Wyniki wyszukiwania - BazTech

1

Wykorzystanie urządzeń mobilnych do akwizycji i przetwarzania sygnałów biomedycznych w czasie rzeczywistym

Harasimczuk Adrian, Sieczkowski Krzysztof

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2025

|

nr 1

21--27

PL

W artykule opisano projekt aplikacji mobilnej, dedykowanej dla urządzenia typu smartphone pracującego pod kontrolą systemu operacyjnego Android, przeznaczonej do akwizycji sygnałów biomedycznych. Wybranym sygnałem biomedycznym stosowanym w niniejszej pracy był sygnał PPG (ang. Photoplethysmogram), pozyskany z dedykowanego układu. Dane zbierane są przy pomocy modułu ESP 32 z podłączonym sensorem typu MA X30102. Następnie przesyłane są w czasie rzeczywistym do urządzenia mobilnego za pośrednictwem sieci Bluetooth Low Energy. Do przetwarzania danych biomedycznych wykorzystano procesy filtrowania sygnału, detekcji wartości szczytowych, wyliczania pulsu i saturacji. Użytkownik ma możliwość obserwacji wyników w czasie rzeczywistym na dedykowanych wykresach. Wykonane badania testowe potwierdzają poprawność działania aplikacji oraz zawierają porównanie efektów pracy z pomiarami wykonanymi za pomocą urządzeń komercyjnych typu pulsoksymetr i smartwatch.

EN

This paper describes the design of a mobile application for a smartphone device running the Android operating system with the intent of acquiring biomedical signals. The selected biomedical signal used in this work was the Photoplethysmogram (PPG ) signal, acquired via a dedicated Analog Front-End (AFE) chip. The data is collected using an ESP 32 module with a MA X30102 type AFE sensor connected. It is then transmitted in real time to a mobile device via Bluetooth Low Energy. Signal filtering, peak detection, as well as pulse and saturation calculation processes were used to process the biomedical data. The user can observe the results in real time on dedicated graphs. Conducted test studies confirm that the application functions correctly and include a comparison of the results with measurements made with commercial devices such as pulse oximeter and smartwatch.

2

Improve the safety of air transport, especially in militarized terrain, by use of side looking airborne radar and space time adaptive processing

Ślesicki Błażej, Ślesicka Anna, Kawalec Adam

Zeszyty Naukowe. Transport / Politechnika Śląska

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2024

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z. 123

335--346

EN

The paper explores the potential to enhance aviation safety, particularly in militarized regions, by outfitting aircraft with Side Looking Airborne Radar (SLAR) and employing space-time adaptive processing (STAP) algorithms. The research objective revolves around implementing a model of side-looking airborne radar and the corresponding STAP algorithms. This technology enables the detection of slow-moving targets amidst strong interference, encompassing both passive (clutter) and active (jammer) elements. Slow-moving targets relative to the aircraft's speed include tanks, combat vehicles, command vehicles, artillery, and logistical assets of enemy forces. The theoretical framework of space-time adaptive processing is presented, elucidating the sequential steps of the classical Sample Matrix Inversion Space-Time Adaptive Processing (SMI STAP) algorithm. The paper underscores the significance of characteristic parameters delineating a linear STAP processor. The proposed solution facilitates the detection of enemy combat measures and enhances aviation safety. It outlines a radar model installed beneath the aircraft's fuselage and elucidates algorithms for space-time adaptive processing of radar signals. The simulations conducted within the article were executed using the MATLAB environment. The simulation results indeed suggest that the proposed solution holds promise for deployment in equipping aircraft of one's own military and those engaged in operations within conflict zones. This paper stands as one of the few contributions in the literature addressing the augmentation of aircraft safety through radar and space-time adaptive processing.

3

Klasyfikacja sygnałów EEG w interfejsach mózg-komputer z wykorzystaniem sieci neuronowych

Galas Krzysztof

Studia i Materiały Informatyki Stosowanej

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2024

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T. 16, nr 3

18--23

PL

Celem pracy jest zaprezentowanie metod klasyfikacji sygnałów EEG w interfejsach mózg-komputer (BCI) z wykorzystaniem sieci neuronowych. Dzięki ich zdolności do modelowania złożonych zależności w danych, możliwe jest skuteczniejsze rozpoznawanie wzorców aktywności mózgowej, co przyczynia się do poprawy dokładności i szybkości działania systemów BCI. W pracy omówiono architektury sieci neuronowych wykorzystywane do analizy sygnałów EEG, takie jak sieci konwolucyjne (CNN) czy rekurencyjne (RNN). Badania pokazują, że te metody mają ogromny potencjał w zastosowaniach takich jak sterowanie urządzeniami wspomagającymi, komunikacja oraz rozrywka.

