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1

Muscle coordination analysis by time-varying muscle synergy extraction during cycling across various mechanical conditions

Esmaeili Javad, Maleki Ali

Biocybernetics and Biomedical Engineering

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2020

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Vol. 40, no. 1

90--99

EN

Central nervous system (CNS) uses the combination of a small number of motor primitives, named muscle synergies, for simplification of motor control in human movement. The aim of this study was to investigate the muscle coordination in both leg muscles during pedaling by time-varying muscle synergy extraction. Twenty healthy subjects performed three 6-min cycling tasks over a range of rotational speed (40, 50, and 60 rpm) and resistant torque (3, 5, and 7 N/M). Surface electromyography signals were recorded during pedaling from eight muscles of the right and left lower limbs. We extracted four time-varying muscle synergies from sEMG patterns. Mean and standard deviation of the quality of the signal reconstruction (R2) for all subjects was obtained 0.9328 ± 0.0120. We investigated the similarity of muscle synergies during cycling across various mechanical conditions. We found the high degrees of similarity (>0.85) among the sets of time-varying muscle synergies across mechanical conditions and also across subjects. Our results show that the same motor control strategies for cycling are used by all subjects in various mechanical conditions.

2

Constraints on variation of weight-shifting by foot during walking in adolescents with valgus alignment of hallux

Latour Ewa, Arlet Jarosław, Latour Marek, Dworak Lechosław B., Bohatyrewicz Andrzej

Acta of Bioengineering and Biomechanics

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2020

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Vol. 22, no. 3

95--104

EN

Purpose: Etiology of hallux valgus (HV) remains unclear and effective treatments and prophylaxis for this condition are lacking and conclusions of researches concerning HV are inconsistent. Recognition of the function-structure interrelation in foot at the early stage of valgus alignment of first metatarsophalangeus joint (1stMTPJ) would help explain the etiology of HV. Methods: The frequency of weight-shifting patterns during walking and the body mass index (BMI) were assessed relative to goniometric measurements of the 1stMTPJ angle in adolescents. Weight-shifting patterns were identified with a plantar pressure analysis, performed with the GaitlineMaxline Distance method. Results: As the 1stMTPJ angle widened, the frequency distributions of identified weight-shifting patterns became increasingly lopsided, due to the favoring or disfavoring of one pattern at the expense of the other. The two sexes showed opposite trends in the weight-shifting patterns that were favored/disfavored, relative to participants with a 0º 1stMTPJ angle. The clear predominance of a central-shift pattern, at the expense of a medial-shift, occurred with the largest (20º) 1stMTPJ angle among girls. Additionally, the BMI distributions associated with 1stMTPJ angle characteristics showed opposite trends between the sexes. Conclusions: Valgus alignment of 1stMTPJ among adolescents were associated with limitations in weight-shifting freedom of the foot during walking, that could be involved in maintaining balance. An 1stMTPJ angle of 20º, where distinct limitations were observed, might serve as a criterion of HV pathology.

3

Abdominal muscles activity during abdominal bracing and posterior pelvic tilt in women after natural birth and after caesarean delivery

Kuciel Natalia, Mazurek Justyna, Biernat Karolina, Pawik Łukasz, Sutkowska Edyta

Acta of Bioengineering and Biomechanics

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2020

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Vol. 22, no. 4

167--173

EN

Exercises after pregnancy can reduce the severity and risk of postnatal locomotor system disorders and muscular dysfunctions. The aim of the study was to evaluate electromyographic activity of abdominal muscles in women who gave birth naturally and via a caesarean section, and to compare it to a group of women who have never given birth. Methods: 27 women were included into the study after completing the personal questionnaire and functional examination. The surface electromyography during abdominal bracing and posterior pelvic tilt was used to test rectus abdominis muscles and internus oblique/ transversus abdominis muscles bilaterally. After normalization test, patients were asked to perform abdominal bracing and posterior pelvic tilt exercises. Results: Activity of rectus abdominis muscle is higher in posterior pelvic tilt compared to abdominal bracing. It should be noted that the internus oblique/transversus abdominis muscle activity in both exercises is similar. Conclusions: In women after natural birth and after a cesarean section who experienced no locomotor system symptoms, no statistically significant differences in abdominal muscle activity in both exercises were observed. In each group being studied, posterior pelvic tilt activated rectus abdominis muscles to a greater extent than just bracing.

