Variable structure systems theory applied to sub-time optimal position control with an invariant trajectory.

A microprocessor based sliding mode controller as applied to the position control of a DC servo motor is described. In order to achieve an invariant and at the same time a fast response, the slope of the sliding line is incremented starting with a small initial value. The control law implemented has a switched current feedback term and a switched error velocity term in addition to the normal switched error term. Experimental results are presented showing the invariant nature of the system.