Page 131 - Concise Encyclopedia of Robotics

Actual range
Apparent Frame
range Barrier

Foreshortening

FORWARD CHAINING
A computer can act as a person knowledgeable in some field, such as
engineering, weather forecasting, medicine, or even the stock market.
Programs that make computers act like specialists are called expert systems.
When running an expert system, you supply the computer with infor-
mation, and the computer solves a problem based on that information.
There are two ways in which the data can be supplied when using an
expert system. You can input the facts one at a time, as the computer
requests them; or you can input all the data at once, before the program
begins working toward a solution. The latter method is forward chaining.
The chain of reasoning starts from a single set of facts, and works forward
until the problem is solved or a conclusion is reached.
After a computer receives the data in a forward-chaining expert system,
the inference engine uses rules, written in the software, to infer a solution
or conclusion. If more information is necessary, the computer will let
the operator know, usually by asking specific questions. Compare BACK-
WARD CHAINING.
See also EXPERT SYSTEM.
FRAME
A frame is a mental symbol, a means of representing a set of things. Frames
can be envisioned as “windows in the mind.”In artificial intelligence (AI),
objects and processes can be categorized in frames.
Suppose a robot is given the command, “Go to the kitchen and pour
some water into a paper cup.”The robot goes through a series of deductions

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