AAS 97-654
CORRECTING FOR DISTURBANCES THAT A PERIODIC IN OUTPUT ANGLE RATHER THAN TIME IN REPETITIVE CONTROL SYSTEMS
W. Kang and R.W. Longman - Columbia University
Abstract
Perhaps the largest class of applications of repetitive control are to regulators that have periodic disturbances, and the repetitive controller learns what command is needed to cancel the influence of this disturbance. Very often the regulator is attempting to produce constant angular velocity of a shaft, and often the periodic disturbances are not actually periodic in time as assumed in the theory, but periodic in the output shaft angle. This paper addresses this distinction. Its effect on convergence of repetitive control algorithms is studied. Methods of accounting for the distinction are studied. Simple interpolation schemes are seen to exhibit a fading memory effect.