Research And Development Of3D Model Search Engine Technology Based On Model Content

In the stage of mechanical product concept design, designers often need toreference existing design models to inspire designing ideas, reuse design methods andrealize innovation design. However, the process of retrieving existing design modelsis short of convenient and effective computer tools support. Currently the widely-usedPDM system provides an available solution. It retrieves the model repository by usingthe name or number of the models. But this method is time-consuming, and usuallythe size of the searchable models is too small. So the PDM solution can’t catch therapidity, complexity and innovation requirements of modern mechanical designenvironment. In this context, with the support of the “863” National High-tech Project“Research on theory and realization of multidisciplinary collaborativemodeling/simulation supporting innovative product design”, some methods and keytechnologies on content-based3D model retrieval are studied in this paper. Then wedevelop a3d model search engine system and experimental platform named3DSearcher using these technologies. It can give great support for retrieving3Dmodels in the stage of conceptual design. The platform is very flexible, andresearchers can plug their own module into the system to test new algorithms forresearch.Key achievements of this paper are as follows:1. On the basis of experimental results, this paper made some improvement onthe “shape distribution D2” characterization and matching algorithm, and proposedthe QuickD2sampling algorithm. With QuickD2the performance bottleneck of D2algorithm was solved. As a result the efficiency of extraction the3D models featurevectors was promoted, too.2. A high performance, high expandable three-dimensional model indexalgorithm was designed in this paper, named RBK tree, based on the BK tree datastructure and metric space theory. Compared to the linear index structure, the RBKtree can efficiently prune the search space, resulting with a more efficient retrievingalgorithm. 3. Based on web crawlers and information retrieval technology, this paper didsome research on automatically3D model discovering on the internet, solved theclosed, old, lack-quantity and difficult-to-update problem of the enterprise modelrepository.4. The infrastructure of a3D model retrieval system and experiment platformwas designed and implemented in this paper. It provided flexible strategy integrationand expansion interface, as well as the basic supported tool set. Further research canbe performed base on these tools. On the basis of the infrastructure, a3D CAD modelsearch engine prototype system was developed, and finally verified using a case ofautomobile rear axle design.