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1

Wavelet analysis of the EMG signal to assess muscle fatigue in the lower extremities during symmetric movement on a rowing ergometer

Daniel Natalia, Małachowski Jerzy

Acta of Bioengineering and Biomechanics

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2023

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Vol. 25, no. 2

15--27

EN

The aim of this publication was to propose a method to determine changes in fatigue in selected muscle groups of the lower extremity during dynamic and cyclical motion performed on a rowing ergometer. The study aimed to use the discrete wavelet transform (DWT) to analyze electromyographic signals (EMG) recorded during diagnostic assessment of muscle and peripheral nerve electrical activity (electroneurography) using an electromyography device (EMG). Methods: The analysis involved implementing calculations such as mean frequency (MNF) and median frequency (MDF) using the reconstructed EMG signal through DWT. The study examined the efficacy of DWT analysis in assessing muscle fatigue after physical exertion. Results: The study obtained a negative regression coefficient for DWT analysis in all muscles except for the right gastrocnemius (GAS). The results suggest that DWT analysis can be an effective tool for evaluating muscle fatigue after physical exertion. Conclusions: The use of DWT in the analysis of EMG signals during rowing ergometer exercises has shown promising results in assessing muscle fatigue. However, additional investigations are necessary to confirm and expand these findings. This publication addresses the literature gap on the determination of muscle fatigue considering motion analysis on a rowing ergometer using the discrete wavelet transform. Previous studies have extensively compared and analyzed methods such as the Fourier transform (FFT), short-time Fourier transform (STFT), and wavelet transform (WT) for muscle fatigue analysis. However, no previous work has specifically examined the assessment of muscle fatigue by incorporating DWT analysis with motion analysis on a rowing ergometer.

2

Analysis of muscle activity during rowing stroke phases

Czajkowska Urszula, Świątek-Najwer Ewelina, Jankowski Ludomir

Acta of Bioengineering and Biomechanics

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2023

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Vol. 25, no. 1

117--126

EN

Rowing engages large muscle groups and electromyography (EMG) analysis is used to assess athletes’ condition and refine sports technique. The aim of the experiment was to evaluate the muscle activation level during different phases of the rowing cycle on an ergometer. Methods: In a study involving one professional and five amateurs, the mean EMG amplitudes from the quadriceps, gastrocnemius, biceps and triceps brachii were analyzed during different phases of rowing. A comparison was made between the degree of muscle engagement during the exercise between the professional and inexperienced individuals as well as among the different individuals during recordings obtained at different rowing speeds. The correlation coefficient between the values recorded using a strain gauge and the EMG amplitude recorded from the surface of the biceps and triceps brachii muscles was evaluated. Results: The muscle activation pattern during rowing has a predictable character. A difference in the muscle activation pattern during rowing between the professionals and amateurs was observed. The EMG signal is correlated with the force recorded by the resistive strain gauge only in the experienced rower at stroke rates 20 and 25 [1/min]. Conclusions: Electromyographic analysis can be useful for assessing the correctness of rowing techniques. The activation pattern of muscles during rowing has a predictable nature. The force generated by the participants increases with an increase in rowing frequency.

3

Influence of a hybrid manual - electric wheelchair propulsion system on the user's muscular effort

