Nonlinear Control Systems is a comprehensive textbook written by Robert Lien Cosgriff, which focuses on the theory and applications of nonlinear control systems. The book provides a detailed understanding of the fundamental concepts and principles of nonlinear systems, including stability analysis, Lyapunov methods, and feedback control. The author also discusses the design and analysis of various nonlinear control systems, such as adaptive control, robust control, and sliding mode control.The book begins with an introduction to the basics of nonlinear systems and their mathematical models. It then covers stability analysis using Lyapunov methods and examines the stability of equilibrium points and limit cycles. The author also discusses feedback control and its applications in nonlinear systems, including the design of proportional-integral-derivative (PID) controllers.The book then delves into advanced topics such as adaptive control, which involves modifying the control parameters in real-time to adapt to changes in the system. The author also covers robust control, which involves designing controllers that can handle uncertainties and disturbances in the system. Finally, the book discusses sliding mode control, which is a nonlinear control technique that provides robustness against uncertainties and disturbances.Overall, Nonlinear Control Systems is an essential textbook for students and researchers in the field of control systems engineering. It provides a comprehensive understanding of the theory and applications of nonlinear control systems, making it a valuable resource for both academic and industrial applications.This scarce antiquarian book is a facsimile reprint of the old original and may contain some imperfections such as library marks and notations. Because we believe this work is culturally important, we have made it available as part of our commitment for protecting, preserving, and promoting the world's literature in affordable, high quality, modern editions, that are true to their original work.