[eindiran]

The 3 things mentioned so far are governed by very different regulatory regimes:

- Using a camera drone to spot game will fall under the purview of both Federal and state level Fish and Game/Wildlife departments, eg https://en.wikipedia.org/wiki/California_Department_of_Fish_... AFAIK this is not federally illegal, so there should be plenty of places where you can do this in the US.

- Drone (I assume you mean some quadcopter UAV) with a gun falls under FAA guidelines. You can't intentionally destroy them in flight or attach weapons to them for the same reason that you can't do that with planes: they are aircraft and the FAA doesn't want to deal with you shooting down aircraft. Since the FAA is federal, you can't do this anywhere in the US.

- Robot with a gun falls under ATF guidelines, specifically ATF letters that indicate certain classes of electronic trigger are effectively a machine gun and fall under the purview of the NFA. Same as point 2, the ATF rules will apply federally. If you have the relevant licensing, which I think would fall under a Class 2 SOT FFL, you can hook a firearm up to a robot since you are legally allowed by the ATF to manufacture machine guns. Most (?) of the Youtubers who have given guns to those offbrand Spots are doing it legally under the supervision of a Class 2 SOT.

- The autonomous robot with a gun would fall under the third point, as I am unaware of any rulings about specifically autonomous stuff, though someone could potentially make the argument that past rulings on booby traps could apply.

None of this directly answers the OP question about whether the 2nd amendment applies, but broadly federal regulation has moved past "shall not be infringed", so what the relevant federal agencies actually de facto allow is more to the point.