Wieczorek Bartosz, Warguła Łukasz, Kukla Mateusz

Acta Mechanica et Automatica

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2023

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Vol. 17, no. 1

28--34

EN

Self-propelled wheelchairs favour the rehabilitation process, forcing the user to be physically active. Unfortunately, in most cases, the manual propulsion is not adapted to the individual needs and physical capabilities of the user. This paper presents the results of operational tests of a wheelchair equipped with a hybrid propulsion system in which the muscle strength generated by the user is assisted by two independent electric motors. The research aimed to investigate the influence of the applied control algorithm and the assistance factor (W) on the value of the muscular effort (MA) while propelling the wheelchair with the use of push rims. A modified ARmedical AR-405 wheelchair equipped with two MagicPie 5 electric motors built into the wheelchair’s hubs with a power of 500 W was used in this research. The tests were carried out on a wheelchair test bench simulating the moment of resistance within the range of 8–11 Nm. Surface electromyography was employed for the measurement of MA, specifically, a four-channel Noraxon Mini DTS apparatus. The research was carried out on five patients from the group of C50 anthropometric dimensions. The effort was measured for four muscles: deltoid–anterior part, deltoid–posteriori part, and triceps brachii and extensor carpi radialis longus. The effectiveness of the hybrid propulsion system was observed based on the extensor carpi radialis longus muscle. In this case, for the standard wheelchair, the MA ranged from 93% to 123%. In contrast, for a wheelchair equipped with the hybrid propulsion system, at W = 70%, the MA was within the range of 43%–75%.

4

Identification of muscle movements and activity by experimental methods for selected cases – stage#1

Dejneka Aleksandra, Małachowski Jerzy, Mazurkiewicz Łukasz

Acta of Bioengineering and Biomechanics

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2022

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Vol. 24, no. 3

69--82

EN

The aim of this study was to determine the position where the most activated and isolated individual muscles were. In the next steps, the selected limb positions will be used to determine the maximum values of isometric forces of the individual muscle heads based on the Hill model. Methods: In order to determine the sought muscle activation, an electromyograph was used. Isometric contraction measurements were carried out for seven series of tests. Isometric contraction was performed as 100% MVC. Results: For the long head of the biceps muscle, in the case of bending in the shoulder joint, angle of 75° was selected and for abduction in the shoulder joint – 90°. Internal rotation in the shoulder joint was omitted because of lower activation values. For the short head of the biceps muscle, the angle characterized by the greatest activity of the head was the angle of 115° in flexion at the elbow joint. The selected angle was 30° for shoulder extension and 110° for shoulder adduction. For the lateral head of the triceps brachial muscle, measurements showed that the angle at which the lateral head was most activated is 115°. Conclusions: The aim of this study was to determine the positions of the arm muscles that activate and isolate individual heads the most. The research presented and achieved results concern one specific person for whom a personalized numerical model was developed to represent the flexion-extension movement at the elbow joint. The performed tests can also be a preliminary assessment of the upper limb positions, for which wider conclusions could be drawn in the case of measurements on a larger number of participants.

5

Identification of muscle movements and activity by experimental methods for selected cases – stage #2

Dejneka Aleksandra, Małachowski Jerzy, Mazurkiewicz Łukasz

Acta of Bioengineering and Biomechanics

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2022

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Vol. 24, no. 4

3--11

EN

The aim of the performed tests and static measurements was to determine the torque and to determine the activity curve for individual muscle heads during the flexion-extension movement in the elbow joint. Methods: Both heads of the biceps branchial muscle and the triceps muscle of the arm – long head and lateral head – were examined. Static measurements were carried out for four selected positions of the upper limb. For each pose, a measurement series consisting of five attempts of ten seconds of effort was performed. Isometric contraction was performed as 100% of the maximum voluntary MVC contraction. Dynamic measurements were carried out when working in isokinetic conditions. In both stages, an EMG and a Biodex isokinetic dynamometer were used. Results: During the analyses, it was assumed that the average value of the torque is equal to the approximate value of the torque of a given head under static conditions. The value of the torque of the biceps brachial muscle, long head was 48.04 Nm and for the short head – 45.82 Nm. For the triceps muscle of the long head, this value was 52.52 Nm and for the lateral head – 38.06 Nm. On the basis of dynamic measurements, four activation curves were determined for each of the heads during the 7-second task. For the curves, the sum value of muscle activity in a given period of time was calculated as the area under the curve. Conclusions: Both parts of the series of articles present a series of experimental studies conducted in order to determine the parameters for one patient, for whom a personalized numerical model of the upper limb was ultimately created. Static measurements were carried out to determine the maximum values of the moments of forces. Dynamic measurements allowed for the determination of activity curves during the movement of the upper limb.

