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1

Docierarki i przyrządy do docierania powierzchni płaskich

Barylski Adam

Inżynieria Materiałowa

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2026

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Vol. 47, nr 3

6--13

PL

Przedstawiono przegląd modeli docierarek jednotarczowych do docierania elementów o niewielkich wymiarach, produkcji czołowych firm. Przeanalizowano kinematykę docierania jednotarczowego i występujące układy wykonawcze docierarek. Omówiono przyrządy do docierania niewielkich elementów płasko-równoległych, ich kinematykę obiegową i sposób obsługi.

EN

A review, with 15 refs., of models of single-disc lapping machines from leading manufacturers for lapping small-sized components. The kinematics of single-disc lapping and the machine’s actuators were analyzed. Devices for lapping small, flat-parallel components, their circulation kinematics, and operating procedures were discussed.

2

Projekt sportowego pistoletu maszynowego MPM 9 „Bohr”. Część IV – Wykonanie i badania makiety funkcjonalnej

Hryniewicz Michał, Magier Mariusz

Problemy Techniki Uzbrojenia

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2025

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R. 54, z. 172

99--110

PL

Celem niniejszej pracy było zaprojektowanie sportowego pistoletu maszynowego na podstawie przeglądu obecnych rozwiązań konstrukcyjnych wykorzystywanych w tego typu broni oraz stworzenie wstępnych założeń technicznych. W zakres pracy wchodził wybór naboju zasilającego pistolet maszynowy, dobór długości lufy, obliczenie średnicy zewnętrznej lufy, dobór masy zamka i sprężyny powrotnej oraz obliczenia kinematyki zamka, wykonanie modelu funkcjonalnego z wykorzystaniem techniki addytywnej, sprawdzenie poprawności działania mechanizmów broni oraz wskazanie możliwych usprawnień konstrukcyjnych. W części IV zaprezentowano wstępne badania użytkowe makiety funkcjonalnej pistoletu maszynowego MPM 9 „Bohr”, wykonanej w technologii addytywnej.

EN

The aim of this work was to design a sports submachine gun based on a review of current design solutions used in this type of weapon and to create preliminary technical assumptions. The scope of work included selection of a cartridge for the submachine gun, and selection of the barrel length, and calculation of the outer diameter of the barrel, and selection of the mass of the bolt and return spring, as well as calculation of the bolt kinematics, and preparation of a functional model using the additive technique to examine the correct operation of weapon's mechanisms, and indicate possible design improvements. Part IV presents preliminary operational tests of a functional mock-up of MPM 9 "Bohr” submachine gun, made in additive technology.

3

Calibration by diffeomorphisms of robot manipulator kinematics: a novel approach

Orozco Roberto, Ratajczak Adam

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2025

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Vol. 73, nr 2

art. no. e153230

EN

Our paper presents a nonparametric data-driven technique that can enhance the accuracy of robot kinematics models by reducing geometric and nongeometric inaccuracies. We propose this approach based on the theory of singular maps and the Large Dense Diffeomorphic Metric Mapping (LDDMM) framework, which has been developed in the field of Computational Anatomy. This framework can be thought of as a method for identifying nonlinear static models that encode a priori knowledge as a nominal model that we deform using diffeomorphisms. To tackle the kinematic calibration problem, we implement Calibration by Diffeomorphisms and obtain a solution using an image registration formalism. We evaluate our approach via simulations on double pendulum robot models, which account for both geometric and nongeometric discrepancies. The simulations demonstrate an improvement in the precision of the kinematics results for both types of inaccuracies. Additionally, we discuss the potential application of physical experiments. Our approach provides a fresh perspective on robot kinematics calibration using Calibration by Diffeomorphisms, and it has the potential to address inaccuracies caused by unknown or difficult-to-model phenomena.

