Research On Intelligent Decision Support System For Hull Surface Forming

At present,domestic shipbuilding enterprises mainly rely on experienced workers to complete the processing and forming of hull plates.But with the rapid development of China’s shipbuilding industry and the increasing number of orders,the traditional manual processing method can not meet the increasing demand of modern shipbuilding quality and speed.Shipbuilding technology needs to be upgraded.In the "Made in China 2025" development strategy issued by the State Council,the appeal is put forward in intelligent manufacturing and green manufacturing.At present,shipbuilding enterprises are gradually using shipboard processing robots to replace the traditional manual processing.This makes the hull plate processing gradually from labor-intensive work to technical work.Therefore,it is a key link to realize the automatic processing and forming of hull plates to develop an intelligent decision support system for hull plate surface forming based on studying the forming mechanism of hull plate surface,field investigation and summarizing the processing and production experience.In order to automatically generate the hull surface forming processing scheme,this thesis mainly covers the following four aspects:(1)In this thesis,clean energy hydrogen was used as the heat source instead of oxyacetylene,and a segmented moving double ellipsoid model was adopted as the new heat source model.The forming mechanism of hull surface plate heated by a new heat source model was studied.Combined machining experiment and finite element simulation,the key to determine the segmented moving double ellipsoid heat source model model processing parameter,and using ANSYS simulation software of ship hull plate surface are established respectively thermal finite element model of temperature field,deformation field,and the different heat source model and simulation experiments of water.(2)This thesis adopts three different knowledge acquisition methods to acquire different types of knowledge,and adopts the case analysis method to acquire the knowledge of the case base;The prediction model of grey model combined with support vector machine is adopted for the knowledge of single hot-wire deformation law.Different thickness of ship plate is modeled separately,and the deformation of ship plate under different processing parameters is predicted.A large amount of deformation data of single hot-wire ship plate is accumulated to enrich the database.Rough set theory is used to acquire rule knowledge.Finally,object-oriented knowledge representation is used to express the acquired knowledge into a form that the computer can understand and process quickly.(3)On the basis of establishing the knowledge base,this thesis adopts the reasoning framework of fusion case forward reasoning and board expansion method backward reasoning.Positive reasoning is used to retrieve and calculate the similarity of relevant cases to determine the best machining scheme.Backward reasoning through plate expansion method to get the planking of the reverse of the gap,according to the position of aperture processing trajectory can be determined,the line from the aperture size can get corresponding deformation and the value of the angular distortion deformation and angular distortion values through the line again,obtained from the case matching processing parameters,the processing schemes can be used as alternative.Finally,particle swarm optimization grey Wolf algorithm was used to optimize the processing scheme based on two aspects of time and energy consumption,and the optimal processing scheme was finally obtained.(4)As for the software realization of the intelligent decision support system for hull surface forming,C# language is used to program,and Visual Studio 2017 is selected as the development platform.In this thesis,MATLAB is adopted as the algorithm realization platform,and SQL Server 2012,a relational database,is used as the background database.Finally,users can log in,upload the information of the ship plate,preview the information,generate the processing plan,modify the plan,evaluate the processing and forming,and manage the users.Finally,the processing scheme deduced by the software system is used to carry out the actual processing of the ship plate and verify the performance of the system.