Research On Automatic Assembly Technology For External Pipe Of Aeroengine

As the heart of an aircraft,aeroengine is the core component of an aircraft,providing the necessary power for the aircraft.Engine development is also the most important part of the whole aircraft development process.In the 1950s,Chinese aeroengine industry started from scratch,and the research and development of aeroengine started from imitation learning,then gradually realized the process of independent research and development.Although the process is arduous,we have achieved the independent research and development of aeroengine.At present,with the improvement of digitalization level,many Aeroengine Research and development processes can be realized on the basis of digital prototype.Although the design tools and processing tools used in the external pipeline digital model of aeroengine have been informationized and automated,the construction of the external pipeline digital model and the installation of the support still remain in the pure manual stage.After the layout of the external accessories of the digital prototype is completed,the design of the external pipeline connecting the accessories mainly relies on the experience of the designers.The designers need to spend a lot of energy and time to complete the planning of the pipeline space path,the distribution of the relative position of the pipeline,the layout of the pipeline supporting parts,the modification of the pipeline interference and the inter-pipeline.Gap detection and so on.Because the assembly and laying of engine exterior pipeline consumes a lot of time and energy of designers,prolongs the whole cycle of engine research and development,and increases the cost of research and development.In order to meet the requirement of improving the overall development level of the engine,it is urgent to establish an automatic assembly and laying system for pipelines based on digital prototype and automation and intellectualization.This topic is based on UG,using C#language,the UG is redeveloped to realize the automatic assembly and laying of engine exterior pipelines.The following are the main research contents of this topic:(1)Automatic assembly.Based on the method of recognizing self-defined assembly features,automatic assembly is carried out by creating datum points and datum axes as assembly datum.It realizes the automatic assembly of mounting seat(including circular mounting seat and L-type mounting seat),clamp and bolt on different casing and mounting edge.(2)Location optimization of clamp.The genetic algorithm is used to optimize the clamp position in the pipeline.In the optimization process,the vibration frequency and amplitude of the pipeline are taken as the optimization objectives,the distance between the clamp and the pipeline end is coded,the fitness value is obtained by modal analysis of the pipeline using UG NX,and the optimal clamp position corresponding to the final optimal fitness value is obtained by crossover and mutation.(3)Pipe laying.By identifying the attachment ports,corresponding clamp ports and clamp ports with connection relationship,the automatic laying of pipelines can be realized.(4)Pipeline interference detection and interference modification.The static gap analysis method is proposed to realize static interference detection of pipeline based on UG interference core.The interferometric distance and direction of the interferometric pipeline are calculated by using the spatial mathematical model of the interferometric pipeline.The interferometric modification of the interferometric pipeline is carried out by combining the method of changing the length of the pipeline.(5)Based on above research,a prototype system for automatic assembly of aeroengine exterior pipeline is developed.