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Article
Publication date: 27 July 2012

Anupam Das, J. Maiti and R.N. Banerjee

Monitoring of a process leading to the detection of faults and determination of the root causes are essential for the production of consistent good quality end products with…

1797

Abstract

Purpose

Monitoring of a process leading to the detection of faults and determination of the root causes are essential for the production of consistent good quality end products with improved yield. The history of process monitoring fault detection (PMFD) strategies can be traced back to 1930s. Thereafter various tools, techniques and approaches were developed along with their application in diversified fields. The purpose of this paper is to make a review to categorize, describe and compare the various PMFD strategies.

Design/methodology/approach

Taxonomy was developed to categorize PMFD strategies. The basis for the categorization was the type of techniques being employed for devising the PMFD strategies. Further, PMFD strategies were discussed in detail along with emphasis on the areas of applications. Comparative evaluations of the PMFD strategies based on some commonly identified issues were also carried out. A general framework common to all the PMFD has been presented. And lastly a discussion into future scope of research was carried out.

Findings

The techniques employed for PMFD are primarily of three types, namely data driven techniques such as statistical model based and artificial intelligent based techniques, priori knowledge based techniques, and hybrid models, with a huge dominance of the first type. The factors that should be considered in developing a PMFD strategy are ease in development, diagnostic ability, fault detection speed, robustness to noise, generalization capability, and handling of nonlinearity. The review reveals that there is no single strategy that can address all aspects related to process monitoring and fault detection efficiently and there is a need to mesh the different techniques from various PMFD strategies to devise a more efficient PMFD strategy.

Research limitations/implications

The review documents the existing strategies for PMFD with an emphasis on finding out the nature of the strategies, data requirements, model building steps, applicability and scope for amalgamation. The review helps future researchers and practitioners to choose appropriate techniques for PMFD studies for a given situation. Further, future researchers will get a comprehensive but precise report on PMFD strategies available in the literature to date.

Originality/value

The review starts with identifying key indicators of PMFD for review and taxonomy was proposed. An analysis was conducted to identify the pattern of published articles on PMFD followed by evolution of PMFD strategies. Finally, a general framework is given for PMFD strategies for future researchers and practitioners.

Details

International Journal of Quality & Reliability Management, vol. 29 no. 7
Type: Research Article
ISSN: 0265-671X

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Article
Publication date: 2 July 2018

Hamed Pourazad, Javad Askari and Saeed Hosseinnia

Increasing commercial applications for small unmanned aircraft create growing challenges in providing safe flight conditions. The conventional measures to detect icing are either…

92

Abstract

Purpose

Increasing commercial applications for small unmanned aircraft create growing challenges in providing safe flight conditions. The conventional measures to detect icing are either expensive, energy consuming or heavy. The purpose of this paper is to develop a fault identification and isolation scheme using unknown input observers to detect and isolate actuator and structural faults in simultaneous occurrence.

Design/methodology/approach

The fault detection scheme is based on a deviation in system parameters due to icing and lock-in-place (LIP), two faults from different categories with similar indications that require different reconfiguration actions. The obtained residual signals are selected to be triggered by desired faults, while insensitive to others.

Findings

The proposed observer is sensitive to both actuator and structural faults, and distinguishes simultaneous occurrences by insensitivity to LIP in selected residue signals. Simulation results confirm the success of the proposed system in the presence of uncertainty and disturbance.

Research limitations/implications

The fault detection and isolation scheme proposed here is based on the linear model of a winged aircraft, the Aerosonde. Moreover, the faults are applied to rudder and aileron in simulations, but the design procedure for other models is provided. The designed scheme could be further implemented on a non-linear aircraft model.

Practical implications

Applying the proposed icing detection scheme increases detection system reliability, since fault isolation enables timely reconfiguration schemes.

Originality/value

The observers proposed in previous papers detected icing fault but were not insensitive to actuator faults.

Details

International Journal of Intelligent Unmanned Systems, vol. 6 no. 3
Type: Research Article
ISSN: 2049-6427

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Article
Publication date: 1 September 2002

S.A. Al‐Mawsawi, M.R. Qader and K.L. Lo [1]

In recent years it has been illustrated that the Unified Power Flow Controller (UPFC) installation location plays an important role in effecting nonlinearly its steady state…