4

Wpływ ustawienia instalacji gazowej na parametry pracy silnika spalinowego o zapłonie iskrowym

Kołodziej S.

Autobusy : technika, eksploatacja, systemy transportowe

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2018

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R. 19, nr 6

506--512, CD

PL

Wysokie ceny paliw skłaniają użytkowników pojazdów do szukania alternatywnych rozwiązań zasilania silników spalinowych. Najpopularniejszym sposobem na redukcję kosztów paliwa jest montaż instalacji LPG. Poprawność działania dwupaliwowego układu zasilania uwarunkowana jest poprawnym montażem instalacji gazowej oraz odpowiednim ustawieniem parametrów sterownika LPG. W artykule skupiono się na działaniu korekt krótko- i długoterminowych realizowanych przez sterownik silnika benzynowego. Za pomocą zmian w nastawach sterownika instalacji gazowej wprowadzono niekorzystne dla pracy silnika korekty składu mieszanki gazu, które badano pod wpływem emisji szkodliwych substancji. Wykazano wyraźne zmiany w parametrach pracy silnika przed i po wprowadzeniu modyfikacji. W badaniach pokazano różnice między krótko- i długoterminowymi korektami zarówno w mocy silnika, jak i w składzie spalin.

EN

High fuel prices cause vehicle users to seek cheaper alternatives for fuelling IC engines. The most popular way of reducing fuel costs is the instalation of an LPG gas system. Correct operation of a bi-fuel engine powering system is dependent on proper installation and setup of the LPG system, including proper regulation of LPG management unit parameters. The focus of this work was to investigate the effect of short- and long-term adjustments performed by the engine management unit. By interfering with LPG management unit parameters, disadvantageous adjustments in fuel-air ratio were made to investigate harmful substance emissions. Substantial differences in exhaust gas composition were shown before and after adjustments were made. The research results included the effect of short- and long-term adjustments on both engine power and exhaust gas composition.

5

Bezczujnikowy sterownik silnika BLDC małej mocy do układu komfortu pojazdów samochodowych

Sadowski E., Pakosz A.

Autobusy : technika, eksploatacja, systemy transportowe

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2018

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R. 19, nr 6

708--711, CD

PL

W artykule omówiono sterowanie silnika bezszczotkowego prądu stałego małej mocy oraz zjawiska występujące w rzeczywistym silniku. Zaprezentowano także sposób sterowania bezszczotkowego silnika prądu stałego. Zrealizowano także własny sterownik małej mocy, umożliwiający płynny rozruch i kontrolę prędkości obrotowej silnika do 3 tys. obrotów i napięciu zasilającym do 32V DC. W niniejszym artykule zostały także zaprezentowane wyniki z przeprowadzonych pomiarów sterowania silnikiem BLDC używanym w pojazdach samochodowych, głównie w ciężarowych i autobusach.

EN

The article discusses low-power brushless motors and control modules that are used, among others, in trucks and buses. Also presented are methods of controlling brushless DC motors. The own low power controller was also implemented, enabling smooth start-up and control of the engine speed up to 3,000 revolutions and supply voltage up to 32V DC. This article also presents the results of the measurements of BLDC motor control used in automotive vehicles, mainly in trucks and buses.

6

Influence of dopaminergic treatment on resting elbow joint angle control mechanisms in patients with Parkinson’s disease – a preliminary report

Marusiak J., Jaskólska A., Budrewicz S., Koszewicz M., Andrzejewska R., Kisiel-Sajewicz K., Jaskólski A.

