System Design Engineering of Technical Products KKS/ZKMA b_ZKMA/… Pilsen, Czech Republic, 2014 Department of Machine Design 1 Prof. Dr.-Ing. Stanislav Hosnedl Sylabuses to Lectures – Part A4
A4 TS Properties - TS object/topological aspects - TS object/topological aspects SYSTEM DESIGN ENGINEERING OF TECHNICAL PRODUCTS INFORMATIVE NEEDED IMPORTANT ADDITIONAL 2
TS property is, when … ? A4 TS Properties - TS object/topological aspects - TS object/topological aspects TS(s) LIFE CYCLE STAGES FOCUSED ON THE RESPECTIVE TRANSFORMATIONSDEFINITION of TS PROPERTIES 3 © S. Hosnedl, University of West Bohemia, Pilsen, Czech Republic
TS Properties, Attributes, … There are many synonymous for the phenomenon Technical System/Product Property which are also being used e.g. attribute, indicator, (design) parameter, (distinguishing) feature, quality, power, performance, etc.. It will be outlined in the presented paper that the consistent use of the term TS property has its advantages both in theory and in practical use. Here a TS property will be understood as “any attribute or Indicator of a system: performance, form size, colour, stability, life, manufacturability, transportability, suitability for storage, structure, etc. Each Technical System is a carrier of all properties, and their totality represents the value (comments of authors: i.e. total quality) of the system” [Hubka 1980, p. 64]. It is obvious that a TS property is a cumulative criterion, i.e. (not elemental) TS Indicator from a more general nevertheless specific “reasonable” viewpoint. TS(s) LIFE CYCLE STAGES FOCUSED ON THE RESPECTIVE TRANSFORMATIONSDEFINITION of TS PROPERTIES 4 NEEDED A4 TS Properties - TS object aspects - TS object aspects
Inherent and Assigned TS Properties TS Property can be understood according to [CSN EN ISO 2002, art ] a distinguishing Indicator/feature of a (technical) product/ system, which can be: - inherent, i.e. “existing in”, especially as a permanent ‘inborn’ property (e.g. form, dimension, material, production cost ) - assigned, i.e. “existing out”, especially as an impermanent ‘artificial’ property (e.g. price, owner ) It is obvious that design engineering of TS generally deals only with the inherent TS Properties. Thus the adjective ‘inherent’ is understood implicitly when speaking about TS properties. TS(s) LIFE CYCLE STAGES FOCUSED ON THE RESPECTIVE TRANSFORMATIONSDEFINITION of TS PROPERTIES 5 NEEDED A4 TS Properties - TS object/topological aspects - TS object/topological aspects
Property Indicators ? Dimensions of Property Indicators? Values of Property Indicators ? TS(s) LIFE CYCLE STAGES FOCUSED ON THE RESPECTIVE TRANSFORMATIONSPROPERTY INDICARORS and their VALUES 6 © S. Hosnedl, University of West Bohemia, Pilsen, Czech Republic A4 TS Properties - TS object/topological aspects - TS object/topological aspects
TS Property Indicators TS property of any kind is characterized by a set of measurable (not necessarily according to a numerical scale) elemental criteria (from 1 to n) which enable any TS Property to be specified, measured, compared, evaluated, etc. The author of the document call these criteria TS ‘Property Indicators’ and have very good experience with its use in many theoretical and practical fields of design engineering, some of which will be introduced in the presentation at the workshop. These TS Property Indicators can be: either intuitively assigned established according to experience, intuition, availability, etc., (e.g. TS appearance according to the ratio of main dimensions, compatibility of the used colours, etc.) or normatively stated defined by laws, standards, etc., (e.g. TS (car) safety according to the strictly defined crash deformations, deceleration, space, etc. Indicators). TS(s) LIFE CYCLE STAGES FOCUSED ON THE RESPECTIVE TRANSFORMATIONSPROPERTY INDICARORS and their VALUES 7 NEEDED A4 TS Properties - TS object/topological aspects - TS object/topological aspects
TS Property Indicators Any TS property is specified by (agreed or normative) set of its ‘Manifestations’ (English) or ‘Ausprägungen’ (German) [Eder 2008]. However, these terms have not any suitable equivalent in Czech, and the use one of them in original without translation (as often used in case of English) is not obviously suitable in this case. Thus we will aptly call these ways of “specifications of properties” in Czech as TS ‘Property Indicators’, for the sake of more simple translations, and for full compatibility with real life. Notes: - For example, in case of a cube, these “property indicators” are length, width and height. In case of sphere, the only one “property indicator” is diameter, etc. -If the property is fully characterized by the only one “property indicator”, the terms “property” and “property indicator” may overlap. However, it is useful to distinguish these two terms in general. TS(s) LIFE CYCLE STAGES FOCUSED ON THE RESPECTIVE TRANSFORMATIONSPROPERTY INDICARORS and their DIMENSIONS 8 NEEDED A4 TS Properties - TS object/topological aspects - TS object/topological aspects
