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Robust decoupling through algebraic output feedback in manipulation systems

Paolo Mercorelli (2010)

Kybernetika

This paper investigates the geometric and structural characteristics involved in the control of general mechanisms and manipulation systems. These systems consist of multiple cooperating linkages that interact with a reference member of the mechanism (the “object”) by means of contacts on any available part of their links. Grasp and manipulation of an object by the human hand is taken as a paradigmatic example for this class of manipulators. Special attention is devoted to the output specification...

Robust dynamic output feedback fault-tolerant control for Takagi-Sugeno fuzzy systems with interval time-varying delay via improved delay partitioning approach

Chao Sun, Fuli Wang, Xiqin He (2016)

Open Mathematics

This paper addresses the problem of robust fault-tolerant control design scheme for a class of Takagi-Sugeno fuzzy systems subject to interval time-varying delay and external disturbances. First, by using improved delay partitioning approach, a novel n-steps iterative learning fault estimation observer under H ∞ constraint is constructed to achieve estimation of actuator fault. Then, based on the online estimation information, a fuzzy dynamic output feedback fault-tolerant controller considered...

Robust exponential stability of a class of nonlinear systems

Vojtech Veselý, Danica Rosinová (1998)

Kybernetika

The paper addresses the problem of design of a robust controller for a class of nonlinear uncertain systems to guarantee the prescribed decay rate of exponential stability. The bounded deterministic uncertainties are considered both in a studied system and its input part. The proposed approach does not employ matching conditions.

Robust Feedback Control Design for a Nonlinear Wastewater Treatment Model

M. Serhani, N. Raissi, P. Cartigny (2009)

Mathematical Modelling of Natural Phenomena

In this work we deal with the design of the robust feedback control of wastewater treatment system, namely the activated sludge process. This problem is formulated by a nonlinear ordinary differential system. On one hand, we develop a robust analysis when the specific growth function of the bacterium μ is not well known. On the other hand, when also the substrate concentration in the feed stream sin is unknown, we provide an observer of system and propose a design of robust feedback control in...

Robust hierarchical sliding mode control with state-dependent switching gain for stabilization of rotary inverted pendulum

Muhammad Idrees, Shah Muhammad, Saif Ullah (2019)

Kybernetika

The rotary inverted pendulum (RIP) system is one of the fundamental, nonlinear, unstable and interesting benchmark systems in the field of control theory. In this paper, two nonlinear control strategies, namely hierarchical sliding mode control (HSMC) and decoupled sliding mode control (DSMC), are discussed to address the stabilization problem of the RIP system. We introduced HSMC with state-dependent switching gain for stabilization of the RIP system. Numerical simulations are performed to analyze...

Robust multisensor fault tolerant model-following MPC design for constrained systems

Alain Yetendje, Maria M. Seron, José A. De Doná (2012)

International Journal of Applied Mathematics and Computer Science

In this paper, a robust fault-tolerant control strategy for constrained multisensor linear systems, subject to sensor faults and in the presence of bounded state and output disturbances, is proposed. The scheme verifies that, for each sensors-estimator combination, suitable residual variables lie inside pre-computed sets and selects a more appropriate combination based on a chosen criterion. An active fault tolerant output feedback controller yields an MPC-based control law and, by means of the...

Robust Observer-based control of switched nonlinear systems with quantized and sampled output

Carlos Perez, Manuel Mera (2015)

Kybernetika

This paper deals with the robust stabilization of a class of nonlinear switched systems with non-vanishing bounded perturbations. The nonlinearities in the systems satisfy a quasi-Lipschitz condition. An observer-based linear-type switching controller with quantized and sampled output signal is considered. Using a dwell-time approach and an extended version of the invariant ellipsoid method (IEM) sufficient conditions for stability in a practical sense are derived. These conditions are represented...

Robust observer-based finite-time H control designs for discrete nonlinear systems with time-varying delay

Yali Dong, Huimin Wang, Mengxiao Deng (2021)

Kybernetika

This paper investigates the problem of observer-based finite-time H control for the uncertain discrete-time systems with nonlinear perturbations and time-varying delay. The Luenberger observer is designed to measure the system state. The observer-based controller is constructed. By constructing an appropriated Lyapunov-.Krasovskii functional, sufficient conditions are derived to ensure the resulting closed-loop system is H finite-time bounded via observer-based control. The observer-based controller...

Robust optimal PID controller design for attitude stabilization of flexible spacecraft

Chutiphon Pukdeboon (2018)

Kybernetika

This paper presents a novel robust optimal control approach for attitude stabilization of a flexible spacecraft in the presence of external disturbances. An optimal control law is formulated by using concepts of inverse optimal control, proportional-integral-derivative control and a control Lyapunov function. A modified extended state observer is used to compensate for the total disturbances. High-gain and second order sliding mode algorithms are merged to obtain the proposed modified extended state...

Robust pole placement for second-order systems: an LMI approach

Didier Henrion, Michael Šebek, Vladimír Kučera (2005)

Kybernetika

Based on recently developed sufficient conditions for stability of polynomial matrices, an LMI technique is described to perform robust pole placement by proportional-derivative feedback on second-order linear systems affected by polytopic or norm-bounded uncertainty. As illustrated by several numerical examples, at the core of the approach is the choice of a nominal, or central quadratic polynomial matrix.

Robust prevention of limit cycles for robustly decoupled car steering dynamics

Jürgen Ackermann, Tilman Bünte (1999)

Kybernetika

Considerable safety benefits are achieved by robustly decoupling the lateral and yaw motions of a car with active steering. Robust unilateral decoupling requires an actuator to generate an additional front wheel steering angle. However, introducing actuators to closed loop systems may cause limit cycles due to actuator saturation and rate limits. Such limit cycles are intolerable w.r.t. safety and comfort. By introducing a simple nonlinear modification of the control law, this paper proposes a remedy...

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