It may not be feasible, or even wise, to place armed security guards in every school. However, the K5 Autonomous Data Machine, pictured above, was developed after the Sandy Hook school shooting. 

While this robot may provide security, some experts also fear its monitoring capabilities will further erode personal privacy. Furthermore, "R2-D2's evil twin" may also push a lot of human security guards out of work. Knightscope, the company that develops the K5 machine, will "work" for $6.25 an hour.

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