| A Retrospective View on Sampled-Data { Control Systems (2008) | |||||||||||||||
Abstract | |||||||||||||||
| A personal and retrospective view on sampled-data control systems is given. Emphasis is placed on the course of the discovery of a function space model, currently known as the lifted model, for this class of systems. Its impact on the frequency domain characteristics is discussed. A design example is given to illustrate the contents. 1. Prelude In this brief article, I will attempt to give a fairly personal and retrospective view on the recent developments in the theory of sampled-data control systems. The emphasis is upon how I came to discover a new function space framework, currently called lifting, for sampled-data systems, and how this notion helped to clarify certain issues in the study of such systems. It was a fairly cold day inJanuary 1971. Iwas sitting in an old classroom of Kyoto University equipped with a charcoal-type heater already obsolete even in those days, attending an introductory course on control theory for junior students. The professor was teaching us a basic treatment of sampled-data systems Figure 1. Here P (s) describes the correspondence between the incoming and outgoing signals u(s) and y(s) of the controlled plant as y(s) = P (s)u(s) in terms of Laplace transforms. Similarly, C(z) describes those of the controller via z-transform to specify its operation in discrete-time. To interface these two kinds of systems, sampling/hold operations are introduced. The former is | |||||||||||||||
Publication details | |||||||||||||||
| |||||||||||||||