6

Electromyographic assessment of muscle fatigue after the Biering–Sorensen test in subjects with low back pain who underwent the McKenzie treatment

Jabłońska Magdalena, Mączyński Jacek, Fryzowicz Anna, Ogurkowska Małgorzata B.

Acta of Bioengineering and Biomechanics

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2021

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Vol. 23, no. 3

87--96

EN

Purpose: Chronic low back pain is a common disorder affecting about 80% of the population, caused by a disorder in the muscular system. The main aim of this study was to assess muscle fatigue during the Biering–Sorensen Test in people with chronic low back pain who underwent the McKenzie treatment. Methods: Tests were conducted on 19 men (mean age of 41.4 years) with chronic non-specific lumbar-sacral pain syndrome, working in the seated position in front of a computer. Assessment of changes in fatigue of erector spinae, gluteus maximus and biceps femoris using surface electromyography during the Biering–Sorensen Test and subjective pain assessment using Visual Analog Scale were conducted on three test dates. Time-frequency representation of the electromyographic signal (Fourier transform) was used for the examination of muscle fatigue. The McKenzie method of diagnosis and therapy was applied before and between the tests. Results: The McKenzie therapy resulted in increased endurance (test duration) of the examined spinal muscles between the 1st and 3rd test date (p = 0.043), and a systematic decrease in pain assessment on the three test dates (p = 0.000–0.004). Correlations were obtained between slope coefficients of the simple regression of median frequency of electromyographic signals on the one hand and duration of the BST (p = 0.000–0.012) and anthropometric parameters (body mass, height and body mass index, p = 0.001–0.020) on the other. Conclusions: The McKenzie method is an effective tool in reducing the level of lumbar pain and improving muscle endurance.

7

General concept of the EMG controlled bionic hand

Pieprzycki Adam, Król Daniel

Science, Technology and Innovation

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2020

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Vol. 8, no. 1

26--34

EN

The article presents a general concept of a bionic hand control system using multichannel EMG signal, being under development at present. The method of acquisition and processing of multi-channel EMG signal and feature extraction for machine learning were described. Moreover, the design of the control system implementation in the real-time embedded system was discussed.

8

A Comparison of Methods of Controlling the Movement of an Exoskeleton, Supporting Movements of the Upper Limb Using Signals of Muscle Activity and Manual Controls

Jankowski Jarosław, Łach Patrycja

Problemy Mechatroniki : uzbrojenie, lotnictwo, inżynieria bezpieczeństwa

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2020

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Vol. 11, Nr 3 (41)

19--32

EN

The paper presents the research methodology and the analysis of the results of the comparison test of two methods of controlling the exoskeleton of the upper limb using signals of muscle activity and manual control devices. The results show the advantage of the joystick method over EMG in terms of usability, task execution time, ease of use and comfort.

PL

W pracy przedstawiono metodykę badawczą oraz analizę wyników testu porównania dwóch metod sterowania egzoszkieletem kończyny górnej wykorzystującą sygnały o aktywności mięśni i manualne urządzenia sterownicze. Wyniki pokazują przewagę metody wykorzystującej joystick nad EMG w aspekcie użyteczności, czasu wykonywania zadania, łatwości użytkowania oraz komfortu.

9

The Research on Exoskeletons with Focus on the Locomotion Support

Wang Jikun, Lyu Linwei

Pomiary Automatyka Robotyka

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2020

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R. 24, nr 2

17--22

EN

This paper summarizes the research on exoskeletons focusing on locomotion support and presenting their general features including the general control approaches. The major fields of exoskeleton applications are focused, namely the military and medical fields. The results of our research on muscles activation during human walking are shortly described. The current developmental trends are outlined in the conclusions part.

PL

W niniejszym artykule podsumowano wyniki badań przeprowadzonych nad egzoszkieletami przeznaczonymi do wspomagania czynności ruchowych. Przedstawiono ich główne cechy, a także główne podejścia ich sterowania. Podstawowymi obszarami użycia egzoszkieletów są zastosowania wojskowe i medyczne. Opisano zwięźle wyniki badań nad aktywacją mięśni podczas chodzenia przez człowieka. Obecne trendy rozwojowe przedstawiono w podsumowaniu.