4

Relationship between somatic build and kinematic indices of underwater undulatory swimming performed by young female swimmers

Nosiadek Leszek, Wądrzyk Łukasz, Staszkiewicz Robert, Żegleń Magdalena, Kryst Łukasz, Strzała Marek

Acta of Bioengineering and Biomechanics

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2025

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Vol. 27, no. 2

179--187

EN

The aim of this study was to determine the relationship between anthropometric indices and kinematic underwater undulatory swimming (UUS) variables among young female swimmers. Methods: The following parameters were determined in 34 participants (age 16.74 ± 0.70 years, World Aquatics score 561 ± 64): body height (H), mass (M) and fat percentage (BF), BMI, lengths of the lower limb (LL), thigh (LT), and calf (LC), circumferences of thigh (CT), maximum calf (CCMAX) and distal lower leg (CCDIS), skinfolds on the thigh (FT) and calf (FC), as well as foot length (FL) and width (WF), based on which an estimated foot surface area was calculated (SF). Using the kinematic analysis of UUS recordings, the following were determined: velocity (v), frequency ( f ), distance per cycle (DPC), amplitude of toe (A) and product of A × f (IAf). Pearson r correlation analysis was performed. Results: A relationship was observed between v and: CCMAX (r = 0.48), CCDIS (r = 0.39) and LF (r = 0.35). IAf was correlated with: CCDIS (r = 0.40), CCMAX (r = 0.39) and M (r = 0.35). A relationship was observed between A and FT (r = 0.45) and CT (r = 0.42), as well as DPC with FT (0.40) and CCMAX (0.37). Conclusions: The results indicate that the somatic structure has a small effect on the effectiveness and kinematic indices of UUS among young female swimmers.

5

Impact of energetic-anthropometric features on 50-m and 100-m freestyle kinematic indices in young male swimmers

Wądrzyk Łukasz, Staszkiewicz Robert, Strzała Marek, Sokołowski Kamil, Żegleń Magdalena, Kryst Łukasz, Badzińska Julia

Acta of Bioengineering and Biomechanics

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2025

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Vol. 27, no. 1

158--167

EN

The determinants of the sports results of young and adult swimmers differ, especially in sprint races (50–100 m). Their identification can be used to assess the athlete’s potential and to set appropriate requirements. The aim was to distinguish energy-anthropometric profiles (clusters) among young athletes and to characterize their kinematic indices in freestyle sprint races (50–100 m). Kinematic variables from both distances were compared in each cluster. Methods: Anthropometric indices and mechanical power of the upper limbs (arm-cranking) were determined in 43 subjects (boys, aged 12–13 years), which were used for cluster analysis. For the 50- and 100-m races the following were determined: velocity (v), stroke rate (SR), stroke length (SL) and stroke index (SI). Comparative analysis was performed between clusters and between distances. Results: The following clusters were distinguished: Large (LSP), Medium (MSP) and Small Size and Power (SSP), which differed due to anthropometric and power indices. Intergroup differences (LSP, MSP and SSP, respectively) were revealed in v50 (1.65, 1.55, 1.49 m/s), v100 (1.52, 1.41, 1.34 m/s), SL100 (1.92, 1.77, 1.72 m), SI50 (2.92, 2.65, 2.54 m/s2), SI100 (2.91, 2.51, 2.31 m/s2). In all clusters differences were revealed between v50 and v100 and SR50 and SR100. Differences in SL50 and SL100 were noticed in LSP and MSP, while in SI50 and SI100 in MSP and SSP. Conclusions: The evaluation of the technique should consider the energy-anthropometric profile of the athlete. The swimming technique need to be modified depending on the distance – also in races perceived as sprints.

6

Projekt sportowego pistoletu maszynowego MPM 9 „Bohr”. Część I –przegląd istniejących konstrukcji, wstępne założenia techniczne

Hryniewicz Michał, Magier Mariusz

Problemy Techniki Uzbrojenia

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2024

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R. 53, z. 169

47--62

PL

Celem niniejszej pracy było zaprojektowanie sportowego pistoletu maszynowego na podstawie przeglądu obecnych rozwiązań konstrukcyjnych wykorzystywanych w tego typu broni oraz stworzenie wstępnych założeń technicznych. W zakres pracy wchodził wybór naboju zasilającego pistolet maszynowy, dobór długości lufy, obliczenie średnicy zewnętrznej lufy, dobór masy zamka i sprężyny powrotnej oraz obliczenia kinematyki zamka, wykonanie modelu funkcjonalnego z wykorzystaniem techniki addytywnej, sprawdzenie poprawności działania mechanizmów broni oraz wskazanie możliwych usprawnień konstrukcyjnych. W części I zawarto przegląd istniejących konstrukcji sportowych pistoletów maszynowych oraz sformułowano wstępne założenia techniczne do projektowania.

