Research On And Implementation Of CAD/CAE Integration Technologies Based On Common Geometry Interfaces

Researchers began to take interests in digital prototyping when they attempted to find the solutions to drawbacks of physical prototyping, i.e. to validate and evaluate the performance of products in the simulating way. Simulation of mechnanic performance always lies in the core of all kinds of such simulations of products. HEDP (High End Digital Prototyping), a simulation software developed by Center for Engineering and Scientific Computation, Zhejiang University, is just designed and developed to provide a solution for such goals.One of key problems of HEDP development is how to integrate it with CAD system seamlessly. Technically, there are three kinds of ways, i.e. using the neutral file standard, or using the CAD kernel, or using the outcome interfaces provided by commercial CAD systems. All the three solutions have their own advantanges and disadvantanges, and how to implement them all in one software framework is the recent research focus. Such a framework is presented in this dissertation based on the open-sourced software package, named CGM (Common Geometry Model).Chapter 1 introduces the basic design concepts and considerations, and the design of software framework for CAD/CAE integration.Chapter 2 introduces the design, functionalities and utilities of CGM in detail. CGM is an open-sourced software package under the LGPL license, which guarantees that free commercial licence could be achieved for the software integrated with CGM. CGM has a full set of geometric interfaces for CAE system development, such as the support for non-manifold geometry and virtual geometry. Moreover, its design pattern is object-oriented, which meets the need of interface extention for its functionalities if some rules are obeyed. As a bridge of CUBIT and CAD system, the effectiveness and reliability deserve our trust.Chapter 3 introduces the data transfer services based on CGM. With the IGES files as the intermedia, we implement some read/write interfaces for HEDP system to CAD systems for both 2D and 3D problems. In addition, some basic CAD data repair functionalities could be performed simultaneously with the data transfer procedure.Take a typical geometry repair algorithm as example, Chapter 4 discusses how to implement basic geometry repair algorithms based on CGM.Chapter 5, the final chapter, concludes the dissertation, and gives some suggestion for future work.