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IEEE/CAA Journal of Automatica Sinica

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L. Zhang, J. Fan, T. Chai, and F. L. Lewis, “Optimality-guaranteed model-free output feedback control using reinforcement learning,” IEEE/CAA J. Autom. Sinica, early access, 2026. doi: 10.1109/JAS.2026.126134
Citation: L. Zhang, J. Fan, T. Chai, and F. L. Lewis, “Optimality-guaranteed model-free output feedback control using reinforcement learning,” IEEE/CAA J. Autom. Sinica, early access, 2026. doi: 10.1109/JAS.2026.126134

Optimality-Guaranteed Model-Free Output Feedback Control Using Reinforcement Learning

doi: 10.1109/JAS.2026.126134
Funds:  This work was supported in part by the Research Program of the Liaoning Liaohe Laboratory (LLL23ZZ-05-01), the National Natural Science Foundation of China (61991404), the Key Research and Development Program of Liaoning Province (2023JH26/10200011), China Academy of Engineering institute of Land Cooperation Consulting Project (2023-DFZD-60-02), the National Key Research and Development Program of China (2024YFB3309701), and the Science and Technology Major Project of Liaoning Province (2024JH1/11700048)
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  • This paper investigates a data-driven, model-free optimal output feedback (OPFB) control approach for linear time-invariant (LTI) continuous-time (CT) systems. Existing data-driven OPFB control methods are hindered by the challenge that the optimality of the control policy cannot be guaranteed within the OPFB framework. To overcome this limitation, the paper introduces two novel algorithms aimed at ensuring the optimal OPFB control solution. First, by redefining the traditional performance index, an offline learning algorithm based on an augmented Hamiltonian function (AHF) is introduced. This algorithm ensures the optimality of the OPFB control solution while eliminating the need for an initial control gain. Second, to extend the algorithm’s applicability to systems with unknown dynamics, a data-driven, model-free approach leveraging off-policy integral reinforcement learning (IRL) is developed. This method operates solely on system data, demonstrating robustness against probing noise and ensuring unbiased learning outcomes. The proposed algorithms are validated through numerical simulation experiments using an F-16 aircraft system, confirming their effectiveness in practical scenarios.

     

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