There's lots of robot research to make them more autonomous, that is
implement devices that not only classify sensory input accurately but also
get active, e.g. shoot you. Unfortunately these devices are not yet
available for a reasonable price: 200.000 US-Dollar for the latest Armed Security Guard Robot made in Korea. Maybe I just wait and see when they show up on ebay.

I especially like the SGR-A1 model made by Samsung.
It moves it's head 180° including its sensors and the weapons. It can be
armed with different kinds of machine guns, it can recognize humans,
animals or vehicles within a range of 2km at daytimes and 1k radius at night.
It can then distinguish between friend and foe and will shoot autonomously
after warning you first.
For security reasons it has a password that it will understand up to a
distance of 10 meters, given you make it so far. This is newest technology
from Korea and I am not sure if non-korean passwords will work too. They
didn't mention that detail. I also hope that the loudspeakers to blast
out the warning (a nice femail voice btw) are capable enough before these robots enter combat mode. I can imagine that when they finished equipping
the Korean border with a line of SGR-A1s that things will be quite
noisy. So a femail voice warning you first before shooting might
be missed, right? I just try to picture these things in real life.
Oh, yea these robots can be driven using a joystick and/or a touch screen.
But you don't have to. That's the whole point.
Well, it seems so as if lots of other things might not follow the same
plot as being faced with a human guard. There might be an interesting market
for silly counter actions against autonomous robots as there are no rules
like in robo-cup.
Are you interested in getting one to protect your front garden? Maybe
you'd like to
watch a movie first and then decide. The soundtrack is available separately.
And yes, some computer games need to catch up.
Some links: