S-Fields & System Evolution
Editor | On 16, Jan 2018
Truth be told, I’m not the world’s biggest user of the S-Field tool. I find myself teaching it far more often than I am using it in anger. Partly, I think, because other tools have kind of superseded S-Fields, but perhaps, too, because it hasn’t had the benefit of being updated like most of the other parts of TRIZ now have. There is, of course, Iouri Belski’s ‘Improve Your Thinking’ book (Reference 1), but its job is mainly to attract people to what already exists rather than complement what existed in classical TRIZ with what exists in the rest of the world. In fairness to Belski, he has added some ‘intangible’ Fields to the story, but I’d have to say that any time I’ve tried to intrigue anyone other than engineers or chemists with S-Fields it has been an unmitigated sea of blank faces, and the thought of exposing Marketers strikes me as somewhat surreal.
It’s a pity because the S-Field way of thinking is very useful in the context of one of our themes of the year, ‘getting to the first principles’. In many ways the S-Field model is the ultimate version of first principles thinking, offering as it does the very definition of a minimum system.
I was running a short section of a workshop on S-Fields again the other week, which meant running a version of the ‘get the right number of good matches into the box’ case study – Figure 1. As usual, once given a list of the possible fields that could be used to achieve the required, everyone manages to configure a host of different solutions possibilities.
As usual, also, there was the inevitable debate at the end of the exercise regarding whether the ‘Classical TRIZ’ solution of adding ferromagnetic particles to the ignition compound in the tip of the good matches and using magnets was the best of the bunch. (Not to mention the frequent comment that seemingly every Classical TRIZ solution involves either ice or magnets!)
Part of the debate centres around whether matches are the best solution in the first place to the ultimate customer need of ‘making fire’, and another part focuses on whether the problem is actually the process that puts the ignition compound on to the head of the matches isn’t good enough and needs to be evolved. Both are perfectly legitimate points of discussion, but really aren’t anything to do with the exercise in its posed form. (By the way, I never cease to be amazed by peoples’ willingness to explore the problem at other hierarchical levels when it isn’t their own, but point-blank refuse to do the same thing when it is their own problem!)
So, once we get over this phase and recognize that we’re forcing ourselves to solve the problem at the initial level, we can finally get to the issue of why magnetism is better than centrifugal, mechanical (usually some kind of grid system where the bad matches fall through) or any other kind of field. How might the S-Field tool really help in this kind of situation?
The problem is about getting the right number of good matches into the box. In order to achieve this goal, four sub-functions are required:
- Detect bad matches
- Separate bad matches
- Detect the right number of good matches
- Place the good matches in the box
Each of these functions ‘demands’ the existence of a complete S-Field model. In which case, we potentially need to find four substances and four fields:
In the light of this potential need, the attractiveness of the ferromagnetic particles solution starts to become apparent: By choosing a magnet of the right size to pick up the right number of matches, we can effectively end up with one S-Field model to achieve all of the required functions – Figure 3:
- Belski, I., ‘Improve Your Thinking: Substance-Field Analysis’, www.triz4u.com.