Maybe part of the military Giant Voice system for public announcements.

looks like some variant of something we had in afghan. called crows or gunpacs. but the ones we had use a separate device that listened for the rapport of small arms fire. the gunner would be watching the video feed, when we got engaged by small arms the "antenna" would hone in on the area that the small arms were coming from and automatically swing the motorized turret in that direction. then the gunner would only need to move the joystick a little.

I think its a remote operated machine gun