This is a couple of screen grabs of the UE4 prototype for Project Mercury.  Colin Adair modeled the large Skirmisher tank (with gold trim), I made the Walker-Scout and the environment. 

Foreground tank modeled by Colin Adair.

Designed by Sven Bybee.

I had a lot of fun working on Project Mercury.  Here is a Walker-Scout model I designed, modeled and textured:

Here are some vehicle designs I made for a cancelled game I was art director on: