Depending on how innovative your engineering students are at work avoidance, the effectiveness of each of these may vary.
1)Require a log-file to be submitted along with the drawing.
2)Require a signature in each file attesting that the drawing is their own work.
3)Use proprietary tracking software to embed user and time information on each object created and to scan the submitted drawings.
4)Use a large assignment bank with random assignments such as a Moodle Quiz might allow.
5)Have them turn in a link to a YouTube video with them doing the work. They could use Screen-Cast-O-Matic with a video camera. This could double as a tool to train and correct.
6)Give each student a unique user coordinate system to start with.
7)Use employee monitoring software, such as veriato, within the legally allowable framework mutually agreed to.
.....use your imagination, possibly including subterfuge, to scare people out of cheating early.
I teach online and it has become very challenging keeping students engaged, motivated, and also to assist them on a timely basis when they run into problems, especially when those who really want to learn. AutoDesk Screencast can be used to communicate and to solve problems.
Architect, Registered NC, VA, SC, & GA.