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1

Kinematic evaluation of contrary body movement in sport ballroom dancing

Kuliś Szymon, Gajewski Jan

Acta of Bioengineering and Biomechanics

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2022

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Vol. 24, no. 2

120--128

EN

The aim of the study was to analyse the contrary body movement in Viennese waltz performed by dancesport athletes and to determine its relationship on scores awarded by the adjudicators. Methods: Six high-level and six intermediate dance couples took part in the study. Each couple performed three identical series of three natural turns figure in the Viennese waltz. All of them were recorded on camera while performing to music. All the trials of each couple were evaluated by 6 international adjudicators as to the technical quality component from the Absolute Judging System. A device for measuring triaxial rotational angular velocities was mounted on the dorsal part of the pelvic girdle and on the back of the chest of each athlete. Results: An analysis of covariance revealed that the mean squares of the difference in angular rotation velocity of the pelvic girdle and thoracic spine of the tested dancers were strongly associated with scores given by the adjudicators (F1.9 = 11.5, p = 0.0240, np2 = 0.449) independently of the assignment to the given group. Conclusions: The analysis and comparison of top level and intermediate athletes showed that the suggested method of measurement, presentation and analysis of the profile motion of pelvic girdle and chest motion may become a good tool for a general evaluation of the movement technique as well as a quick and effective qualitative and quantitative biomechanical assessment of selected components of movement technique in dancesport.

2

A kinematic model of a humanoid lower limb exoskeleton with pneumatic actuators

Głowiński Sebastian, Ptak Mariusz

Acta of Bioengineering and Biomechanics

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2022

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Vol. 24, no. 1

145--157

EN

Although it is well-established that exoskeletons as robots attached to the human body's extremities increase their strength, limited studies presented a computer and mathematical model of a human leg pneumatic exoskeleton based on anthropometric data. Methods: By using Inertial Measurement Units a lower limb joint angles (hip, knee and ankle in sagittal plane) during walking and running were calculated. The geometric model of a human leg pneumatic exoskeleton was presented. Joint angle data acquired during experiments were used in the mathematical model. Results: The position and velocity of exoskeleton actuators in each phase of the movement were calculated using the MATLAB package (Matlab_R2017b, The MathWorks Company, Novi, MI, USA). Conclusions: The obtained results demonstrate the efficiency of the proposed approach that can be utilized to analyze the kinematics of pneumatic exoskeletons using the dedicated design process. The developed mathematical model makes it possible to determine the position of lower limb segments and exoskeleton elements. The proposed model allows for calculating the position of the human leg and actuators' characteristic points.

3

On the improvement of calibration accuracy of parallel robots – modeling and optimization

Bentaleb Toufik, Iqbal Jamshed

Journal of Theoretical and Applied Mechanics

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2020

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Vol. 58 nr 1

261--272

EN

This paper proposes kinematic based calibration methods for Delta parallel robots. The boundary of the robot workspace is computed using a forward kinematic model. Influence of errors in kinematic parameters on the workspace boundaries is investigated. The novelty of the proposed approach lies in Jacobian-based computation of kinematic models. Also, the present work extends and applies the existing calibration methods traditionally meant for serial robots on the Delta robot. These methods include the forward method and the inverse method. Simulation results confirm the efficacy of the proposed calibration strategies.