Scales for Dimensions of TS Property indicators TS Property indicator of any kind can be specified and “measured” by its one (direct) or more (indirect/auxiliary/reference i.e. “coordinate“) “Dimensions” (in its wider viewpoint, i.e. measurable not only numerically) i.e. “Variables”. Note: -For example a length of an TS edge can be directly specified by one dimension, or indirectly by the vector differences of two or three dimensional coordinates of relevant initial and end points; further example is a form of complicated TS surface area, which can be e.g. specified by a set of three dimensional coordinates i.e. by set of trios of dimensions”. “Dimensions”/“Variables” of a TS Property indicator, can be classified in terms of their measure scales, e.g. according to [Ackoff 1962] and [Pons 2001] as follows: - Continuous (Quantitative) Scales (incl. corresponding Dimensions/Variables): = ratio (numerical) (e.g. length, weight, duration, absolute temperature) = interval (numerical) (e.g. relative temperature, relative time) - Ordinal (Qualitative) Scales (incl. corresponding Dimensions/Variables): = numerical (e.g. Mohs scale of mineral hardness) = textual (or weak order) (e.g. “warm, hot “grades for academic performance”) - Nominal (Qualitative) Scales (incl. corresponding Dimensions/Variables): = numerical (e.g. sports player numbers, parts numbers on an assembly drawing) = textual (e.g. “hammer, pincers, screwdriver”) PROPERTY INDICARORS and their DIMENSIONS 9 INFORMATIVE A4 TS Properties - TS object/topological aspects - TS object/topological aspects
Continuous (Quantitative) Scales (incl. corresponding Dimensions/Variables): = ratio (numerical) (e.g. length, weight, duration, absolute temperature): = interval (numerical) (e.g. relative temperature, relative time): PROPERTY INDICARORS and their DIMENSIONS 10 INFORMATIVE A4 TS Properties - TS object/topological aspects - TS object/topological aspects
Ordinal (Qualitative) Scales ( incl. corresponding Dimensions/Variables): = numerical (e.g. Mohs scale of mineral hardness): = textual (or weak order) (e.g. “warm, hot,”, “grades for academic performance”): ECTS Scale Definition A Excellent – outstanding performance with only minor errors B Very good – above the average standard but with some errors C Good – generally good work with a number of notable errors D Satisfactory – fair but with significant shortcomings E Sufficient – passable performance, meeting the minimum criteria FX Fail – some more work required before the credit can be awarded F Fail – considerable further work is required PROPERTY INDICARORS and their DIMENSIONS 11 INFORMATIVE A4 TS Properties - TS object/topological aspects - TS object/topological aspects
Nominal (Qualitative) Scales ( incl. corresponding Dimensions/Variables): = numerical (e.g. sports player numbers, parts numbers on an assembly drawing): = textual (e.g. “hammer, pincers, screwdriver”): 12 Properties of Tech. Products/Systems (TS) TS PROPERTY INDICATORS and their DIMENSIONS
Measurement of TS Property Indicators However a problem arises how to generally name concrete ‘magnitudes’ of dimensions/variables corresponding to the shown miscellaneous types of scales. Except for the simplification of statements related to all the mentioned types of TS Property Indicators, the reason is that it is often impossible to predict/specify the concrete type of scale for many Dimensions/Variables (see below). Concrete ‘magnitudes’ of Dimensions/Variables corresponding to ‘Quantitative scales’ and maybe of the ‘Qualitative ordinal numerical scales’ can be called ‘parameters’ as usual. However, it is not suitable at all to call ‘parameters’ the ‘magnitudes’ of the dimensions/variables corresponding to the remaining types of the not numerical scales. Use of the (above mentioned) English term in the form “Dimension/Manifestation” or of the German term‚ “Dimension/Ausprägung” could solve this terminological obstacle. However, these terms have not any suitable equivalent in Czech, and their use without translation is not suitable as mentioned above.. VALUES of PROPERTY INDICARORS 13 INFORMATIVE A4 TS Properties - TS object/topological aspects - TS object/topological aspects
Measurement of TS Property Indicators However, considering the fact that scales for any type of dimension/variable can be expressed by both textually (linguistically) and numerically (i.e. at least by relevant numerical codes, however very often also by physically reasoned numbers, e.g. by wave lengths of light for colours) or maybe graphically, it is possible to generalise the term ‘Value’ for all types of the ‘magnitudes’ of dimensions/variables (similarly, e.g. the term “dimension” is frequently generally used both for numerical and non-numerical variables in real life and even in maths)Thus any Dimension/Variable of any TS ‘Property Indicator’ can be specified, measured, compared and evaluated by corresponding (either quantitative or qualitative) values using the established (intiutive or normative) scales. Consequently a Value of a TS Property Indicator state can be specified/measured (directly or indirectly using other TS property Indicators) by comparison using an appropriate scale. More scales can be available for a TS property Indicator! ‘Value of a TS Property’ is specified and can be measured, compared, evaluated, etc. by the corresponding set of values of the corresponding TS ‘Property Indicators’, i.e. by values of their dimensions/variables: VALUES of PROPERTY INDICARORS 14 INFORMATIVE NEEDED IMPORTANT ADDITIONAL A4 TS Properties - TS object/topological aspects - TS object/topological aspects
