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1、Jim Luth System Architect,Process Automation R&DOPC Foundation CTO,UA Working Group Chairman,TAC Member,TCB MemberJim.LuthSE.comTypical approach to adopting OPC UA Why the information model is an afterthoughtUse case Need to contextualize data in the cloud Any data not just automation dataOPC UA Met
2、amodel design goals Applying well understood Computer Science conceptsApplying the UA metamodel without the UA communication UA Specs are layered and decoupledUsing the UA model directly vs.translating to other technologies Ideally translations should be lossless and 2-wayConclusion2I need an automa
3、tion protocol for the factory floor34CC-LinkTCPEthernetHARTOAGISDDECOMBAPIDeviceNetProfiBusFieldBusOPC-DAHTTPWMISOAPOPC-A&EDCOM802.1x802.11IPv4UDPCANMQTTIPv6IPXOLEFTPOPC-HDAProfinetJ1939ModbusFDICANopenAS-IInterbusIndustrialEthernetControlNetDeviceLogixDHCPDNSXMLBluetoothLonworksFIPIOFirewireUSBRS-4
4、23RS-485RS-422IPsecnetDDE802.3V.35RARPARPICMPEBCDICANSIAMQP.NET RemotingSNMPUNICODEImplement OPC UA Client/Server using base information models Data Access(DA),Alarms&Conditions(A&C),Historical Access(HA)Optionally choose one or more industry specialized information models.5I need an automation prot
5、ocol for the factory floorIO LevelConsortiaEngineeringEnergyProcess AutomationFactory AutomationIndustriesITThe Industrial Interoperability StandardI need an automation protocol for the factory floorImplement a Client/Server using existing base information models Data Access(DA),Alarms&Conditions(A&
6、C),Historical Access(HA)Optionally choose one or more industry specialized information models.7Maybe add a few extra vendor Properties to some Objects and Variables.Im done ship the product!8Structure and unstructured data stored“at rest”in the cloud.Needs contextualization to be useful to AI.Can OP
7、C UA be useful to add context?Allow any real-world system to be modelled in a natural way,without compromises or limitations.Allow a standard model to be extended(by vendors)in a way that does not break the conformity to the standard model.Allow vendor extensions to be discoverable and interpretable
8、 by Clients without a priori knowledge of the extension.910 OPC UA Object Variables _ _ _ Methods _()_()_()Events AbstractionEncapsulationInheritancePolymorphismLater addition to UA InterfacesRecords connected to other records via LinksOne-to-one,one-to-many and many-to-many Links are supportedA chi
9、ld(Member)record may have more than one parent(Owner)Conceived in the 1960s as an improvement to hierarchical databasesReincarnated in current times asGraph Model Database.11Records Nodes in the UA AddressSpaceLinks UA References References are typed(and subtyped)using OOP A Reference is either symm
10、etric or asymmetric A Reference is either hierarchical or non-hierarchical1213Other relation-ship such as“contained”,“operated by”,“controls”,etc.Subclassing(Inheritance)Data Type ReferenceInstantiation(between layers)Standard and System-defined Data Type DefinitionsTop LayerType LayerRelationship B
11、ase TypesInstance LayerTopComplex Data SchemaNotation used in Presentation becomes formal OPC UA NotationDefined in Appendix of Part 5Part 8,Part 9 and Part 10 use this NotationObjectVariableObjectTypeVariableTypeMethodDataTypeViewReferenceTypeReferenceNameReferenceNameSymmetric ReferenceAsymmetric
12、ReferenceHierarchical ReferenceHasEventSourceHasComponentHasPropertyHasTypeDefinitionHasSubtypeOPC Specifications are layeredParts 3,4 and 5 are“abstract”Lacking any connection to underlying technology e.g.protocols,encodings,storagePart 6 contains the mappings to protocols and encodingsMetamodel de
13、fined in Part 3 can be used with any technology you desire not just what is described in Part 6!15Semantic Web Technologies Resource Description Framework(RDF)Web Ontology Language(OWL)16UA metamodel features are not identical to OWL/RDFEach model can represent the other with some“glue”but you dont
14、get one from the other for freeUA Semantic Validation sub-group has worked on a mapping of UA to OWL17The OPC UA metamodel can be used to create information models that never use OPC UA protocols to move data.Other ontology languages can be used instead of OPC UA With careful adaption,UA-based information models can be rendered using other ontology languagesAs OPC UA technologies are used more and more in the Cloud,the OPC Foundation needs to provide standards/guidance on best practices18