Summary of the invention
Technical matters to be solved by this invention is to provide a kind of device and method of the feature machining Process Knowledge Representation reasoning based on body, can solve the problem of difficult, the maintainable difference of feature machining Process Knowledge Representation and reasoning of process-type.
The technical scheme that the present invention solves the problems of the technologies described above is as follows: a kind of device of the feature machining Process Knowledge Representation reasoning based on body, comprise the domain body module, graphic parameter metallization processes Ontology Modeling module, general ontology MBM and the reasoning module that are connected successively, be provided with data-interface between described graphic parameter metallization processes Ontology Modeling module and described general ontology MBM, between described general ontology MBM and described reasoning module, be provided with plug-in unit;
Described domain body module, it forms mechanical processing technique domain body for the process knowledge in field of machining being carried out process knowledge ontology modeling;
Described graphic parameter metallization processes Ontology Modeling module, it forms parameter characteristic processing technology body for mechanical processing technique domain body being carried out modeling, and for parameter characteristic processing technology body provide image conversion feature machining process reasoning rule, also for external process feature is converted into characteristic attribute, also for by examples translating for internal feature job operation be characteristic processing method, form surface job operation tree;
Described general ontology MBM, it is converted into general statistical process ontologies and process reasoning rule, also for characteristic attribute is converted into internal feature example for parameter characteristic processing technology body and image conversion feature machining process reasoning being advised correspondence respectively;
Described reasoning module, it is for carrying out the optimization of hierarchical structure and relation according to process reasoning rule by general statistical process ontologies, excavate the relation between potential concept, obtaining the general feature machining process knowledge ontology of complete optimization, also obtaining as internal feature job operation example for internal feature example being carried out case-based reasoning.
The invention has the beneficial effects as follows: the device of a kind of feature machining Process Knowledge Representation reasoning based on body of the present invention is in feature machining process knowledge field, utilize ontology theory to carry out the expression of feature process knowledge, the problem of difficult, the maintainable difference of feature machining Process Knowledge Representation and reasoning of process-type can be solved; Secondly profit of the present invention graphically expression process knowledge, contribute to the method that user grasps knowledge maintenance, make knowledge representation more vivid, knowledge maintenance is more convenient.
On the basis of technique scheme, the present invention can also do following improvement.
Further, described data-interface is used for carrying out Data Format Transform between graphic parameter metallization processes Ontology Modeling module and described general ontology MBM, and described plug-in unit is used for carrying out exchanges data between general ontology MBM and reasoning module.
Further, described general ontology MBM adopts Prot é g é modeling tool, and described reasoning module adopts Pellet inference machine, and described graphic parameter metallization processes Ontology Modeling module adopts OGPTool.
The beneficial effect of above-mentioned further scheme is adopted to be: the present invention selects to support that the Prot é g é instrument of the OWL second edition and SWRL is as general ontology modeling, this instrument provides user oriented Visual Ontology edit tool on the one hand, graphical body can be converted into OWL form; This instrument is as general utility tool on the other hand, can be as integrated in Pellet, FaCT++, Hermit, Racer etc. with most of inference machine.
Further, described Prot é g é modeling tool and Pellet inference machine all support second edition OWL language and SWRL language, described second edition OWL language is the language of Expressive Features processing technology ontologies, and described SWRL language is the language describing process knowledge inference rule.
Further, based on OWL feature machining process knowledge ontology be expressed as four-tuple, the form of described four-tuple is (knowledge class, knowledge instance, attribute, relation); Expression based on the process knowledge inference rule of SWRL is made up of rules simplify unit, and described regular primitive shape, as function representation, represents function name by class name or relation name, variable with question mark "? " addition of variable name represents; Expression way based on the feature machining process knowledge ontology modeling of OPGTool is bulk junction paper mulberry, example, parameter process flow diagram, constraint rule and calculation expression.
Based on the device of above-mentioned a kind of feature machining Process Knowledge Representation reasoning based on body, the present invention also provides a kind of method of the feature machining Process Knowledge Representation reasoning based on body.