Acta of Bioengineering and Biomechanics

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2018

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Vol. 20, no. 4

75--82

EN

Heightened tonic stretch reflex contributes to increased muscle tone and a more-flexed resting elbow joint angle (EJA) in patients with Parkinson’s disease (PD). Dopaminergic medication restores central nervous system (CNS) functioning and decreases resting muscle electrical and mechanical activities. This study aimed to evaluate the effects of dopaminergic medication on parkinsonian rigidity, resting EJA, resting electrical activity (electromyography, EMG) and mechanical properties (myotonometry, MYO) of elbow flexor muscles and the associations of EJA with these muscles resting electrical activity and mechanical properties in PD patients. We also evaluated a relationship between dopaminergic treatment dose and these outcome measures values. Methods: Ten PD patients (age 68 ± 10.1 years; body mass 70 ± 16.8 kg; height 162 ± 6.6 cm; illness duration 9 ± 4.5 years) were tested during medication on- and off-phases. Resting EJA, myotonometric muscle stiffness (S-MYO) and root mean square electromyogram amplitude (RMS-EMG) were recorded from relaxed biceps brachii and brachioradialis muscles. Based on the above parameters, we also calculated the EJA/S-MYO ratio and EJA/RMS-EMG ratio. Parkinsonian rigidity was assessed using the motor section of the Unified Parkinson’s Disease Rating Scale. Results: EJA, EJA/S-MYO ratio, and EJA/RMS-EMG ratio were increased and S-MYO, RMS-EMG, and parkinsonian rigidity were decreased during the medication on-phase compared with the off-phase. In addition, the dopaminergic treatment dose was negatively correlated with S-MYO and RMS-EMG, and positively correlated with EJA/SMYO and EJA/RMS-EMG ratios. Conclusions: We conclude that dopaminergic medication-induced improvements in resting elbow joint angle in tested patients with PD are related to changes in their muscle electrical and mechanical properties.

7

Evaluation of the accuracy of the postural stability measurement with the Y-Balance Test based on the levels of the biomechanical parameters

Walaszek R., Chwała W., Walaszek K., Burdacki M., Błaszczuk J.

Acta of Bioengineering and Biomechanics

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2017

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Vol. 19, no. 2

121--128

EN

The testing of dynamic balance involves tests that assess the muscle control of spatial changes of the position of the centre of gravity over the base of support. The purpose of this work was to determine the structure of the Y-balance test and its accuracy based on the measurements of strength performance of the muscles acting on the knee joint, as well as the flexibility and balance in boys aged 14 years. Methods: The study included 43 schoolboys regularly participating in physical education lessons. The examination of postural stability was conducted with the use of the Y-balance test. The measurements of muscle strength and of resistance to fatigue of the extensors and flexors of knee joints in isometric contraction were performed on a measurement stand in a standard position with the use of tensometric sensors. The measurement of mobility range of the lower extremity joints was performed according to the SFTR. The examination of balance was performed with the use of the modified ‘Flamingo balance test’. Results: The factor structure of the Y-balance test results for the left and right lower extremities is similar and includes five principal independent factors that characterise the structure of analysed variables. They explain 76% and 74% of communality in total for the left and the right extremity, respectively. Conclusions: The extracted factor structure points to a hybrid structure of the Y-balance test and shows its accuracy in the measurements of the lower limb joint mobility and strength performance of knee joint extensors.

8

Impact of saturation modelling on the losses of electric drive controlled by QFT

Igrec D., Štumberger B., Chowdhury A., Hadžiselimović M.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 2b

92--95

EN

The aim of this paper is to present the impact of magnetic nonlinearities and saturation on the losses of an electric drive controlled by Quantitative Feedback Theory. For exact analysis of losses three magnetically different types of series wound DC motor dynamic models are presented and used in this work. As its main contribution this study shows that the modelling of magnetic nonlinearities improves control synthesis of electrical drive, which is reflected in lower energy consumption. For the purpose of control design of series wound DC motor Quantitative Feedback Theory was used.

PL

W artykule przedstawiono analizę wpływu nieliniowości magnetycznych oraz saturacji na straty w maszynie elektrycznej, sterowanej metodą QFT. Badaniom poddano modele dynamiczne trzech magnetycznie różnych, szeregowych maszyn DC. Wyniki pracy pokazują, że tego rodzaju analiza uskutecznia proces tworzenia algorytmu sterowania, co przekłada się na redukcję zużycia energii.

9

Simple cyclic movements as a distinct autism feature - computational approach

Dobosz K., Mikołajewski D., Wójcik G. M., Duch W.

Computer Science

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2013

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Vol. 14 (3)

475--489

EN

A diversity of symptoms in autism dictates a broad definition of Autism Spectrum of Disorders (ASD). Each year, the percentage of children diagnosed with ASD is growing. One common diagnostic feature in individuals with ASD is the tendency to exhibit atypical simple cyclic movements.The motor brain activity seems to generate a periodic attractor state that is hard to escape. Despite numerous studies, scientists and clinicians do not know exactly if ASD is a result of a simple yet general mechanism or of a complex set of mechanisms (either on the neural, molecular and system levels). Simulations using the biologically - relevant neural network model presented here may help to reveal the simplest mechanisms that may be responsible for specific behavior. Abnormal neural fatigue mechanisms may be responsible for motor symptoms as well as many (or perhaps all) of the other symptoms observed in ASD.

