How about a Security Robot with Taser, Security can maintain a safe location to control the robot and in effect still protect the premises... Of course would be equipped with normal camera, sound, voice with a body possibly arms? the body would need design to avoid tipping over easy either by terrain but also any would be intruder.
I feel it would allow security officer to avoid the dangerous first encounter, that is mystery as to if intruder is aggressive or extremely dangerous .
There are times when the security camera's are not enough!
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