Dissertations / Theses: 'Kinematika a dynamika'

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Zháňal, Lubor. "Simulace kinematiky a dynamiky vozidlových mechanismů." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2015. http://www.nusl.cz/ntk/nusl-234269.

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This paper focuses on the kinematic and dynamic numerical simulation of mechanisms by applying a numerical method, and a complex simulation programme built on it, developed by the author. Described are mathematical principles of the numerical method used and also the programming progression of the important parts of the application and its optimization. The final part includes comparative measuring of the accuracy and performance.

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Přeslička, Jaroslav. "Vyvážení tříválcového traktorového motoru." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231700.

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The thesis deals with analysis of balancing of given cranktrain. At the introductory part is solved kinematics of the crank mechanism. Another part of the text occupies with dynamics of the crank mechanism and eventuality of its balancing with using of point-mass model. This simplified model is utilized for analytic solution of given mechanism. Results of analytic solution are compared with results of MBS solution. At the last part is done analysis of minimal distance between the selected parts of the mechanism. Then simple optimization of balancing is done. At the end is considered balancing of the mechanism and simple improvement is proposed, considered are results of minimal distance analysis too.

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Řehůřek, Lukáš. "Vliv pružnosti rozvodového mechanismu na pohyb ventilu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-254396.

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The aim of this thesis is a comparing single valve train motion (SVT) and complete valve train motion with a flexible camshaft focused on dynamic characteristics. In this thesis is also performed kinematics analysis in the VALKIN software. Dynamic analysis is solved in the MBS software Virtual Engine. Influences to the valve train motion are described in the conclusion

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Křižák, Michal. "Využití počítačové podpory při řešení předstřetového pohybu vozidel." Master's thesis, Vysoké učení technické v Brně. Ústav soudního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-232640.

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Thesis deals with comparison of influence of chosen solution method on pre crash movement of vehicles in one simulation program and on differences between calculations for one method in different programs. Compared solution methods are kinematics and dynamics solutions of pre crash movement, compared programs are Virtual CRASH and PC-Crash.

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Jandora, Radek. "Výpočtové modelování dynamických projevů v kontaktu kola a kolejnice s obecnou geometrií kontaktních povrchů." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2012. http://www.nusl.cz/ntk/nusl-234020.

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During life of railway vehicles, shape irregularities develop on wheels and rails because of wear. The shape irregularities then affect forces in wheel-rail contact and cause further damage of contact surfaces, vibrations and noise and increase risk of derailment. A numerical simulation of railway vehicle motion with more details on contact surfaces geometry was created to investigate dynamic contact loads in wheel-rail contact. A variety of methods can be used to evaluate forces in rolling contact, the method chosen for this study was algorithm CONTACT based on boundary element method. Four studies are presented in this papers: contact loads from a wheel with a flat and with a wavy tread pattern, loads on wavy rail and load in a curve. The first three studies investigated effects of existing wear patterns, the last one looked for cause of common wear pattern developing on rails. Results of the studies with worn components used showed that the worst kind of shape irregularities is a flat present on wheel. This type of shape cause loss of contact and following impacts. The study of ride in curve showed that cause of high wear in curves, especially those with small radii, is caused by vibration of wheelset. This vibration is then caused by different length of inner and outer rail and wheels travelling along a different path.

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Šuranský, Michal. "Modelování, identifikace a řízení robotického manipulátoru." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230936.

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Main aim of this master’s thesis is to identify, model and control robotic manipulator with three degrees of freedom. The thesis is a part of major project [17], the aim of which is to create an educational platform. In the thesis the simple PID control and the PID with feedforward compensation control is tested on the model of simple pendulum. In the next part models of DC motors, which are used for construction of the manipulator, are developed and the inverse dynamics model of manipulator is developed. This model is used for feedforward control of the manipulator. In the final part the application was developed, which allows the manipulator to be taught some movements, which can be later on, executed. For the simple control of the application the graphical user interface was programmed.

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Jasanský, Michal. "Návrh dynamických modelů pro řízení trakce experimentálního vozidla." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-228949.

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The Master's thesis deals with the simulations kinematics and dynamics of experimental four-wheeled vehicle with all-wheel steering and all-wheel drive. Suggestion of vehicle stability systems ABS/ASR for traction control is included. There are several dynamics models with their comparison. The estimation of important vehicle parameters is implemented. Based on knowledge the simple vehicle stability system ABS/ASR is created.

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Novák, Jiří. "Návrh uložení hydraulického válce zkušebního zařízení kulových kloubů." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2009. http://www.nusl.cz/ntk/nusl-228586.

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The main object of this thesis is the proposal of fitting (setting) hydraulic cylinder into test equipment of ball-joints of company TRW-DAS Dačice a.s. The thesis includes a short review about testing ball-joint of above company and about liquid mechanisms. Also, there are analyzed demands for fitting (setting) hydraulic cylinder into testing equipment. In the main part of this thesis there is described my own constructive proposal with numeric calculations in proper software. In enclosure there are all analytical calculations with productive drawings and an assembly drawing.

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Valčík, Martin. "Hnací mechanismus Stirlingova motoru." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2018. http://www.nusl.cz/ntk/nusl-378136.

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This diploma thesis is focused on the design of the driving mechanism of Stirling engine, where was chosen modification of these engines with rhombic drive. Subsequently is constructed kinematical, dynamical and thermomechanical mathematical model. Finally, is going from these models for execution strength control and drawing documentation.

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Novák, Vít. "Pohonné ústrojí čtyřválcového řadového zážehového leteckého motoru." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-417579.

