This design reminds me of some British Comic book type sci-fi, like from the title "2000 AD"

Have you ever seen a low budget post apocalyptic movie called "Hardware" ?

By looking at the design of this robot, I would say he's either a mechanical/repair type droid, or a combat droid. I would be tempted to go all combat mode with him, and add a lot of personalized markings such as troopers might paint onto their tank, or helicopter, or gun.... Kind of like what the space marines did in the movie "Aliens". If you have ever watched the special features, you can see how the actors were allowed to personalize their armor, and weapons.