eesti teaduste
akadeemia kirjastus
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Polynomial accessibility condition for the multi-input multi-output nonlinear control system; pp. 136–150

Full article in PDF format | doi: 10.3176/proc.2014.2.04

Ülle Kotta, Maris Tõnso, Yu Kawano


The paper presents a computation-oriented necessary and sufficient accessibility condition for the set of nonlinear higher-order input-output differential equations. The condition is presented in terms of the greatest common left divisor of two polynomial matrices, associated with the system of input-output equations. The basic difference from the linear case is that the elements of the polynomial matrices belong to a non-commutative polynomial ring. The condition found provides a basis for finding the accessible representation of the set of input-output equations, which is a suitable starting point for the construction of an observable and accessible state space realization. Moreover, the condition allows us to check the transfer equivalence of two nonlinear systems.


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