Technical problem solution synthesis based on the ideal type method.

Belak, Stipe ; Covo, Petar ; Belak, Ana 等

Abstract: The paper deals with the complex system design as a result of technical problem solution. The problem solution is defined as technical complex system synthesis. The solution is considered as a result of function integration process that starts on the basis of zero solution that consists of particular functional claims that could be fulfilled using the single element or sub system of higher grade. The function integration process aiming to the technical system synthesis is not executable without the inter-objectives definition. To preserve the close connection between the problem claims and the system/subsystems/elements function integration process execution the scientific Ideal Type Method is used. The Ideal Type Method is modified for technical design purpose, and some of possible ideal types and their impacts to the system synthesis are briefly noted. Readers are directed to suggested references as examples to the method.

Key words: ideal, type, system, synthesis.

1. INTRODUCTION

The first aim of this paper is to introduce the Ideal Type Method in technical designer's practice. To serve this intention some, the most frequent performances are defined as ideal types and their expected impacts to the technical system design or technical problem solution is indicated. Term technical problem, in this paper, is certain description, list of claims or both of them to one or more functional or other performances that should be fulfilled by the problem solution. Technical problem solution procedure consists of the problem function claims (expected function of the technical system as a solution to the problem) analysis part and the system synthesis part. The Ideal Type Method is meant to be the aid and handy tool in the process of the technical system synthesis.

The problem analysis is based on the problem defined function analysis and solution synthesis called Function Optimization Method presented in the paper (Belak, 1991). Technical problem solution, in this paper is considered as the complex technical system. The Method consists of structured analysis procedures of the problem as entity, aiming to the function required by the problem definition, definition and functional analysis of sub problems of the first grade, definition and functional analysis of sub problems of the second grade, sub problems of the third grade continuing the analysis further to single function stage. The stage of the single function definition means the zero solution (initial solution) of the problem enabling the synthesis of the complex system initial design as the problem solution. The solution synthesis procedure is, in principle, very simple but in real design practice, particularly in complex system design, it becomes very complex even in the first step of function integration.

The Functional Optimization Method is presented in the paper (Belak, 1991) on the basis of outline theoretical model of technical problem analysis and technical system solution integration. The Functional Optimization Method application on the scientific research is done in the reference (Belak, 1990) and on designer practice is done in references (Belak et al., 1993; Belak et al., 1994; Belak, 1996).

2. THE METHOD

Ideal Type Method is one of scientific research methods. The Method, by definition, is use of two opposite extreme models of the possible solution based on the particular or multiple performance or qualities. The method is used to identify the span of values that should be explored. In every day life one usually use the Ideal Type Method instinctively every time when is trying to define the best and the worst scenario of future events or results, so designer's logics, in different ways, contains certain influence of the ideal type method, that depends on the designer's personality and experience. In designer practice ideal type does not have the same meaning as in science. Ideal type that is used in designer practice means the upper and lower limit of the span containing all values or models that are of interest for designing process. That encounters existence of the possible scope of certain quality (performance) that can be considered as minimal or as maximal value of the quality or performance. In the scientific research planning and preparation the Ideal Type Method is mainly used for the research span framing defining the variables value planned range or defining the variables acceptable value limits. Particular value of the Ideal Type Method in designer's practice appears in the system solution synthesis stage (Belak, 1991), when the system elements (subsystems) function integration takes place. Ideal Type Method application to technical system design or technical problem solution, as presented in paper (Belak, 1991) cannot be applied directly. That is caused by the fact that the subsystem or technical sub problem extreme value or performance is not explicitly present in the system or problem solution overall performance.

3. IDEAL TYPES

The technical problem solution starts, (Belak, 1991) on the basis of the problem zero solution consisting of elements (sub systems or particular solutions) that completely serve only one function or claim. In the case that technical problem describes technical system as a solution to the problem, the solution system is defined mainly through the system overall working performances whatever they could be and system service overall life cycle costs. Two, very important system solution characteristics, though cannot be used in the Ideal Type Method, and should be analyzed using techniques and methods of Terotechnology or Life Cycle Cost (Belak, 2004; Belak/Ticin-Sain, 2005). The system overall working performance is always considered as lower limit, but it is not necessarily a basis for ideal type definition. Thus, the overall working performances should be omitted in the ideal type method use, and can be used in definition of the system terotechnological efficiency (Belak, 2006). The system life cycle cost also should not be considered as a basis for ideal type definition because the opposite ideal type is meaningless (Belak/Cicin-Sain, 2005; Belak, 2006). However, characteristics of possible system/subsystem, that represents technical problem solution, are numerous and very applicable in the system design. The purpose of this paper is, to briefly discuss those characteristics in the case of application Ideal Type Method in the technical complex system design. Some of these characteristics, very frequently occurred in technical designers practice are, for example, the system production cost, application of international standards (ISO), and application of particular, local, branch (internal) standards, degree of effectiveness (availability, adaptability, reliability), required degree of maintainability, recyclability, required degree of intermodal and modular use, possibility of upgrading and working performances increment, functional safety and quality, environment friendliness and future ecological claims receptiveness.

