Abstract: In order to prevent a student copying three dimensional CAD homework of others’ students,
the detection methods for copying SolidWorks documents are taken for example to analyze. Firstly,
all the possible copy methods of SolidWorks Documents are analyzed, and they can be divided into
two types which are constant feature properties copy and inconstant feature properties copy. Then,
different detection principles are proposed to the copy methods. Finally, this paper develops a
checking system for all kinds of copy methods with C++ programming language. The system can read
feature properties of SolidWorks documents, and compare their similarities to find the possible copies
for teachers. The practical application proved that the system can prevent students from copying
others’ documents efficiently.

Key words: plagiarism detection, three dimensional CAD files, SolidWorks