Engineering (technical) contradiction

Engineering contradiction (EC), also called technical contradictions (TC), is a parametric model of the problem in which an attempt to improve one parameter of the engineering system leads to worsening of another parameter.

Overview

When solving key problems, methods or technologies are often used that, while improving a specific parameter of a technical system, simultaneously lead to the deterioration of another parameter.

Modeling such a situation as an engineering contradiction is the first step toward solving the problem in a way that not only improves the first parameter but also avoids worsening – or even potentially improves – the second parameter as well.

Models of solutions for engineering contradictions are inventive principles. The tool that is used to translate the engineering contradiction into inventive principles is contradiction matrix also referred to as Althuller matrix.

Formulating the engineering contradiction

An engineering contradiction should be formulated using the IF-THEN-BUT format. That formula provides two parameters that constitute the engineering contradiction for solving:

in the line THEN, the parameter that has to be improved to resolve the problem,
in the line BUT, the parameter that deteriorates when the technique / approach mentioned in line IF is applied.

To properly formulate a contradiction, it is helpful to follow a specific order of providing the information. Typically, we start with the THEN position, then proceed to IF, and finish with BUT. The red numbers in the picture above indicate the order of filling.

Let us consider a simple example of a key problem: the table is not strong enough. One way to strengthen it might be by adding additional reinforcing elements, but these increase its weight. The engineering contradiction will be formulated as follows:

Usually, a key problem can be modeled using more than one engineering contradiction. This is typically due to the fact that various technologies can traditionally be applied to solve the problem.

For each technology, action, parameter, etc., proposed in the IF row, a separate contradiction should be created.

For example, to solve the problem of a weak table, various approaches can be applied: using a stronger material, increasing the thickness of the tabletop, or shaping it into a slightly domed form. Each of these approaches has its own implications, often leading to the deterioration of another parameter. Therefore, a technical contradiction should be formulated for each approach.

Alternative engineering contradiction

For each engineering contradiction, an alternative (opposite or inverted) one can be formulated. The following example presents a procedure for creating it:

The alternative contradiction should contain the same parameters as the base one, but the problem it models is different. Since the contradiction matrix is not symmetrical, the inverted engineering contradiction supports generating more ideas and can lead to solutions that help to achieve the goal of the project. It is also very helpful in formulating the physical contradiction.

The algorithm for an engineering contradiction

An algorithm to deal with the engineering contradiction is the following:

Articles

Contradiction matrix
- Typical parameters