On the Implementation of a Continuous Controller Via a Discrete Valued Controller

A procedure for implementing a continuous controller, the output of which may vary within a continuous range of values, by means of a discrete controller, of which the output may only be given a discrete set of values, is presented. The theoretical development is based on the variable structure systems approach and is complemented with an analytical and experimental study of a position servomechanism with an elastic transmission. Relevant properties of the ensuing feedback system are discussed under both nominal and perturbed operating conditions. Preliminary simulation and experimental results suggest the procedure to be reliable, easy to implement and practically feasible.