Page 52 - Introduction to AI Robotics

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1.6 The Seven Areas of AI
how they could be used to overcome these problems. The Handbook of Ar-
tificial Intelligence 64 divides up the field into seven main areas: knowledge
representation, understanding natural language, learning, planning and problem
solving, inference, search, and vision.

KNOWLEDGE 1. Knowledge representation. An important, but often overlooked, issue is
REPRESENTATION how does the robot represent its world, its task, and itself. Suppose a robot
is scanning a pile of rubble for a human. What kind of data structure and
algorithms would it take to represent what a human looks like? One way
is to construct a structural model: a person is composed of an oval head,
a cylindrical torso, smaller cylindrical arms with bilateral symmetry, etc.
Of course, what happens if only a portion of the human is visible?

UNDERSTANDING 2. Understanding natural language. Natural language is deceptively chal-
NATURAL LANGUAGE lenging, apart from the issue of recognizing words which is now being
done by commercial products such as Via Voice and Naturally Speaking.
It is not just a matter of looking up words, which is the subject of the
following apocryphal story about AI. The story goes that after Sputnik
went up, the US government needed to catch up with the Soviet scientists.
However, translating Russian scientific articles was time consuming and
not many US citizens could read technical reports in Russian. Therefore,
the US decided to use these newfangled computers to create translation
programs. The day came when the new program was ready for its first
test. It was given the proverb: the spirit is willing, but the flesh is weak.
The reported output: the vodka is strong, but the meat is rotten.

LEARNING 3. Learning. Imagine a robot that could be programmed by just watching a
human, or by just trying the task repeatedly itself.

PLANNING, PROBLEM 4. Planning and problem solving. Intelligence is associated with the ability
SOLVING to plan actions needed to accomplish a goal and solve problems with those
plans or when they don’t work. One of the earliest childhood fables, the
Three Pigs and the Big, Bad Wolf, involves two unintelligent pigs who
don’t plan ahead and an intelligent pig who is able to solve the problem
of why his brothers’ houses have failed, as well as plan an unpleasant
demise for the wolf.

INFERENCE 5. Inference. Inference is generating an answer when there isn’t complete
information. Consider a planetary rover looking at a dark region on the
ground. Its range finder is broken and all it has left is its camera and a
fine AI system. Assume that depth information can’t be extracted from