EN

The aim of this paper is to present methods for classifying EEG signals in brain-computer interfaces (BCIs) using neural networks. Thanks to their ability to model complex relationships in the data, it is possible to recognise patterns of brain activity more effectively, which contributes to improving the accuracy and speed of BCI systems. This paper discusses neural network architectures used to analyse EEG signals, such as convolutional networks (CNNs) or recurrent networks (RNNs). The research shows that these methods have immense potentialin applications such as assistive device control, communication,and entertainment.

4

Electronic system and signal processing in torque-meter interface of switched reluctance motor drive laboratory test bench

Fabiański Bogdan, Pajchrowski Tomasz, Zawirski Krzysztof

Przegląd Elektrotechniczny

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2024

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R. 100, nr 11

59--66

EN

The article aims to present – from a functional point of view – the key solutions of an automated laboratory stand for testing a switched reluctance motor drive. Particular emphasis was placed on one of the proprietary modules of this stand: the dedicated interface of the FUTEK TRS705 torque meter. In this respect, the physical layer and the most important algorithms are discussed. The concept of building a research test bench that will be able to collect information about the basic relationships of a given specimen in an automated and – at the same time – in precise manner is important since fundamental phenomena: generation of electromagnetic torque and an electromotive force are characterized by significant nonlinearities that must be taken into account in the motor models. Hence the issues presented in the article (precise, open torque meter interface) can be considered and useful in a much broader (generic) context, constituting a contribution to solutions in electric drive. The presented methods and system solutions were verified experimentally along with the final presentation of the results of the station operation.

PL

Artykuł ma na celu przedstawienie -- z funkcjonalnego punktu widzenia -- kluczowych rozwiązań zautomatyzowanego stanowiska laboratoryjnego do badania silnika reluktancyjnego przełączalnego. Szczególny nacisk położono na jeden z autorskich modułów tego stanowiska tj. dedykowany interfejs momentomierza przelotowego marki FUTEK TRS705. W tym zakresie omówiono warstwę fizyczną, jak i najważniejsze algorytmy zaimplementowane w programie systemu wbudowanego. Koncepcja opisywanej budowy stanowiska badawczego, które w sposób zautomatyzowany i zarazem precyzyjny będzie mogło zebrać informacje o podstawowych relacjach danego egzemplarza silnika jest bardzo istotna z perspektywy rozwoju algorytmów sterowania -- w szczególności tych wykorzystujących model referencyjny. Fundamentalne zjawiska: generowania momentu elektromagnetycznego oraz wytwarzania siły elektromotorycznej charakteryzują się w silniku SRM istotnymi nieliniowościami, które powinny być uwzględnione w jego modelach obwodowych. Stąd, przedstawione w artykule zagadnienia mogą być rozpatrywane i użyteczne w znacznie szerszym kontekście. Co istotne, przedstawione metody i rozwiązania układowe zweryfikowano eksperymentalnie wraz z końcowym przedstawieniem rezultatów działania stanowiska.

5

Research on vibration-based early diagnostic system for excavator motor bearing using 1-D CNN

Yandagsuren Dorjsuren, Kurauchi Tatsuki, Toriya Hisatoshi, Ikeda Hajime, Adachi Tsuyoshi, Kawamura Youhei

Journal of Sustainable Mining

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2023

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Vol. 22, iss. 1

65--80

EN

In mining, super-large machines such as rope excavators are used to perform the main mining operations. A rope excavator is equipped with motors that drive mechanisms. Motors are easily damaged as a result of harsh mining conditions. Bearings are important parts in a motor; bearing failure accounts for approximately half of all motor failures. Failure reduces work efficiency and increases maintenance costs. In practice, reactive, preventive, and predictive maintenance are used to minimize failures. Predictive maintenance can prevent failures and is more effective than other maintenance. For effective predictive maintenance, a good diagnosis is required to accurately determine motor-bearing health. In this study, vibration-based diagnosis and a one-dimensional convolutional neural network (1-D CNN) were used to evaluate bearing deterioration levels. The system allows for early diagnosis of bearing failures. Normal and failure-bearing vibrations were measured. Spectral and wavelet analyses were performed to determine the normal and failure vibration features. The measured signals were used to generate new data to represent bearing deterioration in increments of 10%. A reliable diagnosis system was proposed. The proposed system could determine bearing health deterioration at eleven levels with considerable accuracy. Moreover, a new data mixing method was applied.

