ABSTRACT
The concept of numerical control (NC) originated in the United States in the period 1947/48. The ability of machines to understand and process directly a numerical language, without human intervention, was made possible by the development of electronic pulse circuits and digital computers, together with servo mechanism design based on feedback principles. In 1953, a government contract was placed with the Massachusetts Institute of Technology (MIT) for a numerically controlled machine tool, and commercial versions were exhibited in Chicago during 1955. Computer numerical control (CNC) was first introduced by Alan Bradley in 1969 as reported by Barnett and Davies (1971).