10

Application of the continuous wavelet transform for the analysis of pathological severity degree of electromyograms (EMGs) signals

Mokdad Aicha, Debbal Sidi Mohammed El Amine, Meziani Fadia

Polish Journal of Medical Physics and Engineering

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2020

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Vol. 26, Iss. 3

149--154

EN

The aim of this work was twofold: first, to propose signal processing methods for assessing the temporal and spectral changes of parameters (mean absolute value, the energy and standard deviation as temporal parameters, total and mean power as frequency parameters) of the surface myoelectric signal of the various patient groups like normal, myopathic and neuropathic during muscles contraction of biceps. Secondly, to analyze this electrical manifestation of neuromuscular disorders by the implementation of time-frequency analysis using continuous wavelet that allows us to qualify this method to evaluate, appreciate the pathology and determine its degree of severity which was unable by extracting mentioned parameters. Our results showed that this approach presents satisfactory performances especially to follow patients with the least severe pathology.

11

Comparison of muscle activity during hand rim and lever wheelchair propulsion over flat terrain

Błażkiewicz Michalina, Wiszomirska Ida, Fiok Krzysztof, Mróz Anna, Kosmol Andrzej, Mikicin Mirosław, Molik Bartosz, Marszałek Jolanta

Acta of Bioengineering and Biomechanics

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2019

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Vol. 21, no. 3

67--74

EN

The aim of this study was to compare the activity of upper limb muscles during hand rim wheelchair propulsion and lever wheelchair propulsion at two different velocity levels. Methods: Twenty male volunteers with physical impairments participated in this study. Their task was to push a lever wheelchair and a hand rim wheelchair on a mechanical wheelchair treadmill for 4 minutes at a speed of 3.5 km/h and 4.5 km/h in a flat race setting (conditions of moving over flat terrain). During these trials, activity of eight muscles of upper limbs were examined using surface electromyography. Results: The range of motion in the elbow joint was significantly higher in lever wheelchair propulsion (59.8 ± 2.43°) than in hand rim wheelchair propulsion (43.9 ± 0.26°). Such values of kinematics resulted in a different activity of muscles. All the muscles were more active during lever wheelchair propulsion at both velocity levels. The only exceptions were extensor and flexor carpi muscles which were more active during hand rim wheelchair propulsion due to the specificity of a grip. In turn, the examined change in the velocity (by 1 km/h) while moving over flat terrain also caused a different EMG timing of muscle activation depending on the type of propulsion. Conclusions: Lever wheelchair propulsion seems to be a good alternative to hand rim wheelchair propulsion owing to a different movement technique and a different EMG timing of muscle activity. Therefore, we believe that lever wheelchair propulsion should serve as supplement to traditional propulsion.

12

Sterowanie manipulatorem nasobnym w oparciu o sygnały EMG

Jankowski J., Ziemek K.

Mechanik

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2018

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R. 91, nr 7

582--584

PL

Integracja człowieka z egzoszkieletem – tak, aby poprawnie odzwierciedlał on zamiary użytkownika w zakresie ruchu kończyny górnej – wymaga zastosowania odpowiedniej metody sterowania, zawierającej algorytm wykrywania intencji. W artykule przedstawiono założenia dotyczące budowy egzoszkieletu kończyny górnej, a także proponowaną procedurę badawczą oraz wstępnie opracowane metody sterowania manipulatora wspomagającego, bazujące na analizie charakterystyki sygnału elektromiograficznego (EMG) oraz zastosowaniu sieci neuronowych.

EN

Human integration with the exoskeleton, so that it correctly reflects the intentions of the user, requires the use of an appropriate control method containing an intent detection algorithm. The article presents the assumptions concerning the construction of the upper limb exoskeleton, the preliminary research procedure and the pre-developed methods of controlling the assistance manipulator based on the analysis of the electromyographic signal (EMG) characteristics and the use of neural networks. KEYWORDS: exoskeleton, control method, EMG

13

Wpływ sposobu przenoszenia bagażu podręcznego na aktywność wybranych mięśni szkieletowych

Obrębska P., Ogrodnik J., Piszczatowski S.