Measurement of TS Property Indicators Based on the conclusion above, the generalised term Value for all types of the manifestation of dimensions/variables will be used in the following (similarly like e.g. the term “dimension” is frequently and generally used both for numerical and non-numerical variables in real life and even in math). Thus any changeable TS ‘Property Indicator Dimension’ can be specified, measured, compared and evaluated by corresponding (either quantitative or qualitative) values using the established (agreed or normative) scales or rows. Notes: - As specified above the scale/row can be either quantitative i.e. numerical with corresponding units (e.g. in case of size, weight, performance Indicators, etc.) or qualitative i.e. linguistic (e.g. in case of Indicators for color, aesthetics, greenness, etc.). - Key „property Indicators“, which are measurable numerically are called „parameters“ in technical practice. The numerical value of a “property Indicator” can be converted to the equivalent non-numerical, e.g. linguistic “value” using agreed/conventional relevant scale (e.g. low, middle, high size, speed, power). The (originally) verbal “value” can be vice versa converted to the equivalent numerical value using an agreed/ conventional numerical scale (e.g. degrees of material weldability). - Similarly as in math we do not say: „value of function sinus for argument x=30o is 1/2“, but only simply „sin30o is 1/2“ (however, “function” cannot be equal to a number!), even in design engineering we do not say „value of length is 100 mm“, but only in simply “length is 100 mm“. Similarly we do not say „value of elasticity of a rod is directly proportional to its length“, but simply „ elasticity of a rod is directly proportional to its length “ (even when it is analogical conflict as in the example with function sinus above). - Similarly we usually understand the term „Indicator“ as „an Indicator including its value“ (e.g.: engine performance 80 kW). - Logically it is necessary to distinguish the difference between property Indicator and its values (e.g. Indicators of internal properties of TS themselves are independent of the Life Cycle of TS, but their values are not!). VALUES of PROPERTY INDICARORS 15 INFORMATIVE A4 TS Properties - TS object/topological aspects - TS object/topological aspects
„State of TS Property“ is determined by states of TS Property Indicators, determined by their Values (that can/must be measured, specified, predicated, evaluated, etc.): Value of a TS Property indicator is determined/measured (directly or indirectly through other TS properties/TS Property Indicators) by its (their) comparison with (an) appropriate measure scale(s). A TS properties/TS Property Indicator can be measured by different scales Notes: - In routine practice, education, however also in professional publications the term „TS Property“ usually means the „state of TS Property“ * (eg. the statement „change of TS Property“ means in fact „change of state of (indicators of) TS Property“, which finally means „change of values of TS Property Indicators“) **. - For practical reasons, the concept property indicator is analogously used for „state (resp. value) of TS Property Indicator” * (eg. In case of the indicator the „edge length“: „the edge length is 150 mm“ is used instead of “the value of the edge length is 150 mm") **. * Even „state of manifestation of TS Property" or "state of manifestation of TS Property Indicator„ etc., are theoretically exact statements, which is however not acceptable for any use. ** Analogous simplification are however used in mathematics, eg. the expression „y = f (x)“ is usually interpreted as "y equals f (x)" instead of "y equals the value of f (x)“). Beware, however, of the necessity of differentiation, where this simplification is not possible and may cause mistakes! i Value of TS Property Indicator State of TS Property Indicator State of TS Property VALUES of PROPERTY INDICARORS 16 INFORMATIVE A4 TS Properties - TS object/topological aspects - TS object/topological aspects
States of TS Property Indicators State of Value of each “TS Property Indicator Dimension” generally changes during the TS Life Cycle. Important states/values are depicted in the following Figure: Required Nominal Value Real Value Requir. lower Limit Value Required Upper Limit Value Value/State (of a dimension) of a TS Property Indicator Requested Upper Limit Deviation Requested Lower Limit Deviation Fig.: Important States/Values of a “TS Property Indicator” Dimension - Example for Quantitative (numerical) or Qualitative Numerical Dimensions/Scales VALUES of PROPERTY INDICARORS 17 INFORMATIVE A4 TS Properties - TS object/topological aspects - TS object/topological aspects