Based on a method for the feature machining Process Knowledge Representation reasoning of body, comprise the following steps,
S1, expresses the process knowledge in field of machining in the device of a kind of feature machining Process Knowledge Representation reasoning based on body described above, obtains the feature machining process knowledge ontology of expressing;
S2, carries out case-based reasoning by the feature machining process knowledge ontology that external process integrate features is expressed in the device of a kind of feature machining Process Knowledge Representation reasoning based on body described above, obtains surface job operation tree.
The invention has the beneficial effects as follows: the inference method of a kind of feature machining process knowledge based on body of the present invention utilizes the feature of body, establish the incidence relation of each key element in feature process knowledge, its process safeguarded only needs to add example on request, its maintenance cost reduces greatly, and the efficiency of maintenance improves greatly.
On the basis of technique scheme, the present invention can also do following improvement.
Further, the specific implementation of step S1 comprises the following steps,
S11, using the process knowledge in mechanical processing technique field as data source, to be characterized as key concept, using ontology as theoretical foundation, carries out process knowledge ontology modeling in domain body module, forms mechanical processing technique domain body;
S12, mechanical processing technique domain body is converted into computer expression mode in OGPTool, and modeling is carried out to the mechanical processing technique domain body of computer expression mode, form parameter characteristic processing technology body, OGPTool provides image conversion feature machining process reasoning rule for parameter characteristic processing technology body simultaneously;
S13, parameter characteristic processing technology body and image conversion feature machining process reasoning rule are passed in Prot é g é modeling tool by data-interface, and in Prot é g é modeling tool, be converted into expression way and the file layout of the support of Prot é g é modeling tool, corresponding generation OWL statistical process ontologies and SWRL process reasoning rule respectively;
S14, OWL statistical process ontologies and SWRL process reasoning rule are passed in Pellet inference machine by plug-in unit, and by Pellet inference machine, OWL statistical process ontologies is carried out the optimization of hierarchical structure and relation according to SWRL process reasoning rule, excavate the relation between potential concept, obtain the OWL feature machining process knowledge ontology of complete optimization, complete the expression of process knowledge.
Further, the OWL process knowledge ontology of described complete optimization is passed in Prot é g é modeling tool by plug-in unit, is then transformed in OGPTool by data-interface and stores as process knowledge.
Further, the specific implementation of step S2 comprises the following steps,
S21, inputs to external process feature in OGPTool, and is converted into the characteristic parameter of OGPTool by OGPTool;
S22, is passed to characteristic parameter in Prot é g é modeling tool by data-interface, and is converted into internal feature example by Prot é g é modeling tool;
S23, SWRL process reasoning rule in internal feature example and Prot é g é modeling tool is combined, and be passed in Pellet inference machine by plug-in unit, and carry out case-based reasoning according to the OWL feature machining technique body of the complete optimization in Pellet inference machine, obtain internal feature job operation example;
S24, is delivered in Prot é g é modeling tool by internal feature job operation example by plug-in unit;
S25, is delivered to the internal feature job operation example in Prot é g é modeling tool in OGPTool by interface, and is converted to characteristic processing method in OGPTool;
S26, derives characteristic processing method from OGPTool, obtains surface job operation tree.
Embodiment
Be described principle of the present invention and feature below in conjunction with accompanying drawing, example, only for explaining the present invention, is not intended to limit scope of the present invention.
As shown in Figure 1, a kind of device of the feature machining Process Knowledge Representation reasoning based on body, comprise the domain body module, graphic parameter metallization processes Ontology Modeling module, general ontology MBM and the reasoning module that are connected successively, be provided with data-interface between described graphic parameter metallization processes Ontology Modeling module and described general ontology MBM, between described general ontology MBM and described reasoning module, be provided with plug-in unit;
Described domain body module, it forms mechanical processing technique domain body for the process knowledge in field of machining being carried out process knowledge ontology modeling;
Described graphic parameter metallization processes Ontology Modeling module, it forms parameter characteristic processing technology body for mechanical processing technique domain body being carried out modeling, and for parameter characteristic processing technology body provide image conversion feature machining process reasoning rule, also for external process feature is converted into characteristic attribute, also for by examples translating for internal feature job operation be characteristic processing method, form surface job operation tree;
Described general ontology MBM, it is converted into general statistical process ontologies and process reasoning rule, also for characteristic attribute is converted into internal feature example for parameter characteristic processing technology body and image conversion feature machining process reasoning being advised correspondence respectively;
Described reasoning module, it is for carrying out the optimization of hierarchical structure and relation according to process reasoning rule by general statistical process ontologies, excavate the relation between potential concept, obtaining the general feature machining process knowledge ontology of complete optimization, also obtaining as internal feature job operation example for internal feature example being carried out case-based reasoning.
