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Decomposition of the symptom observation matrix and grey forecasting in vibration condition monitoring of machines

Czesław Cempel (2008)

International Journal of Applied Mathematics and Computer Science

With the tools of modern metrology we can measure almost all variables in the phenomenon field of a working machine, and many of the measured quantities can be symptoms of machine conditions. On this basis, we can form a symptom observation matrix (SOM) intended for condition monitoring and wear trend (fault) identification. On the other hand, we know that contemporary complex machines may have many modes of failure, called faults. The paper presents a method of the extraction of the information...

Decomposition of vibration signals into deterministic and nondeterministic components and its capabilities of fault detection and identification

Tomasz Barszcz (2009)

International Journal of Applied Mathematics and Computer Science

The paper investigates the possibility of decomposing vibration signals into deterministic and nondeterministic parts, based on the Wold theorem. A short description of the theory of adaptive filters is presented. When an adaptive filter uses the delayed version of the input signal as the reference signal, it is possible to divide the signal into a deterministic (gear and shaft related) part and a nondeterministic (noise and rolling bearings) part. The idea of the self-adaptive filter (in the literature...

Design of microprogrammed controllers to be implemented in FPGAs

Remigiusz Wiśniewski, Alexander Barkalov, Larisa Titarenko, Wolfgang A. Halang (2011)

International Journal of Applied Mathematics and Computer Science

In the article we propose a new design method for microprogrammed controllers. The traditional structure is improved by modifying internal modules and connections. Such a solution allows reducing the total number of logic elements needed for implementation in programmable structures, especially Field Programmable Gate Arrays (FPGAs). Detailed results of experiments show that on the average the application of the proposed methods yields up to 30% savings as far as the destination device is considered....

Design of reaching phase for variable structure controller based on SVD method

Goshaidas Ray, Sitansu Dey (2004)

Kybernetika

This paper considers a design of variable structure with sliding mode controller for a class of uncertain dynamic system based on Singular Value Decomposition (SVD) method. The proposed method reduces the number of switching gain vector components and performs satisfactorily while the external disturbance does not satisfy the matching conditions. Subsequently the stability of the global system is studied and furthermore, the design of switched gain matrix elements based on fuzzy logic approach provides...

Designing a ship course controller by applying the adaptive backstepping method

Anna Witkowska, Roman Śmierzchalski (2012)

International Journal of Applied Mathematics and Computer Science

The article discusses the problem of designing a proper and efficient adaptive course-keeping control system for a seagoing ship based on the adaptive backstepping method. The proposed controller in the design stage takes into account the dynamic properties of the steering gear and the full nonlinear static maneuvering characteristic. The adjustable parameters of the achieved nonlinear control structure were tuned up by using the genetic algorithm in order to optimize the system performance. A realistic...

Detection and identification of loss of efficiency faults of flight actuators

Daniel Ossmann, Andreas Varga (2015)

International Journal of Applied Mathematics and Computer Science

We propose linear parameter-varying (LPV) model-based approaches to the synthesis of robust fault detection and diagnosis (FDD) systems for loss of efficiency (LOE) faults of flight actuators. The proposed methods are applicable to several types of parametric (or multiplicative) LOE faults such as actuator disconnection, surface damage, actuator power loss or stall loads. For the detection of these parametric faults, advanced LPV-model detection techniques are proposed, which implicitly provide...

Disturbance observer based integral terminal sliding mode control for permanent magnet synchronous motor system

Junxiao Wang, Fengxiang Wang, Xianbo Wang, Li Yu (2019)

Kybernetika

This paper presents speed regulation issue of Permanent Magnet Synchronous Motor (PMSM) using a composite integral terminal sliding mode control scheme via a disturbance compensation technique. The PMSM q -axis and d -axis subsystems are firstly transformed into two linear subsystems by using feedback linearization technique, then, integral terminal sliding mode controller and finite-time controller are designed respectively. The proof of finite time stability are given for the PMSM closed-loop system....

Disturbance observer-based second order sliding mode attitude tracking control for flexible spacecraft

Chutiphon Pukdeboon, Anuchit Jitpattanakul (2017)

Kybernetika

This paper presents a composite controller that combines nonlinear disturbance observer and second order sliding mode controller for attitude tracking of flexible spacecraft. First, a new nonsingular sliding surface is introduced. Then, a second order sliding mode attitude controller is designed to achieve high-precision tracking performance. An extended state observer is also developed to estimate the total disturbance torque consisting of environmental disturbances, system uncertainties and flexible...

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