CNC technology originated from the needs of the aviation industry; in the late 1940s, a U.S. helicopter manufacturer proposed the initial concept for CNC machine tools. In 1952, the Massachusetts Institute of Technology (MIT) developed a three-axis CNC milling machine. By the mid-1950s, such machines were already being used to manufacture aircraft components. During the 1960s, as CNC systems and programming methods matured and improved, CNC machine tools were adopted across various industrial sectors; however, the aerospace industry remained the largest user. Major aviation manufacturing plants were equipped with hundreds of CNC machine tools, predominantly cutting machines. Parts produced via CNC machining included integral aircraft and rocket panels, spars, skins, bulkheads, and propellers, as well as aero-engine casings, shafts, disks, mold cavities for blades, and the specialized cavity surfaces of liquid-fueled rocket engine combustion chambers. The early development of CNC machine tools focused primarily on continuous-path control systems.
Continuous-path control-also known as contouring control-requires the cutting tool to move along a specified path relative to the workpiece. Subsequently, point-to-point control CNC machine tools were vigorously developed. Point-to-point control involves moving the tool from one specific point to another; the requirement is simply to reach the target accurately, regardless of the specific path taken during the movement.