6

Challenges in assessing the vibrations influence on people in buildings using non-contact measurements

Bróż Natalia, Nazarko Piotr

Czasopismo Inżynierii Lądowej, Środowiska i Architektury / Journal of Civil Engineering, Environment and Architecture

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2023

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Vol. 70

51--64

EN

This research article presents a comparative analysis of vibration assessments in lecture halls to investigate their influence on people using contact (accelerometers) and non-contact (laser vibrometers) measurement techniques. The study aims to verify the accuracy and reliability of vibration analysis in relation to two approaches and determined physical parameters, i.e. acceleration amplitudes and vibration velocities. The intriguing fact was that none of the building users reported any perceived discomfort from vibrations, despite the determined parameters of the signal measured using a laser vibrometer indicating exceedance of permissible vibration amplitudes in several frequency bands. The conducted comparative analysis leads to the conclusion that the location of the laser head tripod on the vibrating floor introduces significant vibration amplification, which in turn may lead to an incorrect assessment of the impact of vibrations on people in buildings. The studies described in the article were carried out in accordance with the procedure contained in the Polish national standard PN-B-02171. The obtained results and the resulting conclusions are an important contribution to a better understanding of the advantages and limitations resulting from the use of non-contact measurements.

7

The concept of disrupting anti-radiation missiles in a radar decoy

Ślesicka Anna, Ślesicki Błażej

Aviation and Security Issues

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2023

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No. 1

167--181

EN

The ongoing armed conflicts in the world today demonstrate the huge role of electronic reconnaissance, which is becoming one of the primary sources of data on the enemy and the area of operations. One of the tools of radioelectronic warfare, which includes electronic reconnaissance, are radiolocation stations, which play a key role in detecting, tracking and identifying enemy aircraft and in directing armaments to combat these threats. The enemy’s own radiolocation stations are also targeted. The missiles used to do this are called anti-radar missiles (ARM). One way to defend against them is to modify the electromagnetic field around the protected radar. The purpose of this article was to present a model of coherent interference of an anti-radiation missile in a radar trap system The authors applied an analysis of the available literature and carried out computer simulations in the MATLAB environment. In conclusion, the important role played by radar decoys on today’s battlefield was pointed out.

PL

Toczące się obecnie na świecie konflikty zbrojne dowodzą ogromnej roli rozpoznania elektronicznego, które staje się jednym z podstawowych źródeł danych na temat przeciwnika i obszaru działań. Jednym z narzędzi walki radioelektronicznej, w której skład wchodzi rozpoznanie elektroniczne, są stacje radiolokacyjne, pełniące kluczową rolę w wykrywaniu, śledzeniu i identyfikacji przeciwników latających oraz w kierowaniu uzbrojeniem w celu zwalczania tych zagrożeń. Własne stacje radiolokacyjne są również celem przeciwnika. Pociski, które do tego służą, nazywa się pociskami przeciwradiolokacyjnymi. Jednym ze sposobów obrony jest modyfikacja pola elektromagnetycznego w otoczeniu chronionego radaru. Celem artykułu było przedstawienie modelu koherentnego zakłócenia pocisku przeciwradiolokacyjnego w systemie pułapek radiolokacyjnych radaru. Autorzy zastosowali analizę dostępnej literatury oraz przeprowadzili symulacje komputerowe w środowisku Matlab. Podsumowując, wskazano na istotną rolę, jaką pełnią na dzisiejszym polu walki pułapki radiolokacyjne.

8

Detection and diagnosis of bearing defects using vibration signal processing

Bouaouiche Karim, Menasria Yamina, Khalfa Dalila

Archive of Mechanical Engineering

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2023

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LXX, nr 3

433--452

EN

This work presents an analysis of vibration signals for bearing defects using a proposed approach that includes several methods of signal processing. The goal of the approach is to efficiently divide the signal into two distinct components: a meticulously organized segment that contains relatively straightforward information, and an inherently disorganized segment that contains a wealth of intricately complex data. The separation of the two component is achieved by utilizing the weighted entropy index (WEI) and the SVMD algorithm. Information about the defects was extracted from the envelope spectrum of the ordered and disordered parts of the vibration signal. Upon applying the proposed approach to the bearing fault signals available in the Paderborn university database, a high amplitude peak can be observed in the outer ring fault frequency (45.9 Hz). Likewise, for the signals available in XJTU-SY, a peak is observed at the fault frequency (108.6 Hz).

