Patent ID: 6236895
Filing Date: 2001-05-22
Classification: G05B

Abstract:
A discrete-time sliding mode controller for controlling the motion of a mechanical apparatus as part of a controlled system, the diserete-time sliding mode controller comprising:(a) a phase state generator for generating a discrete-time phase state signal X1.sub.k, the discrete-time phase state signal X1.sub.k comprising sample values occurring at a predetermined interval T;(b) a linear signal generator, responsive to the discrete-time phase state signal X1.sub.k, for generating a linear control signal;a sliding mode signal generator, responsive to the discrete-time phase state signal X1.sub.k, for generating a sliding mode control signal according to:.mu..DELTA.sgn(.sigma..sub.k)where .mu. is a predetermined gain, .DELTA. is a predetermined constant, .sigma..sub.k is a sliding mode variable computed from the discrete-time phase state signal X1.sub.k, and y sgn(.sigma..sub.k) returns the sign of .sigma..sub.k ;(d) a reference estimator for generating an estimated reference signal ER; and(e) a combiner for combining the linear control signal, the sliding mode control signal, and the estimated reference signal ER to generate a motion control signal U.sub.k for controlling the motion of a mechanical apparatus.