Research Of Web-based Mechanical Components Intelligent Virtual Assembly

The product assembly, whose purpose is to assemble scattered parts into a complete product, is the terminal link of product manufacturing process, In the process of traditional manufacturing, two types of problems may occur, one is the product can not be assembled owing to design flaws, which often lead to product redesign. The other is, because the assembly process is unreasonable, the assembly process should be re-adjusted. These two issues will increase product cost of development, and extend the product development cycle. Virtual assembly, as one of the key technologies of Virtual Manufacturing, can be employed to solve these problems. Virtual assembly not only can verify the correctness of assembly design and operation to detect the problems in assembling process, then modify the components, but also can be used to achieve high-precision analysis, and provide more advanced assembling means for DFA(design for assembly) as well. However, the virtual assembly is a totally new technology. Both of related theory and method of virtual assembly are still not mature. Therefore, in this article, the virtual assembly theory and method involved will be discussed and analyzed in-depth, and then, based on the Java / Java 3D development platform, a Web-based intelligent virtual assembly prototype system is developed. The main contents and results show as follows:(1) Based on B/S model, a kind of virtual assembly system is built which can be applied to the basic framework, involving the data interface, user interface, virtual assembly environment and the data output of four basic modules.(2) Developed a virtual hand model with sense of immersion and interactivity, and discussed its geometric modeling and Kinematic Modeling, solving the virtual hand finger joints cracks as well. Through driving and controlling the virtual hand with a data glove, the interactive control module was developed, which can used to operate the objects by real-time simulation in virtual reality environment.(3) Proposed the concept of intelligent virtual assembly. By analysis of the relationship in the assembly process, the intelligent navigation based on the collinear constraints and coplanar constraints was studied respectively, to realize the function of intelligent assembly of mechanical parts. which can help operators to complete the assembly operations quickly and accurately.(4) Applied Virtual measurement technology into virtual assembly, and proposed the precise and fast collision detection methods, then the vernier caliper model being of a real-time and interactivity was designed.(5) Proposed the concept of parametric assembly. Based on the Study of how to extract and get the feedback of assembly components information, the parametric assembling model was developed, which can reconstruct the components corresponding to assembling orders, according to the verifying results of virtual assembly.(6) developed a prototype system of Web-based intelligent virtual assembly, and the experiments were used to examined the accuracy and feasibility of the intelligent virtual assembly theory, the results show that the prototype system can be utilized and referenced in other virtual reality application.