Animatrix Harvester 3D model *need help*

Magichobo666

hey there, im trying to create a Harvester machine of the fim called animatrix, dont ask how long it took to get there name XD.

i dont know how to start on making this thing for i dont have any of the details or concept and generally dont have a clue about going around it.

here are some pictures i was able to snapshot from the film.





this is the film clip if you want a better look, films old so bad quality
https://www.youtube.com/watch?v=cTLMjHrb_w4&feature=youtu.be&t=3m40s

do you think drawing my own concept would be advised?

Magichobo666

here some drawings i put down, has helped a bit more working out the shap of the body, not so much on detail.