of Dissertation Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy NONLINEAR CONTROL FOR SYSTEMS CONTAINING INPUT UNCERTAINTY VIA A LYAPUNOV-BASED APPROACH By William MacKunis May 2009 Chair: Dr. Warren E. Dixon Major: Aerospace Engineering Controllers are often designed based on the assumption that a c...

Abstract A discrete variable structure control methodology is presented to suppress vibration of high-speed flexible parallel robot. The elastic dynamic model of the flexible robot is built by using the finite element method and experimental modal testing. Considering uncertain external disturbances and measurement noise, and uncertain parameters of the system, we can utilize invariance of the ...

In this chapter, a class of discrete time uncertain linear hybrid systems, affected by both parameter variations and exterior disturbances, is considered. The main question is whether there exists a controller such that the closed loop system exhibits desired behavior under dynamic uncertainty and exterior disturbances. The notion of attainability is introduced to refer to the specified behavio...

This paper deals with the attitude tracking control problem of rigid satellite uncertainties disturbances. An adaptive proportional derivative controller (PD) is proposed to deal influence external disturbance in controller. The uncertain disturbances can be estimated through an algorithm and compensated error closed-loop system stability are ensured based on Lyapunov analysis. using representa...

This paper addresses the adaptive asymptotic tracking control problem for nonlinear systems whose virtual gains are unknown functions of system states. Only in first step, Nussbaum gain technique is utilized to handle uncertain gain. In remaining steps, dealt with by constructing novel laws without approximation and external disturbances neural networks or fuzzy logic. New defined compensate ga...

In this paper, we propose an adaptive control approach to deal with the problems of input saturation, external disturbances, and uncertainty in unmanned autonomous helicopter system. The dynamics system take into account presence uncertainty, disturbances. Auxiliary systems are built handle saturation. neural networks applied approximate uncertain terms. scheme combining integral backstepping s...

This article considers the robust cooperative output regulation for a network of parabolic PDE systems. The solution to this problem is obtained by extending internal model principle from finite infinite dimensions. For time-invariant digraph describing communication topology, two-step backstepping approach presented systematically design state feedback regulators. allows solve both leader–foll...

Real-life planning problems are often complicated by the occurrence of disturbances, which imply that the original plan cannot be followed anymore and some recovery action must be taken to cope with the disturbance. In such a situation it is worthwhile to arm yourself against common disturbances. Well-known approaches to create plans that take possible, common disturbances into account are robu...

This paper investigates the robust ∞ H control problem for a class of uncertain switched delay systems that involve parameter uncertainties and unknown nonlinear disturbances. Based on the multiple Lyapunov functions method, a sufficient condition for the solvability of the robust ∞ H control problem is derived by employing a hysteresis switching law and variable structure controllers. When the...

In this article, one linear and one nonlinear robust control strategies are proposed for uncertain nonlinear continuous-time systems with disturbances and state delays. The approaches are based on the uncertainty and disturbance estimator (UDE) introduced in 2004. In the case of a linear controller, the terms containing the nonlinear functions and time delays are treated as additional disturban...