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Algebraic fault detection and isolation for parabolic distributed–parameter systems using modulation functions

IFAC-PapersOnLine 2016年第8期49卷 162-167页

作者： Fischer, F. Deutscher, J. Lehrstuhl fur Regelungstechnik Universität Erlangen-Nürnberg Cauerstraße 7 ErlangenD-91058 Germany

In this article an algebraic approach to the fault detection for parabolic distributed-parameter systems is described. The modulation functions approach is used to obtain an algebraic fault detection equation, that only depends on known signals and the fault. Assuming piecewise constant faults, this allows the detection of the absolute fault value without any system approximation. Furthermore, different additional requirements, such as fault isolation or decoupling of disturbances can be met. The corresponding modulation functions are obtained by the realization of a set-point change for their signal models. Hence, the modulation functions can be determined using existing results to the motion planning and open-loop control for distributed-parameter systems. The proposed fault detection and isolation method is illustrated for a faulty heat conductor. © 2016

关键词： Fault detection Algebra Distributed parameter control systems modulation Motion planning Distributed parameter systems Fault isolation modulation functions Setpoints Trajectory Planning

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Prototypes and modulation functions of Classical and Novel Configurations of Optical Chopper Wheels

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LATIN AMERICAN JOURNAL OF SOLIDS AND STRUCTURES 2013年第1期10卷 5-18页

作者： Duma, Virgil-Florin Aurel Vlaicu Univ Arad Fac Engn Optomechatron Grp 3OM Arad 310130 Romania

Optical choppers with rotating wheels are some of the most used macroscopic optomechatronic devices for the controlled modulation, attenuation or obscuration of light in a wide area of applications. We discuss and compare the modulation functions produced by two types of chopper wheels: the classical device, with windows with linear edges, and the eclipse chopper (with windows with circular edges) that, to the best of our knowledge, we have introduced. This discussion is based on the analysis and the design we have previously developed for these various devices, for top-hat (constant over the entire section) light beam distributions. While the comparison of the different shapes of transmitted signals allows for the proper choice of the most appropriate device and parameters to obtain the modulation function that is fit for a certain application, the present work also presents the mechanical setup we have designed and manufactured for testing choppers with rotating wheels. A series of prototype wheels with different, optimized profiles were obtained for the purpose. The simulation and the electro-erosion programs for the wire electro-erosion of aluminum plates to manufacture the wheels are presented. An advantageous double wheel solution has been developed to obtain wheels with windows of different shapes and sizes, and the testing of this final assembly concludes the study.

关键词： optomechatronics optical devices choppers modulation functions modeling simulations mechanical design prototypes manufacturing electro-erosion process

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modulation-Function-Based Data-Driven Design of Fault Detection Systems for Continuous-Time LTI Systems 13th

Modulation-Function-Based Data-Driven Design of Fault Detect...

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13th IFAC Symposium on Dynamics and Control of Process Systems, including Biosystems (DYCOPS)

作者： Jahn, Benjamin Shardt, Yuri A. W. Tech Univ Ilmenau Dept Automat Engn D-98684 Ilmenau Germany MOTEON GmbH D-98693 Ilmenau Germany

In this paper, a data-driven or model-free approach is presented to design a fault detection system of continuous-time linear time-invariant (LTI) systems based on input and output data in the time domain. The main idea is to directly identify the subspaces and their related matrices relevant for parity-space-based residual generation based on a modulated output equation by use of modulation functions and their properties. Therefore, the explicit model identification of the process for a model-based approach in a conventional two-step procedure can be avoided saving design effort especially for large-scale systems. A simulation of the resulting fault detection system is provided showing the effectiveness of the design approach. Copyright (C) 2022 The Authors.

