Those orbs are originally the "head" of the AI unit Peace Walker Basilisk which can dodge any types of missile launchers.
It should be called as Peace Walker Kimeemaru(Instead of Peace Walker Basilisk) since this wasn't called a "Metal Gear" but still it's a spiritual predecessor of latter Metal Gears as well as it's scrap parts was used for the MSF's Metal Gear Zeke. So for a more common's sake, we can still name this as KIMEE GEAR!
I knew of the Ai's of the Peace Walkers, but because of how you draw them here, It made me think of the Portal Cores AIs.
And it's hard to not say "KIMEE GEAR!" from our POV, technically it should be "PEACE WALKER!" but heh, like Shagohod, it lacks the impact of Snake shouting it and making it sound cool and funny like "METAL GEAR!".