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arXiv · 2406.01251

Innovative Gain Reconfiguration for Active Fault-Tolerant Flight Control: Balance of Stability and Agility

Ege C. Altunkaya·Akin Catak·Emre Koyuncu·Ibrahim Ozkol
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Abstract

In this study, a distinct reconfigurable fault-tolerant flight control strategy is addressed for mitigating one of the persistent safety-critical issue, i.e. loss of control triggered by actuator faults. The attainable acceleration set notion is taken a step further towards incremental attainable acceleration set through a slight modification that enables instantaneous controllability checks. The inner-loop gains are updated in case of a fault using incremental attainable acceleration set and a tuning function, which is in charge as a compensator of agility and robustness. Additionally, the outer-loop gains are also such reconfigured that holding the bandwidth ratio of the successive loops at a prudent level to ensure the closed-loop stability; for this reason, an analytical outer-loop gain update law is derived based on the inner-loop gains and bandwidth, actuator and command filter time constants. Subsequently, the proposed architecture is assessed under a severe fault scenario with a demanding maneuver mission. Noticeably, the proposed method fulfills the expectations of stability and agility sufficiently, and surpasses the fixed-gain approach.

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Ege C. Altunkaya, Akin Catak, Emre Koyuncu, Ibrahim Ozkol. 2024-06-03. Innovative Gain Reconfiguration for Active Fault-Tolerant Flight Control: Balance of Stability and Agility. https://arxiv.org/abs/2406.01251

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