Research On Digital Pipe Routing And Simulation In Complex Products

Pipes are widely used in the fields of aviation, aerospace, automotive, shipbuilding, etc.The quality of pipe system is one of the key issues in the whole complex product. Therouting layout of pipe system is the first stage of pipe manufactory, in which manyengeering constrains such as manufacturability, stability, strength and flow resistanceshould be well considered. In this paper, we focus on how to improve the efficiency andreliability of the pipe routing layout in complex products, and to provide the basic theory,methods, and digital tools. The main work of this article are summarized as follows:(1) Based on the previous work on pipe layout design, pipe optimization, knowledgebased pipe routing, assembly simulation. The framework of digital pipe routing andsimulation and its typical process are presented. The traditional pipe routing processes incomplex products development is analyzed. Correspondingly, an improved framework ispresented with its notion, intension and typical process.(2) The digital pipe modeling method is studied. After analyzing the demand andfeatures of pipe digital modeling, the model and modeling process are presented. A pathwaybased digital representive model of pipe is presented. This model is composed by four parts,which are information model, geometry model, collision model and vitural entity model.These four parts are discussed in detail separately. Besides, the foundation of a pipeaccessory libiray is also be discussed.(3) Pipe digital routing technology is studied. The main tasks on pipe routing designare analyzed and an overall process which combines interactive with computationalalgorithm is proposed. A rapidly-exploring random trees based auto piping method and asimulated annealing based pipe optimization method are introduced to improve theefficiency and quality of the pipe routing process. By using the rapid CAD modelingtechnology, a RRT algorithm is refined to suit the complex constraints of pipe routing. Thepipe frame generated by the RRT algorithm can be adjusted by an interactive approachbased on modelling matrix. With some engineering constraints introduced, a simulated annealing based pipe routing refiner is developed to improve the quality of pipe routingresult.(4) A knowledge based pipe system assessment technology is studied. The method offormal modeling of knowledge was introduced, and the key steps of the knowledgerepresent method based on first-order predicate logic is detailed discussed to successfullyrepresent the knowledge of pipe-routing. Based on that, an ASP based pipe systemassessment algorithm is introduced to assess the quality of the pipe system. The result ofthe assessment is transferred back to the pipe routing moudule to guide the revisement ofthe pipe system.(5) A new method of assembly and disassembly process simulation in pipe system isstudied. A framework for the process simulation is proposed and a hierarchal chain basedmodel is constructed to present and store the assembly process. An improvedrapidly-exploring random tree based method is introduced to plan the disassembly path ofthe pipe parts. Based on that, a hierarchical structure of the assembly is generated whichleads to the generation of the disassembly constraint relationship graph of all the assemblyparts. By analysis the generated graph, the disassembly and assembly sequence could beobtained to guide the manufactory process.(6) The prototype system is designed and developed based on the theories andtechnologies proposed, and industrial test cases are carried out. The overall objective anddeveloping environment are briefly introduced and the software system is analyzed anddesigned in functions, modules, stucture and classes. Finally, the some typical senarios aretested in the system to illustrate its capability and validate the presented theories andtechnologies.