Identifying secondary problem

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IDENTIFYING SECONDARY PROBLEMS IN ENGINEERING SYSTEMS AT THE TRANSITIONAL STAGE OF THEIR EVOLUTION O. Abramov Introduction In this paper the methodology for identifying the most important secondary problems in Engineering Systems (ES) at their Transition-From-First-ToSecond Stage of evolution is described1. Normally, at this stage a laboratory prototype of an ES works just fine, with no obvious undesirable effects, while hidden undesirable effects have not yet manifest themselves. So, the main goal of the proposed methodology is to quickly and efficiently reveal critical secondary problems relating to the ES functionality in order to solve them rapidly and commercialize the ES as soon as possible. Broader objectives, e.g. identifying undesirable effects and problems that an ES may create at other stages of its life cycle, are beyond the scope of this methodology. The proposed methodology is based on the modified Failure Anticipation Analysis2 (FAA) methodology, which is part of the methodology for Comprehensive Analysis of an ES at the transitional stage of its evolution that was disclosed by the author in his thesis [4]. In contrast to the original FAA methodology [1-3], the proposed specialized methodology dramatically reduces the time required for analysis and guarantees that all critical undesirable effects and related secondary problems will be identified. These features make the proposed methodology applicable for use even in express-projects3. This is achieved by focusing the methodology on revealing only the undesirable effects that are related to the ES’s Main Function (MF) and by adapting the depth of analysis depending on how serious the analyzed undesirable effect is.

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Further in the paper “Transition-From-First-To-Second Stage” will be referred to as Transitional Stage. 2

Failure Anticipation Analysis as a methodology for revealing hidden undesirable effects in engineering system was first proposed by B. Zlotin and A. Zusman in papers [1-3]. 3

An express project is a short project with duration of approximately 2-3 weeks.

Types of Secondary Problems Identified by the Proposed Methodology Secondary problems that are aimed at eliminating ES’s hidden undesirable effects could be divided into several groups: 1. Problems aimed at improving the ES performance and functionality as well as at eliminating harmful effects that the ES may create when it performs its MF. 2. Problems aimed at circumventing the patent documents that may be infringed by manufacturing, selling and using the ES. 3. Problems aimed at improving the manufacturability of the ES and at reducing its cost. 4. Problems aimed at reducing the harmful effects that ES may create during its maintenance, recycling, etc. At the transitional stage of an ES evolution, the most important secondary problems are those falling in the 1st and 2nd groups because unless these are solved commercialization of the ES will not succeed, and, therefore, it makes no sense to commercialize it. Problems falling into the 3rd and 4th groups could be identified and solved later, either after the ES is commercialized or concurrently with commercialization of the ES. The methodology described here is intended to identify secondary problems related only to the 1st group. In order to identify problems falling into the 2nd group, the methodology for analysis of the intellectual property associated with an ES, disclosed in the thesis [4], could be employed. Brief Description of the Proposed Methodology A flowchart of the proposed methodology for identifying the most important secondary problems is shown in Fig.1. The methodology consists of the following stages: 1. Identification of the key hidden undesirable effects that may occur when the ES performs its MF (steps 1-4 on Fig.1). This ensures that non-trivial and “strong” secondary problems are identified. 2. Formulation and solving of key “inverted problems” and identification of possible scenarios how undesirable effects can occur (steps 5-7 on Fig.1). At this stage the amount of secondary problems is reduced by eliminating undesirable effects that are unlikely to occur. 3. Formulation of secondary problems as follows: “How to eliminate ‘Identified scenario of undesirable effects occurrence’?” (step 8 on Fig.1).

Initial information on ES

Tools to use: Step 1. Identification of ES’s MF and main technical parameters of this MF

Step 2. Identification of undesirable effects that may occur in the supersystem if the main parameters of ES’s MF deviate from their normal values

Step 3. Ranking of the identified undesirable effects based on how serious their implications are

GEN3 TRIZ MPV Analysis

"Classical FAA [1-3]" If needed• Component Analysis • Function Analysis • Flow Analysis (GEN3 TRIZ) Risk analysis

Step 4. Identification of the key undesirable effects

GEN3 TRIZ Cause and Effect Chain Analysis of undesirable effects

Step 5. Formulation of the key “inverted problems”

" Classical FAA"

Step 6. Analysis of working regimes of all standard components and ES test conditions

Regular engineering analysis

Step 7. Solving the key inverted problems. Identification of possible scenarios of undesirable effects occurrence