EN

The aim of this work was to design a sports submachine gun based on a review of current design solutions used in this type of weapon and to create preliminary technical assumptions. The scope of work included the selection of a cartridge for the submachine gun, the selection of the barrel length, the calculation of the outer diameter of the barrel, the selection of the mass of the bolt and the return spring as well as the calculation of the bolt kinematics, the creation of a functional model using the additive technique, checking the correct operation of the weapon's mechanisms and indicating possible design improvements.Part I contains an overview of existing designs of sports submachine guns and formulates preliminary technical assumptions for design.

7

Projekt sportowego pistoletu maszynowego MPM 9 „Bohr”. Część III – opis głównych zespołów

Hryniewicz Michał, Magier Mariusz

Problemy Techniki Uzbrojenia

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2024

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R. 53, z. 171

23--47

PL

Celem pracy było zaprojektowanie sportowego pistoletu maszynowego na podstawie przeglądu obecnych rozwiązań konstrukcyjnych wykorzystywanych w tego typu broni oraz stworzenie wstępnych założeń technicznych. W zakres pracy wchodził wybór naboju zasilającego pistolet maszynowy, dobór długości lufy, obliczenie średnicy zewnętrznej lufy, dobór masy zamka i sprężyny powrotnej oraz obliczenia kinematyki zamka, wykonanie modelu funkcjonalnego z wykorzystaniem techniki addytywnej, sprawdzenie po-prawności działania mechanizmów broni oraz wskazanie możliwych usprawnień konstrukcyjnych. W części III przedstawiono opis konstrukcyjny głównych zespołów pistoletu maszynowego MPM 9 „Bohr”.

EN

The aim of work was to design a sports submachine gun based on a review of current design solutions used in this type of weapon and to create preliminary technical assumptions. The scope of work included the selection of a cartridge for the submachine gun, the selection of the barrel length, the calculation of the outer diameter of the barrel, the selection of the mass of the bolt and the return spring, as well as the calculation of the bolt kinematics, the creation of a functional model using the additive technique, checking the correct operation of the weapon's mechanisms and indicating possible design improvements. Part III presents the construction description of the main components of the MPM 9 "Bohr" submachine gun.

8

Projekt sportowego pistoletu maszynowego MPM 9 „Bohr”. Część II - Podstawowe obliczenia konstrukcyjne

Hryniewicz Michał, Magier Mariusz

Problemy Techniki Uzbrojenia

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2024

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R. 53, z. 170

7--37

PL

Celem niniejszej pracy było zaprojektowanie sportowego pistoletu maszynowego na podstawie przeglądu obecnych rozwiązań konstrukcyjnych wykorzystywanych w tego typu broni oraz stworzenie wstępnych założeń technicznych. W zakres pracy wchodził wybór naboju zasilającego pistolet maszynowy, dobór długości lufy, obliczenie średnicy zewnętrznej lufy, dobór masy zamka i sprężyny powrotnej oraz obliczenia kinematyki zamka, wykonanie modelu funkcjonalnego z wykorzystaniem techniki addytywnej, sprawdzenie poprawności działania mechanizmów broni oraz wskazanie możliwych usprawnień konstrukcyjnych. W części II dokonano zaprezentowano podstawowe obliczenia konstrukcyjne pistoletu maszynowego MPM 9 „Bohr”.

EN

The aim of this work was to design a sports submachine gun based on a review of current design solutions used in this type of weapon and to create preliminary technical assumptions. The scope of work included the selection of a cartridge for the submachine gun, the selection of the barrel length, the calculation of the outer diameter of the barrel, the selection of the mass of the bolt and the return spring as well as the calculation of the bolt kinematics, and the preparation of a functional model using the additive technique, checking the correct operation of the weapon's mechanisms and indicating possible design improvements. Part II presented the basic design calculations of the MPM 9 "Bohr" submachine gun.

9

Analiza wytrzymałościowa luf konstrukcji wzmocnionej i niewzmocnionej stosowanych w broni strzeleckiej wybranych kalibrów. Część III - obliczenia wytrzymałościowe luf wzmocnionych

Dąbrowski Bartłomiej, Magier Mariusz, Sweklej Paweł

Problemy Techniki Uzbrojenia

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2024

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R. 53, z. 171

7--21

PL

Celem pracy była realizacja dwóch głównych zadań badawczych. Pierwszym było zaprojektowanie sześciu luf w trzech kalibrach: 5,56x45 NATO, 7,62x51 NATO oraz 12,7x99 NATO. Dla każdego kalibru zaprojektowano po dwie lufy: jedną niewzmocnioną oraz drugą o wzmocnioną płaszczem. Drugim zadaniem było wykonanie symulacji komputerowych wytrzymałości luf z wykorzystaniem metody elementów skończonych, na podstawie których porównano obliczenia wytrzymałościowe analityczne i numeryczne oraz sformułowano wnioski. Część III obejmuje obliczenia wytrzymałościowe luf wzmocnionych dla wszystkich badanych luf.

