In this paper, we present a global adaptive output feedback control scheme for a class of uncertain nonlinear systems to which adaptive observer backstepping method may not be applicable directly. The allowed output feedback structure includes quadratic dependency of the unmeasured states and output-dependent nonlinearities appearing not only additively, but also multiplicatively. Our novel des...

In this paper, a backstepping observer and an output feedback control law are designed for the stabilization of the one-phase Stefan Problem, which stands stand as an improvement of the recent full state feedback backstepping controller proposed in our previous contribution. The onephase Stefan Problem describes time evolution of a temperature profile in a solid-liquid material and its solid-li...

A new smooth closed loop time invariant control law is proposed for the exponential stabilization of mobile robots with nonholonomic motion constraints. The control scheme relies solely on visual information and includes an observer for the system state estimation by means of the essential matrix. The problem of model degeneracies due to short baseline is solved with the definition of a virtual...

This note is devoted to stabilizing a coupled PDE–ODE system with interaction at the interface. First, a state feedback boundary controller is designed, and the system is transformed into an exponentially stable PDE–ODE cascadewith an invertible integral transformation,where PDE backstepping is employed. Moreover, the solution to the resulting closed-loop system is derived explicitly. Second, a...

Predictive control of nonlinear systems subject to output and input constraints is considered. A fuzzy model is used to predict the future behavior. Three new ideas are proposed here. First, an added constraint on the applied control action is used to ensure the decrease of a quadratic Lyapunov function, and so guarantee Lyapunov exponential stability of the closed-loop system. Second, the feas...

The problem of state-observation is addressed for nonlinear systems that can bemodeled by an ODE–PDE series association. The ODE subsystem assumes a triangular structure while the PDE element is of heat diffusion type. The aim is to accurately estimate online the state vector of the ODE subsystem and the distributed state of the PDE element. One major difficulty is that the state observation mu...

In this paper, a novel direct self-repairing controller via quantum information technique and nonlinear fault observer is designed, which addresses tracking control and convergence rate problem of a helicopter. First, a nonlinear fault observer is designed to diagnose the helicopter’s fault. Next, in order to improve the convergence rate and stabilization of the helicopter system, an exponentia...

In this paper, we present a global adaptive output feedback control scheme for a class of 3rd-order uncertain nonlinear systems to which adaptive observer backstepping method may not be applicable directly. In contrast to the existing output feedback form, the allowed extended output feedback structure includes quadratic and multiplicative dependency of unmeasured states. Our novel design techn...

Title of dissertation: A CONTINUOUS-TIME, NONLINEAR OBSERVER FOR ESTIMATING STRUCTURE FROM MOTION FROM OMNIDIRECTIONAL OPTIC FLOW Joseph K. Conroy, Doctor of Philosophy, 2010 Dissertation directed by: Professor J. Sean Humbert Department of Aerospace Engineering Various insect species utilize certain types of self-motion to perceive structure in their local environment, a process known as activ...

This paper deals with state estimation of micro tunable capacitor subjected to nonlinear electrostatic force. For this end a nonlinear observer has been designed for state estimation of the structure.  Necessary and sufficient conditions for construction of the observer are presented. Stability of the observer is checked using Lyapunov theorem. Observer design is based on converting of differen...