10

Saccadometry and LATER model shed light on brain plasticity in aging

Coubard O. A.

Biocybernetics and Biomedical Engineering

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2013

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Vol. 33, no. 2

125--127

EN

As frequency of falls increases in older adults, understanding how motor training programs counteract motor decline is a challenging issue. This study examined ocular saccades to test the effects of fall prevention (FP) on central motor control of older fallers. Saccades were recorded using a saccadometer in twelve participants aged 64–91 years before and after 2.5-month training in FP. We performed LATER analysis enabling us to examine the changes in motor control. FP decreased saccade latency and increased left-right symmetry of motor responses. LATER analysis showed that FP modulated decisional thresholds extending our knowledge of FP influence on motor control.

11

Sterowanie silnikiem spalinowym jako źródłem energii pierwotnej w hybrydowym układzie napędowym

Kost G., Nierychlok A.

Wybrane Problemy Inżynierskie

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2011

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nr 2

213-216

PL

W pracy przedstawiono wirtualny układ sterowania pojazdem kołowym z napędem hybrydowym spalinowo-elektrycznym, w którym silnik spalinowy pełni rolę pierwotnego źródła energii. Zastosowanie odpowiedniego algorytmu sterowania pracą silnika spalinowego pozwala na zmniejszenie ilości substancji toksycznych wydalanych do atmosfery oraz na zmniejszenie ilości zużycia paliwa. Algorytm sterowania uwzględnia zarówno warunki zewnętrzne jak i wewnętrzne badanego układu napędowego. W oczywisty sposób sterowanie silnikiem spalinowym powinno odbywać się bez ingerencji kierowcy w pracę jednostki spalinowej. To układ sterowania powinien dobierać odpowiednią prędkość obrotową do warunków pracy silnika spalinowego z wykorzystaniem synergii energii, która to w znaczący sposób poprawia dynamikę jazdy pojazdu kołowego z napędem hybrydowym.

EN

The paper presents a virtual control system of a wheeled vehicle, a hybrid petroleum-electric powertrain, in which ICE is a primary energy source. The uses of an algorithm of controling the internal combustion engine for reduce: the amount of excreted toxic substances into the atmosphere and also reduce of fuel consumption. Control algorithm should take into account both, external conditions and internal propulsion system. Clearly, control of internal combustion engine should be done without interfering with the driver in the work of the ICE unit.

12

Sterowanie silników krokowych za pomocą układów PLC

Syroka Z.

Pomiary Automatyka Kontrola

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2011

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R. 57, nr 7

691-693

PL

Praca napisana jest na podstawie badań przeprowadzonych w Katedrze Elektrotechniki i Energetyki UWM w zakresie sterowania silników krokowych wykorzystywanych do budowy systemów odnawialnych źródeł energii. Celem badań było skorygowanie ilości impulsów zadanych silnikowi z ilością kroków przez niego wykonanych. Wykonanie możliwie najlepszego układu sterowania z wykorzystaniem układów PLC oraz określenie, który sterownik daje tańsze i lepsze układy sterowania silników krokowych. Wykorzystywano do tego celu silniki krokowe bipolarne i unipolarne. Silniki sterowano za pomocą układu SMC62WP firmy Wobit sterowanego przez dwa różne sterowniki PLC. Jaden to Horner XLT OCS model: HE-XT105 a drugi Fanuc Versa Max Micro IC200UDD164. Układy PLC zostały narzucone przez system sterowania innych procesów związanych z pracą odnawialnych źródeł energii. Sterowanie silnikami krokowymi przy pomocy tych sterowników wynikło w procesie badań. Sterowniki firmy Simantic nie były wykorzystywane w projekcie.