EN

The paper describes the leading of two main research tasks. The first one dealt with designs of six barrels for three calibers: 5.56x45 NATO, 7.62x51 NATO, and 12.7x99 NATO. Two barrels were designed for each calibre: one unreinforced and the second one reinforced by a coat. The second task dealt with a computer barrel strength simulation using the method of finite elements to compare the results of numerical and analytical strength calculations and draw the conclusions. Part III includes strength calculations of reinforced barrels for all tested barrels.

10

Kinematic synthesis of the Gough-Stewart platform in ADAMS and MATLAB

Sapietová Alžbeta, Dekýš Vladimír, Mikolaj Dušan, Sapieta Milan

Journal of Applied Mathematics and Computational Mechanics

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2024

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Vol. 23, nr 3

86--96

EN

In this paper, the kinematic synthesis of a parallel Gough-Stewart platform mechanism is addressed in order to achieve the motion of the working part of the mechanism along a prescribed trajectory. A virtual prototype of this platform was created in the environment of the dynamics of systems bodies program ADAMS. In the process of cosimulation of MATLAB, MATLAB/Simulink and ADAMS, the input trajectories of actuator velocities necessary to achieve the desired motion of the effector point were identified. The trajectory was defined by parametric equations for the epitrochoid, hypocycloid, epicycloid and Archimedes spiral. The velocities of the actuators were derived by deriving the position vector of the distances between the base and platform points. The solution logic using the given software is presented by a block diagram.

11

Arduino-based implementation of kinematics for a 4 DOF robot manipulator using artificial neural network

Rashid Zaid Hikmat, Sarhan Riyadh Ahmed, Hassan Mohammed Salih

Diagnostyka

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2024

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Vol. 25, No. 1

art. no. 2024114

EN

Real-time motion control is basically dependent on robot kinematics analysis where there is no unique solution of the inverse kinematics of serial manipulators. The predictive artificial neural network is a powerful one for finding appropriate results based on training data. Therefore, an artificial neural network is proposed to implement on Arduino microcontroller for a 4-DOF robot manipulator where the inverse kinematics problem was partitioned to suit the low specification of the board CPU. With MATALB toolbox, multiple neural network configuration based were trained and experienced for the best fit of the dimensionless feedforward data that is obtained from the forward kinematics of reachable workspace with average MSE of 6.5e-7. The results showed the superior of the proposed networks reducing the joints error by 90 % at least with comparing to traditional one. An Arduino on-board program was developed to control the robot independly based on pre validated parameters of the network. The experimental results approved the proposed method to implement the robot in real time with maximum error of (± 0.15 mm) in end effector position. The presented approach can be applied to achieve a suitable solution of n-DOF self-depend robot implementation using micro stepping actuators.

12

Kinematic calibration of a lightweight manipulator for medical applications

Arent Krzysztof, Kurnicki Adam, Portasiak Piotr, Stańczyk Bartłomiej

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2024

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Vol. 72, nr 6

art. no. e151381

EN

The paper presents a kinematics calibration procedure for a lightweight manipulator designed for medical applications. They comprise improving the dexterity of a dysfunctional arm of a handicapped patient in an electric wheelchair as well as supporting biopsies and surgeries. Consequently, there are several manipulator distinguishing features of the manipulator design that are relevant to kinematics calibration. In particular, these are: a small area in the workspace within which the end-effector operates, affordability for non-commercial users, a delicate, dexterous design. In this context we propose a specialized procedure that features a low cost calibration tool enabling the end-effector to reach the correct positions for data acquisition. The key parameters of the calibration tool were obtained by applying two techniques of numerical analysis, workspace clustering and arbitrary choice, and subsequent experimental verification. The procedure exploits classical results concerning the kinematics calibration and is empirically verified by comprehensive simulation and experimental studies.