9

Funkcjonalizacja materiałów elektrodowych dla woltamperometrii związków organicznych z elementami standaryzacji i przetwarzania sygnałów

Porada Radosław, Kochana Jolanta, Baś Bogusław

Analityka : nauka i praktyka

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2023

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nr 3

16--23

PL

Artykuł opracowany na podstawie rozprawy doktorskiej dr. Radosława Porady pt.: Funkcjonalizacja materiałów elektrodowych dla woltamperometrii związków organicznych z elementami standaryzacji i przetwarzania sygnałów nagrodzonej przez Komitet chemii Analitycznej PAN w 2023 roku w konkursie na najlepsze prace doktorskie. Nagroda ufundowana przez firmę nLab.

10

Budowa liczników energii elektrycznej prądu przemiennego

Makles Piotr

Wiadomości Elektrotechniczne

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2022

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R. 90, nr 4

21--28

PL

W artykule przedstawiono rozwiązania konstrukcyjne stosowane w nowoczesnych, elektronicznych licznikach energii elektrycznej. Opisana została budowa podstawowych układów elektronicznych, ze szczególnym uwzględnieniem obwodów pomiarowych wpływających na dokładność oraz możliwości pomiarowe liczników. Zaprezentowane zostały również najważniejsze wymagania norm dotyczące niezawodności oraz bezpieczeństwa urządzeń.

EN

This article presents information about electricity meters construction. Measurement circuits of meters and informations about different circuits solutions accuracy has been presented. The most important requirements of standards regarding the safety and accuracy of electricity meters were also described.

11

Leaky partial updates to control a real device casing

Bismor Dariusz

Vibrations in Physical Systems

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2022

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Vol. 33, nr 3

art. no. 2022304

EN

Structural active noise control (ANC) is one of few solutions applicable when global noise reduction is required: control of a whole device casing allows to lower the acoustic energy emitted by this device. Unfortunately, structural ANC usually requires a large number of sensors and actuators, making the control system multichannel with large dimensionality. This in turn presents a huge computational power demands. There are several ways to lower this demand, the partial updates being one of them. The goal of this paper is to show applicability of the leaky partial update LMS algorithms in structural ANC of a washing machine casing. The transfer functions of the numerous device paths were identified using a real washing machine in the ANC laboratory. The identified transfer functions allowed to create a simulation system, where different algorithms could be easily tested. The results of the simulations confirm effectiveness of the proposed solution.

12

Enhancing speech signals based on an mems microphone array and temporal differences in the incoming signal

Felcyn Jan, Raszewski Michał

Vibrations in Physical Systems

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2022

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Vol. 33, nr 2

art. no. 2022202

EN

The development of the Internet of things and automatisation in everyday life also influences our houses. There are more and more devices on the market which can be controlled remotely. One kind of such control involves the use of voice signals. This method tends to use microphone arrays and dedicated algorithms to enhance the speech signal and recognize the words in it. In this project, a small 5-microphone array was developed. To enhance the quality of the signal, dedicated software was written. It consists of several modules, including the direction of arrival estimation, denoising, and differentiation between adults and children. The results showed that the custom algorithm can increase the signal to noise ratio by up to 6 dB.

13

Effect of changing body position on selected voice parameters

Węglarz Karolina, Wszołek Wiesław, Hemmerling Daria

Vibrations in Physical Systems

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2022

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Vol. 33, nr 3

art. no. 2022320

EN

Correct posture is a key element in the proper functioning of the entire body. Both defects and postural disorders lead to overload syndromes and degenerative changes in the musculoskeletal system. Different body positions correlate with respiratory parameters, which form the basis in modifying loudness and accentuation when speaking or singing Body posture can affect the quality of the voice signal and its fatigue. As movement and duration intensify, vocal effort increases. What is still open, however, is the problem of speech signal evaluation, especially in order to obtain assessments useful in the context of supporting medical diagnosis, optimizing therapy and monitoring rehabilitation. Meanwhile, such evaluations are what we need in medicine, rehabilitation and sports. This paper presents excerpts from a study of the effects of changes in posture and fatigue in healthy subjects, and those with phonation disorders, on changes in the acoustic parameters of the speech signal.

