Random delays of control and measurement signals during transmission over wireless network seriously affect the convergence performance of iterative learning control (ILC) systems. Based on a one-step random delay model, the transition matrix of system is derived, which contains the impact factors of random delays. For different situations of random delays, variation of eigenvalues and other elements in the lower triangular of transition matrix is analyzed, which determine the convergence speed and robust convergence respectively. Analysis shows that the convergence rate is reduced, and the robust convergence is also affected. Especially, the impact of control signal delays on robust convergence is greater than that of measurement signal
delays. Simulation results are provided to demonstrate correctness of the conclusion.
HUANG Li-xun, FANG Yong
. Impact of Random Delays in Control and Measurement Signals on Iterative Learning Control Systems[J]. Journal of Applied Sciences, 2014
, 32(2)
: 156
-162
.
DOI: 10.3969/j.issn.0255-8297.2014.02.007
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