509

Abstract

In recent years it has been illustrated that the Unified Power Flow Controller (UPFC) installation location plays an important role in effecting nonlinearly its steady state performance. A Pulse Width Modulation (PWM) based UPFC used as a voltage regulator is modeled and analyzed to investigate its optimal position in the transmission line. From the simulation results it is demonstration that by varying the modulation index of the device it can control the distribution of the active and reactive power flows. In addition, this paper deals with the definition and simulation of the control strategy of the closed‐loop UPFC with a series compensation block when it operates as a terminal voltage regulator using Electromagnetic Transients Program (EMTP). The design and simulation of two types of digital controller strategies for the study system in this paper have been carried out. The dynamic performance in terms of speed stability, accuracy, robustness and simplicity of a PI controller with gain scheduling and a fuzzy logic controller have been tested and compared.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 21 no. 3
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 1 March 1941

R. Isermann and E. Beck

In the spring of 1937, take‐off tests down slopes of various gradients were carried out by the Flug‐technisch Institut. The gradients reached up to 35 deg. The experimental…

34

Abstract

In the spring of 1937, take‐off tests down slopes of various gradients were carried out by the Flug‐technisch Institut. The gradients reached up to 35 deg. The experimental results are compared with calculation. The efficiency of this method of take‐off, together with its advantages and disadvantages, is investigated.

Details

Aircraft Engineering and Aerospace Technology, vol. 13 no. 3
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 25 January 2008

Jia‐hui Luan and Ting‐di Zhao

This paper aims to present a novel fault estimator design scheme, in order to improve the practicability of the fault estimation.

328

Abstract

Purpose

This paper aims to present a novel fault estimator design scheme, in order to improve the practicability of the fault estimation.

Design/methodology/approach

The paper first transforms the system state into three parts. Then a reduced‐observer is designed for an unknown input and fault‐free system, and the observer can get no bias error in the state estimation. So the estimator can get the exact estimation for the unknown input and fault of the actuator.

Findings

By using this approach it is found that the condition of the estimator is weaker than other observers. It is a qualified and simple and straightforward approach to be applied in wide domains.

Research limitations/implications

It should be noted that the sensors should be perfectly reliable. The maximum number of disturbances which can be decoupled cannot be larger than the number of independent actuators.

Practical implications

It is a very useful approach to solve the problem that the actuator is contaminated by disturbances.

Originality/value

The paper uses a transformation to divide the state into three parts. By estimating the part that is not affected by the disturbance and fault, it gets the exact estimation for the unknown input and fault of the actuator. The design condition of the reduced‐order observer which is proposed is weaker than others.

Details

Aircraft Engineering and Aerospace Technology, vol. 80 no. 1
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 12 September 2024

Shihui Tian and Ke Xu

The purpose of this paper is to investigate the fault estimation issue of nonlinear dynamical systems via distributed sensor networks. Furthermore, based on the communication…

22

Abstract

Purpose

The purpose of this paper is to investigate the fault estimation issue of nonlinear dynamical systems via distributed sensor networks. Furthermore, based on the communication topology of sensor networks, the nonfragile design strategy considering the gain fluctuation is also adopted for distributed fault estimators.

Design/methodology/approach

By means of intensive dynamical model transformation, sufficient conditions with disturbance attenuation performance are established to design desired fault estimator gains with the help of convex optimization.

Findings

A novel distributed fault estimation framework for a class of nonlinear dynamical systems is established over a set of distributed sensor networks, where sampled data of sensor nodes via local information exchanges can be used for more efficiency.

Originality/value

The proposed distributed fault estimator gain fluctuations are taken into account for the nonfragile strategy, such that the distributed fault estimators are more applicable for practical sensor networks implementations. In addition, an illustrative example with simulation results are provided to validate the effectiveness and applicableness of the developed distributed fault estimation technique.

Details

Robotic Intelligence and Automation, vol. 44 no. 6
Type: Research Article
ISSN: 2754-6969

Keywords

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Article
Publication date: 4 September 2017

Milos Milovancevic, Vlastimir Nikolic, Nenad T. Pavlovic, Aleksandar Veg and Sanjin Troha

The purpose of this study is to establish a vibration prediction of pellet mills power transmission by artificial neural network. Vibration monitoring is an important task for any…

140

Abstract

Purpose

The purpose of this study is to establish a vibration prediction of pellet mills power transmission by artificial neural network. Vibration monitoring is an important task for any system to ensure safe operations. Improvement of control strategies is crucial for the vibration monitoring.

Design/methodology/approach

As predictive control is one of the options for the vibration monitoring in this paper, the predictive model for vibration monitoring was created.

Findings

Although the achieved prediction results were acceptable, there is need for more work to apply and test these results in real environment.

Originality/value

Artificial neural network (ANN) was implemented as the predictive model while extreme learning machine (ELM) and back propagation (BP) learning schemes were used as training algorithms for the ANN. BP learning algorithm minimizes the error function by using the gradient descent method. ELM training algorithm is based on selecting of the input weights randomly of the ANN network and the output weight of the network are determined analytically.

