Analysis of a problem situation and choising the levelof the problem being solved
Laboratory " Ukraine TRIZ-education"
The analysis of the initial situation and the choice of the direction of solving of the problem is the hardest part of solving technical problems. Algorithm of G. S. Altshuller - ARIZ-85B offers to start looking to the solution from the "lowest (minimal) level" - through changing of the subsystem. In this instance, the choice of the solution is already set on the first step ARIZ-85B, but the existing rules of analysis don't allow for the possibility of making a clear choice.
following work it is shown that during the analysis of the problem situation,
choice of solution of the problem being solved is set by formulating of the
requirements of the system, determining the Primary Function of system, choosing the
Principle of Operation of the system and elements, that create the system
effect and guarantee execution of the Primary
During the analysis of a problem situation, choosing the level of the problem being solved is founded on formulating the requirements of the system, defining the Primary Function of the system, choosing the Principle of Operation system and elements, which create the system effect and guarantee execution of the Primary Function.
During the analysis of the problem situation and search for the solution using the ARIZ-85B algorithm, the main goal of the first part is defined as "going from vague (ill-defined) invention situation to a clear-cut (distinct) built and maximum simple scheme of the problem". The emphasis is on solving the mini-problem, when "everything is leaving unchanged or simplifies" (1), where "everything" means only the Primary Function of the system and the composition of the system: the set of the elements that creates the system effect and allows for the realization of the established Principle of Operation.
However, solving of practically every problem formulated as mini-problem, leads with few rare exceptions to changing the composition of the system, including the operating organ, which in turn often leads to changing the Principle of Operation of the system -- that is, it leads to solving Maxi-problem of different levels. At the same time the question is still open: on which stage of solving and how does this 'transition' happen?
It is presumed, that the selection of the solution is already set on the first step of ARIZ-85B -- during the analysis of the initial situation, but under the existing rules of analysis making the exact choice is impossible. In the algorithm AVIZ-2000\p\ (2) under the analysis of the initial situation three parts are allotted, although even they don't allow for choosing the level of the problem being solved, which can be clearly seen on the examples.
Thus, while solving the problem #3 "Painting the product":
- <Painting the product> is specified as the Primary Function, although the float with contacts is only necessary for turning the pump on and off;
- The composition of the system and the principle of it's action is not specified;
- The overflow of paint from the bath is for some reason considered an element of solving the main function (2, c.40).
The offered solutions have a various level as well:
- From outwardly simple "The incoming stream of the paint removes a layer of dry pigment itself from the surface of the float",
- Through a whole row of alternatives (in which the float doesn't exist at all),
- To changing of the way the detail is suspended, using Archimedes's law.
The experience of solving a whole row of problems allows presuming that that level of changes, which will be necessary to input in the system, can already be identified on the first stage of analysis of the situation during the formulation of the Primary Function of system, it's the Principle of Operation and, accordingly, composition of elements.
Let's show this on an example of analysis of the previously mentioned "Painting the product" problem. Briefly, the essence of the problem is the following: the pipeline with the detail lowers over the bath with paint and sinks the detail into the bath with paint. In order to compensate of an expense of paint a pump is installed for replenishment. The control over the pump is carried out by the float, which through the lever acts on the contacts. However the paint sticks to the float, and it becomes heavier and sinks, not switching the pump off at the maximum level of paint. What do we do?
The solution of any problem on modernization of the system starts (Step 1 ASPS -- Algorithm of Solving of Problem Situations) with the analysis of situation: formulating the Primary Function of system, it's Principle of Operation and identifying of the main elements (3). Here there might be various options:
a) In order for the level of the paint in the bath to fall within the range <no more and no less>, it is necessary for the float to also swing in that range exactly corresponding with the level of paint. If this condition is met, the system will function normally and will guarantee the necessary level being supported through timely switch on and off of the pump. Then the Step 1 can be formulated as:
1a. Technical system for IDENTIFYING of the maximum and minimum levels of paint in the bath through IDENTIFYING the position of the float consists of the bath, paint, float, switch, and contacts relay.
b) The Primary Function, it's Principle of Operation and the composition of the system can be viewed somewhat more generally:
1b. Technical system for SUPPORT of the necessary level of paint in the given range in the bath through REPLENISHMENT BY THE PUMP consists of the bath, barrel of paint, float, contacts relay, pump, and pipes.
c) More generally:
1c. Technical system for SUPPORT of the necessary level of paint in given range in the bath through it being FED into the bath consists of the bath, barrel of paint, pump and pipes.
d) Much more generally:
1d. Technical system for COATING of the outward surface of the detail through COMPLETELY SUBMERGING it in the paint consists of the pipeline, hook, detail, and the bath with the paint.
e) And the most general:
1e. Technical system for COVERING of the outward surface of the detail through COATING it with paint consists of the detail and the paint. (As indicated above, this is exactly how the problem is formulated in (2).)
And now let's analyze, which possibilities are offered by each formulating, which Harmful Effects appear with each variant, and which changes in the system are necessary in order to guarantee it's functioning normally and avoid the overflow of paint from the bath.
Let's begin with the last variant -- the most general. Expression < for COVERING of the outward surface of the detail through COATING it with paint> doesn't say anything of the METHOD of covering with the paint. And there are several such methods. And it's completely obvious, that if we will be painting the outside surface with, for example, a pulverizer or a brush, then there will be no necessity in having a bath, and the problem of supporting the level of paint would be eliminated. Although, this solution calls for a serious negative effect: necessity of changing all of the technology and rebuilding of the shop. This solution for the existing technology is on the level of Higher-level system (Supersystem).
