numerical control

computer-aided manufacturing

computer-aided manufacturing (CAM), a form of automation where computers communicate work instructions directly to the manufacturing machinery. The technology evolved from the numerically controlled machines of the 1950s, which were directed by a set of coded instructions contained in a punched paper tape. Today a single computer can control banks of robotic milling machines, lathes, welding machines, and other tools, moving the product from machine to machine as each step in the manufacturing process is completed. Such systems allow easy, fast reprogramming from the computer, permitting quick implementation of design changes. The most advanced systems, which are often integrated with computer-aided design systems, can also manage such tasks as parts ordering, scheduling, and tool replacement.

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numerical control

A category of automated machine tools, such as drills and lathes, that operate from instructions in a program. Numerical control (NC) machines are used in manufacturing tasks, such as milling, turning, punching and drilling. Both NC and CNC (computerized NC) are used to describe this category.

First-generation machines were hardwired to perform specific tasks or programmed in a very low-level machine language. Today, they are controlled by microprocessors and are programmed in high-level languages, such as APT and COMPACT II, which automatically generate the tool path (physical motions required to perform the operation).

The term was coined in the 1950s when the instructions to the tool were numeric codes. Just like the computer industry, symbolic languages were soon developed, but the original term remained.

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