The Research Of Virtual Assembly And Its Relative Technology Based On ACIS

Assembly is the important part of the product design, assembly design has direct influence on the product quality.At now time, the market competition is more violent, the tradition assembly is not suitable for the development of the enterprises,all the enterprises need a new way to adapt the market,which is short of period,low cost and can validate the rationality of the product. It's possible to come true a high efficiency and high quality assembly because of the virtual assembly.Virtual assembly is part of the virtual design, and also the modeling technology of the virtual design is one of the key technologies of the virtual assembly. They interralate each other.The virtual assembly technology, curve and surface modeling technology are discussed in the article, and the virtual assembly navigation is researched based on the virtual assembly.The present state of virtual reality is introduced, the definition of the virtual assembly and it's function are expatiated in the article.Theory basis is supplied for the executing solution of the virtual assembly based on the deep research of sorting of assembly relationship, virtual assembly modeling and collion detection etc.The ACISVR is introduced in the article, an assembly module is developed in the ACISVR.The B-rep of ACIS is discussed , especially for the top attribute.Several assembly functions such as getting geometric feature, aligning, mating and shafting are done based on the research of B-rep.And assembly navigation module is developed based on the assembly,the article brings forward a solution of the assembly navigation ,that is the position transform matrices are recorded when the models are assembled, then the matrices are applied to the corresponding models in the navigation and the models can change position automaticaly.So it can repeat the process of the assembly again and again.The theory of the collision detection is discussed,all kinds of algorithms of collision and interference detection are summarized,and the dynamic interference detection is carried out in the assembly navigation based on the technology of"bounding box"and"by step check". Curve and surface modules are developed in the ACIS. Some curve and surface concepts are introduced, and all kinds of curve and surface modelings are carried out by using skinning,lofting, covering ,interpolating etc.