Fig. 2 is the system construction block diagram of the device of a kind of feature machining Process Knowledge Representation reasoning based on body of the present invention.As shown in Figure 2, described general ontology MBM is Prot é g é modeling tool, and described reasoning module is Pellet inference machine, and described graphic parameter metallization processes Ontology Modeling module is OGPTool; Described Prot é g é modeling tool and Pellet inference machine all support second edition OWL language and SWRL language, and described second edition OWL language is the language of Expressive Features processing technology ontologies, and described SWRL language is the language describing process knowledge inference rule.Domain body describes the one of disciplinary concept, comprises the constraint of relation between the concept in subject, the attribute of concept, concept and attribute and relation.Because knowledge has significant domain feature, so domain body rationally and effectively can represent knowledge." field " establishes according to the demand of ontological construction person, and it can be an ambit, can be that the one in certain several field combines, also can be in a field one among a small circle.In feature machining process knowledge ontology constructive system, domain body instrument is used for the process knowledge in mechanical processing technique field for data source, feature machining process knowledge ontology is created, concept, attribute, relation, axiom, example, the rule of morphogenesis characters processing technology ontologies according to ontology theory.In order to realize Computerized intelligent working knowledge body, suitable feature machining process knowledge ontology descriptive language is selected to support as computerese.The present invention using OWL2 (second edition of OWL) as feature machining process knowledge ontology descriptive language, using SWRL (SemanticWebRuleLanguage) as process knowledge inference rule descriptive language.OWL is as a kind of language of general process Web information content, and the reading being mainly computer applied algorithm designs, not strong for its readability of the mankind, therefore needs general ontology modeling tool support user to complete OWL Ontology Modeling.The present invention selects to support that the Prot é g é instrument of OWL2 and SWRL is as general ontology modeling, and this instrument provides user oriented Visual Ontology edit tool on the one hand, graphical body can be converted into OWL form; This instrument is as general utility tool on the other hand, can be as integrated in Pellet, FaCT++, Hermit, Racer etc. with most of inference machine.The present invention selects Pellet as rule editor and reasoning tool, realizes optimization and the case-based reasoning of body.Pellet also supports OWL2 and SWRL, and can carry out data conversion with Prot é g é by plug-in unit.Prot é g é is as the general utility tool of Ontology Modeling, and its limitation is that the process of defined notion, relation and rule is too close to language programming pattern, and technological design personnel are difficult to grasp.And process knowledge itself is empirical stronger, contain the hierarchical relationship that " agreement " is good, and inference rule branch is more, extendability requires very high, therefore needs graphic parameter metallization processes ontology modeling tool OGPTool closer to operation layer to complete the modeling of feature machining process knowledge ontology and inference rule.Bottom completes Data Format Transform between OGPTool and Prot é g é by data-interface and concept is corresponding.
Based on the device of above-mentioned a kind of feature machining Process Knowledge Representation reasoning based on body, the present invention also provides a kind of method of the feature machining Process Knowledge Representation reasoning based on body.
As shown in Figure 3, a kind of method of the feature machining Process Knowledge Representation reasoning based on body, comprises the following steps S1 and S2,
S1, expresses the process knowledge in field of machining in the device of a kind of feature machining Process Knowledge Representation reasoning based on body described above, obtains the feature machining process knowledge ontology of expressing.
