Title
Expressing an Observer in Preferred Coordinates by Transforming an Injective Immersion into a Surjective Diffeomorphism.
Abstract
When designing observers for nonlinear systems, the dynamics of the given system and of the designed observer are usually not expressed in the same coordinates or even have states evolving in different spaces. In general, the function, denoted tau (or its inverse, denoted tau*) giving one state in terms of the other is not explicitly known and this creates implementation issues. We propose to get around this problem by expressing the observer dynamics in the the same coordinates as the given system. But this may force us to add extra coordinates, a problem that we call augmentation. This may also force us to modify the domain or the range of the "augmented" tau or tau*, a problem that we call extension. We show that the augmentation problem can be solved partly by a continuous completion of a free family of vectors and that the extension problem can be solved by a function extension making the image of the extended function the whole space. We also show how augmentation and extension can be done without modifying the observer dynamics and, therefore, with maintaining convergence. Several examples illustrate our results.
Year
DOI
Venue
2018
10.1137/15M1037755
SIAM JOURNAL ON CONTROL AND OPTIMIZATION
Keywords
Field
DocType
observer,diffeomorphism extension,immersion augmentation
Inverse,Nonlinear system,Injective function,Mathematical analysis,Pure mathematics,Observer (quantum physics),Surjective function,Mathematics,Diffeomorphism
Journal
Volume
Issue
ISSN
56
3
0363-0129
Citations 
PageRank 
References 
3
0.39
3
Authors
3
Name
Order
Citations
PageRank
Pauline Bernard1233.96
Vincent Andrieu232832.83
Praly, L.31835364.39