Aktualne Problemy Biomechaniki

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2018

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z. 15

29--36

PL

Celem niniejszej pracy było określenie czy sposób przenoszenia bagażu podręcznego wpływa na aktywność wybranych mięśni szkieletowych. W tym celu badana była aktywność tych mięśni w czasie chodu z odpowiednio dobranym sposobem obciążenia. Podczas analizy wyników zauważono, że niesymetryczne przenoszenie bagażu powoduje zwiększoną aktywność badanych mięśni oraz wzrost asymetrii w działaniu mięśni po prawej i lewej stronie ciała.

EN

The aim on this study was to determine if and how different way of carrying hand baggage influence on selected skeletal muscles. For this purpose, the activity of these muscles was studied during gait with the appropriate load method. During the analysis of the result it was noted that asymmetric hand luggage increased the activity of the examined muscles as well as asymmetry in muscular activity on the right and left side of the body.

14

Properties of Mechatronic System for Hand Rehabilitation

Tutak Jacek Stanisław, Gurak Szymon

Advances in Science and Technology. Research Journal

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2018

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Vol. 12, no 4

103--114

EN

The article describes an innovative mechatronic device for hand rehabilitation, which enables diagnostics, comprehensive exercises and reporting the rehabilitation results of individual fingers of people who have lost their full efficiency as a result of past illnesses (i.a. stroke) and orthopedic injuries. The basic purpose of the device is to provide controlled, active exercises of the individual fingers, to widen the range of their movements, and to increase their precision of movement. The developed mechatronic device works with original software for PCs containing a diagnostic module, reporting module and a set of virtual reality exercises using biofeedback. The device uses auditory and visual biofeedback, and electromyography (EMG).

15

Project and evaluation EMG/EOG human-computer interface

Buchwald M., Jukiewicz M.

Przegląd Elektrotechniczny

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2017

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R. 93, nr 7

128--131

EN

In this paper we present Electromyography/Electrooculography (EMG/EOG) speller. It allows users to write sentences or phrases using blinking exclusively. Eye blinks are detected through simple threshold method. Moreover, the speller is comfortable to use. We based it on Open Source software available for free, as well as low-cost OpenBCI hardware. We measured the performance of the interface in an experiment. The results showed that: (1) symbols were recognised at 90% accuracy rate; (2) 100% of eye blinks was detected; (3) Information Transfer Rate (ITR) we achieved equaled 43,3 bit/min.

PL

W artykule zaprezentowano interfejs człowiek-komputer wykorzystujący Elektromiografię i Elektrookulografię. Interfejs umożliwia pisanie jedynie za pomocą wykrywanych mrugnięć. Do ich wykrywania zastosowano prostą detekcję progową. Ponadto, interfejs jest wygodny w użyciu. Bazuje on na darmowym oprogramowaniu Open Source i tanim urządzeniu OpenBCI. Przeprowadzono eksperyment testujący możliwości interfejsu. Uzyskano następujące rezultaty: (1) 90% skuteczności w rozpoznawaniu znaków; (2) 100% skuteczność w detekcji mrugnięcia; (3) Współczynnik Information Transfer Rate (ITR) wyniósł 43,3 bit/min.

16

Metody obróbki danych EMG

Serej M., Skublewska-Paszkowska M.

Journal of Computer Sciences Institute

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2017

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Vol. 3

38--45

PL

W artykule zostały przedstawione metody obróbki danych badania elektromiograficznego (EMG) oraz analiza sygnału EMG przy pomocy zaimplementowanej autorskiej aplikacji. Aplikacja służy do wczytania sygnału EMG zapisanego w pliku o rozszerzeniu .C3D. Analizę przeprowadzono pod względem największej aktywności mięśni podczas wykonywania ćwiczeń rejestrowanych przy pomocy techniki Motion Capture.

