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An innovative approach to designing unknown-input observers in Takagi–Sugeno systems

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Abstract

The main objective of this research is to introduce an innovative and advanced methodology for the design of unknown-input observers adapted to continuous-time Takagi–Sugeno (T–S) systems. We focus on the development of functional observers capable of handling the unknown inputs present in the state and output equations. The design and analysis of these observers are strongly based on the principles of Lyapunov–Krasovskiĭ stability theory, providing a robust and theoretically powerful background. The convergence criteria for these observers are structured according to the formulation of linear matrix inequalities, providing a strict basis for stability analysis. In order to underline the effectiveness of the proposed approach, we offer full validation through simulation results derived from two numerical examples. These examples serve as specific demonstrations of the performance of the designed observers, highlighting their effectiveness in both reduced-order and full-order scenarios. Through this detailed exploration, we aim to highlight the applicability in actual applications and the reliability of our methodology introduced in the field of unknown-input observers for T–S systems.

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Funding

No funding is applied to support this research.

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Authors and Affiliations

  1. Laboratory of Engineering, Systems and Applications, National School of Applied Sciences, Avenue My Abdallah Km 5 Route d’Imouzzer, BP 72, Fez, Morocco

    Ghali Naami, Mohamed Ouahi & Touria Karite

  2. Missouri S &T, Rolla, MO, 65409, USA

    Martin Bohner

  3. Caen Control Lab (LAC EA-7478), University of Caen Normandie, Campus 2, Building Sciences 2, Office S2-301, 14032, Caen, France

    Fouad Giri

Authors
  1. Ghali Naami
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  2. Mohamed Ouahi
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  3. Martin Bohner
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  4. Touria Karite
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  5. Fouad Giri
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Contributions

Authors contributions Conceptualization, G. Naami.; methodology, G. Naami, M. Ouahi, M. Bohner, T. Karite and F. Giri; validation, G. Naami, M. Ouahi, M. Bohner, T. Karite and F. Giri; formal analysis, G. Naami, M. Ouahi, M. Bohner, T. Karite and F. Giri; investigation, G. Naami, M. Ouahi, M. Bohner, T. Karite and F. Giri; writing-original draft preparation, G. Naami, M. Ouahi, M. Bohner, T. Karite and F. Giri; writing-review and editing, G. Naami, M. Ouahi, M. Bohner, T. Karite and F. Giri. All authors have read and agreed to this version of the manuscript.

Corresponding author

Correspondence to Touria Karite.

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The authors have no conflicts of interest to declare. All co-authors have seen and agree with the contents of the manuscript and there is no financial interest to report. We certify that the submission is original work and is not under review at any other publication.

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Naami, G., Ouahi, M., Bohner, M. et al. An innovative approach to designing unknown-input observers in Takagi–Sugeno systems. Int. J. Dynam. Control (2024). https://doi.org/10.1007/s40435-024-01413-8

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  • DOI: https://doi.org/10.1007/s40435-024-01413-8

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