http://scholars.ntou.edu.tw/handle/123456789/216 2026-04-24T07:22:12Z 2026-04-24T07:22:12Z Chiu, Chih-Hui http://scholars.ntou.edu.tw/handle/123456789/26508 2026-03-12T03:37:01Z 2025-01-01T00:00:00Z

標題: Nonlinear System Control Based on an Output Recurrent TS Fuzzy Controller 作者: Chiu, Chih-Hui 摘要: The Takagi-Sugeno (TS) fuzzy control design method has been widely utilized for nonlinear system control due to its ability to approximate complex system behaviors. Traditionally, TS fuzzy controllers are designed by computing controller gains offline using the MATLAB linear matrix inequality (LMI) control toolbox, where system parameters are obtained through the linearization of each subsystem. While this simplification reduces computational complexity, it also compromises the nonlinear characteristics of the system, leading to a discrepancy between the mathematical model and the real-world implementation. Moreover, system uncertainties and time-varying dynamics introduce further challenges, as the offline-derived controller gains may become suboptimal during actual operation, limiting the controller's adaptability and robustness. To address these issues, this study proposes an output recurrent Takagi-Sugeno fuzzy controller (ORTSFC), designed to enhance system adaptability and disturbance rejection. The novelty of this research lies in the integration of a recurrent structure within the TS fuzzy framework, transforming it from a static system into a dynamic one. This approach allows the controller to adapt continuously to real-time system dynamics, enhancing responsiveness and performance without requiring complex recalculations. Consequently, the proposed ORTSFC achieves robust control with significantly reduced computational demands. In addition, system stability is rigorously ensured through Lyapunov-based analysis. Overall, the ORTSFC provides a theoretically grounded and practically efficient solution for controlling nonlinear systems, especially under uncertainty and time-varying conditions. The main contributions of this study include: 1) Development of an ORTSFC, which introduces recurrence into the TS fuzzy control framework, improving its ability to capture dynamic system behaviors and adapt to uncertainties. 2) Application of the ORTSFC to a nonlinear control problem, specifically for the omnidirectional inverted pendulum (OIP), demonstrating its superior performance in stabilizing complex systems under uncertain conditions. Extensive simulation results validate the effectiveness of the proposed ORTSFC, showing its advantages over conventional TS fuzzy controllers in terms of adaptability, robustness, and computational efficiency.

2025-01-01T00:00:00Z Chiu, Chih-Hui Lin, Chieh-Min Peng, Ya-Fu http://scholars.ntou.edu.tw/handle/123456789/26457 2026-03-12T03:36:46Z 2025-01-01T00:00:00Z

標題: Ducted Fan Type Two-Axis Control Platform Implementation 作者: Chiu, Chih-Hui; Lin, Chieh-Min; Peng, Ya-Fu 摘要: In recent years, flying platforms have experienced rapid advancements, yet achieving stable and reliable attitude control remains a core technical challenge. This study presents a real-time control framework for a ducted fan platform equipped with two-axis control capability. To address the complexities of real-world dynamic environments, an enhanced adaptive interval type-2 fuzzy logic controller (AIT2FLC), integrated with a supervisory control mechanism, is developed. The proposed system consists of three core components: (1) an adaptive interval type-2 fuzzy controller, designed to stabilize the platform from an unstable to a stable state. This controller addresses the common limitation of conventional IT2FLCs, which often lack a systematic framework for guaranteeing stability, by incorporating an adaptive mechanism supported by Lyapunov-based analysis; (2) a supervisory controller that ensures the system states remain within predefined safety constraints, providing an additional layer of robustness against large disturbances or model uncertainties; and (3) a custom-designed ducted fan experimental platform, which enables full flight attitude control in a ground-based setting while ensuring structural safety during aggressive maneuvers and real-time validation. Unlike conventional rotorcraft testbeds, the ducted fan configuration offers a compact and enclosed propulsion system, which significantly reduces the risk of hardware damage during controller development and testing. This makes it an ideal experimental platform for evaluating advanced control strategies under various operating conditions. The main contributions of this work are twofold: (1) the development of a two-axis ducted fan platform that enables safe, repeatable, and comprehensive flight attitude control testing, and (2) the formulation of a robust control framework using interval type-2 fuzzy logic. The adaptation laws of the AIT2FLC are rigorously derived via Lyapunov stability analysis, ensuring closed-loop system stability and precise trajectory tracking. The effectiveness of the proposed control approach is validated through extensive experimental evaluations, demonstrating its robustness, fast convergence, and practical applicability in aerial platform stabilization with high reliability and safety.

