Unknown input observer design for linear time‐invariant systems—A unifying framework

This article presents a new observer design approach for linear time invariant multivariable systems subject to unknown inputs. The design is based on a transformation to the so‐called special coordinate basis (SCB). This form reveals important system properties like invertability or the finite and...

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Published inInternational journal of robust and nonlinear control Vol. 33; no. 15; pp. 8911 - 8934
Main Authors Tranninger, Markus, Niederwieser, Helmut, Seeber, Richard, Horn, Martin
Format Journal Article
LanguageEnglish
Published Bognor Regis Wiley Subscription Services, Inc 01.10.2023
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Online AccessGet full text
ISSN1049-8923
1099-1239
1099-1239
DOI10.1002/rnc.6399

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Abstract This article presents a new observer design approach for linear time invariant multivariable systems subject to unknown inputs. The design is based on a transformation to the so‐called special coordinate basis (SCB). This form reveals important system properties like invertability or the finite and infinite zero structure. Depending on the system's strong observability properties, the SCB allows for a straightforward unknown input observer design utilizing linear or nonlinear observers design techniques. The chosen observer design technique does not only depend on the system properties, but also on the desired convergence behavior of the observer. Hence, the proposed design procedure can be seen as a unifying framework for unknown input observer design.
AbstractList This article presents a new observer design approach for linear time invariant multivariable systems subject to unknown inputs. The design is based on a transformation to the so‐called special coordinate basis (SCB). This form reveals important system properties like invertability or the finite and infinite zero structure. Depending on the system's strong observability properties, the SCB allows for a straightforward unknown input observer design utilizing linear or nonlinear observers design techniques. The chosen observer design technique does not only depend on the system properties, but also on the desired convergence behavior of the observer. Hence, the proposed design procedure can be seen as a unifying framework for unknown input observer design.
Author Tranninger, Markus
Seeber, Richard
Horn, Martin
Niederwieser, Helmut
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  givenname: Martin
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  surname: Horn
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