13

Architecture of time: from motion picture to computer animation

Kwiatkowska Ada

Architectus

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2023

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Nr 4 (76)

117--126

EN

The architecture of the digital era, exploring the dimension of time, refers to the concept of so-called time-based art. Present computer technologies allow one to simulate the space-time transformation of architectural objects connected with observer’s movement and to create dynamic movable spatial structures by applying smart materials and technologies to architecture. The purposes of the research are to analyse the influence of the concept of time on the shaping of architectural forms and the directions of the development of architectural forms determined by technologies discovered during the industrial and information revolutions (film techniques, computer visualisations, simulations, and animations). Based on the structural analysis of dynamic mutual relations between the observer, the architectural object, and the context, connected with comparative and critical analysis of modern trends, different types of architecture of time are distinguished. These types are derivatives of the expression of time in three-dimensional space and assumptions related to the degree of changeability and dynamics of the spatial structures (kinaesthetic, kinematic, and kinetic forms), and depend on the expression tools used in the creation and simulation of the mutability of forms. Computer animation is not only a tool, but also a way of thinking about the architectural form as an object immersed in space-time, therefore it will influence the way of designing and contribute to the emergence of a new generation of forms in the near future. Time-based architecture of the information age will explore the idea of streaming architecture.

PL

Architektura ery cyfrowej, eksplorująca wymiar czasu, nawiązuje do koncepcji sztuki tzw. time-based art. Współczesne technologie komputerowe pozwalają na symulację zmienności form architektonicznych i ich percepcji w powiązaniu z ruchem obserwatora w przestrzeni oraz tworzenie dynamicznych struktur przestrzennych dzięki zastosowaniu inteligentnych materiałów i technologii w architekturze. Celem badań było określenie wpływu koncepcji czasu na kształtowanie form architektonicznych oraz kierunków rozwoju form architektonicznych wyznaczonych przez technologie odkryte podczas rewolucji przemysłowej i informacyjnej (techniki filmowe, wizualizacje komputerowe, symulacje, animacje). Na podstawie strukturalnej analizy dynamicznych relacji między obserwatorem, obiektem architektonicznym a kontekstem, oraz porównawczej i krytycznej analizy współczesnych trendów wyróżniono różne typy architektury czasu. Typy te są pochodnymi ekspresji czasu w trójwymiarowej przestrzeni oraz założeń związanych ze stopniem zmienności i dynamiki struktur przestrzennych (formy kinestetyczne, kinematyczne i kinetyczne) i zależą od narzędzi ekspresji użytych w tworzeniu i symulacji zmienności form. Animacja komputerowa jest nie tylko narzędziem, ale też sposobem myślenia o formie architektonicznej jako obiekcie zanurzonym w czasoprzestrzeni, dlatego będzie wpływać na sposób projektowania, a także przyczyni się do pojawienia się nowej generacji form w najbliższej przyszłości. Time-based architecture oparta na wymiarze czasu architektura epoki informacji będzie eksplorowała ideę architektury streamingu.

14

Relationship of lumbar-hip kinematics during trunk flexion and sex, body mass index, and self-reported energy expenditure: a cross-sectional analysis

Zawadka Magdalena, Smołka Jakub, Skublewska-Paszkowska Maria, Łukasik Edyta, Zieliński Grzegorz, Gawda Piotr

Acta of Bioengineering and Biomechanics

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2023

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Vol. 25, no. 1

56--64

EN

Physical activity (PA) is a well-known, simple and effective preventive and therapeutic intervention for low back pain (LBP). In spite of the growing interest in active lifestyles and its benefits, more needs to be known about the relationship between energy expenditure, body mass and lumbar-pelvic kinematics during the forward bending movement in a group of young asymptomatic people who met PA guidelines. Young people can be identified as a future risk group of civilisation diseases and lumbar-hip kinematics can be considered as a predictor of LBP occurrence. The aim of this study was to identify the association of gender, self-reported energy expenditure, body mass index, and lumbar-hip kinematics in young people. Methods: Sixty-four students at pre-employment stage participated in the study. They declared moderate-to-high PA and activity-induced energy expenditure (AEE) was self-reported. Kinematic data of the lumbar spine, pelvis and hip were collected during forward bending using a 3D motion ca pture system. Results: Sex was found to be associated with pelvis ( = –0.38 p = 0.002) and lumbar mobility ( = 0.49, p < 0.001) during forward bending and BMI was related only to lumbar mobility ( = –0.41, p = 0.001). Recreation AEE significantly predicted hip flexion mobility ( = 0.38, p = 0.002). Conclusions: This study showed that among a sample of physically active young people, BMI, self-reported AEE and sex can partially predict lumbar-hip kinematics during trunk flexion. Recreational PA can be regarded as improving hip mobility and thus making forward bending more effective and less prone to injury.