2025-01-01T00:00:00Z Chen, Zheng-Zhe Lin, Hsiang-Ting Chang, Chiao-Yun Adil, Muhammad Tsai, Po-Cheng Kao, Tsung Sheng Chen, Chi Lin, Shih-Yen Shih, Min-Hsiung http://scholars.ntou.edu.tw/handle/123456789/26455 2026-03-12T03:36:45Z 2025-01-01T00:00:00Z

標題: Electrically-Driven 2D Semiconductor Microcavity Laser 作者: Chen, Zheng-Zhe; Lin, Hsiang-Ting; Chang, Chiao-Yun; Adil, Muhammad; Tsai, Po-Cheng; Kao, Tsung Sheng; Chen, Chi; Lin, Shih-Yen; Shih, Min-Hsiung 摘要: 2D monolayered transition-metal dichalcogenides (TMDCs) are promising materials for realizing ultracompact, low-threshold semiconductor lasers. And the development of the electrical-driven TMDC devices is crucial for enhancing the integration potential of practical optoelectronic systems. However, at the current stage, the electrically-driven 2-D TMDC laser has never been realized. Herein, the first electrically-driven 2-D TMDC microcavity laser have been developed. In this device, an alternating current (AC) generates electroluminescence lasing in suspended monolayered WSe2 integrated on a microdisk cavity. The input-output curve, bandwidth narrowing, and second-order coherence is analyzed to confirm the lasing characteristics at room temperature. The realization of the room-temperature AC-driven 2-D TMDC laser establishes a new area of research on electrically pumped compact lasers and is likely to assist with the implementation of diverse TMDC-based practical photonic devices in the future.

2025-01-01T00:00:00Z Jwo, Dah-Jing Chang, Yi Hsu, Yun-Han Biswal, Amita http://scholars.ntou.edu.tw/handle/123456789/26452 2026-03-12T03:36:44Z 2025-01-01T00:00:00Z

標題: Student's t Kernel-Based Maximum Correntropy Criterion Extended Kalman Filter for GPS Navigation 作者: Jwo, Dah-Jing; Chang, Yi; Hsu, Yun-Han; Biswal, Amita 摘要: Global Navigation Satellite System (GNSS) receivers may produce measurement outliers in real-world applications owing to various circumstances, including poor signal quality, multipath effects, data loss, satellite signal loss, or electromagnetic interference. This can lead to a noise distribution that is non-Gaussian heavy-tailed, affecting the effectiveness of satellite navigation filters. This paper presents a robust Extended Kalman Filter (EKF) based on the Maximum Correntropy Criterion with a Student's t kernel (STMCCEKF) for GPS navigation under non-Gaussian noise. Unlike traditional EKF and Gaussian-kernel MCCEKF, the proposed method enhances robustness by leveraging the heavy-tailed Student's t kernel, which effectively suppresses outliers and dynamic observation noise. A fixed-point iterative algorithm is used for state update, and a new posterior error covariance expression is derived. The simulation results demonstrate that STMCCEKF outperforms conventional filters in positioning accuracy and robustness, particularly in environments with impulsive noise and multipath interference. The Student's t-distribution kernel efficiently mitigates heavy-tailed non-Gaussian noise, while it adaptively adjusts process and measurement noise covariances, leading to improved estimation performance. A detailed explanation of several key concepts along with practical examples are discussed to aid in understanding and applying the Global Positioning System (GPS) navigation filter. By integrating cutting-edge reinforcement learning with robust statistical approaches, this work advances adaptive signal processing and estimation, offering a significant contribution to the field.

2025-01-01T00:00:00Z