IMPROVEMENT OF API PROGRAM TO EVALUATE THREE-DIMENSIONAL CAD MODELS

Many commercial Computer-Aided Design software have been introduced in high schools and undergraduate engineering colleges in the past decades. Basic CAD skills have become the essential engineering skill which all students need to have. Because many colleges offer basic CAD courses as early as freshman course sequences, the size of the class is quite large. That means many assignments for instructors and a lot of time to grade assignments. When instructors grade assignments, they need to open CAD files, check the accuracy of models, and close CAD files again. If they grade multiple assignments or sometime even 100s of assignments required, time to spend to grade those assignments will be tremendous. So, the CAD software API (Application Program Interface) based software was developed by author. The first version of the program was developed in 2018 and presented in the IMECE conference. The program was designed for SolidWorks using Visual Basic for Applications and provides several useful functions. The program opens multiple CAD files and check the critical values including dimensions and closes those automatically. The results are saved in Excel file to review later. The first version of the program was accepted positively by the fellow colleagues. However, there was always room for improvement. Since then, the program has been completely revamped. 1) More functions have been added to the program including the screen capture of open 3d models, 2) The program has been optimized as an independent executable program which run separately from the CAD software, 3) The program now supports multiple CAD software, 4) The program checks the watermark in the files to prevent plagiarism. In this paper, the following topics will be discussed and presented. 1) The problem with manual grading and assessment, 2) History and background of API functionality in commercial CAD software, 3) Previous development of API based evaluation software, 4) Example of the developed API program, 5) Comparison between previous program and new program. 6) Future improvement plan of API program. An actual demonstration of the program will be given during the presentation.