Wyniki wyszukiwania - BazTech

1

Using the Pulsed Eddy Current Techniques for Monitoring the Aircraft Structure Condition

Lysenko Iuliia, Kuts Yurii, Uchanin Valentyn, Protasov Anatoliy, Petryk Valentyn, Alexiev Alexander

Transactions on Aerospace Research

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2023

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Nr 1 (270)

22--31

EN

It is known that during operation, the aircraft construction materials are exposed to significant mechanical loads and changes in temperature for a very short period of time. All this leads to various defects and damages in the aircraft assemblies and units that need to be inspected for the safe operation of the aircraft, their assemblies, and units. In some cases, the implementation of inspection or diagnostic is accompanied by the emergence of technical difficulties caused by the large size of the aircraft assemblies or units and limited access to their local places. Under such conditions, ensuring the possibility of diagnosis in hard-to-reach places of the object becomes especially important. The problem can be solved by applying wireless technologies. It allows spatial separation of the probes and the signal processing units, which simplifies the scanning of the surfaces of the large assemblies and units in hard-to-reach places. In this article, the description of the developed wireless system of eddy current inspection for aircraft structural materials is given. Experimental results of object scanning are given in the form of a distribution of the values of probe signal informative parameters (amplitude, frequency and decrement) along the object coordinates.

2

Automated Eddy Current System for Aircraft Structure Inspection

Lysenko Iuliia, Kuts Yurii, Petryk Valentyn, Malko Volodymyr, Melnyk Andrii

Transactions on Aerospace Research

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2023

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Nr 4 (273)

33--40

EN

Aircraft part diagnostics are crucial during both production and maintenance, with eddy current nondestructive testing (ECNDT) being the method of choice due to its cost-effectiveness, informativeness, productivity, and reliability. ECNDT excels regardless of surface condition or coatings. It’s employed for diagnosing various aircraft components, necessitating diverse transducer types, excitation modes, and advanced signal processing. To improve ECNDT, this article explores integrating harmonic and impulse excitation modes in a single tool to enhance informativeness. Building upon a wireless eddy current system, the authors propose a comprehensive method for processing and displaying information suitable for object condition monitoring systems. The system includes automated transducer mode control and experimental data processing algorithms. The constant expansion of tested objects and new materials underscores the need to enhance the theoretical foundations of eddy current non-destructive testing, refine signal processing techniques, and identify informative signs. This demands the development of new automated ECNDT tools, and this article offers a promising avenue for improvement. The results include model and experimental tests of system components, showcasing the potential of this approach to enhance ECNDT effectiveness, automation, and informativeness in the realm of aircraft part diagnostics.

3

Definition of sampled signal spectrum and shannon’s proof of reconstruction formula

Borys A.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2022

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Vol. 16 No. 3

473--478

EN

The objective of this paper is to show from another perspective that the definition of the spectrum of a sampled signal, which is used at present by researchers and engineers, is nothing else than an arbitrary choice for what is possibly not uniquely definable. To this end and for illustration, the Shannon’s proof of reconstruction formula is used. As we know, an auxiliary mathematical entity is constructed in this proof by performing periodization of the spectrum of an analog, bandlimited, energy signal. Admittedly, this entity is not called there a spectrum of the sampled signal - there is simply no need for this in the proof – but as such it is used in signal processing. And, it is not clear why just this auxiliary mathematical object has been chosen in signal processing to play a role of a definition of the spectrum of a sampled signal. We show here what are the interpretation inconsistences associated with the above choice. Finally, we propose another, simpler and more useful definition of the spectrum of a sampled signal, for the cases where it can be needed.

4

Advanced Signal Processing Methods for Inspection of Aircraft Structural Materials

Lysenko Iuliia, Eremenko Volodymyr, Kuts Yurii, Protasov Anatoliy, Uchanin Valentin

Transactions on Aerospace Research

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2020

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Nr 2 (259)

27--35

EN

Aircraft, their assemblies, and units must provide high durability and reliability, and maintain mechanical and technological characteristics throughout the life span of the aircraft. Different elements of aircraft structures work under mechanical loads, over a wide temperature range, with varying degrees of exposure to corrosive environments. Aircraft structural materials have a variation in the characteristics values and require the various testing methods for their inspection. In many NDT methods applied in aviation materials testing, signals that could be represented by a narrowband processes model are used. Known methods of their processing are focused on determining and analyzing the signals amplitude characteristics, but the information resource contained in phase characteristics is not used. In the article, the methodology for signal processing and determining phase characteristics in the time domain are discussed. It is based on the combination of the discrete Hilbert transform and the deterministic and statistical methods of the phase measurement. There are given examples of the application of the methodology for pulsed eddy current testing of electrically conductive materials and products, ultrasonic thickness measurement of products made of materials have significant ultrasonic attenuation, the realization impulse variant of acoustic impedance flaw detection of products made of composite materials. The examples have shown that the proposed signal processing methodology enables to determine new information parameters and signal characteristics for the industry, and extend the scope of known NDT methods.

PL

Samoloty, ich zespoły i jednostki muszą zapewniać wysoką trwałość i niezawodność oraz utrzymywać właściwości mechaniczne i technologiczne przez cały okres użytkowania statku powietrznego. Różne elementy konstrukcji lotniczych pracują pod obciążeniami mechanicznymi, w szerokim zakresie temperatur, z różnym stopniem narażenia na środowiska korozyjne. Materiały konstrukcyjne statków powietrznych różnią się właściwościami i wymagają różnych metod testowania w celu ich kontroli. W wielu metodach NDT stosowanych w testowaniu materiałów lotniczych sygnały, które mogą być badane stosowany jest model procesów wąskopasmowych. Znane metody ich przetwarzania koncentrują się na określeniu i analizie charakterystyk amplitudy sygnałów, ale zasoby informacyjne zawarte w charakterystyce fazowej nie są wykorzystywane. W artykule omówiono metodologię przetwarzania sygnału i określania charakterystyk fazowych w domenie czasowej. Opiera się on na kombinacji dyskretnej transformaty Hilberta oraz deterministycznych i statystycznych metod pomiaru fazy. W pracy podano przykłady zastosowania metodyki badań pulsacyjnych prądów wirowych materiałów i produktów przewodzących prąd. Ultradźwiękowy pomiar grubości wyrobów wykonanych z materiałów ma znaczne tłumienie ultradźwięków, wariant realizacji defektu impedancji akustycznej wykrywania wad wykonanych z materiałów kompozytowych. Przykłady pokazały, że proponowana metodologia przetwarzania sygnału umożliwia określenie nowych parametrów informacji i charakterystyk sygnału dla materiałów oraz rozszerza zakres znanych metod NDT.