4

KinematiC PPP using mixed GPS/GLONASS single-frequency observations

Hamed Mostafa, Abdallah Ashraf, Farah Ashraf

Artificial Satellites : Journal of Planetary Geodesy

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2019

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Vol. 54, No. 3

97--112

EN

Nowadays, Precise Point Positioning (PPP) is a very popular technique for Global Navigation Satellite System (GNSS) positioning. The advantage of PPP is its low cost as well as no distance limitation when compared with the differential technique. Singlefrequency receivers have the advantage of cost effectiveness when compared with the expensive dual-frequency receivers, but the ionosphere error makes a difficulty to be completely mitigated. This research aims to assess the effect of using observations from both GPS and GLONASS constellations in comparison with GPS only for kinematic purposes using single-frequency observations. Six days of the year 2018 with single-frequency data for the Ethiopian IGS station named “ADIS” were processed epoch by epoch for 24 hours once with GPS-only observations and another with GPS/GLONASS observations. In addition to “ADIS” station, a kinematic track in the New Aswan City, Aswan, Egypt, has been observed using Leica GS15, geodetic type, dual-frequency, GPS/GLONASS GNSS receiver and singlefrequency data have been processed. Net_Diff software was used for processing all the data. The results have been compared with a reference solution. Adding GLONASS satellites significantly improved the satellite number and Position Dilution Of Precision (PDOP) value and accordingly improved the accuracy of positioning. In the case of “ADIS” data, the 3D Root Mean Square Error (RMSE) ranged between 0.273 and 0.816 m for GPS only and improved to a range from 0.256 to 0.550 m for GPS/GLONASS for the 6 processed days. An average improvement ratio of 24%, 29%, 30%, and 29% in the east, north, height, and 3D position components, respectively, was achieved. For the kinematic trajectory, the 3D position RMSE improved from 0.733 m for GPS only to 0.638 m for GPS/GLONASS. The improvement ratios were 7%, 5%, 28%, and 13% in the east, north, height, and 3D position components, respectively, for the kinematic trajectory data. This opens the way to add observations from the other two constellations (Galileo and BeiDou) for more accuracy in future research.

5

Kinematic-PPP using single/dual frequency observations from (GPS, GLONASS and GPS/GLONASS) constellations for hydrography

Farah Ashraf

Artificial Satellites : Journal of Planetary Geodesy

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2018

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Vol. 53, No. 1

37--46

EN

Global Positioning System (GPS) technology is ideally suited for inshore and offshore positioning because of its high accuracy and the short observation time required for a position fix. Precise point positioning (PPP) is a technique used for position computation with a high accuracy using a single GNSS receiver. It relies on highly accurate satellite position and clock data that can be acquired from different sources such as the International GNSS Service (IGS). PPP precision varies based on positioning technique (static or kinematic), observations type (single or dual frequency) and the duration of observations among other factors. PPP offers comparable accuracy to differential GPS with safe in cost and time. For many years, PPP users depended on GPS (American system) which considered the solely reliable system. GLONASS’s contribution in PPP techniques was limited due to fail in maintaining full constellation. Yet, GLONASS limited observations could be integrated into GPS-based PPP to improve availability and precision. As GLONASS reached its full constellation early 2013, there is a wide interest in PPP systems based on GLONASS only and independent of GPS. This paper investigates the performance of kinematic PPP solution for the hydrographic applications in the Nile river (Aswan, Egypt) based on GPS, GLONASS and GPS/GLONASS constellations. The study investigates also the effect of using two different observation types; single-frequency and dual frequency observations from the tested constellations.

6

Slope stability analysis in open pit mines of Jebel Gustar career, NE Algeria – a multi-steps approach

Zahri F., Boukelloul M. L., Hadji R., Talhi K.

Mining Science

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2016

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Vol. 23

137--146

EN

Several types of instabilities can menace the personnel and equipment in the open cast mines. Their kinematicis dependent commonly on the nature, the structure, the fracturing and the strength of the rock mass. A scientific assessment vis-a-vis their equilibrium is suggested. For this task a considerable amount of field work must already carrying out to supply the necessary data ie: geometric, mechanic and geologic parameters. The main purpose of this research is identifying different modes of slope failures that may develop on the career “ENOF” of Jebel Gustar, by a multi-step analysis. For this task, i) a structural analysis; ii) an estimation of the rock mass and discontinuity mechanical properties, iii) a rating of the rock mass quality, iv) and a numerical simulation of the stability are procedurally used. The results matched well with the field observations. They proved the poor stability of the career, showing a typical example of a bad slope-design. The application of such approaches can help stabilizing the mine and ensure the safety and a sustainable production.

7

Kinematic Control of a Mobile Robot Performing Manufacturing Tasks on Non-Planar Surfaces

Qualls J., Canfield S., Shibakov A.

