In this paper a novel method is proposed for construction of an exponential observer for nonlinear system. The presented method is based on direct solution of dynamic error without any linearzing of nonlinear terms. Necessary and sufficient conditions for construction of direct observer are presented. Stability of the observer is checked using Lyapunov theorem. Also the ability of this observer...

This paper proposes an improved equivalent-input-disturbance (IEID) approach to further suppress the exogenous disturbances. A predictor linear tracking differentiator (PLTD) is suggested as a replacement for first-order low-pass filter in traditional EID method and constructs IEID approach. The controller based on includes PLTD, Luenberger state observer, internal model of input signal feedbac...

This paper proposes the observer-based proportional-integral-derivative control of positive multi-agent systems. First, a observer is constructed for considered systems in terms matrix decomposition approach. Then, novel protocol framework proposed based on an improved observer. By using copositive Lyapunov function, positivity and consensus are achieved. The corresponding gain matrices designe...

In This paper, we present a robust high gain output feedback control for a class of uniformly observable and controllable nonlinear systems. Our main goal here is to apply an output feedback controller which regulates the output of the plant to a constant reference. While the smooth state feedback control law is constructed based on the use of a high gain sliding mode controller, the estimation...

Eye movements function to bring detailed information onto the high-resolution region of the retina. Previous research has shown that human observers select fixation points that maximize information acquisition and minimize target location uncertainty. In this study, we ask whether human observers choose the saccade endpoint that maximizes gain when there are explicit rewards associated with cor...

In this paper, we are concerned with a cascade of ODE-wave systems with the control actuator-matched disturbance at the boundary of the wave equation. We use the sliding mode control (SMC) technique and the active disturbance rejection control method to overcome the disturbance, respectively. By the SMC approach, the disturbance is supposed to be bounded only. The existence and uniqueness of so...

A robust observer-based leader-following consensus control for linear multi-agent systems subject to external disturbance and measurement noise is developed. The $$H_\infty $$ criterion implemented guarantee stability robustness of the synchronization error estimation through Lyapunov approach. set matrix inequalities are obtained compute observer gain matrices. To show its effectiveness, propo...

Much of the recent work on robust control or observer design has focused on preservation of stability of the controlled system or the convergence of the observer in the presence of parameter perturbations in the plant equations. The present work addresses the important problem of resilience or nonfragility which is the maintenance of convergence or performance when the observer is erroneously i...

An observer based variable sampling period phase locked loop is introduced for grid connected systems. The composite observer acts as an efficient estimator of the fundamental components from a periodic input signal rich in DC and harmonics. The observer gains are designed using pole placement technique, which inherently ensures the stability of this estimator. Even under drift frequency, a con...