The spacecraft attitude tracking problem is addressed with actuator faults and uncertainties among inertias, external disturbances, and, in particular, state estimates. A continuous sliding-mode controller designed using angular velocity estimates from an arbitrary stable stand-alone observer. Rigorous analysis shows that the ensures robust stability of entire closed-loop system as long observe...

An antisaturation backstepping control scheme based on constrained command filter for hypersonic flight vehicle (HFV) is proposed with the consideration of angle attack (AOA) constraint and actuator constraints amplitude rate. Firstly, HFV system model divided into velocity subsystem height subsystem. Secondly, to handle AOA constraint, a constructed limit retain its differentiability. And rang...

A critic-only learning-based tracking control with prescribed performance was proposed for a class of uncertain nonlinear systems. Based on an estimator and optimal controller, novel controller designed to make errors uniformly ultimately bounded limited in region. First, unknown system dynamic employed online approximate the uncertainty invariant manifold. Subsequently, by running cost functio...

This paper presents an adaptive backstepping sliding mode tracking control method for underactuated unmanned surface vehicle. The controller is designed by combining and technology. virtual law used to replace the strategy of position error, transformed into velocity control, which can effectively avoid input saturation singular value problem existing in design traditional law. neural shunt mod...

This paper investigates the adaptive robust control problem based on reinforcement learning for an affine nonlinear system with unknown time-varying uncertainty. Inspired by ability to estimate uncertainty of neural network, a novel policy iteration algorithm is proposed which alternates between value evaluation, estimation, and update steps until law obtained. Especially during step approximat...

In this paper we introduce the notion of string stability of a countably infinite interconnection of a class of nonlinear systems. Intuitively, string stability implies uniform boundedness of all the states of the interconnected system for all time if the initial states of the interconnected system are uniformly bounded. It is well known that the input-output gain of all the subsystems less tha...

This paper is concerned with the exponential stability of singularly perturbed delay differential equations with a bounded (state-independent) lag. A generalized Halanay inequality is derived in Section 2, and in Section 3 a sufficient condition will be provided to ensure that any solution of the singularly perturbed delay differential equations (DDEs) with a bounded lag is exponentially stable...

Stability and Extremal Theorems for Plane Curves with Bounded Curvature Ralph Howard and Andrejs Treibergs In this note we dis uss some elementary theorems about the relation between area and length of losed embedded plane urves with bounded urvature. Our main result (see Theorem 4.1) solves the extremal problem of whi h domain has largest boundary length among embedded disks in the plane whose...

This article studies a cooperative output-feedback secure control problem for distributed cyber-physical systems over an unreliable communication interaction, which is to achieve coordination tracking in the presence of intermittent denial-of-service (DoS) attacks. Under switching network environment, first, method each subsystem proposed via neighborhood information, includes local state estim...