Now lets do a robotic rhinos and elephants. Upon detection of a shot and a specific place it came from (using radar and sound sensor) the robot turns and starts to run in in that direction unleashing a salvo from a range of weapons - from non-lethal 96GHz direct energy and infra-red sound to water cannon to rubber bullets to RPG shots with sound and light grenades ... That is for the first time offenders. If face recognition detects second-time offender - lethal weapons applied, automatic rifle, RPG with real grenades, fire throwers. Also the robot can launch drones and there is a gamut of opportunities here...

>Barring a direct shot to the circuitry, the decoys can last five to 10 years.

simple [body] armor plates should do here.