Journal of Automation Mobile Robotics and Intelligent Systems

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2016

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Vol. 10, No. 3

12--21

EN

Mobile robotic systems are becoming viable technologies for automating manufacturing processes in fields that traditionally have seen little automation. Such fields include pipeline construction, green energy development, infrastructure and shipbuilding. To operate in these environments, the mobile robotic platform must provide controlled motion of a manufacturing toolset over the surface of a structure which is generally non-planar. One such example is welding a seam along a non-flat ship hull where the surface may consist of sections resembling common geometric shapes such as cylinders or spheres and the tool must follow a path defined by the weld seam. This paper will present a kinematic control approach applicable to one mobile robot topology performing a task on a cylindrical surface. This method is readily generalized to other robot topologies or surface geometries. The method is based on a kinematic model that predicts the robot motion and configuration joint parameters while on a nonplanar surface with the desired motion prescribed in local tool space. The effort is motivated by a practical application of welding on steel hulls or other surfaces and the results will be compared with these empirical experiences. A discussion of how these results can be used to guide future design of mobile robot platforms for manufacturing is provided.

8

Relationship between performance, dry-land power and kinematics in master swimmers

Espada M. C., Costa M. J., Costa A. M., Silva A. J., Barbosa T. M., Pereira A. F.

Acta of Bioengineering and Biomechanics

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2016

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Vol. 18, no. 2

145--151

EN

The purpose of the study was to analyze the relationships between sprint swimming performance, dry-land power, and kinematics in master swimmers. Twenty-two male master swimmers were separated in two groups based on their chronological age: (i) 30–39 years and; (ii) 40–49 years. Maximum dry-land power was determined through counter movement jump and 3 kg medicine ball throwing (Hmax and Tmax, respectively). Kinematic determinants of performance were measured during a maximal bout of 15, 25 and 50 m front crawl (T15, T25, T50). Stroke frequency (SF), stroke length (SL) and stroke index (SI) were calculated as kinematical aspects of the stroke. In the 30-39 group, SI25 was correlated to T25 (r = –0.76, p < 0.01, η2 = 0.96), the same was observed between SI50 and T50 (r = –0.83, p < 0.01, η2 = 0.96). Only SI50 was significantly correlated to T50 (r = –0.86, p < 0.01, η2 = 0.97) in the 40–49 years age cohort. In dryland power variables, Hmax and Tmax were only correlated in the younger master swimmers group (r = –0.87, p < 0.01, η2 = 0.97). There were no significant differences (p < 0.05) between younger (30–39 years) and older (40–49 years) swimmers groups in dry-land tests (Hmax 28.5 ± 5.9 vs. 26.5 ± 3.9 cm and Tmax 4.2 ± 1.0 vs. 4.2 ± 1.1 m). Our results suggest that swimming performance in younger master swimmers (30–39 years) seem more dependent on kinematic swimming variables than on strength parameters, which were most related to swimming performance in the older master swimmers (40–49 years).

9

Kinematic analysis of the finger exoskeleton using MATLAB/Simulink

Nasiłowski K., Awrejcewicz J., Lewandowski D.

Acta of Bioengineering and Biomechanics

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2014

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Vol. 16, no. 3

129--134

EN

A paralyzed and not fully functional part of human body can be supported by the properly designed exoskeleton system with motoric abilities. It can help in rehabilitation, or movement of a disabled/paralyzed limb. Both suitably selected geometry and specialized software are studied applying the MATLAB environment. A finger exoskeleton was the base for MATLAB/Simulink model. Specialized software, such as MATLAB/Simulink give us an opportunity to optimize calculation reaching precise results, which help in next steps of design process. The calculations carried out yield information regarding movement relation between three functionally connected actuators and showed distance and velocity changes during the whole simulation time.

10

Effect of engine oil degradation in city type of operation part 1: Extreme case of operation in the city

Marko M., Štiavnicky M.

Zeszyty Naukowe Instytutu Pojazdów / Politechnika Warszawska

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2013

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z. 5/96

67--76

EN

The paper deals with the impact of deterioration factors on the degradation of motor oils from the viewpoint of its selected parameters in vehicles operation. Vehicles were operated on the roads, on the off road ground even under the so called intermittent operation with a number of cold starts and “go-stop“ type of driving. Motor oils were tested using TRIBO-I tribodiagnostic kit. The paper points on the change in parameter values after contamination of engine lubrication system of the vehicle with fuel, water and glycol compounds.