关键词： Fault Detection modulation functions Subspace Methods Residual Generation Parity Space Model-Free Data-Driven

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X-ray beam experiment for the Hard X-ray Imager onboard ASO-S

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NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT 2023年 1053卷

作者： Jiang, Xian-Kai Zhang, Zhe Hu, Yi-Ming Wang, Hao-Xiang Liu, Wei Zhang, Yong-Qiang Zhang, Yan Wu, Jian Chen, Deng-Yi Chinese Acad Sci Purple Mt Observ 10 Yuanhua Rd Nanjing 210023 Peoples R China Univ Sci & Technol China Sch Astron & Space Sci Hefei 230026 Peoples R China

The Hard X-ray Imager (HXI) is one of the scientific payloads onboard the Advanced Space-based Solar Observatory. As a telescope using Fourier space modulation, it contains fine sub-collimators to reach high angular resolution. The X-ray resolution of HXI needs to be verified on the ground before its launch. Therefore, an X-ray beam experiment was performed to evaluate the modulation capabilities of each sub-collimator in HXI. The X-ray beam facility for this experiment consisted of an X-ray machine with a 0.4 mm-diameter spot, a 26-meter beam tube with an adjustable diaphragm at the end to control the parallelism of the beam, and an experimental platform that could translate and horizontally rotate the instrument on it with high precision. A strategy for measuring these sub-collimators was then developed theoretically. Additionally, the stability of the instrument and the environment were monitored throughout the experiment. The results of the successful experiment are presented in this paper. The relevant parameters fitted from the measured modulation functions agree well with theoretical predictions. This proves the resolving ability of the HXI meets the requirements. The research also illustrates some side effects due to different incident energies and strengtheners.

关键词： X-ray telescope Collimator modulation functions X-ray beam experiment

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modulation-Function-Based Finite-Horizon Sensor Fault Detection for Salient-Pole PMSM using Parity-Space Residuals 19

Modulation-Function-Based Finite-Horizon Sensor Fault Detect...

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19th IFAC Symposium on System Identification (SYSID)

作者： Jahn, Benjamin Shardt, Yuri A. W. Tech Univ Ilmenau Dept Automat Engn D-98684 Ilmenau Germany

An online model-based fault detection and isolation method for salient-pole permanent magnet synchronous motors over a finite horizon is proposed. The proposed approach combines parity-space-based residual generation and modulation-function-based filtering. Given the polynomial model equations, the unknown variables (i.e. the states, unmeasured inputs) are eliminated resulting in analytic redundancy relations used for residual generation. Furthermore, in order to avoid needing the derivatives of measured signals required by such analytic redundancy relations, a modulation-function-based evaluation is proposed. This results in a finite-horizon filtered version of the original residual. The fault detection and isolation method is demonstrated using simulation of various fault scenarios for a speed controlled salient motor showing the effectiveness of the presented approach. Copyright (C) 2021 The Authors.

关键词： Permanent Magnet Synchronous Motor Sensor Fault Detection Analytic Redundancy Relations modulation functions

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modulation-Function-Based Data-Driven Design of Fault Detection Systems for Continuous-Time LTI Systems

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IFAC-PapersOnLine 2022年第7期55卷 562-567页

作者： Benjamin Jahn Yuri A.W. Shardt Department of Automation Engineering Technical University of Ilmenau D-98684 Ilmenau Germany MOTEON GmbH D-98693 Ilmenau Germany

关键词： Fault Detection modulation functions Subspace Methods Residual Generation Parity Space Model-Free Data-Driven

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modulation-Function-Based Finite-Horizon Sensor Fault Detection for Salient-Pole PMSM using Parity-Space Residuals

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IFAC-PapersOnLine 2021年第7期54卷 61-66页

作者： Benjamin Jahn Yuri A.W. Shardt Department of Automation Engineering Technical University of Ilmenau D- 98684 Ilmenau Germany

关键词： Permanent Magnet Synchronous Motor Sensor Fault Detection Analytic Redundancy Relations modulation functions

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Characterizing modulated structures with first-principles calculations: a unified superspace scheme of ordering in mullite

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ACTA CRYSTALLOGRAPHICA A-FOUNDATION AND ADVANCES 2019年第2期75卷 260-272页

作者： Klar, Paul Benjamin Etxebarria, Inigo Madariaga, Gotzon Univ Basque Country UPV EHU Fac Ciencia & Tecnol Dept Fis Mat Condensada Apartado 644 E-48080 Bilbao Spain Univ Basque Country UPV EHU Fac Ciencia & Tecnol Dept Fis Aplicada 2 Apartado 644 E-48080 Bilbao Spain