States of TS Property Indicators Current Value i.e. State of a changeable “TS Property Indicator Dimension” is in general obviously affected/determined by the current state of a TS constructional structure under its current load (in a wider sense, i.e. not only static, kinematical, dynamic, but also thermal, climatic, etc.), and by the factors of the respective preceding TS Life Cycle Transformation Systems/Processes (TrfS/TrfP) (which have caused the previous changes of the TS constructional structure compared with its original state). It is difficult to quantify the share of these two complementary constituents on resulting values/states of TS (Reflective) Property Indicator Dimensions, however it is generally possible to prove their affects. To be able to achieve, identify, evaluate, improve etc. the required future real Value/ State of a TS Property Indicator Dimesion during engineering design processes, it is necessary to consider ideal (supposed/prescribed) nominal, lower and upper ‘construc-tional’ Values of the TS life cycle TrfS/ TrfP factors including the relevant TS load. VALUES of PROPERTY INDICARORS 18 INFORMATIVE A4 TS Properties - TS object/topological aspects - TS object/topological aspects
States of TS Property Indicator The corresponding nominal, lower and upper ‘constructional’ Values/States of any TS Property Indicator Dimension (Fig. above) can then be derived/predicted for the designed TS Constructional Structure within the ideal (supposed/prescribed) TS life cycle processes using relevant more or less accurate simple/computer aided thought/expert assessment, computational and/or experimental/testing AfX (Analyses for Property X) available methods. The future/predicted or actually achieved Value/State of a ‘TS Property Indicator’ Dimension can be called a ‘real one’ (Fig. above). When speaking only about design engineering of TS the adjective ‘constructional’ can be mostly omitted (except when it is necessary to differentiate both cases). VALUES of PROPERTY INDICARORS 19 INFORMATIVE A4 TS Properties - TS object/topological aspects - TS object/topological aspects
States of a TS Property ‘ State of a TS Property’ is specified and can be measured, compared, evaluated, etc. by the corresponding set of states of the corresponding TS ‘Property Indicators’, i.e. by values/states of their dimensions. It is usually understood that ‘TS Property’ implicitly means ‘State of a TS Property’: ‘Change of a TS property’ thus means ‘Change of a TS property state’, and thus ‘Change of values/states of the dimensions of the TS property Indicators’. Value/state of a ‘TS Property Indicator’ Dimension ‘ can be either (theoretically) constant or changeable depending on one or more so-called independent variables (e.g. on running time, position of an element, affecting load, temperature, etc.). The first “variable” corresponding to the value/state of a ‘TS Property Indicator’ Dimension are then called ‘dependent variable’. The resulting dependence Indicator/function is represented in a form of two or more dimensional/variable graphical diagram. VALUES of PROPERTY INDICARORS 20 INFORMATIVE A4 TS Properties - TS object/topological aspects - TS object/topological aspects
Summary TS Property: Qualitative Indicator to describe predicted or real suitability of TS for a respective requirement (stated, generally implied or obligatory - ISO 9000:2000) TS Property Indicator: Qualitative Indicator to describe a TS Property Value of a TS Property Indicator: Quantitative Indicator to measure a TS Property Indicators and thus a TS Property TS PROPERTIES, PROPERTY INDICATORS and their VALUES 21 NEEDED A4 TS Properties - TS object/topological aspects - TS object/topological aspects
Domain: Reflective Properties Property: safety Property Indicator: number of airbags [1] Value(s) of Property Indicators : 4 Property Indicators : braking distance (50 km/h, concrete surface, dry, …) [m] Value(s) of Property Indicators : 14.2 m Property: deformation displacements, shaft B, max. operation load Property Indicators : max. bending displacement u omax [mm] (max. operation load) Value(s) of Property Indicator : 0.01 mm Property: appearance Property Indicators : overall appearance [scale e.g.: bad; satisfactory; good; excellent] Value(s) of Property Indicators : good Property: dimensions (e.g. of a part D) Property Indicators : length of the edge b [mm] Value(s) of Property Indicators : 40.5 mm Examples: Value(s) of TS Property Indicators TS Property Indicators TS Property Structure: TS PROPERTIES, PROPERTY INDICATORS and their VALUES 22 IMPORTANT A4 TS Properties - TS object/topological aspects - TS object/topological aspects
