I never post in the finished works section because i never really feel that anything I do is up to the caliber of artwork I see in here. But first time for everything I suppose:
Cool racoon, the colors are good. For the tank, the tracks lacks of depth, especially in the suspension area.
Overall, the drawing, colors and concept is good. As I don't know of what series of work they are related to or are they just something you just created for fun. The racoon does look cool and the tank as well.
If you wanna give some sci-fi look to it, please modify it and make it more sophisticated.