Unknown Input Interval Observers for Linear Positive Systems

https://doi.org/10.58571/CNCA.AMCA.2025.046

Resumen: This paper presents the design of an Unknown Input Interval Observer for positive linear systems. The proposed methodology extends conventional unknown input observer (UIO) frameworks to systems constrained within the positive quadrant of the Euclidean space, a crucial requirement in various applications where state and output variables must remain non-negative. The approach is formulated using Linear Matrix Inequalities (LMIs), allowing the derivation of conditions that ensure the existence of the observer, as well as the positivity and convergence of state estimates. Additionally, the estimation error dynamics are shown to be cooperative, thereby ensuring that the true state trajectories are bounded between robust upper and lower estimates, even in the presence of unmeasured disturbances and model uncertainty. The effectiveness of the proposed scheme is validated through a numerical case study, demonstrating its applicability in a wide variety of positive systems.

¿Cómo citar?

Avilés, J., Becerra, G., Mera, M., Morales, J., Flores, J., Márquez,C., Martínez, R. & Vazquez, J. (2025). Unknown Input Interval Observers for Linear Positive Systems. Memorias del Congreso Nacional de Control Automático 2025, pp. 268-273. https://doi.org/10.58571/CNCA.AMCA.2025.046

Palabras clave

Unknown Input Observer, Interval Observer, Positive systems.

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