<COWERING the outward surface of the detail through COMPLETELY SUBMERGING it into the paint> (variant <d>) - one of the methods of painting the details, also the simplest one. The Harmful Effect, which crops up here is clearly specified in the situation: as the paint is used up the detail is not submerged completely into the paint. A rather realistic problem appears: completely submerge the detail into the paint depending on the level of paint. Changes, which will become necessary, will mainly concern the pipeline and the bath.
Variant "c" - in order to SUPPORT of the necessary level of paint in given range in the bath through it being FED into the bath -- nothing is said about the WAY to feed the paint. The simplest of them is letting paint flow by gravity from the barrel, at the same time the volume of the fed paint can be easily synchronized with the speed of movement of the pipeline and the amount that's used up to cover the detail. And even opening and closing of the barrel can be controlled by the turning on and turning off of the pipeline... That way the float is not even necessary... There are other ways...
Variant 'b' - < for SUPPORT of the given range of the necessary level of paint in the bath through FEEDING BY THE PUMP> already necessitates, not touching the pipeline and the detail, some kind of device for turning on and turning off of the pipeline. The float here is ONE THE OF THE AVAILABLE VARIANTS of such a device. The unreliability of such method of turning on/off is the Harmful Effect.
In the variant 'a' the available solutions affect only contacting with each other float and paint: here the Harmful Effect - the paint sticking to the float and the change of it's weight, which leads to the false shorting of the contacts and turning off of the pump.
The five alternative ways of formulating the Step 1 define the levels of possible changes and, hence, the hierarchy of problems. The conducted analysis shows that already on the first stage of analysis of the situation the choice of the Primary Function of the system, it's the Principle of Operation and, accordingly, its composition decides that level of changes that will become necessary to introduce to the system in order to eliminate the occurring of the Harmful Effect. These changes, which touch only the subsystem (for each given system), are minimal, in this case the system <doesn't notice> them and the Principle of it's Operation is not changed. Therefore it's better, having analyzed the situation and having discovered the hierarchy of the problems, to start at the lowest level. And only having made sure that all of the resources of the elements are used and that the system has reached it's limitations to go to the higher level and change the existing Principle of Operation.
Let's sum up the analysis.
In the variant 'a', the Primary Function is declared as the determining of the level of paint, and the Principle of Operation is chosen to be the manipulation of the float on the contacts through the lever. Therefore in each of the possible solutions the float and the lever for switching of the contacts are left. In order to introduce these solutions, it's necessary to complete minimal changes. These changes incidentally, under the classification of G. S. Altshuller, make up the group of solutions of the first level.
In the scenario <b>, the Primary Function is declared as the support of the necessary level of paint inside the given range, and the Principle of Operation -- is the method: through FEEDING IT BY THE PUMP. Here the changes will be more crucial. They will not touch the Principle of Operation system -- it's turning on of the pump with the help of contacts, but they will change the method of manipulate the contacts (solution of second level).
In the variant <c> a new system is synthesized, the Primary Function of which is to guarantee support of the necessary level of paint, while the method of feeding of paint is declared generally -- by a pump. Therefore, it will be necessary to find the Principle of Operation for the whole system of control. When the problem is stated like this, the auxiliary function is done not only by the float and the contacts, but also by the pump. Theoretically this is a solution of the third level, but the scale of the problem being solved is closer to the second level.
In the variant <d> offers in essence the Principle of Operation of the system (completely submerging the detail into the paint), which guarantees the realization of the Primary Function -- covering the outward surface. Here the support of the necessary level of paint in the bath is viewed as the problem, which has to be solved in order for the Primary Function to be carried out the best possible way. As a whole, the solution of this problem is on the third level.
Variant <e> defines the necessity -- protect the outward surface of the detail -- and poses the problem (formulates the Primary Function) in the most general form: through coating the detail with paint. And the problems appear when we choose the Principle of Operation of this system and start choosing the elements, which guarantee the carrying out of the Primary Function. The level of solution -- third or fourth -- will depend on the choice of the Principle of Operation.
The choice of level of the problem being solved (including in the time of the synthesis of the new system), therefore is already set:
- While formulation the requirements of the system and the Primary Function, which realizes this need?
- While choosing the Principle of Operation of the system and elements, which while carrying out the auxiliary functions create the system effect and guarantee the realization of the Primary Function of the whole system
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Mark Meerovich born in 1941
TRIZ Expert (18 years experience).
Master of TRIZ (qualified by Genrich Altshuller). Master of Science in Engineering.
Professor (logistics, project management) at the ChOUEHS, Odessa, Ukraine and leader of the Scientific-practical Laboratory "Ukraine TRIZ-education" (ChOUEHS, Odessa, Ukraine).
TRIZ experience: 18 years experience in problem solving management (research problem, manufactures problems, management problems etc.). Large experience in TRIZ education (more than 80 seminars). Former students: engineers, researchers, managers, children, and schoolteachers.
Area of scientific interests: Technology of forming creative thinking and "Cutting-edge pedagogic" that develops characteristic of a creative individual in students.
More than 20 publications and 3 books (on technology of developing of creative thinking).