# 1.7.2 Contradiction Matrix - HOW TO USE IT (2)

*Using the Matrix*

** With TRIZ we uncover conﬂicts**, and then solve contradictions with the 40 Principles: to solve a technical contradiction we use the matrix to separate the links between two parameters. Of all the TRIZ tools, beginners ﬁnd the power of the Contradiction Matrix the easiest to understand and the hardest to actually use. This is because once we have uncovered our contradiction

**(and the things that consequently get worse) with the 39 Technical Parameters.**

__we cannot see how to match the things we ’ ve got to improve__**and each example had to be reduced to its simplest, most general term. In the list of 39 Technical Parameters at the back of this book we describe what each one means and give some synonyms to help in this difﬁcult and unfamiliar task. As in all difﬁcult tasks we have to practice until we succeed and keep practising until it becomes a little easier (this step is always challenging even when we are experienced TRIZ practitioners). One way of making it simpler is not to try and ﬁnd the perfect exact contradiction but**

__The 39 Technical Parameters are derived from the patent database__**Try several similar contradictions and see which principles are suggested – and when w**

__try several that approximate to our contradiction.__**then these principles are a good place to start and probably offer powerful solutions to our problem.**

__e get some principles occurring more than once,__** Sometimes special care is needed and we cannot assume always to understand what the Technical Parameters mean just from their titles. **For example, 27. Reliability is deﬁned as: ‘ A system’s ability to perform its intended functions in predictable ways and conditions. ’ This means predictability and not necessarily a certain robustness which is sometimes assumed in the term reliable.

For some problems this mapping of real-world descriptions of a problem onto the 39 Technical Parameters used by the matrix can be a little tricky: the Technical Parameters are very general, and a certain amount of thought and careful consideration may be necessary to map the speciﬁc ‘ real world ’ problem parameters to the matrix general Technical Parameters. Understanding which beneﬁt is the most important is a powerful starting point for ﬁnding the really relevant solutions. In the dancing lady cartoon below we assume that strength is the really important beneﬁt she wants and the loss of lightness is a problem. Essentially she needs to make the table stronger, but she doesn’t want it to subsequently get heavier .

The Contradiction Matrix can be used for many different kinds of problems. ** To successfully use the matrix we have to match the solution to our problem to the 39 Technical Parameters** and

**– which Technical Parameter is adversely affected? So when we design a table to be stronger, our question might be: how can we get the strength we want without increasing weight?**

__we then have to ask the right question: when I apply this solution (such as improving strength) what then gets worse__The matrix contains all the answers of how to solve the Technical Contradiction – how to get more strength without increasing weight. Using the Contradiction Matrix to identify which TRIZ Principles show us how to get strength without increasing weight suggests the following solution triggers:

40 Composite Materials

26 Copying

27 Cheap Short - Living Object

1 Segmentation

To understand and apply the suggested solutions from the triggers we are given we also have to ask: __what are all the beneﬁts (functions) we want from the system? And what is the priority of those beneﬁ ts?__

**40 Composite Materials ** suggests using a strong but light material and together with the trigger of Segmentation might suggest how to save weight by only putting strength where we need it.

**27 Cheap Short - Living Object** suggests something like a cardboard box – which assumes that durability is not a requirement. We need to understand all the requirements of our system (and the priority of beneﬁts) to judge whether this is an appropriate solution or not.

**26 Copying **suggests that we replace a strong and heavy material with one which is strong but lighter. We might use a material that looks like wood but is actually a stronger copy material. This principle suggests that we copy the heavy material with one which gives us the strength we need but has a more appropriate weight. Another example of using this principle copying would be in testing something like a drill which is to be used in remote areas of inaccessible and very hard rock. The tests could be on a copy of rock – artiﬁcial rock which simulates natural rock in terms of strength in that it loads the drill with high torque, but could be made of a much lighter composite material which is more easily avail- able than remote rock and easier to handle. Or even copying could mean that we use a video of our lady dancing instead of putting the strain on a small table.

**1 Segmentation **represents most of the modern design of tables today: segmented tops for different sizes; segmented table legs for ease of manufacture and assembly; segmented joining of different materials for extra strength. TRIZ links solutions from the 40 Principles (answers/solution triggers) to the right questions when we use the Prism of TRIZ below:

TRIZ for Engineers: Enabling Inventive Problem Solving, First Edition. Karen Gadd.

© 2011 John Wiley & Sons, Ltd. Published 2011 by John Wiley & Sons, Ltd. ISBN: 978-0-470-74188-7