15

Kinematic analysis of the basketball jump shot with increasing shooting distance: comparison between experienced and non-experienced players

Caseiro André, Faro Ana, França Cíntia, Branquinho-Gomes Beatriz

Acta of Bioengineering and Biomechanics

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2023

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Vol. 25, no. 2

61--67

EN

Basketball jump shot success is determined mainly by the height, velocity and angle of ball release. To achieve a successful shot, these variables need to be adjusted according to the player’s position on the court. This study aimed to identify the changes in kinematics variables of the basketball jump shot with an increasing shooting distance performed by players with varying skill levels. Methods: Seventeen male subjects, divided into experienced (N = 9), and non-experienced (N = 8) players, performed three successful jump shots from the free-throw line (4.23 m) and the 3-point line (6.75 m). All attempts were recorded at 120 Hz with a camera perpendicularly to the sagittal plane, and the kinematics variables were calculated using Tracker software. Results: The increase in shooting distance shows a decrease in height and angle of ball release. In contrast, the velocity of ball release increased for both groups at longer distances. Experienced players presented a higher mean value of the height of ball release in both distances, which allowed for a lower velocity of ball release. Conclusions: The most meaningful improvement for players training the jump shot technique is to increase the release height of the ball, jumping higher and shooting the ball near the peak of the jump.

16

Analysis of segmental coordination in the lower extremity using vector coding: a pilot return-to-play study of acute ankle sprain

Yang Xiaoyi, Jiang Hanhui, Yu Peimin, Mei Qichang, Fernandez Justin, Gu Yaodong

Acta of Bioengineering and Biomechanics

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2023

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Vol. 25, no. 4

23--34

EN

Background: Acute ankle sprain may affect ankle function during sport and daily activities. This study aimed to use vector coding technique to analyze the difference over time between injured and healthy lower limb during the first week of acute ankle sprain phase (P1) and post a 1-month recovery phase (P2) to understand the return-to-play coordination strategy in the lower extremity. Methods: Six females attended the gait experiments with attached 40 reflective markers using eight camera Vicon motion capture system. All participants walked barefoot while turning in four directions (T0°, T45°, T90°, T135°) at their self-selected speed. Coordination patterns were classified as in-phase, anti-phase, proximal or distal dominancy between lower limb joints involving hip, knee, ankle, subtalar, metatarsophalangeal (MTP) joint and tarsometatarsal (TMT) joint. Results: P1 showed more proximal joint dominant in Hip-Knee coupling angles but P2 displayed more distal joint dominant in Knee-Ankle joint coordination pattern and mainly distal joint dominant in Ankle-MTP coupling angle mapping. The Ankle-TMT1 and Ankle-TMT5 coordination patterns matched best in straight walking but worst in T135 walking. Conclusions: Investigating inter-segmental coordination in different turning movements could provide insights into gait changes from acute ankle sprain from one-month return-to-play recovery. Knowledge of lower limb coordination pattern may provide clinical implications to improve dynamic balance and gait stability for individuals with acute ankle sprain.

17

Rejestracja obrazów a kalibracja kinematyki manipulatorów

Orozco Roberto, Ratajczak Adam

Prace Naukowe Politechniki Warszawskiej. Elektronika

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2022

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z. 197, t. 1

21-30

PL

Referat podejmuje próbę zaadaptowania wariacyjnych metod rejestracji obrazów do kalibracji kinematyki robotów manipulacyjnych. Rozpatrzono możliwość wykorzystania dyfeomorficznego dopasowania punktów charakterystycznych (ang. Diffeomorphic Landmark Matching) jako narzędzia do obliczania przekształceń dla szczególnej metody kalibracji, mianowicie kalibracji przez dyfeomorfizmy. Sformułowano problem rejestracji obrazów oraz przedstawiono idee związane z kalibracją prze dyfeomorfizmy. Efektywność takiego podejścia została zweryfikowana badaniami symulacyjnymi dla modelu kinematyki podwójnego wahadła.

