To make "imaginary" machines look believable, study real-world aeronautics, heavy machinery, and anatomy.
To make an alien machine believable, you must include recognizable elements. sketching from the imagination sci-fi pdf
Combining real-world engineering with speculative technology. To make "imaginary" machines look believable
Your imagination can only output what you have actively observed. To build a robust sci-fi visual library, study these real-world subjects: study real-world aeronautics