Robot Rig (Blender 2.80)
Here is a freshly updated Robot character for you to play with.
It will work with Blender 2.80 (and above). It's a user friendly rig with a simple UI to make animation a breeze.
Although it was build to be animated in Blender, we designed it to utilize 2 rigs. One control rig, which you use to animate with, and a deformation rig which can be baked out to export into your favorite game engine.