Research On Key Technology Of Service-oriented Open CNC System Design

In the era of industrial 4.0,with the deep integration of the new generation of information technology,such as cloud computing and Internet of things,and the advanced manufacturing mode such as virtualization and networking,the intelligentization level of manufacturing system has been greatly improved.The requirement of CNC system with higher level of openness,flexible reconfiguration and rapid integration will lead to new changes in the architecture and design concept of itself,which comes from the rapid flow and configuration of production factors in the manufacturing system,the change of market demand and individuation and the mass customization of diversified products.In order to meet the new development needs in the manufacturing field,this paper presents a design method of open CNC system based on the idea of service-oriented,and conducts in-depth analysis and research on the key problems such as service-oriented CNC domain modeling language design,formal modeling,verification,the optimization of service composition.For the core issues in the SOA implementation process,such as the service encapsulation of numerical control function,the combination of semantic modeling and so on,this paper proposes the design framework of service-oriented open CNC system to integrate the work of modeling,validation,simulation,and implementation related to conceptual design and process design into a unified framework,which combines key technologies such as domain modeling,formal semantic description and multi-objective optimization.The proposed design framework follows the system design process of service modeling,service composition,combination validation,and combinatorial optimization,which can ensure the smooth implementation of CNC system design under service-oriented architecture.How to build service oriented application system modeling is the key link to realize service oriented design.Considering this,this paper proposes a domain modeling technology to solve the problem of application system modeling in the design process of service-oriented CNC system by deeply studying the mapping relationship between IEC 61499 reference model and SOA general architecture.The design of service-oriented domain metamodel is the key task of realizing of service-oriented modeling in CNC domain.In order to ensure the accuracy of the metamodel,a formal description method is employed to guide the design of metamodel.Based on the design strategy of multidimensional separation concerns and port interface nesting,the metamodel of the numerical control domain features,the IEC 61499 reference model,and the SOA components are designed,which compose a composite numerical control domain metamodel with the multiple information.Service composition is the key and difficulty of service integration.In the process of service composition modeling,we need to describe exactly the combination semantics of CNC services,define the execution sequence and interaction process of component services in composite services.Based on model of computation,SR MoC,DE MoC and TM MoC are selected to implement the modeling of CNC service composition semantics.For the validation of service composition model,the process specification is described based on the mixed computation tree logic and the AWBFSL algorithm and the symbol model checking tool are used to verify the service composition model.In the process of building CNC applications,a specific requirement often corresponds to a large number of candidate service composition schemes that match a large number of functions.In this case,the selection of the optimal quality combination scheme from the candidate service composition scheme equals to the search problem of design space.From the point of view of multi-objective optimization,taking the service quality of different aspects,such as processing error,processing speed and resource utilization rate as reference,a multi-objective optimization model for numerical control service composition is established in this paper.At the same time,in order to improve the efficiency of solving the optimal solution in the complex search space,the extended NSGA-II algorithm is used.Finally,To seamlessly integrate design activities such as requirements analysis,modeling,verification and deployment at different stages,This paper presents the implementation of support toolset including modeling tools,model transformation tools,and target platform adaptation tools,which is convenient for designers to quickly customize and build different types of CNC systems.Taking a PCB micro drill automatic grooving machine numerical control prototype system as an example,based on C/S architecture and multi-level function abstraction,the specific software and hardware implementation plan is given.The implementation model of the core control unit is constructed in the way of service integration and then the model detection method is used to verify the correctness of the combined service behavior and multi-objective optimization technology is used to select the combination service parameters.Taking a specific micro drill as an example,the actual processing effect of the control system is tested,and the feasibility and effectiveness of the design method is verified.