Editing Automation (section)

===Space/computer age===

With the advent of the space age in 1957, controls design, particularly in the United States, turned away from the frequency-domain techniques of classical control theory and backed into the differential equation techniques of the late 19th century, which were couched in the time domain. During the 1940s and 1950s, German mathematician [[Irmgard Flugge-Lotz]] developed the theory of discontinuous automatic control, which became widely used in [[bang-bang control|hysteresis control systems]] such as [[navigation system]]s, [[fire-control system]]s, and [[electronics]]. Through Flugge-Lotz and others, the modern era saw time-domain design for [[nonlinear systems]] (1961), [[navigation]] (1960), [[optimal control]] and [[estimation theory]] (1962), [[nonlinear control theory]] (1969), [[digital control]] and [[Filtration (mathematics)|filtering theory]] (1974), and the [[personal computer]] (1983).