Details

Assembly Automation, vol. 37 no. 4
Type: Research Article
ISSN: 0144-5154

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Article
Publication date: 5 January 2010

Mario Pacas, Sebastian Villwock, Piotr Szczupak and Henning Zoubek

The purpose of this paper is to summarize several identification methods for the automatic commissioning of electrical drives that are presented in different earlier papers of the…

514

Abstract

Purpose

The purpose of this paper is to summarize several identification methods for the automatic commissioning of electrical drives that are presented in different earlier papers of the same authors. This paper is intended as a contribution to the development of expert systems, taking into account parametric models of the mechanical and electrical subsystem as well as the corresponding parameter fitting.

Design/methodology/approach

Some system parameters, which are mandatory for the commissioning of electrical and mechanical systems are often not known. For their identification, a method based on the frequency response calculation utilizing the Welch method is now presented. The main focus of the work is directed to the measurement of the frequency response by exciting the system with pseudo‐random binary signals and to the subsequent procedure for the calculation of the corresponding parameter by utilizing the Levenberg‐Marquardt algorithm.

Findings

The presented identification procedure leads to outstanding results during the commissioning of the system as well as under normal operation conditions. The identification of the parameter of the mechanical and electrical systems is therefore possible during the commissioning of the drive as well as in running machines. Further, some restrictions regarding the measurement facilities are presented.

Originality/value

The presented identification procedure can be applied in a variety of conditions and can be applied for diagnostic tasks. New measurement and considerations regarding the restrictions of the applied method also under normal operation of the systems underline this fact.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 29 no. 1
Type: Research Article
ISSN: 0332-1649

Keywords

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Article
Publication date: 1 May 1939

H.H. Jackson

OF all modern engineering constructions, it is difficult to imagine a unit the components of which are more liable to general wear than the present‐day internal combustion and…

55

Abstract

OF all modern engineering constructions, it is difficult to imagine a unit the components of which are more liable to general wear than the present‐day internal combustion and compression ignition engines. The performances demanded of aero‐engines in particular, have instigated the enormous amount of research and investigation that has been made on the problem of reducing metallic wear under various conditions of temperature, load, atmosphere, etc. The importance of this problem is manifest when one reflects that the great majority of the components of the aero‐engine (with the exception of details, nuts, bolts, pins, etc.) are subject to continual wear in one form or another. In other words, the serviceable life of any engine is largely a function of the degree to which particular forms of wear have been minimized. While the question of adequate lubrication is undoubtedly of vital importance in reducing friction, the primary causes of wear are dependent upon the properties and surface conditions of the materials at their respective working temperatures. For the majority of components, the selection of material must necessarily be mainly decided by such considerations as yield point, compression strength, fatigue range, specific tenacity, maximum stress, resistance to scaling, thermal expansion, etc., and the question of wear is reckoned rather as a problem for which the metallurgist will find a treatment which can be suitably applied to the material. Thus we have seen evolved the many processes for surface‐hardening, and numerous anti‐friction materials, etc. It is interesting to review the present position of the practical applications of the science of reducing metallic friction, and to note tendencies of future developments.

Details

Aircraft Engineering and Aerospace Technology, vol. 11 no. 5
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 13 November 2019

Dustin Helm and Markus Timusk

The purpose of this paper is to demonstrate that by utilizing the relationship between redundant hardware components, inherent in parallel machinery, vibration-based fault…

159

Abstract

Purpose

The purpose of this paper is to demonstrate that by utilizing the relationship between redundant hardware components, inherent in parallel machinery, vibration-based fault detection methods can be made more robust to changes in operational conditions. This work reports on a study of fault detection on bearings operating in two parallel subsystems that experience identical changes in speed and load.

Design/methodology/approach

This study was carried out using two identical subsystems that operate on the same duty cycle. The systems were run with both healthy and a variety of common bearing faults. The faults were detected by analyzing the residual between the features of the two vibration signatures from the two subsystems.

Findings

This work found that by utilizing this relationship in parallel operating machinery the fault detection process can be improved. The study looked at several different types of feature vector and found that, in this case, features based on envelope analysis or autoregressive model work the best, whereas basic statistical features did not work as well.

Originality/value

The proposed method can be a computationally efficient and simple solution to monitoring non-stationary machinery where there is hardware redundancy present. This method is shown to have some advantages over non-parallel approaches.

Details

Journal of Quality in Maintenance Engineering, vol. 26 no. 2
Type: Research Article
ISSN: 1355-2511

Keywords

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