PL

Artykuł dotyczy wpływu najbardziej istotnych czynników wpływających na degradację olejów silnikowych, z punktu widzenia wybranych parametrów w eksploatacji pojazdów. Pojazdy były eksploatowane na drogach, poza drogami utwardzonymi, w warunkach pracy przerywanej z dużą liczba zimnych rozruchów oraz w czasie jazdy w warunkach "go-stop". Oleje silnikowe badano za pomocą zestawu do tribodiagnostyki “TRIBO-I”. W referacie zwrócono na zmiany wartości parametrów po zanieczyszczeniu układu smarowania silnika pojazdu: paliwem, wodą i związkami glikolu.

11

Effect of engine oil degradation in city type of operation. Part 2: Long term monitoring of city operation type on GOLF VI TDI vehicle

Marko M., Štiavnický M.

Zeszyty Naukowe Instytutu Pojazdów / Politechnika Warszawska

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2013

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z. 5/96

77--87

EN

Artykuł dotyczy wpływu najbardziej istotnych czynników wpływających na degradację olejów silnikowych, z punktu widzenia wybranych parametrów w eksploatacji pojazdów. Pojazdy były eksploatowane na drogach, poza drogami utwardzonymi, w warunkach pracy przerywanej z dużą liczba zimnych rozruchów oraz w czasie jazdy w warunkach "go-stop". Oleje silnikowe badano za pomocą zestawu do tribodiagnostyki "TRIBO-I". W referacie zwrócono na zmiany wartości parametrów po zanieczyszczeniu układu smarowania silnika pojazdu: paliwem, wodą i związkami glikolu.

12

Zastosowanie języka Visual Basic w projektowaniu i analizie kinematycznej w systemie Catia V5

Kania M.

Postępy Nauki i Techniki

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2011

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nr 8

12-19

PL

Przedmiotem niniejszej publikacji jest zastosowanie języka VB do sterowania modelem kinematyki mechanizmu w systemie CatiaV5. Proces ten realizowany jest poprzez zewnętrzny, specjalnie utworzony do tego celu formularz graficzny. Tworzenie programów sterujących jest istotnym czynnikiem tworzenia wirtualnego modelu kinematyki mechanizmów o znacznej złożoności, przy uwzględnieniu praw i własności ruchu w postaci równań kinetycznych. Możliwość szybkiego podglądu istotnych parametrów ruchu oraz ich zmiany, jest ich największym atutem.

EN

This publication contain information about usage of Visual Basic programming language to modeling new parts and steering of kinematic models in CatiaV5. Build external control programs is important element of creating virtual mechanism with high advance degree. In this publication present the control application for virtual helicopter rotor steering system.

13

Digital Road Profile using kinematic GPS

Farah A.

Artificial Satellites : Journal of Planetary Geodesy

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2009

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Vol. 44, No. 3

95--101

EN

A Digital Road Profile (DRP) is a digital representation of road surface topography or terrain in the longitudinal direction. The need for accurate DRP is vital in two stages; before the road construction starts and after the road construction finished where the verification of its geometrical characteristics is essential for engineering safety purposes. Classical surveying techniques are traditionally used for the DRP generation with limitation of high-cost and time-waste. Kinematic DGPS or Real Time Kinematic DGPS positioning can provide accurate enough results for such application. This paper presents an assessment study of using kinematic GPS technique for DRP generation comparing with classical survey in south Egypt. The results shows that, vehicle-GPS system used in combination with post processing kinematic DGPS gave satisfactory accuracy for nearly all points for a distance of nearly 2 km. with max. and min. difference not more than 7.7 cm, a mean value of 0.10 cm and a Root Mean Square RMS value of 4.11 cm.

14

Analiza kinematyki ruchów kończyny górnej podczas wykonywania ćwiczeń rehabilitacyjnych metodą PNF

Michnik R., Jurkojc J., Rak Z., Mężyk A., Paszenda Z., Rycerski W., Janota J., Brandt J.

