The uncertainty and disturbance estimation (UDE)-based robust control strategy is able to achieve good performance by estimating compensating the in a system with filter having appropriate frequency characteristics. However, how systematically design reference UDE-based asymptotic tracking rejection still missing literature. In this paper, solved applying well-known internal model principle. conditions guarantee closed-loop stability are derived. Experimental results on servo presented as an...

In this article, an uncertainty and disturbance estimator (UDE)-based robust output feedback control technique without using a state observer is proposed for general class of nonlinear single-input single-output systems that are bounded-input bounded-output stable subject to input disturbances. Instead designing controller the original system directly, equivalent consisting first-order linear plus lumped term used represent input-output relationship. Then, UDE-based designed only bandwidth...

In this brief, a bounded integral controller (BIC) with limited control power is proposed for class of nonlinear multiple-input multiple-output (MIMO) systems. The sum-of-squares constraint on the inputs time-varying weights studied and handled through BIC design, which guarantees that both an auxiliary variable are dynamically constrained designed circle. inherits properties traditional to eliminate tracking errors achieve disturbance rejections. Even under input weights, independently...

This paper proposes an uncertainty and disturbance estimator (UDE)-based controller for nonlinear systems with mismatched uncertainties disturbances, integrating the UDE-based control conventional backstepping scheme. The adoption of scheme helps to relax structural constraint control. Moreover, reference model design in offers a solution address “complexity explosion” problem approach. Furthermore, strict-feedback form condition approach is also relaxed by using estimate compensate...

This paper considers a novel algorithm for the routing problem of autonomous underwater vehicles (AUVs) in order to deliver customized sensor packages mission targets at scattered positions. We aim utilize set AUVs serve all exactly once on premise individual limited loading ability while guaranteeing least total energy cost presence ocean currents. The main idea is based decomposition initial into two subproblems: assignment and generation sub-path between targets. present an integrated...

Motion planning is a crucial, basic issue in robotics, which aims at driving vehicles or robots towards to given destination with various constraints, such as obstacles and limited resource. This paper presents new version of rapidly exploring random trees (RRT), that is, liveness-based RRT (Li-RRT), address autonomous underwater (AUVs) motion problem. Different from typical RRT, we define an index each node the searching tree, called “liveness” this paper, describe potential effectiveness...

In this paper, a novel robust control strategy named uncertainty and disturbance estimator (UDE) is applied to the stabilization of an unstable heat equation with Dirichlet type boundary actuator unknown time-varying input disturbance. The system stabilized by backstepping approach compensated UDE-based method which constructs estimation through filtering U(t) state u(1, t). Compared other existing compensation methods, only requires spectrum information signal. Furthermore, output feedback...

The robust tracking problem of a class linear switched systems with both model uncertainty and external disturbance is investigated. Firstly, some new stability results for the are obtained in following two cases: one under arbitrary switching paths, other paths average dwell time. Secondly, control strategy based on existing estimator (UDE)-based method developed system disturbance. asymptotic closed-loop established above mentioned paths. Finally, important features good performance...

In this paper, a robust control method based on the uncertainty and disturbance estimator (UDE) is developed to achieve attitude tracking for quadrotor. To facilitate design, coupled terms in roll, pitch yaw dynamics are lumped into term remained can be regarded as decoupled subsystems. As result, each subsystem, contains all terms, uncertainties disturbances, then UDE applied compensation. Compared with existing works, introduced filtered error simplifies controller design implementation....

This paper investigates the fault diagnosis and tolerant control problems for actuators of marine vehicles through processes detection, isolation, control. Two categories observers contribute to detect predefined influence parameters that represent situations by relying on singular value decomposition matrix. The parameter changing tendency is surveyed under derivative proposition isolate fault, where faulty actuator corresponding category magnitude are figured out. Based diagnosis, takes...

This paper proposes an output feedback trajectory tracking control based on the uncertainty and disturbance estimator (UDE) technique. The studied nonlinear system is single-input-single-output (SISO), bounded-input-bounded-output (BIBO), Lipschitz smooth. main idea that firstly approximated by a proper first-order linear plus lumped term, which estimated compensated through UDE. proposed technique modeling-free, only uses information of spectrum term. It also relaxes structural constraint...

In this paper, the uncertainty and disturbance estimator (UDE)-based control is adopted for a class of nonlinear systems with mismatched uncertainties input saturation. By integrating backstepping approach, robustness guaranteed by recursive structure backstepping. The "disturbance-like" terms which consist unknown dynamics, disturbances system intermediate tracking errors are estimated low-pass filters knowledge spectrum information. An auxiliary constructed to deal saturation while only...

Vanadium dioxide ( $VO_{2}$ ) undergoes a metal-insulator transition (MIT) around temperature close to 68° C, which enables many digital-like applications including memory devices, sensors, phase change switches, etc. However, the abruptness of MIT across sharp and narrow window limits its usage in development that demand an analog operation mode with continuously tunable properties. Achieving precise continuous tuning films will enable more powerful capable devices for different fields....

This paper proposes a new method for the tracking control problem of strict-feedback systems with mismatched disturbances. The method, called uncertainty disturbance estimator (UDE), is introduced into conventional backstepping scheme to handle disturbances due its excellent performance in handling uncertainties and yet simple scheme. dynamic surface (DSC) adopted overcome "explosion complexity" Compared existing work literature, deviation term between synthetic virtual system state, lumped...

Abstract Vanadium dioxide (VO2) undergoes a metal-insulator transition (MIT) at approximately 68 °C, with associated sharp changes in its physical (e.g., optical, electrical, and mechanical) properties. This behavior makes VO2 films of interest many potential applications, including memory devices, switches, sensors, optical modulators. For ON/OFF like digital an abrupt switching is ideal. However, to continuously change metal/insulator phase ratio for analog-like operation, the intrinsic...

Abstract The uncertainty and disturbance estimator (UDE)-based robust control has a two-degree-of-freedom nature through the design of error dynamics UDE filters. In conventional to handle periodic disturbances or mixed sinusoidal disturbances, high-order filters incorporated with internal model principle (IMP) time-delay (TDF) are adopted achieve asymptotic reference tracking rejection. this paper, new combined repetitive loop is proposed for UDE-based rejection both step disturbances....