EN

The paper addresses an attempt to adapt variational methods of the image registration to the calibration of manipulator kinematics. In particular, it considers an application of Diffeomorphic Landmark Matching as a tool for computing transformations for a specific calibration method, namely the calibration by diffeomorphisms. Image registration formalism as well as the ideas underlying the calibration method has been presented. The results of bonding these two theories have been evaluated by means of simulations.

18

Odporna kinematyka odwrotna w konfiguracjach osobliwych

Dulęba Ignacy

Prace Naukowe Politechniki Warszawskiej. Elektronika

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2022

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z. 197, t. 1

5-10

PL

W referacie przedstawiono zasady konstrukcji odpornych algorytmów kinematyki odwrotnej w konfiguracjach osobliwych i ich otoczeniu, uzasadniające także klasyczny algorytm odpornej odwrotności. Zaproponowano sposób addytywny i multiplikatywny wprowadzania poprawki do macierzy źle uwarunkowanej, by przywrócić jej dobre uwarunkowanie.

EN

In this paper additive and multiplicative methods of making inverse kinematics robust at (or around) singular configurations were presented. The methods are provable good and as special case cover also the literature robust inverse kinematics method. A clear advantage of robust methods is their independence on the cornak of singularities and simplicity in implementation.

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Identyfikacja modelu robota mobilnego z użyciem adaptacyjnego obserwatora ESO

Patelski Radosław, Pazderski Dariusz

Prace Naukowe Politechniki Warszawskiej. Elektronika

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2022

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z. 197, t. 1

11-20

PL

W pracy rozważa się problem identyfikacji parametrów modelu dynamiki dwukołowego robota mobilnego z napędem różnicowym. Model dynamiki robota sformułowany został przy założeniu, że prędkości kół robota są mierzalnymi sygnałami wyjściowymi, natomiast prądy silników napędzających robota są sygnałami wejściowymi. W celu identyfikacji nieznanych parametrów robota wykorzystano zaproponowany niedawno adaptacyjny obserwator stanu rozszerzonego (PIESO) sformułowany poprzez połączenie klasycznego obserwatora stanu rozszerzonego (ESO) z gradientowym prawem adaptacji. Skuteczność proponowanego podejścia potwierdzono badaniami symulacyjnymi i eksperymentalnymi.

EN

In this paper a problem of identification of parameters of a two-wheeled mobile robot equipped with differential drive is considered. Model of the robot dynamics is formulated under an assumption that velocities of wheels are measurable outputs of the system, while the motor currents are input signals. In order to identify unknown parameters, a recent adaptive parameter identifying extended state observer (PIESO) algorithm is employed, which combines a classic ESO observer with a gradient adaptation law. The effectiveness of the proposed approach is validated by numerical and experimental trials.

20

Kinematic analysis of L4–L5 spinal segment with spondylolysis and different types of grade 1 spondylolisthesis: a nonlinear finite element study

Yaroub Suhaib, Hamandi Sadiq J., Mohson Khaleel

Acta of Bioengineering and Biomechanics

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2022

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Vol. 24, no. 2

177--186

EN

This work aimed to evaluate and characterize the motion of the fourth and fifth lumbar vertebrae functional spinal unit with spondylolysis and different types of grade 1 spondylolisthesis using the finite element method. Methods: Nine nonlinear three-dimensional finite element models were reconstructed from computed tomography scans to five educational fourth and fifth lumbar vertebrae models. The intervertebral disc was simulated in two conditions: four models with healthy discs and five models with degenerated discs. Each model consisted of two vertebrae divided into three bony parts, two endplates, an intervertebral disc and five ligaments. The flexion, extension, lateral bending and rotation loading conditions were simulated, and the ranges of motion were measured and plotted. Results: In flexion, compared to the baseline intact model, the most significant increase in the range of motion was experienced by the isthmic spondylolisthesis model, while in extension, a reduction in the range of motion was measured in both prolonged pars and unilateral pars defect and healthy disc models. In degenerated disc results, the unilateral pars defect and degenerative spondylolisthesis models had the lowest range of motion. No large differences were noticed in lateral bending results. Lastly, in axial rotation, the most significant increase in the range of motion was measured in the isthmic spondylolisthesis model, followed by the spondylolysis model and similarly, in the degenerated disc models. Conclusions: The isthmic spondylolisthesis displayed hypermobility in flexion and rotation. Moreover, the model with unilateral pars defect showed hypermobility in axial rotation only. Finally, hypomobility in all movements was noticed with the degenerative spondylolisthesis model.