Modelowanie Inżynierskie

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2008

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T. 5, nr 36

243-248

PL

W ramach pracy przeprowadzono badania kinematyki ruchów kończyny górnej wykonywanych podczas ćwiczeń rehabilitacyjnych tzw. metod PNF (Prioproceptive Neuromuscular Facilitation). Badania zrealizowano przy pomocy systemu do analizy ruchu APAS. Ruchy wykonywane przez fizjoterapeutę rejestrowane były przez zestaw siedmiu kamer cyfrowych firmy. Basler. Przebiegi kinematyczne charakterystycznych punktów antropometrycznych zostały poddane dalszej obróbce w autorskim programie TRAJGEN, w celu wyznaczenia położeń środków poszczególnych stawów kończyny górnej oraz określenie przemieszczeń kątówych poszczególnych segmentów. Wyniki uzyskane w pracy znalazły zastosowanie przy opracowywaniu konstrukcji projektowanego urządzenia rehabilitacyjnego.

EN

Research into kinematic analysis of the upper limb motion during exercises caring out according to the PNF (Prioproceptive Neuromuscular Facilitation) method is presented in the paper. Research was realised with the help of the APAS System. All movements, performed by physiotherapeutist, were recorded by seven, suitably placed, Basler camcorders. Kinematic courses of characteristic anthropometrics points, were processed in the TRAJGEN computer program in order to determine centres of individual joints of the upper limb and angle displacements of individual segments. Results were used during designing process of rehabilitation device.

15

Accuracy assessment of Digital Elevation Models using GPS

Farah A., Talaat A., Farrag F. A.

Artificial Satellites : Journal of Planetary Geodesy

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2008

|

Vol. 43, No. 4

151--161

EN

A Digital Elevation Model (DEM) is a digital representation of ground surface topography or terrain with different accuracies for different application fields. DEM have been applied to a wide range of civil engineering and military planning tasks. DEM is obtained using a number of techniques such as photogrammetry, digitizing, laser scanning, radar interferometry, classical survey and GPS techniques. This paper presents an assessment study of DEM using GPS (Stop&Go) and kinematic techniques comparing with classical survey. The results show that a DEM generated from (Stop&Go) GPS technique has the highest accuracy with a RMS error of 9.70 cm. The RMS error of DEM derived by kinematic GPS is 12.00 cm.

16

Symulacja komputerowa i weryfikacja doświadczalna kinematyki płynięcia wyciskania złożonego wyprasek z aluminium dla różnych wartości pochyleń wkładek matrycowych

Thomas P., Chałupczak J.

Zeszyty Naukowe Politechniki Świętokrzyskiej. Nauki Techniczne

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2006

|

Z. 1 [Terotechnologia 2006]

97-106

PL

W artykule prezentowane są wyniki badań i analiza symulacji komputerowej kinematyki płynięcia materiału w kierunku współbieżnym, jak i przeciwbieżnym wyciskania złożonego swobodnego dla dwóch różnych wartości kątów pochylenia wkładek matrycowych. Dla tych samych wartości odkształceń względnych w kierunku współbieżnym, jak i przeciwbieżnym, przedstawiono również weryfikację doświadczalną wyników uzyskanych w symulacji.

EN

The paper presents results of the investigation and analysis of computer simulation of kinematics of forward and backward material flow in free backward extrusion for two different values of angles of dies slopes. For the same values of relative backward and forward deformations, results obtained through computer simulations are also presented.

17

Applications of evolutionary strategies in optimal design of mechanical systems

Datoussaid S., Guerlement G., Descamps T.

