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Robust nonlinear observer design for actuator fault detection in diesel engines

Boulaid Boulkroune, Issam Djemili, Abdel Aitouche, Vincent Cocquempot (2013)

International Journal of Applied Mathematics and Computer Science

This paper is concerned with actuator fault detection in nonlinear systems in the presence of disturbances. A nonlinear unknown input observer is designed and the output estimation error is used as a residual for fault detection. To deal with the problem of high Lipschitz constants, a modified mean-value theorem is used to express the nonlinear error dynamics as a convex combination of known matrices with time-varying coefficients. Moreover, the disturbance attenuation is performed using a modified...

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 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...

Robust quasi NID aircraft 3D flight control under sensor noise

Marian J. Błachuta, Valery D. Yurkevich, Konrad Wojciechowski (1999)

Kybernetika

In the paper the design of an aircraft motion controller based on the Dynamic Contraction Method is presented. The control task is formulated as a tracking problem for Euler angles, where the desired decoupled output transients are accomplished under assumption of high-level, high-frequency sensor noise and incomplete information about varying parameters of the system and external disturbances. The resulting controller has a simple form of a combination of a low-order linear dynamical system and...

RTC-method for the control of nuclear reactor power

Wajdi A. Ratemi (1998)

Kybernetika

In this paper, a new concept of the Reactivity Trace Curve (RTC) for reactor power control is presented. The concept is demonstrated for a reactor model with one group of delayed neutrons, where the reactivity trace curve is simply a closed form exponential solution of the RTC-differential equation identifier. An extended reactor model of multigroup (six groups) of delayed neutrons is discussed for power control using the RTC-method which is based on numerical solution of the governing equation...

Safety regulations and fuzzy-logic control to nuclear reactors.

Da Ruan (2000)

Mathware and Soft Computing

We present an R&D project on fuzzy-logic control applicatios tor the Belgian Nuclear Reactor 1 (BR1) at the Belgian Nuclear Research Centre (SCK·CEN). The project started in 1995 and aimed at investigating the added value of fuzzy logic control for nuclear reactors. We first review some relevant literature on fuzzy logic control in nuclear reactors, then present the state-of-the-art of the BR1 project, with an understanding of the safety requirements for this real fuzzy-logic control application...

Sampled weighted attraction control of distributed thermal scan welding

Charalabos C. Doumanidis (1999)

Kybernetika

This article addresses the problem of distributed-parameter control for a class of infinite-dimensional manufacturing processes with scanned thermal actuation, such as scan welding. This new process is implemented on a robotic GTAW laboratory setup with infrared pyrometry, and simulated by a flexible numerical computation program. An analytical linearized model, based on convolution of Green’s fields, is expressed in multivariable state-space form, with its time-variant parameters identified in-process....

Self-replication processes in nanosystems of informatics

Stefan Węgrzyn, Ryszard Winiarczyk, Lech Znamirowski (2003)

International Journal of Applied Mathematics and Computer Science

Recent research on the nanotechnological processes of molecular products and object synthesis as well as research on the nanosystems of informatics, stimulates the development of technical systems of informatics. Until now, they have been used mainly for computational tasks when, similarly to biological organisms, they allowed the development of self-replicating products and complete objects. One can focus here on the model of a circulation of materials, information and energy in a biological cell,...

(s,S)-type policy for a production inventory problem with limited backlogging and with stockouts

Ryszarda Rempała (1997)

Applicationes Mathematicae

A production inventory problem with limited backlogging and with stockouts is described in a discrete time, stochastic optimal control framework with finite horizon. It is proved by dynamic programming methods that an optimal policy is of (s,S)-type. This means that in every period the policy is completely determined by two fixed levels of the stochastic inventory process considered.

Stability analysis of a three-dimensional energy demand-supply system under delayed feedback control

Kun-Yi Yang, Ling-Li Zhang, Jie Zhang (2015)

Kybernetika

This paper considers a three-dimensional energy demand-supply system which typically demonstrates the relationship between the amount of energy supply and that of energy demand for the two regions in China. A delayed feedback controller is proposed to stabilize the system which was originally unstable even under some other controllers. The stability properties of the equilibrium points are subsequently analyzed and it is found that the Hopf bifurcation appears under some conditions. By using the...

Switching LPV control design with MDADT and its application to a morphing aircraft

Yong He, Chunjuan Li, Weiguo Zhang, Jingping Shi, Yongxi Lü (2016)

Kybernetika

In flight control of a morphing aircraft, the design objective and the dynamics may be different in its various configurations. To accommodate different performance goals in different sweep wing configurations, a novel switching strategy, mode dependent average dwell time (MDADT), is adopted to investigate the flight control of a morphing aircraft in its morphing phase. The switching signal used in this note is more general than the average dwell time (ADT), in which each mode has its own ADT. Under...

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