EN

The paper presents some results of investigations performed in the Department of Electrical and Power Engineering of the University of Warmia and Mazury dealing with control of stepper motors used for building renewable energy sources. The aim of research was to match the number of impulses applied to a stepper motor with the number of steps made by the motor. The other objective was to construct a possibly best steering system using a PLC driver and to state which driver ensured cheaper and better stepper motor control devices. Bipolar and unipolar stepper motors shown in Figs. 1 and 2 were used in investigations. In the first section there are described types of stepper motor control. The motors under investigations were controlled with a SMC62WP device by Wobit using two differ-ent PLC drivers. One was Horner XLT OCS, HE-XT105 model and second one was Fanuc Versa Max Micro IC200UDD164. The motor control algorithm using an XLT driver and SMC62WP device is presented in Section 3 and its subprograms are shown in Figs. 3, 4 and 5, while the motor control algorithm using a Versa Max Micro driver and SMC62WP device is discussed in Section 4. The investigation results show that these algorithms are similar, so they are not decribed in this paper in detail, except for their main differences.

13

Podstawy modelu układu napędowego z automatyczną skrzynią biegów

Pawelski Z.

Napędy i Sterowanie

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2005

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R. 7, nr 1

30--35

PL

Na proces sterowania układem napędowym z automatyczną skrzynią biegów składają się następujące zadania: - sterowanie silnikiem; - sterowanie przekładnią hydrokinetyczną; - sterowanie stopniową skrzynią biegów. Silnik i automatyczna skrzynia biegów mają swoje indywidualne, autonomiczne sterowniki, a pracę całego układu nadzoruje sterownik nadrzędny, którego zadaniem jest wypracowanie takich żądań w stosunku do silnika i skrzyni, aby ich współpraca przebiegała optymalnie ze względu na postawione kryterium. W module nadrzędnym życzenie kierowcy „przetwarzane” jest na tzw. idealną linię sterowania, która przyporządkowuje położeniu pedału przyspieszenia: optymalne parametry silnika i przełożenie przekładni.

14

A real time plantar pressure feedback device for foot unloading

Femery V., Hespel J.M., Thevenon A., Moretto P.

Journal of Medical Informatics & Technologies

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2003

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Vol. 6

IT103--106

EN

The design and development of a plantar pressure control device, adapted to correct plantar pressure distribution patterns, is described. This device is based on the artificial return of information in real time to instantaneously reveal to subject certain events, of which he was unaware and which are difficult to quantify, such as the pressure variation generated by foot-ground contact. An acoustic alarm and visual signals, adjusted to a specific pressure load, alert the user in the case of excessive plantar pressure. So, our feedback device is designed to substitute for loss of feeling in patients who have peripheral neuropathy secondary to diabetes mellitus. The ultimate aim of this project is to prevent the development of neuropathic foot ulceration by providing both visual and auditory extrinsic sensory feedback to compensate for the malfunctioning peripheral nerves and to transmit information to the patient about dangerous conditions on the plantar surface of the feet. A trial of the device in a healthy subject is presented to evaluate whether a new gait pattern can emerge thanks to feedback from plantar pressure measurements.

15

Przetwornice częstotliwości VLT® Danfoss w rozproszonych systemach sterowania silnikami

Minksztym T.

Napędy i Sterowanie

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2002

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R. 4, nr 7/8

20--22

PL

W ciągu ostatnich kilku lat rozproszone systemy sterowania i kontroli napędami pozostają w centrum zainteresowania inżynierów i osób zarządzających wysoko wydajnymi procesami produkcyjnymi w różnych sektorach przemysłu. Firma DANFOSS zaznacza swój udział w rozwoju takich systemów, oferując przetwornice częstotliwości VLT® przeznaczone do nabudowy na maszynę lub silnik, lub wręcz tworzące z silnikiem zintegrowany układ napędowy.

16

Odważniej myśleć o zastosowaniu cyfrowego sterowania silnikami elektrycznymi

Kardach K.

Napędy i Sterowanie

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2000

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R. 2, nr 10

10--11

PL

Cyfrowe sterowanie silnikami elektrycznym projektowane od podstaw bardzo powoli wkracza do zastosowań praktycznych. Przyczyn tego stanu rzeczy jest wiele. Ogólnie można stwierdzić, że projektant sterowania musi posiadać wiedzę i umiejętności w szerokim zakresie: o pełna wiedza o silnikach i ich zabezpieczeniach, o znajomość algorytmów sterowania opartych na coraz bardziej wyrafinowanych teoriach i aparacie matematycznym, o umiejętność doboru procesora DSP i jego wykorzystania, o uruchomienie i przetestowanie aplikacji, o dobór odpowiednich narzędzi o optymalnej cenie.