Foundations of Civil and Environmental Engineering

|

2006

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No. 7

35-51

EN

This paper is concerned with the optimization of structural systems. On one hand it concerns the kinematic or dynamic behaviour of multibody systems. On the other hand it concerns the minimum weight desmg of frames according to static and dynamic constraints. The authors first recall the classical form of an optimization problem, whose purpose is to find the set of design variables which minimizes a given objective function while verifying potentialconstraints. After recalling the principal optimization techniques, the evolutionary strategies are presented in detail. They are inspired from the natural evolution: the genes of individuals mutate from generation to generation and the survivings are those being the best fitted to their environment. The analogy with an optimization problem is quite straightforward: a set of design variables can be considered as the genes of an individual and the value of the objective function for this set of design variables represents the fitness for survival of the corresponding individual. Practically, the mutation is performed by modifying the design variables of μ parents, according to a normal distribution with zero as average and gives rise to offsprings whose best μ individuals form the new parent population. The paper gives some indica tions for the choice of the principal parameters or options and explains how to manage the mutation in order to control the speed of convergence. The performances of the evolutionary strategies are then illustrated by three examples: the structural optimization of a two-storey steel frame, the kinematic optimization of a suspension and the dynamic optimization of the comfort of a railway vehicle. Evolutionary strategies, although slower than hill-climbing methods, arc an interesting alternative. They indeed have several advantages: the optimization engine remains completely independent of the simulation one and can be adapted to any field of engineering, they are very robust and converge to global and not local optimal solutions.

18

Złożone ruchy osi obrotowych sterowanych numerycznie

Staniek R.

Archiwum Technologii Maszyn i Automatyzacji

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2006

|

Vol. 26, nr 2

201-210

PL

W artykule przedstawiono zależności matematyczne pozwalające jednoznacznie określić położenie w przestrzeni obróbczej osi narzędzia głowicy wrzecionowej i osi przedmiotu obrabianego zamocowanego na stole obrotowym. Analiza dotyczy centrum obróbkowego charakteryzującego się pełnymi możliwościami kinematycznymi wykorzystania cech osi obrotowych.

EN

In that article the mathematical dependencies allowing to calculate the location of the tool and the, mounted on a rotary table, workpiece axes in the machine tool space are presented. The machine tool is intended to be able to use all the possibilities of its rotary axes.

19

Walcowanie gwintu dwiema rolkami metodą styczną

Łyczko K.

Zeszyty Naukowe Politechniki Poznańskiej. Budowa Maszyn i Zarządzanie Produkcją

|

2004

|

Nr 1

47-51

PL

Artykuł dotyczy technologii walcowania gwintów zewnętrznych przy stycznym posuwie rolek w stosunku do powierzchni gwintowanej. Przedstawiono w nim kinematyczne zależności w układzie między rolkami oraz rolkami a przedmiotem obrabianym. Omówiono dobór parametrów obróbki i metodykę obliczania wymiarów rolek walcujących.

EN

Technology of rolling external threads at tangential feed of rollers in relation to threading surface has been presented. Kinematic relationships in rollers system and between roller and object system has been discussed. Selection of treatment parameters, methodology of calculating of thread rollers dimensions have been also presented.

20

Symulacje i analizy kinematyczne w systemie Catia

Wyleżoł M.

Zeszyty Naukowe Katedry Mechaniki Stosowanej / Politechnika Śląska

|

2004

|

z. 23

481-486

PL

Referat dotyczy przeglądu podstawowych możliwości, jakie dostarcza system CATIA w kontekście analiz i symulacji kinematycznych makiet układów rzeczywistych. W szczególności zostały przedstawione narzędzia programowe służące realizacji symulacji i analiz kinematycznych, realizowanych w module DMU Kinematics systemu CATIA. W artykule wykorzystano prace własne autora, jak również wyniki prac dyplomowych magisterskich zrealizowanych pod opieką autora w Katedrze Podstaw Konstrukcji Maszyn.

EN

Development of such product consists of several characteristics stages. Creating of the prototype is one of them. The prototype is used to specify operational researches. The environment and experimental conditions of researches are known by researchers. Nowadays, operating prototypes quite often proceeds by digital models of real prototypes. The are called the digital mock-ups. Operational researches using a digital mock-ups are called a virtual prototyping. Simulations and kinematics analysis are most important elements of the virtual prototyping. Practical realization of virtual prototyping is closely connected with the computer systems, called - CAx (CAD/CAM/CAE) computer systems are usually applied to this target. One of such systems is CATIA, which belongs to the CAx group of systems. In this paper the author will present some digital mock-ups of machines and the results of kinematics analysis carried out on it. The modeling process and kinematics analysis were made with aid of CAx-CATIA system.