The effect of "Uncanny valley" (English. uncanny valley) - Hypothesis, on which the robot or other object, about looking or acting like a man (but not exactly, like a real), causes dislike and disgust at the human observers.
History
Possible causes
Psychological reason for this phenomenon is not clear still. Maybe, problem is, that man is so constituted, that at an unconscious level analyzes the slightest deviations from "normal". May be, the reason is, that at a certain level of similarity robot car with a man ceases to be perceived as a machine and starts to seem abnormal person or a lively corpse, carcasses. Moreover, cause of hostility may be symmetry Faces job, which is rarely seen in people and looks a bit intimidating.
The phenomenon of "Uncanny valley" has long been used by filmmakers, References, games and animation, to evoke a sense of fear, - Witness the Frankenstein monster, various cyborgs in human flesh, zombie, nurses from the "Silent Hill", disproportionality frightening picture of a boy on a psychedelic Bill Stounhema The Hands Resist Him or Sadako from the movie "The Ring". Artificial characters, which should arouse sympathy, should not be too similar to humans, especially if they are animated - it is well-known cartoonists.
More info on Wikipedia: link.
