Similar to Samsung’s $200,000 contraption, this home-built robotic sentry gun is “capable of picking out a human target and can accurately track/shoot him or her in the heart.” Videos after the jump.

…there are some pretty good reasons for not building an optical sentry gun, a big one being that it’s generally a good idea to shoot down any missile headed in your direction, but that same philosophy may not be the best when applied to humans

Video 1

Video 2