ME506 DYNAMICS OF NONLINEAR SYSTEMS

Course Code:5690506
METU Credit (Theoretical-Laboratory hours/week):3 (3.00 - 0.00)
ECTS Credit:8.0
Department:Mechanical Engineering
Language of Instruction:English
Level of Study:Graduate
Course Coordinator:Assist.Prof.Dr HAKAN ÇALIŞKAN
Offered Semester:Fall and Spring Semesters.

Course Objectives

The objective of this course is to equip students with modern tools to analyze and predict the behavior of nonlinear dynamical systems—oscillations, limit cycles, and stability—using time-domain (Lyapunov/LaSalle), frequency-domain (describing functions; Popov, circle/parabola criteria), and perturbation/approximation methods (multiple scales, Poincaré–Lindstedt, Krylov–Bogoliubov). Emphasis is on modeling, rigorous analysis, and simulation-driven insight for engineering systems.


Course Content

Introduction to nonlinear systems. Limit cycle analysis. Piecewise linearization. Forced nonlinear systems. Approximation methods; multiple time scale, Poincare perturbation, Krylov and Bogoliubov methods. Describing function analysis. Stability of nonlinear systems; Lyapunov theory, Aizerman's and Kalman's conjectures, Lure's problem, Popov, circle and parabola criteria.


Course Learning Outcomes

By the end, students will be able to:

  • Model nonlinear systems and detect/interpret limit cycles (including via piecewise linearization).
  • Apply multiple-scale and Poincaré perturbation methods to approximate periodic solutions.
  • Use Krylov–Bogoliubov (KBM) averaging to derive amplitude/phase evolution for weakly nonlinear oscillators.
  • Compute and use describing functions to predict existence/stability of oscillations in forced nonlinear feedback.
  • Formulate Lur’e-type interconnections and assess absolute stability.
  • Apply Lyapunov’s direct method estimate regions of attraction.
  • Evaluate Aizerman’s and Kalman’s conjectures; recognize conditions and counterexamples.
  • Use Popov, circle, and parabola criteria (and related positive-real/KYP viewpoints) for frequency-domain stability certification.
  • Design and execute simulations (MATLAB) to validate analytical predictions; build Poincaré maps and phase portraits.
  • Communicate analyses clearly in technical reports with assumptions, limitations, and verification.

Program Outcomes Matrix

Contribution
#Program OutcomesNoYes
1Acquires the fundamental scientific knowledge required to analyze and solve advanced-level problems in the field of mechanical engineering.
2Gains the competence to utilize advanced engineering mathematics methods in the formulation, analysis, and solution of engineering problems.
3Conducts literature reviews using printed and online sources, analyzes the collected literature, and identifies the current state-of-the-art in the relevant scientific field.
4Demonstrates the ability to prepare and deliver a seminar on a technical subject.
5Develops the ability to conduct independent research on a specific topic and solve advanced engineering problems.
6Contributes to the national and/or international body of knowledge through original research.
7Gains the competence to effectively communicate the process and results of research conducted on a specific subject through scientifically structured written reports and oral presentations.
8Acquires the ability to publish research findings as articles in national and/or international scientific journals and/or present them as papers at conferences.
9Acts in accordance with universal principles of research and publication ethics.