Design and Research of a Finite Element Preprocessing System Based on AutoCAD

With the widespread application of Computer-Aided Design (CAD) technology and Finite Element Analysis (FEA) methods in engineering, efficiently and accurately completing finite element preprocessing has become a critical factor affecting simulation efficiency and result reliability. This study leverages AutoCAD as a platform and utilizes its robust secondary development capabilities to design and implement an automated finite element preprocessing system. First, we reviewed the current state of finite element preprocessing technologies and proposed an overall design framework for key modules, including geometric model extraction, simplification and cleanup, mesh generation and quality optimization, as well as boundary condition and load definition, by integrating AutoCAD's ObjectARX/.NET API and AutoLISP/VBA interfaces. Next, we detailed the system's requirements analysis, module segmentation, data flow and control flow, database and software interface design, and provided an in-depth description of algorithm optimization and implementation for geometric processing and mesh generation. Then, through typical engineering case studies, we conducted functional and performance tests on the designed system. Results showed that, compared to manual operations, the system improved model processing speed by approximately 40%, significantly enhanced mesh quality metrics (e.g., minimum angle and maximum aspect ratio), and demonstrated excellent scalability and user interactivity. Finally, we summarized the research outcomes and innovations, while also discussing the system's limitations and potential directions for future improvements. The proposed AutoCAD-based finite element preprocessing system offers efficient and reliable preprocessing support for engineering simulations, with promising prospects for broader application.