The benefit of computational methods applying density functional theory for the description and understanding of modulated crystal structures is investigated. A method is presented which allows one to establish, improve and test superspace models including displacive and occupational modulation functions from firstprinciples calculations on commensurate structures. The total energies of different configurations allow one to distinguish stable and less stable structure models. The study is based on a series of geometrically optimized superstructures of mullite (A(l4+2x)Si(2-2x)O(10-x)) derived from the superspace group Pham(alpha 01/2)0ss. Despite the disordered and structurally complex nature of mullite, the calculations on ordered superstructures are very useful for determining the ideal Al/Si ordering in mullite, extracting atomic modulation functions as well as understanding the SiO2-Al2O3 phase diagram. The results are compared with experimentally established models which confirm the validity and utility of the presented method.

关键词： density functional theory (DFT) superspace modulation functions Al/Si ordering silicates mullite

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Modeling of modulation functions of different configurations of optical chopper wheels

Modeling of modulation functions of different configurations...

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Conference on Modeling Aspects in Optical Metrology III

作者： Duma, V. -F. Nicolov, M. F. Kiss, M. Ilca, T. Demian, D. Szantho, L. Aurel Vlaicu Univ Arad Fac Engn Res Grp 3OM Arad 310130 Romania

ISBN: (纸本)9780819486790

We present in this paper our results regarding the modeling of the modulation functions of the light flux of optical choppers working with top-hat (constant) light beam distributions. Two configurations of chopper wheels are considered: with windows with linear and with circular margins (the latter, to the best of our knowledge, we have introduced, works as an "eclipse" chopper). A rigorous analytical modeling has been performed for each type of device. For the first configuration, of windows with linear margins, all the four possible relationships between the diameter of the beam in the plane of the wheel and the dimensions of the window of the chopper have been considered and are discussed: (i) large wing and focused beam [in the plane of the wheel];(ii) large wing and beam of finite diameter in the plane of the wheel, but with a wing large enough to cover the section of the beam;(iii) narrow wing, finite diameter beam and large windows, so there is only one wing at a time in front of the beam section;(iv) narrow wings and windows, so there are more wings at a time in front of the beam section. A recent study covered experimentally case (ii) presented above, obtaining a particular signal function (with an approximate trapezoidal profile). The second and more general wheel configuration that we have proposed in a previous study, with windows with circular margins (for which by example choppers with circular windows are a particular case) is also discussed. Both outwards and inwards circular margins are considered. The modulation functions of this second type of devices are also derived, studied and compared to those for the first, classical types of wheels (with windows with linear margins), which are but a particular case of this second type of chopper. From this study, the various profiles of the function of the transmitted flux are obtained: rectangular, approximate trapezoidal, approximate triangular, sinusoidal, and with non-null values. The possible geometrie

关键词： Optical devices choppers opto-mechanics chopper wheels modeling modulation functions

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Optomechatronic Choppers with Rotating Elements: Design Programs 12

Optomechatronic Choppers with Rotating Elements: Design Prog...

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12th International Conference on Dynamical Systems-Theory and Applications (DSTA)

作者： Cira, O. Duma, V. -F. Aurel Vlaicu Univ Arad Arad Romania

ISBN: (纸本)9783319082653

Choppers are most used devices for the modulation of light. We have developed a unitary theory of the optical choppers with rotating wheels working with top-hat laser beams (with constant intensity distribution). A novel type of chopper has been introduced, with windows with non-linear edges. The different modulation functions (of the transmitted light flux) were obtained. From this analysis, design programs are developed and presented in this study to tackle with the diverse cases represented by the chopper configurations and by their constructive and functional parameters. Numerical simulations and modeling are carried out based on the mathematical theory we have previously developed. Rules of thumb result to choose the most appropriate type of device and its characteristic parameters with regard to the particular requirements of a specific application. Top-hat (with constant intensity), Gaussian, and Bessel laser beams are considered in this study.

关键词： Optomechatronics Optical devices Choppers Laser beams Top-hat beams Gaussian beams modulation functions Analysis Optomechatronics Design programs

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