14

Application of the discrete linear chirp transform (DLCT) to estimate the parameters of multicomponent LFM signals

Fiołka Jerzy

Przegląd Elektrotechniczny

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2022

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R. 98, nr 6

45--49

EN

This paper is focused on method to estimate the parameters of multicomponent linear frequency modulation (LFM) signals. These nonstationary signals, which are often referred to as ”chirp”, are encountered in many fields such as communication, vibration analysis, radar systems. The presented method, which is based on the discrete linear chirp transform (DLCT), permits the chirp parameters to be precisely estimated. Its high performance, which was proven by the simulation results, coupled with its simplicity, makes this method useful for many applications.

PL

W artykule przedstawiono metodę estymacji parametrów wieloskładnikowych sygnałów z liniową modulacją częstotliwości. Z tego typu sygnałami mamy do czynienia w takich dziedzinach jak telekomunikacja, analiza drgań, systemy radarowe. Przedstawiona metoda, bazująca na DLCT (ang. Discrete linear chirp transform), pozwala na oszacowanie parametrów wspomnianych sygnałów. Jej wysoka skuteczność, potwierdzona wynikami symulacji, w połączeniu z prostotą, czyni metodę użyteczną w wielu zastosowaniach.

15

Przetwarzanie sygnałów : nasz wkład w cyfrowy świat

Kulpa Krzysztof, Świercz Mirosław, Dąbrowski Adam, Samczyński Piotr, Augustyniak Piotr

Elektronika : konstrukcje, technologie, zastosowania

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2022

|

Vol. 63, Nr 11

35--38

PL

Artykuł prezentuje historię i najważniejsze dokonania Oddziału Signal Processing Society Polskiej Sekcji IEEE oczami jego założyciela i kolejnych przewodniczących. Uwagę zwraca zarówno wszechstronność zastosowań przetwarzania sygnałów we współczesnej technice, członkostwo w Oddziale przedstawicieli najważniejszych ośrodków w Polsce oraz mnogość inicjatyw podejmowanych wspólnie w ramach Oddziału i adaptacja ich form do potrzeb środowiska branżowego.

EN

The article presents the history and the most important achievements of the Signal Processing Society Chapter of the IEEE Polish Section through the eyes of its founder and subsequent chairmen. Attention is drawn to the versatility of signal processing applications in modern technology, the membership of the representatives of the most important centers in Poland in the Chapter, and the multitude of initiatives undertaken jointly within the Chapter and the adaptation of their forms to the needs of the society of professionals.

16

Fault diagnosis of induction motors rotor using current signature with different signal processing techniques

Guezam Abdelhak, Bessedik Sid Ahmed, Djekidel Rabah

Diagnostyka

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2022

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Vol. 23, No. 2

art. no. 2022201

EN

The popularity of asynchronous machines, particularly squirrel cage machines, stems from their inexpensive production costs, resilience, and low maintenance requirements. Unfortunately, potential flaws in these devices might have a negative impact on the facility's profitability and service quality. As a result, diagnostic tools for detecting flaws in these types of devices must be developed. Asynchronous machine problems can be diagnosed using a variety of methods. Signal processing techniques based on extracting information from characteristic quantities of electrical machine operation can provide highly useful information about flaws. The purpose of this research is to develop efficient algorithms based on numerous signal processing approaches for correctly detecting asynchronous cage machine rotor defects (rotor bar ruptures).

17

Zastosowanie wielosensorowego systemu pomiarowego do monitorowania procesu skrawania – przypadek sekwencyjnych procesów toczenia i nagniatania

Bartoszuk Marian, Grzesik Wit, Chudy Roman

Mechanik

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2021

|

R. 94, nr 1

6--12

EN

In this paper, the structure and operational functions of a measurement system, which was installed on a 3-axis CNC lathe for monitoring and optimization of the cutting process are presented. In general, the system records signals of the components of the resultant cutting force, acceleration signals (cutting vibrations) and EFM force signals generated for various machining conditions employed. As a result, the total power consumed was determined. The generated data were archived in the expert system which supports the optimization of the cutting process in terms of various optimization criteria including power/energy consumption.

