You could install OpenSCAD on the Jobe server and write a Python-based question type that submits students code to be run by SCAD. The problem comes in grading the result, probably (as you suggest) by analysing an export file such as STL. That's a hard problem in general, though you might be able to do some useful checks using the built-in Regular Expression grader. My gut feeling is that it's not worth pursuing unless you have large classes (I'm talking hundreds of students) or if someone else has done all the hard work for you already :)
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Acest forum limitează numărul de intervenţii pe care le puteţi realiza într-un interval de timp - în prezent această limitare este de 5 intervenţii în interval de 1 zi