The specific implementation of step S1 comprises the following steps,
S11, using the process knowledge in mechanical processing technique field as data source, to be characterized as key concept, using ontology as theoretical foundation, carries out process knowledge ontology modeling in domain body module, forms mechanical processing technique domain body;
S12, mechanical processing technique domain body is converted into computer expression mode in OGPTool, and modeling is carried out to the mechanical processing technique domain body of computer expression mode, form parameter characteristic processing technology body, OGPTool provides image conversion feature machining process reasoning rule for parameter characteristic processing technology body simultaneously;
S13, parameter characteristic processing technology body and image conversion feature machining process reasoning rule are passed in Prot é g é modeling tool by data-interface, and in Prot é g é modeling tool, be converted into expression way and the file layout of the support of Prot é g é modeling tool, corresponding generation OWL statistical process ontologies and SWRL process reasoning rule respectively;
S14, OWL statistical process ontologies and SWRL process reasoning rule are passed in Pellet inference machine by plug-in unit, and by Pellet inference machine, OWL statistical process ontologies is carried out the optimization of hierarchical structure and relation according to SWRL process reasoning rule, excavate the relation between potential concept, obtain the OWL feature machining process knowledge ontology of complete optimization, complete the expression of process knowledge.
The OWL process knowledge ontology of described complete optimization is passed in Prot é g é modeling tool by plug-in unit, is then transformed in OGPTool by data-interface and stores as process knowledge.
S2, carries out case-based reasoning by the feature machining process knowledge ontology that external process integrate features is expressed in the device of a kind of feature machining Process Knowledge Representation reasoning based on body described above, obtains surface job operation tree.
The specific implementation of step S2 comprises the following steps,
S21, inputs to external process feature in OGPTool, and is converted into the characteristic parameter of OGPTool by OGPTool;
S22, is passed to characteristic parameter in Prot é g é modeling tool by data-interface, and is converted into internal feature example by Prot é g é modeling tool;
S23, SWRL process reasoning rule in internal feature example and Prot é g é modeling tool is combined, and be passed in Pellet inference machine by plug-in unit, and carry out case-based reasoning according to the OWL feature machining technique body of the complete optimization in Pellet inference machine, obtain internal feature job operation example;
S24, is delivered in Prot é g é modeling tool by internal feature job operation example by plug-in unit;
S25, is delivered to the internal feature job operation example in Prot é g é modeling tool in OGPTool by interface, and is converted to characteristic processing method in OGPTool;
S26, derives characteristic processing method from OGPTool, obtains surface job operation tree.
In the method for a kind of feature machining Process Knowledge Representation reasoning based on body of the present invention, specifically comprise following content:
Feature machining process knowledge ontology based on OWL is expressed:
Based on OWL process knowledge ontology be expressed as four-tuple, i.e. feature machining technique body=(knowledge class, knowledge instance, attribute, relation), what embody is: OFP=(KC, KI, A, R), wherein:
1) KC (knowledge class KnowledgeClass): the set of feature machining process knowledge class (concept), as manufacture feature class (MachiningFeature) and characteristic processing method chain class (FeatureProcessChain) etc.
2) KI (knowledge instance KnowledgeIndividual): the set of feature machining process knowledge example (individuality).In processing technology, each class can have multiple knowledge individual, as
through hole be the example of feature class, the example that rough turn (RoughTurning), half finish turning (SemifinishTurning), finish turning (FinishTurning) they are car (Turning) job operation class, the example etc. that " brill-counterboring-expansion-slightly cut with scissors-finish ream " is characteristic processing method chain class.
3) A (attribute Attribute): certain characteristic being knowledge class, a certain character of reflection knowledge class.In A representation feature processing technology knowledge, the attribute of class and the set of attribute definition, be a class data attribute relation.As hole characteristic class has diameter (hasDiameter), the degree of depth (hasDepth), bottom surface cone angle (hasBottomAngle), whether has the attributes such as preformed hole (hasPreHole).
4) R (relation Relationship): the set of relation between class, individuality in representation feature processing technology knowledge is a class object relation on attributes.This type of relation is divided into two kinds, and a kind of is the hierarchical relationship Rh of representation class, has the relation Rc of technique semanteme between a kind of representation class and individuality.Hierarchical relationship Rh mainly comprises class set membership subClassOf, class brotherhood isSiblingOf, enumerates relation oneof etc. between individual and class.The relation Rc with technique semanteme refers to the process relation between class.As represented the relation hasFeatureProcessChain between manufacture feature class and characteristic processing method chain class.