PL

W artykule przedstawiono budowę i funkcje eksploatacyjne układu pomiarowego, który został zainstalowany na 3-osiowej tokarce CNC w celu monitorowania i optymalizacji procesu skrawania. System rejestruje sygnały składowych wypadkowej siły skrawania, sygnały przyspieszenia (drgania skrawania) oraz sygnały siły EFM generowane dla różnych zastosowanych warunków obróbki. W rezultacie określono całkowitą pobieraną moc. Wygenerowane dane zostały zarchiwizowane w systemie ekspertowym, który wspiera optymalizację procesu cięcia pod kątem różnych kryteriów optymalizacji, w tym poboru mocy / energii.

18

Diagnosis of air compressor condition using minimum redunduncy maximum relevance (MRMR) algorithim and distance metric based classification

Al-Bugharbee Hussein, Samaka Hatem, Zubaidi Salah L.

Diagnostyka

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2021

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Vol. 22, No. 4

25--32

EN

Finding a reliable machines condition monitoring technique has been attracted many researchers to avoid the sudden failure in machines and the unexpected consequences. This work proposes a fault diagnosis of air compressors using frequency-based features and distance metric-based classification. The analyzed experimental datasets contain one healthy condition and seven different fault conditions. Features are extracted from the frequency spectrum, then the best feature sets are selected using MRMR algorithm and eventually the classification is conducted using a distance metric classifier. The results demonstrated the automatic classification with more than 97% correct classification rate. The effect of selected feature set size, training sample size on the classification accuracy is also investigated. From the results, this method of analysis can be used for early detection of faults with very great accuracy.

19

Using BCI and EEG to process and analyze driver’s brain activity signals during VR simulation

Nader Mirosław, Jacyna-Gołda Ilona, Nader Stanisław, Nehring Karol

Archives of Transport

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2021

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Vol. 60, iss. 4

137--153

EN

The use of popular brain–computer interfaces (BCI) to analyze signals and the behavior of brain activity is a very current problem that is often undertaken in various aspects by many researchers. This comparison turns out to be particularly useful when studying the flows of information and signals in the human-machine-environment system, especially in the field of transportation sciences. This article presents the results of a pilot study of driver behavior with the use of a pro-prietary simulator based on Virtual Reality technology. The study uses the technology of studying signals emitted by the human mind and its specific zones in response to given environmental factors. A solution based on virtual reality with the limitation of external stimuli emitted by the real world was proposed, and computational analysis of the obtained data was performed. The research focused on traffic situations and how they affect the subject. The test was attended by representatives of various age groups, both with and without a driving license. This study presents an original functional model of a research stand in VR technology that we designed and built. Testing in VR conditions allows to limit the influence of undesirable external stimuli that may distort the results of readings. At the same time, it increases the range of road events that can be simulated without generating any risk for the participant. In the presented studies, the BCI was used to assess the driver's behavior, which allows for the activity of selected brain waves of the examined person to be registered. Electro-encephalogram (EEG) was used to study the activity of brain and its response to stimuli coming from the Virtual Reality created environment. Electrical activity detection is possible thanks to the use of electrodes placed on the skin in selected areas of the skull. The structure of the proprietary test-stand for signal and information flow simulation tests, which allows for the selection of measured signals and the method of parameter recording, is presented. An important part of this study is the presentation of the results of pilot studies obtained in the course of real research on the behavior of a car driver.

20

Vibroacoustic condition monitoring of the complex rotation system based on multilevel signal processing

Pazdrii Olha, Bouraou Nadiia

Vibrations in Physical Systems

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2020

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Vol. 31, nr 2

art. no. 2020224

EN

This work is devoted to further research and improvement of the vibroacoustic condition monitoring of complex rotation system during operation. The low-frequency vibration and acoustic noise in the range 0-10 kHz is used as diagnostic information. We propose to use Bispectrum (BS) Analysis at the first level of signal processing, and Fractal Analysis of BS contour images at the second level of signal processing for the diagnosis of small imbalance of rotation system. The experimental studies of forced vibrations of the physical model (PM) of the rotation system are carried out under steady-state and non-steady-state rotation excitations. The results of the BS Analysis of vibroacoustical signals, which are emitted by a rotating PM during different excitation modes, are processed in order to determine fractal box-counting dimension (Minkowski dimension). The research shows that a small imbalance can be efficiently detected by the proposed multilevel signal processing in all modes of PM operation.