EN

The article presents both the methods of data processing of electromyography (EMG), and EMG signal analysis using the implemented piece of software. This application is used to load the EMG signal stored in a file with the .C3D extension. The analysis was conducted in terms of the highest muscles activaton during exercise recorded with Motion Capture technique.

17

The system for EMG and MMG singals recording for the bioprosthetic hand control

Wołczowski A., Błędowski M., Witkowski J.

Journal of Automation Mobile Robotics and Intelligent Systems

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2017

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Vol. 11, No. 3

22--29

EN

The process of biosignal acquisition has a significant impact on the reliability of the control of the multi-functional hand prosthesis. The paper discusses the nature of EMG and MMG signals and noise associated with their registration. The measuring system developed on the basis of these premises, as well as the measurement procedure are described.

18

The influence of aging on the isometric torque sharing patterns among the plantar flexor muscles

Oliveira L. F., Verneque D., Menegaldo L. L.

Acta of Bioengineering and Biomechanics

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2017

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Vol. 19, no. 1

41--45

EN

Purpose: Physiological cross-sectional area (PCSA) reduction of the triceps surae (TS) muscles during aging suggests a proportional loss of torque among its components: soleus, medial and lateral gastrocnemii. However, direct measurements of muscle forces in vivo are not feasible. The purpose of this paper was to compare, between older and young women, isometric ankle joint torque sharing patterns among TS muscles and tibialis anterior (TA). Methods: An EMG-driven model was used for estimating individual muscle torque contributions to the total plantar flexor torque, during sustained contractions of 10% and 40% of maximum voluntary contraction (MVC). Results: Relative individual muscle contributions to the total plantar flexion torque were similar between older and young women groups, for both intensities, increasing from LG, MG to SOL. Muscle strength (muscle torque/body mass) was significantly greater for all TS components in 40% MVC contractions. Increased TA activation was observed in 10% of MVC for older people. Conclusions: Despite the reduced maximum isometric torque and muscle strength, the results suggest small variations of ankle muscle synergies during the aging process.

19

Gait features analysis using artificial neural networks : testing the footwear effect

Wang J, Zielińska T.

Acta of Bioengineering and Biomechanics

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2017

|

Vol. 19, no. 1

17--32

EN

Purpose: The aim of this paper is to provide the methods for automatic detection of the difference in gait features depending on a footwear. Methods: Artificial neural networks were applied in the study. The gait data were recorded during the walk with different footwear for testing and validation of the proposed method. The gait properties were analyzed considering EMG (electromyography) signals and using two types of artificial neural networks: the learning vector quantization (LVQ) classifying network, and the clustering competitive network. Results: Obtained classification and clustering results were discussed. For comparative studies, velocities of the leg joint trajectories, and accelerations were used. The features indicated by neural networks were compared with the conclusions formulated analyzing the above mentioned trajectories for ankle and knee joints. Conclusions: The matching between experimentally recorded joint trajectories and the results given by neural networks was studied. It was indicated what muscles are most influenced by the footwear, the relation between the footwear type and the muscles work was concluded.

20

Experimental identification of a mathematical model of human operator working under mental stress

Kopyt A., Zużewicz K., Bartuzi P.

Acta of Bioengineering and Biomechanics

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2017

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Vol. 19, no. 3

177--185

EN

In engineering the human is considered as one of the system elements. In most studies, his/her model remains unchanged due to the external factors. The present study shows that a relation between the mental stress and human dynamics cannot be neglected. The dynamic characteristics of the operator model change due to external stimuli, i.e., mental stress. The aim of this study was to present identification of a mathematical human model and measurement methodology of the mental stress level. To determine the level of human response to external stimuli, the electrocardiography (ECG) and electromyography (EMG) methods were applied. The results showed difference in model parameters that cannot be neglected during the modeling of the human operator. The present study points to the need of developing simplified human models, taking into account external stimuli that have direct impact on his/her effectiveness. Some interdisplinary investigation provide may benefits combining part of the automation and ergonomics research areas.