Fig. 4 is the feature machining process knowledge ontology concept relation graph of the method for a kind of feature machining Process Knowledge Representation reasoning based on body of the present invention, as can be seen from Figure 4, feature machining process knowledge ontology mainly comprises five crucial classes: feature class (MachiningFeature), job operation class (MachiningProcess), characteristic processing method chain class (FeatureProcessChain), characteristic processing method class (FeatureProcess), working ability class (MachiningCapability).
1) feature class (MachiningFeature) refers to the set of manufacture feature class.Feature class as parent, using the subclass of the various characteristic types in front invention as feature class.Feature class comprises the subclass such as hole class (Hole), outside cylinder Noodles (OuterCylinder), is brotherhood between subclass.As parent, feature class gathers around characteristic public attribute, as material properties (hasMaterial), hardness (hasHardness), accuracy class (hasToleranceIT), surfaceness (hasRoughness) etc.As subclass, subcharacter class not only inherits all attributes of parent, but also allow to have the distinctive attribute of subclass self, as hole class has diameter (hasDiameter), the degree of depth (hasDepth), bottom surface cone angle (hasBottomAngle), whether has the attributes such as preformed hole (hasPreHole).
2) job operation class (MachiningProcess) refers to the set of the various job operation classes according to the definition of lathe, cutter and motion morphology, is the basis in process knowledge.Job operation class comprises the subclasses such as boring class (Drilling), boring class (Boring), turning class (Turning), milling class (Milling), is brotherhood between subclass.The subclass of job operation class enumerates class, and all examples namely by listing class are expressed or describe this type of.Job operation is enumerated all processing submethods by the difference of machining precision by the present invention, as turning class comprises the example such as rough turn (RoughTurning), half finish turning (SemifinishTurning), finish turning (FinishTurning), turning class is the combination of all these examples.
3) set of machining feature technological requirement that what characteristic processing method chain class (FeatureProcessChain) was meet, economic job operation sequential combination.Different according to feature subclass, characteristic processing method chain class comprises the subclass such as hole forming method chain (HoleProcessChain), pocket machining method chain (ProcketProcessChain), is brotherhood between subclass.According to the requirement of characteristic processing method reasoning, the attribute of defined feature Machining Methods class: the geometry state (hasPreFeature) before feature machining and physical state (hasPreCondition).
4) characteristic processing method class (FeatureProcess) is to one of the set of job operation class classification and concludes.Classified according to the feature that job operation adapts to, characteristic processing method set as the processing of applicable hole class is hole forming method class (HoleMakingProcess), comprises boring class (Drilling), reaming class (Enlarging), fraising class (Reaming), bore hole class (Boring), car hole class (Turning), hole milling class (Milling) etc.
5) working ability class (MachiningCapability) is the index set of the working ability assessment to job operation and characteristic processing method chain.Often kind of job operation (chain) all has self working ability scope (range), if the material ranges (MaterialRange) of processing, durometer level (HardnessRange), accuracy class scope (ToleranceRange), roughness range (RoughnessRange), range of size (SizeRange) and process redundancy scope (AllowanceRange) etc.
Process relation is a kind of object properties in feature machining technique body is expressed, and the characteristic that object properties have and axiom, process relation also has, as process relation has sub-attribute (hasSubProperty).Between five crucial classes of conceptual level region feature processing technology ontologies, there is following process relation: feature class and characteristic processing method chain exist relation HasFeatureProcessChain, represent that certain feature can reach technological requirement by the processing of certain characteristic processing method chain; There is relation hasMachiningCapability in job operation (chain) class and working ability class, represents the working ability scope of certain job operation (chain); There is relation hasOrderedMachiningProcess in characteristic processing method chain class and job operation class, representation feature Machining Methods is combined by some job operation; There is relation hasMachiningProcess in characteristic processing method class and job operation class, represents that some job operation is applicable to the processing of a certain category feature.
