Abstract:

An adaptive iterative learning control (AILC) scheme was proposed for a class of first-order nonlinear parameterized systems with unknown time-varying delays. By utilizing boundary layer function to construct generalized tracking error, the assumption of initial condition for iterative learning control (ILC) was removed. The possible singularity problem arising from boundary layer function was avoided by introducing the hyperbolic tangent function. According to the characteristic of hyperbolic tangent function, the boundedness of all signals and the convergence of tracking errors were proved in two cases by constructing Lyapuonv-Krasovskii-Like composite energy function (CEF). Finally a simulation example demonstrates the effectiveness of the control scheme.

Key words: nonlinear parameterized systems, unknown time-varying delay, generalized tracking error, adaptive iterative learning control