TS Behaviour ? TS BEHAVIOUR 23 © S. Hosnedl, University of West Bohemia, Pilsen, Czech Republic A4 TS Properties - TS object/topological aspects - TS object/topological aspects
Introduction TS Behaviour is a response of a TS (Constructional Structure) on (an external or internal) stimulus. TS behaviour is thus specified by changes of values (of dimensions/ “dependent variables“) of Indicators of TS Elemental Engineering Design Properties [Hubka&Eder 1988, evoked by an affecting (external and/or internal) stimulus (i.e. excitement). TS Behaviour (response) can be classified according to the changeability of the response and duration of the observation: -“Direct” static TS ‘behaviour’ (response), like values of a TS static strengths, deformation shifts from static (constant in time) load (e.g. bending deformation shifts of a loaded beam, plastic deformation shifts caused by Brinell/Vickers/Rockwell/ hardness tests) -“Direct” dynamic (both periodical and un-periodical) TS behaviour (response), like changeable values of a TS dynamic strength, deformation shifts from dynamic (changeable in time) load (e.g. dynamic strength of a car loaded by dynamic forces, crash shifts of a car loaded by shock forces) -“(Existence) Life cycle” TS behaviour (response), like changeable values of a TS dimensions, reliability, appearance, etc. on its static and dynamic “loads” (in its wider sense) during the “existence and liquidation phases” of the TS life cycle. - “Historical (generalized) TS behaviour” (response), like changeable values of TS dimensions, reliability, appearance, etc. on all “loads” (in its wider sense) during historical development of a TS class or family in time (e.g. a historical series of SKODA cars) TS BEHAVIOUR 24 NEEDED A4 TS Properties - TS object/topological aspects - TS object/topological aspects
´Direct” static TS ‘behaviour’ (response), like values of a stress, deformation shifts, etc. from static load (constant in time). (e.g. bending deformation shifts of a loaded beam, plastic deformation shifts caused by Brinell/Vickers/Rockwell/ hardness tests): Note: - This immediate static response is not usually called TS behaviour but only a ‘TS static response‘, 25 INFORMATIVE TS BEHAVIOUR A4 TS Properties - TS object/topological aspects - TS object/topological aspects
“Direct” dynamic (both periodical and un-periodical) TS behaviour (response), like changes of values of a TS dynamic strength, deformation shifts, etc. from dynamic load (changeable in time) (e.g. dynamic stresses of a machine construction loaded by dynamic forces, crash shifts of a car construction loaded by shock forces): Note: - This immediate dynamic response is usually understood as TS behaviour in its narrower sense 26 INFORMATIVE TS BEHAVIOUR A4 TS Properties - TS object/topological aspects - TS object/topological aspects
“Historical (generalized) TS behaviour” (response), like changeable values of TS dimensions, reliability, appearance, etc. on all “loads” (in its wider sense) during historical development of a TS class or family in time (e.g. a historical series of SKODA cars) [wwwSkoda 2000]): Note: - This historical long-term generalised response (to “historical technical, social, economic, laws, etc. loads”) is not usually called TS behaviour but only historical development of a TS class/family (generalized properties/property indicators). 27 INFORMATIVE TS BEHAVIOUR A4 TS Properties - TS object/topological aspects - TS object/topological aspects
“Historical (generalized) TS behaviour” (response), like changeable values of TS dimensions, reliability, appearance, etc. on all “loads” (in its wider sense) during historical development of a TS class or family in time (e.g. a historical series of SKODA cars) [wwwSkoda 2000]): Note: - This historical long-term generalised response (to “historical technical, social, economic, laws, etc. loads”) is not usually called TS behaviour but only historical development of a TS class/family (generalized properties/property indicators). 28 INFORMATIVE TS BEHAVIOUR A4 TS Properties - TS object/topological aspects - TS object/topological aspects
Summary TS Behaviour (response) can be either (more or less precisely) ascertained/predicted using relevant simple or sophisticated computer “Prediction for X” PoX simulation methods or it can be experimentally measured on models of the designed TS, or on an existing TS to predict the behaviour. To summarize, we can conclude that TS behaviour also belongs under “the umbrella” of TS properties however the corresponding (immediate, short, or long-term course of) load (in its general sense) have to be simultaneously specified (by its magnitudes within the active space and time). Load magnitudes can be specified analogously as in the case of TS Properties by values of the set of the respective Load Property Indicators. TS Properties are understood in this wider sense in the following section. 29 TS BEHAVIOUR NEEDED A4 TS Properties - TS object/topological aspects - TS object/topological aspects
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