After the structure of feature machining process knowledge ontology and contextual definition are clear and definite, next need to build knowledge instance.Knowledge instance is the method entry in processing technology, have expressed characteristic processing method in detail according to class and relation.If Fig. 5 is feature machining process knowledge example sample, expression be hole category feature example and hole forming method chain example.Certain is characterized as 7 class precisions
hole hole1, surfaceness is 0.8, and material is No. 45 steel, does not have preformed hole (not cast hole) before processing.Suppose that certain characteristic processing method chain is holeprocesschain1, wherein holeprocesschain1hasFirstStepNormalDrilling, hasSecondStepCounterBoring, hasThirdStepRoughReaming, hasFourthStepFinishReaming, the method chain is adapted to have the hole machined as properties: there is no that reservation feature, material are steel, hardness is less than HB400, accuracy class be 7 grades or 8 grades, surfaceness between 0.8 ~ 1.6mm, aperture is between 20 ~ 30; The method chain has 4 steps sequentially, and bore, expand, slightly cut with scissors, finish ream, the range of work often walked is as shown in attribute in Fig. 5.Hole1 and holeprocesschain1 can be obtained by reasoning and there is hasFeatureProcessChain relation, semantically understand from technique, namely the job operation of hole1 can be holeprocesschain1, and according to the diameter value of hole1 and the working ability that often walks, can infer that the process redundancy often walked is as shown in the property value of AR1, AR2, AR3, AR4 in Fig. 5.
When expressing the relation between class, process relation is directly set up when building ontologies, but when expressing the relation between example, the relation between class can be inherited, as the relation hasOrderedMachining in Fig. 5; Part relations is then need reasoning just getable, as set up between example after hasFeatureProcessChain relation characteristics of needs process reasoning; Instance data property value under part relations is also need reasoning just can obtain, as the property value needing surplus reasoning could determine AllowanceRange example under FeatureProcessChain example hasAllowanceRange relation.
Feature process inference rule based on SWRL is expressed:
Expression based on the process knowledge inference rule of SWRL is made up of rules simplify unit, and described regular primitive shape, as function representation, represents function name by class name or relation name, variable with question mark "? " addition of variable name represents.
Feature machining process reasoning is that coupling obtains the job operation meeting feature machining and require from process knowledge.Feature machining process reasoning based on body and SWRL is the property value according to feature class example, and in the example of characteristic processing method chain class, coupling is met the example of rule.Each rule is made up of regular primitive (atom), as MachiningFeature (? f), rule primitive shape is as function representation, function name is represented by class name or relation name, variable with question mark "? " addition of variable name represents, the example of the general representation class of variable or property value.Feature machining process knowledge example sample mesopore processing instance sample according to Fig. 5, the primitive utilizing SWRL to provide expresses hole characteristic process reasoning rule.Rule description as shown in following table table 1,
Table 1
As Hole (? f) represent " if f is an example of Hole class ", this kind of expression is with the example of variable format definition class; And for example hasToleranceIT (? f,? t) accuracy class (ToleranceIT) value of expression f is t, and the attribute of example is expressed in this kind of expression with variable; For another example swrlb:greaterThanOrEuqal (? h,? hu) represent " if expression h >=hu is true ", this type of expression has used the decision logic that the Build-Ins defining variable in SWRL compares.If definition clear-cuts all before symbol "-> ", assignment are effectively and be judged to be true, then can obtain the expression formula after symbol "-> ", as hasFeatureProcessChain (? f;? c), represent to there is hasFeatureProcessChain relation between hole example f and characteristic processing method chain c.During knowledge reasoning, by above-mentioned rule judgment, if there is hasFeatureProcessChain relation between example f and example c, then the characteristic processing method chain of f is c.
Abstract concept, attribute and parameter is only comprised in the regular expression that feature process reasoning uses, the example of feature class and working ability class and attribute replace with variable, therefore, when instance properties value in feature machining process knowledge ontology changes or instance entry needs to expand, its inference rule does not need change.Regular expression is set up for feature, the job operation of often kind of feature can carry out reasoning by a rule, meet between regular example and all can set up hasFeatureProcessChain relation, therefore, multiple characteristic processing method chain can be had by reasoning feature, during actual process design, user is needed to specify or the regular Machining Methods uniquely could determining feature of newly-increased more many condition.
