Discrete Dynamics in Nature and Society
Volume 2005 (2005), Issue 3, Pages 299-329
doi:10.1155/DDNS.2005.299
Abstract
This paper deals with the problem of synthesizing a
robust adaptive controller for a specific class of single-input
single-output (SISO) time-invariant hybrid controlled object
(plant) which can operate under bounded disturbances and/or
unmodeled dynamics. The hybrid plant dealt with is composed of two
coupled subsystems, one of them being of continuous-time type
while the other is digital. As a result there are also mixed
continuous-time and discrete signals present in the system
associated either with the solutions of differential equations
which depend at the same time on both discrete-time and
continuous-time forcing terms and on generalized
difference equations associated with discretized and digital
signals. The estimation algorithm is of a continuous-time nature
since the plant parameter estimates are updated for all time. It
also incorporates a relative adaptation dead-zone as a robust
stabilization mechanism which prevents against instability in the
presence of a common class of unmodeled dynamics and bounded
noise.