Comments on: “When retarded nonlinear time-delay systems admit an input-output representation of neutral type”. (English) Zbl 1507.93106
Summary: It is shown that the claim \(( i )\) of Theorem 13 in the commented article is actually not true, i.e., there does not always exist a \(( s + 1 )\) th order retarded type input-output equation for a nonlinear time-delay system with observability index \(s\). For some special cases the existence of a retarded type input-output equation is described.
MSC:
| 93C15 | Control/observation systems governed by ordinary differential equations |
| 93C10 | Nonlinear systems in control theory |
| 34K40 | Neutral functional-differential equations |
| 93B25 | Algebraic methods |
Keywords:
nonlinear time-delay systems; neutral systems; retarded systems; input-output representation; algebraic approachReferences:
| [1] | Califano, C.; Moog, C. H., Observability of nonlinear time-delay systems and its application to their state realization, IEEE Control Systems Letters, 4, 4, 803-808 (2020) |
| [2] | Halás, M.; Anguelova, M., When retarded nonlinear time-delay systems admit an input-output representation of neutral type, Automatica, 49, 2, 561-567 (2013) · Zbl 1259.93066 |
This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching.