Feature machining technique Ontology Modeling based on OGPTool:
Expression way based on the process knowledge ontology modeling of OPGTool is bulk junction paper mulberry, example, parameter process flow diagram, constraint rule and calculation expression.
OGPTool can express statement type knowledge, control type knowledge and calculation type knowledge respectively.For providing concept and true statement type knowledge, OGPTool is described with bulk junction paper mulberry and example, as characteristic processing method chain knowledge, and the expression etc. of process redundancy; For the knowledge of control type, OGPTool parameter process flow diagram describes, as the expression of feature process inference rule; For the knowledge of calculation type, be described with constraint rule and calculation expression, as the expression that characteristic processing method chain total allowance calculates, machined parameters calculates.
Fig. 6 is that OGPTool carries out feature process ontologies modeling process, concept and the relation of knowledge had been analyzed in " the feature machining process knowledge ontology based on OWL is expressed ", ontologies is set up by same concept and relation at OGPTool, as shown in Figure 6, there is one to one " attribute " relation unlike table and tree node, and be all endowed expression formula and pa-rameter symbols for class and attribute in Fig. 6; Table 2 is certain embodiments table various types of in Fig. 6.
Table 2
Fig. 7 is the parameter process flow diagram of hole machined process reasoning rule, in order to clearly express inference rule, respectively by the pa-rameter symbols used in parameter summary sheet 1 and parameter summary sheet 2 recording parameters flow process and expression formula thereof in Fig. 7.Due in generic attribute modeling process, pa-rameter symbols was designed, then can directly reference parameter symbol and generic attribute relation in parameter Flow Chart Design process.By the judgement branch of logic control pel control law in parameter process flow diagram, the content in pel is judgment rule.
Parameter summary sheet 1
Parameter name |
Expression formula |
Pa-rameter symbols |
Hole class |
Hole |
ho |
Material |
hasMaterial |
m |
Hardness |
hasHardness |
h |
Accuracy class |
hasToleranceIT |
t |
Surfaceness |
hasRoughness |
r |
Diameter |
hasDiameter |
d |
The degree of depth |
hasDepth |
dp |
Preformed hole state |
hasPreHole |
preh |
Parameter summary sheet 2
Parameter name |
Expression formula |
Pa-rameter symbols |
Hole forming method chain class |
HoleProcessChain |
hc |
List of materials |
hasList |
ml |
The hardness upper limit |
hasUpperLimit |
hu |
Hardness lower limit |
hasLowerLimit |
hl |
The precision upper limit |
hasUpperLimit |
tu |
Precision lower limit |
hasLowerLimit |
tl |
The Ra upper limit |
hasUpperLimit |
ru |
Ra lower limit |
hasLowerLimit |
rl |
Upper dimension bound |
hasUpperLimit |
su |
Lower size limit |
hasLowerLimit |
sl |
Reservation feature state |
hasPreFeature |
pref |
Being embodied as of feature machining process knowledge ontology modeling and reasoning:
First process experiences example summarized and conclude, in OGPTool, process knowledge being expressed.The parametrization instrument of OGPTool is utilized to carry out modeling to feature machining process knowledge ontology class, class relation, generic attribute parameter list and inference rule.The explorer of OGPTool is utilized to carry out modeling to feature machining process knowledge ontology example.Then OGPTool converts feature machining process knowledge ontology expression data to XML file form, forms OWL body and expresses and SWRL rule description, be converted to class, object properties, data class attribute, individuality and inference rule respectively after Prot é g é reads.Last Pellet carries out bug check and implication relation reasoning to OWL body.
In Process Planning, first the process attribute that feature identification obtains feature is carried out to part model, then feature and attribute thereof are pushed in OGPTool with Example characteristics form, obtained the job operation of current signature by Parameter Switch and example relation inference.Finally Machining Methods is resolved to feature process, be presented in technological design platform with feature process tree construction.
The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, within the spirit and principles in the present invention all, any amendment done, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.