ARIZ, Standards and other TRIZ and GEN3 TRIZ solving tools

Step 8. Formulation of secondary problems aimed at eliminating those undesirable effects that may occur

End of Analysis: List of critical secondary problems

Fig.1. Flowchart of proposed methodology for identifying the most important secondary problems

Stages 1-2 (steps 1 through 7 on Fig.1) are the modified methodology of FAA, described in detail by the author in papers [4-5]. Stage 3 (step 8 on Fig.1) is not difficult to accomplish, as can be seen in the Example below. ____________________________________________________________ Example. During practical application of the proposed modified FAA for the analysis of the Hydrokeratome4, the following scenario of the most critical undesirable effect occurrence was identified [6]: "Water jet is suddenly blocked or deflected during the operation by a large particle that obstructed the water jet orifice. The consequences of this can be very severe - there is a big risk that the patient will lose his or her eye." Secondary problems aimed at eliminating this scenario could be formulated as follows: • How to eliminate the possibility of large particle penetration into the hydraulic system of the Hydrokeratome? • How to make it impossible for large particles that happen to appear in the Hydrokeratome's hydraulic system to penetrate the course and fine filters and reach the water jet orifice? • How to protect patient's eye from injury if the water jet orifice is obstructed by a large particle? After the corresponding inverted problems were solved (step 7), it turned out that the possibility of large particles penetrating the hydraulic system could not be completely eliminated. Also, it turned out that it is impossible to stop all large particles with course and fine filters. This means that of the three secondary problems formulated above, only the last one should remain in the final list of problems. ____________________________________________________________ In addition to illustrating the simplicity of Stage 3, this example also shows how efficiently the number of identified secondary problems decreases when employing the proposed methodology.

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Keratome is a device used in LASIK surgery to create a thin flap on the patient’s eye cornea prior to doing laser ablation. Hydrokeratome is a keratome utilizing a high-speed water jet to create the flap.

Practical Application of the Proposed Methodology The most important part of the proposed methodology for identifying secondary problems, namely - the modified methodology for FAA, has been successfully used by the author in a number of consulting projects. A comprehensive example of its practical application in the express-project on analysis of the Hydrokeratome is described in the papers [4, 6]. Application of the proposed methodology confirmed that it reliably reveals the most critical hidden undesirable effects and corresponding secondary problems aimed at eliminating them. The original FAA methodology in the same conditions normally reveals many more hidden undesirable effects, but most of them are not important for an ES at the Transitional Stage of evolution. Analysis of those unimportant undesirable effects, however, takes a lot of time and distracts the researcher from the truly serious problems. Application of the proposed methodology also showed its high efficiency: the time required for analysis using the proposed methodology is several times less than that of the original FAA methodology [1-3]. References 1. B. Zlotin, A. Zusman. Research Problems Solving. – Kishinev: MNTC “Progress”, “Kartya Moldavenyaske”, 1991 (in Russian) 2. B. Zlotin, A. Zusman. Methodology for Forecasting Failures, Harmful and Undesirable Effects (Experimental, Textbook). – Kishinev: MNTC “Progress”, 1991 (in Russian) http://metodolog.ru/00891/00891.html 3. S. Kaplan, S. Visnepolschi, B. Zlotin, A. Zusman. New Tools for Failure & Risk Analysis. Anticipatory Failure Determination (AFD) and the Theory of Scenario Structuring / Ideation International Inc., 1999, 2005. – USA: ISBN 1-928747-0-51 http://www.ideationtriz.com/new/materials/AFDNewToolsbook.pdf 4. O. Abramov. Failure Anticipation Analysis of Engineering Systems at the Transitional Stage of Their Evolution / Thesis for the Master's Degree in TRIZ. – St. Petersburg: 2011 (in Russian; abstract in English is available) http://www.triz-summit.ru/file.php/id/f5015/name/TRIZMaster%20Thesis_Abramov_79.pdf 5. O. Abramov. Application of Failure Anticipation Analysis in Engineering TRIZ-consulting / Three Generations of TRIZ / Proceedings of conference, October 25, 2003.- Regional public organization “TRIZPetersburg”. St. Petersburg: 2003, pp.104-110. (in Russian)

6. O. Abramov. Modified Algorithm for Failure Anticipation Analysis of Engineering Systems at the Transitional Stage of Their Evolution. Case Study / Proceedings of 3rd conference Материалы III “TRIZ. Practical application of methodological tools“. - Moscow:October 29, 2011.- pp. 6-11. http://www.metodolog.ru/node/1186