Makina Mühendisliği

Bu koleksiyon için kalıcı URI

http://hdl.handle.net/11527/25302

Gözat

Yazar "Altuğ, Erdinç" ile Makina Mühendisliği'a göz atma
  • Öge
    Experimental test of fault tolerant real time operational modal analysis method by voting algorithm for aircrafts
    (ACM, 2024) Köken, Metin ; Altuğ, Erdinç ; https://orcid.org/0009-0007-9703-0722 ; https://orcid.org/0000-0002-5581-7806 ; Makina Mühendisliği
    Operational modal analysis (OMA) is a key technique to obtain real-time modal parameters (natural frequency, damping ratio, mode shapes) for aircraft. Due to the nature of an aircraft, an extended flight envelope leads to the flexible structures being highly nonlinear and time-variant. For structural health monitoring and real-time flutter test purposes, automated and robust operational modal analysis methods are required. However, each automated OMA method has its own advantages and disadvantages in specific conditions. In this paper, stochastic subspace identification (SSI), autoregressive poly reference (AR PR), Ibrahim time domain (ITD), eigensystem realization algorithm (ERA) and frequency-spatial domain decomposition method (FSDD) operational modal analysis algorithms were investigated on real-time aircraft flight data. Automated versions of these algorithms are used to obtain real-time modal parameters (natural frequency, damping ratio, and mode shapes). Furthermore, the present work focuses on the development of an enhanced method by utilizing each algorithm simultaneously. The enhanced method aims to calculate the real-time modal parameters without the requirement of users to pick physical modes by voting algorithm between the calculated parameters from each method. Each method and enhanced method were tested for flight data and results were verified by ground vibration test (GVT). It is observed that the voting algorithm improves the robustness of the real-time results in different flight conditions when disadvantageous methods in that specific condition are influenced, by compensating with advantageous methods.
  • Öge
    Precise orientation control of gimbals with parametric variations using model reference adaptive controller
    (Wiley, 2024) Çakmak, Ömer ; Altuğ, Erdinç ; orcid.org/0000-0002-5581-7806 ; Makina Mühendisliği
    This study focuses on a model reference adaptive control method that ensures identical orientation outputs for different prototypes of a two-axis gimbal produced in mass production. In this method, unlike traditional MRAC structures, an MRAC structure is used in conjunction with state feedback control. First, the reasons for the need for an adaptation mechanism in gimbals and why Model Reference Adaptive Control (MRAC) alone won't be sufficient have been discussed. In the first section, various applications of MRAC have also been mentioned. Then, the mathematical foundation of the model reference adaptive controller used in this study is elaborately explained, followed by stability analyses. In the next step, an ideal reference model exhibiting desired behavior and a real system model with different dynamics are created in a simulation environment. This allows a comparison of the adaptation capabilities of only MRAC and MRAC+State Feedback controllers. Based on the information gathered in this section, the recommended approach in the article is tested on a real gimbal system, and the results are shared. The obtained results demonstrate that the MRAC+State Feedback control structure significantly reduces the error in the gimbal's orientation response compared to the reference model.