Knowledge Modeling And Application Of Root Crop Harvester Design

Rhizome food crops represented by potato and rhizome Chinese medicinal herbs represented by Panax notoginseng play an important role in China’s agricultural economy,but their mechanized production level does not match their industrial status.At present,the mechanized production level of rhizome crops in China is relatively low,especially in the harvest link,which is still mainly manual operation,which seriously restricts the development of related industries.In this case,in order to realize the high-quality mechanized production of rhizome crops,the first task is to adapt measures to local conditions and carry out diversified and customized designs of harvesters according to crop agronomy and user needs.However,the traditional research and development model of agricultural machinery equipment often has disadvantages such as the inability to reasonably organize and apply existing design knowledge,high development costs,low design efficiency,complicated design process,and cannot respond to user needs in a timely and effective manner.Therefore,this paper takes the root crop harvester represented by potato and Panax notoginseng as the research objects,,starts from the intelligent design requirements,collects and sorts out the multi-dimensional design knowledge required in the design process of the root crop harvester,and organizes and constructs it in a unified way based on ontology.On this basis,the knowledge base system of root crop harvesting machine was completed.It integrated and systemized the design knowledge;improved the inheritance and sharing of knowledge;finally,a function-oriented unified design system including conceptual design and detailed design is proposed,and it is integrated into the knowledge base system.Under the guidance of the system,engineers can successfully realize the reuse of design knowledge and effectively improve design efficiency.The specific research work of the thesis includes the following aspects:(1)On the basis of in-depth analysis of the design process of agricultural machinery products and a comprehensive grasp of the characteristics of agricultural machinery product design knowledge,the design knowledge of agricultural machinery products is initially divided into two categories: static and dynamic,and further subdivided into five categories according to the manifestation of knowledge: examples,experiences,parameters,rules,and processes.After completing the classification of design knowledge,through the research summary of the mainstream knowledge acquisition methods,the manual acquisition method and the semi-automatic acquisition method that combines knowledge editing and reasoning are selected to acquire the root crop harvester design knowledge from multiple knowledge sources.(2)Combined with the characteristics of common knowledge in the field of agricultural machinery design,the design knowledge of the whole machine and key components of the root crop harvester is comprehensively analyzed from the three aspects of structure,operation process and design process.The multi-dimensional design knowledge of root crop harvesting machines that has been analyzed and integrated represents the static and dynamic design knowledge of the research subject(design object and design process),and is based on the knowledge of example classes,parameter classes,rule classes,experience classes,and process classes involved in the design process of harvesting machines.With the help of function-oriented design methods,a unified modeling based on granularity has been achieved.At the same time,the design knowledge of rhizome crop harvester that has completed the structured organization is also used as a reference for concepts and relationships in the subsequent ontology construction process,and is finally stored in the directory tree of the knowledge base system.(3)Based on the research idea of semantic web,the ontology-based knowledge representation method was choosed to express the design knowledge of rhizome crop harvester;then,on the basis of referring to the composition,construction principles and construction methods of the existing ontology,combined with the characteristics of design knowledge of root crop harvesters,we proposed a method for constructing ontology of design knowledge of root crop harvesters;finally,the construction of knowledge ontology for root crop harvester design is completed with the aid of the visual ontology construction tool Protégé.After the construction of the design knowledge ontology is completed,OWL language is used to describe the ontology.After making it semantic,call the Jena package and JDBC of My Sql in the My Eclipse2010 development tool,read the OWL ontology file and successfully store it in the relational database My Sql.(4)The unified model of design knowledge ontology and related design resources of rhizome crop harvester is defined as the theoretical framework of root crop harvester knowledge base system.On this basis,the needs of users of the knowledge base system are carefully analyzed,and the planning of the knowledge base system and functional architecture for root crop harvester design is completed.After determining the system architecture,based on the Visual Studio development platform,using C# development language,Solid Works,My Sql database and Jena package and other development tools,relying on the Solid Works secondary development technology and ADO.NET data association technology to realize the development of the root crop harvester knowledge base system.(5)The key methods such as knowledge editing,knowledge query and knowledge reasoning in the process of design knowledge application are deeply studied,And these methods have been combined with the developed knowledge base system for harvesting machinery of root crops,achieving the integration of management and application of design knowledge for root crop harvesting machinery.With the help of humancomputer interaction interface and system guidance,users can successfully realize multiple functions such as design knowledge browsing and query,knowledge-based design,design knowledge ontology file download and design knowledge maintenance,which effectively improves the utilization efficiency of design knowledge.