This is a fan art to video game called <<R type>> -->[link]
I sketch over the faint screen shot of my own 3D model to give some more detail, I created the 3D model from scratch, so its not cheating. I had this kind idea of combine the advantage of hand and computer to produce maximum result for non professional artist like me. The most difficult thing for hand sketch is that set up the correct perspective, espically complex features where nothing resemble a box can get confusing. The most difficult thing for CG is that to think about a method to create the feature I wanted, its hard to tell computer how to do the some silly shapes or details that so common to human.
I try to let the computer to do the "math", create a 3D model of the object, not too simple and not too complex. then make a screen shot and faint it in photoshop, print it out and let my hand do the "art".
the model was created in Autodesk inventor...
I did the drawing in ~1/2hour. The 3D model in ~3hour. Thinking about the concept takes way too long to count. Thought about it for days..