The system production cost as a part of the system life cycle cost is the characteristics that should be applied to the system design. However, the system production cost should be used as an ideal type in two forms. The first form is defining the ideal types on the basis of lower and upper production cost. The second form is defining the ideal types on the basis of the one product cost as the system synthetic quality. The ideal types defined on the basis of applied standards (international or other) express the degree of applied standardization. The applied standardization degree, for mass produced system, realizes moderate impact to maintainability (improving the system maintainability) and very strong impact to the system per unit production cost (increasing production cost). The system production amount decrement impacts the possibility of standardization degree application (the standardization possibility increases).

Without the system elements function integration (one or more system elements can perform two or more functions what means that the elements integrate more functions acting in synergistic way), application of standardized elements, will increase the system production cost per unit reasonably and even strongly but keeping convenient maintainability. The system ideal type based on the defined service availability strongly depends on the system achieved maintainability and modularity. The system availability degree increment increases the production cost strongly. The system ideal type based on the defined service reliability strongly depends on the system topology. The system reliability degree increment increases the production cost strongly. The ideal types defined on the basis of modularity degree indicate the strong impact to the system topology, production cost (increasing it significantly), very strong impact to the system service availability (increment), service reliability (moderate decrement), system survivability (increment) and maintainability (increment). From the problem solution synthesis point of view, all requirements to the solution performances i.e. system design, could be divided into following main groups:

Topological requirements that define the system structure, aiming to ensure acceptable degree of system reliability, system survivability (toughness), system modular use and system upgrading possibilities; Requirements on the system maintainability degree affecting strongly on the system morphology and depending on the applied standards degree; The system production requirements that define production technology, production capacities and availability of technological procedures. Environment friendly system design affects the system safety performance degree, recyclability and future ecological claims receptiveness. After this brief analysis one dilemma appears. Should one define ideal system types using particular requirements as defined in technical problem definition or using main groups of requirements to the problem solution (technical system design)? The first choice, ideal type definition using particular requirements, in the case of numerous requirements, can direct the procedure to the Simulation Method especially in case when requirements describe continuous variables or values. The second choice is more designer friendly, but more complex in ideal type definition and presumes more experienced designer and higher designer's level as well. Thus the particular performance ideal types are convenient and should be used in the technical system detail design phase while the synthetic based ideal types are more convenient and should be applied in the preliminary and outline design phase.

4. CONCLUSION

The Ideal Type Method is briefly introduced into the technical designer's practice logic as an aid and handy tool in the process of the technical system synthesis according to the Function Optimization Method. Some, the most frequent basis to ideal types definition (production cost, application of international standards, application of particular, local, branch standards, required degree of effectiveness consisting of availability, adaptability and reliability, required degree of maintainability, required degree of recyclability, required degree of intermodal and modular use, possibility of upgrading and in service working performances increment, functional safety and quality, environment friendliness and future ecological claims receptiveness) are indicated along with their impact to the system synthesis as well. Two kinds of ideal types, particular and synthetic and their applicability are noted.

5. REFERENCES:

Belak S., (1990) Mogucnost primjene valjnih lezaja u integralnoj izvedbi tarnih planetarnih prijenosnika, doktorska disertacija, Fakultet strojarstva i brodogradnje Sveuciliste u Zagrebu; Integral design of frictional planetary reducers Ph. D. Thesis, FSB, University of Zagreb, Zagreb.

Belak, S., (1991) The Method of Analysis and Synthesis for the Solution of the Technical Problem, Proc. of the XI SYM-OP-IS, Beograd.

Belak S., (1993) Design of the submachine guns family BM2K, BM2L, (cal. 9x19mm, cad.1100/1600r/min); Bagat PPM, Zadar.

Belak S., (1994) Design of the submachine guns family B5R (cal. 9x19mm, cad. 800/1400 r/min, system Robinson); Bagat PPM, Zadar.

Belak, S., (1996) The Synthesis of the Combined Bolt Design Solution for Blowback Operated Automatic Weapons", Proc. of the 4th Symposium Design '96, Opatija.

Belak, S., Covo, P., (1998) Design for Maintenance, Euromaintenance '98, Proc. of the 14th European Maintenance Conference, Dubrovnik.

Belak, S., (2004) Terotechnology, Proceedings of OCEANS'04 MTS/IEEE/TECHNO- OCEAN'04, Kobe, Japan.

Belak, S., Cicin-Sain, D., (2005) Komparativna analiza upravljanja proizvodnim kapacitetom, terotehnologije i LCC sa stajalista troskova, Zbornik radova 11. medunarodnog savjetovanja HDO, Comparative Analysis of the Production Facility Management from the Point of Service Cost According to Terotechnology and LCC, Proc. of the 11th International Symposium HDO, Sibenik.

Belak, S., (2006) Terotechnology, book ,(in Croatian), VSTM, Sibenik.