Research Information System
Thesis Type: Doctorate
Institution Of The Thesis: Gazi University, Fen Bilimleri Enstitüsü, Turkey
Approval Date: 2023
Thesis Language: Turkish
Student: Burak Eren BİRİNCİ
Principal Supervisor (For Co-Supervisor Theses): Metin Uymaz Salamci
Co-Supervisor: Bülent Özkan
Abstract:
Robustness and stability are important performance parameters for gimballed systems with electro-optical payload, such as missile seekers and aircraft, which are exposed to rapid dynamic changes and non-linear disturbance effects. Linearization of dynamic models and the classical control algorithms have been used for these systems for a long time. The variable structure controller approach is widely preferred for linear and non-linear systems among modern control methods. In this study, variable structure control methods are proposed for nonlinear systems. In this context, three new methods have been proposed with their theorems and proofs. The first of these is the state dependent derivation of the model reference sliding mode control method by combining it with the unit vector approach. The method is defined for multi-input and multi-output systems. Secondly, a sliding sector control method for single-input systems is proposed. Unlike the conventional sliding mode control, this method is based on controlling the system by directing it to a stable region around the sliding surface. In the new control algorithm proposed here, a state-dependent sector design has been created for single-input systems by including the effect of state-dependent changes in the sector and surface into the control input design. Finally, the sliding sector control, which was developed for single-input, single-output systems in the literature, has been extended to multi-input, multi-output nonlinear systems with a norm-based sector design approach. The proposed sliding sector control method is designed based on the model reference approach. In all three proposed methods, nonlinear dynamic models are solved dependent on state variables. Thus, the control algorithm has adapted to the nonlinear changes in the state variables of the dynamic system. Nonlinear dynamical models of gimbal are derived to examine the performance of the proposed methods in both simulations and real-time tests. Successful results have been obtained in real-time tests.
Key Words
: Model reference control, sliding mode control, sliding sector control,
gimbal control, nonlinear control, state dependent Riccati equations