products. This is a very brief introduction.

Background

TRIZ was invented by Genrich Altschuller, a Russian patent clerk. He noticed that many patents were solving very similar generic problems. Eventually, he analyzed over 200,000 patents and noted that most inventions were about solving contradictions, and that most solutions could be classified into 40 categories.

Overview

Begin with a crisp list of the primary functions of a product. A primary function is one that is fundamental to the use or operation of the product.

Anything that doesn't contribute to at least one of the primary functions of a product is considered harmful — that is, it detracts from the effectiveness or efficiency of the product.

Most things are in some way harmful. For instance, the engine of a car definitely contributes to a primary function, but it also makes the car heavy, can take up alot of valuable space, and creates toxic fumes.

The goal of TRIZ is to remove the harmful elements of a design and leave only the beneficial ones.

TRIZ often refers to the ideal product — a product that has zero harm. Of course, this isn't possible. But ideals are good because they provide fairly stable goals against which you can measure progress.

So it is often a good exercise in TRIZ to start by defining the ideal product. For example, an ideal car might have zero mass and infinite power.

Now step back a little from this ideal. The inertial weight of the engine lowers the car's acceleration. How can one offset the inertial weight of the engine? (Star Trek-like inertial dampers are not a legitimate solution; but flywheels could be.)

In this case, we have what is called a contradiction. We want to lower the inertial weight of the engine, to improve acceleration. But this means a smaller engine, which can't deliver enough power to provide the acceleration we want.

A TRIZ contradiction consists of two features, aspects, or characteristics of a product that work against each other, as the car engine example shows. One characteristic is a good one, and the other is harmful.

TRIZ has a standard list of things that can contradict each other. This list is widely available on the web; two good URLs are:

Once you have identified the contradicting items, you can look up TRIZ principles that address the contradiction. Generally, the contradictions are as pairs of numbers (the numbers of the items in the list of contradictions). The principles are arranged to show which contradictory pairs they address.

Again, this is readily available information. Here are some good URLs.

  • At CreatingMinds.org, the full matrix is broken into three pages: 1, 2, and 3.
  • The numbers in the cells are the ID numbers of the corresponding TRIZ principles.
  • At triz40.com, the full matrix is available.

The principles themselves are available at triz40.com, and at CreatingMinds.org.

A very interesting tutorial on segmentation, inversion, and prior action is available.

A quick example:

In our car engine example, the contradicting items are weight of moving object (#1) and speed (#9).

Looking at triz40.com's contradiction matrix, we find in (row 9, column 1) the numbers 2, 13, 28, and 38. These are the IDs of 4 principles that can help us resolve the contradiction, namely extraction, inversion, replacement of a mechanical system, and strong oxidants.

Of course, none of these principles just give us the right answer for our problem. They do, however, suggest things that can, with enough thought and study, lead to an interesting new possibility.

This is, of course, only the most introductory description of TRIZ. There are many other TRIZ related web sites easily accessed by Google.

Points of interest

design/triz.txt · Last modified: 2020.03.12 13:30 (external edit)