Modelled in Cinema 4D using Kitbash elements courtesy of http://www.artstation.com/artwork/kit-bash
Rendered in Octane for C4D plugin. Postwork in Photoshop.
Concept for a Sentry Drone Mech - used for long term area denial and guarding high value military assets.
This image recently won a CG Society Gold Award and Image of the Month in 3D Artist Magazine.