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The focus of this work is to determine the stress of the crank mechanism of the inverted piston aircraft engine Walter Mikron III C UL from the manufacturer PARMA - TECHNIK, s.r.o. The main method of calculation is the numerical finite elements method using the program ANSYS Workbench, the module Static structural and Transient structural. The approximate indicated cylinder pressure during the duty cycle was determined in the GT-SUITE software. The partial goals are to propose possible modifications in the construction of the crank mechanism and to state the possible power reserves of the engine. The diploma thesis also briefly summarizes the history and development of aircraft piston engines from the company Walter, which developed the engine, and the line of Walter Mikron engines.

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Centea, Dan Elbestawi Mohamed A. A. "Design, kinematics and dynamics of a machine tool based on parallel kinematic structure." *McMaster only, 2004.

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Nolte, Rainer. "Formatabhängige hochdynamische Bewegungen mit Servoantrieben." Universitätsbibliothek Chemnitz, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-226132.

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OPTIMUS MOTUS (R) ist ein grafischer Editor, um komplexe Bewegungsabläufe zu modellieren, zu optimieren, zu testen und schließlich als Funktionsbausteine für die SPS-Welt zu exportieren. So können SPS-Bewegungsprogramme erheblich schneller entwickelt und geändert werden als bei manueller Programmentwicklung. Die aus der Kurventechnik bekannte Bewegungsqualität kommt damit auch bei Servoantrieben zum Tragen. Das Debugging entfällt, weil die Quelltexte maschinell erzeugt werden.

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Jonszta, David. "Modelování a řízení mobilních kolových robotů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2008. http://www.nusl.cz/ntk/nusl-217194.

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The thesis deals with modelling and control of wheeled mobile robots. The thesis introduces the mathematical models of diferentially driven mobile robot, robot with Ackerman steering and a skid steered robot. The thesis describes open-loop and feedback control. Feedback control is divided into point-to-point control, path following and trajectory tracking.

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Penney, Camilla Emily. "Kinematics and dynamics of continental deformation." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/278649.

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In contrast to the oceans, deformation in the continental lithosphere is distributed over broad regions. This dissertation is composed of three separate but related studies investigating the kinematics and dynamics of such deformation. The first two studies look at the Makran subduction zone, and the third focusses on deformation in South East Tibet. The first study is an investigation of the 11 May 2013 M w 6.1 Minab earthquake which occurred at the western end of the Makran subduction zone, adjacent to the transition to continent-continent collision in the Zagros mountains. Seismological, geodetic and field results are used to study the source parameters and slip distribution of this earthquake, and demonstrate that the earthquake was left-lateral and occurred on a fault striking ENE–WSW; approximately perpendicular to previously studied faults in the adjacent Minab-Zendan-Palami fault zone. Geological and geomorphological observations of similar faults in the vicinity are used to infer that vertical-axis rotations allow a series of such faults to accommodate ∼15–19 mm/yr of N–S right-lateral shear. The dynamic implications for the transition between subduction and continental collision are discussed. The second study looks at the Makran region as a whole. First, the shape and depth of the interface with the Arabian plate is constrained by modelling the depths and mechanisms of earthquakes across the region, and combining these with additional seismological constraints. These constraints on the subduction interface are used to investigate elastic strain accumulation on the megathrust in the western Makran, which has important implications for seismic and tsunami hazard in the region. Second, the kinematics at the northern edge of the Makran accretionary prism are investigated using a combination of geodetic and geomorphological observations, addressing the long-standing tectonic problem of how the right-lateral shear taken up by strike-slip faulting in the Sistan Suture Zone in eastern Iran is accommodated at the zone’s southern end. Finally, the kinematics and dynamics of the accretionary prism are investigated. By considering the kinematics of the 2013 Balochistan and Minab earthquakes, local gravitational and far-field compressive forces in the Makran accretionary prism are inferred to be balanced. This force balance allows the mean shear stress and effective coefficient of friction on the Makran megathrust to be calculated, 5–35 MPa and 0.01–0.03 respectively. The final part of this thesis focusses on the temporal evolution of topography in South East Tibet. Recently published paleoaltimetry results based on stable-isotope geochemistry are used to provide constraints on vertical motions. These demonstrate that uplift is much slower than had previously been suggested from thermochronometric data. Numerical modelling of the time evolution of a gravitationally-driven fluid is used to investigate the effect of lateral rheological contrasts on the shape and evolution of topography. In such a flow, material at the surface can be transported hundreds of kilometres, an effect which should be accounted for in paleoaltimetric analysis. Lateral rheological contrasts, analogous to the relatively undeforming Sichuan Basin and Central Lowlands of Myanmar, can reproduce the main features of the present-day topography, GPS velocity field and earthquake-derived strain rate without the need for a low-viscosity lower-crustal channel.

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Glombová, Pavla. "Stanovení viskozity pro různé typy splaškových vod." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-227747.

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The aim of this diploma thesis is a description of viscosity as a physical characteristic of liquids, next a description of projecting different types of sewer systems (pressure sewer system, vacuum sewer system and gravity sewer system). There was a range of density and viscosity of wastewater experimentally determined. These values were compared with ordinary values used in practice. The practical part of this work consists of sampling wastewater from different types of sewer systems and various localities. Chemical-biological analysis was realized on those samples with defined density, then dynamic viscosity was measured by the rotary viscometer for various temperatures. Measured data are evaluated. Finally, a calculation related to the design of sewers was made.

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Xu, Qing Song. "Kinematics, dynamics and control of parallel robots." Thesis, University of Macau, 2004. http://umaclib3.umac.mo/record=b1446180.

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Bařinka, Martin. "Elektronická stabilizace podvozku Formule Student." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2020. http://www.nusl.cz/ntk/nusl-413184.

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Goal of this semestral thesis is development of chassis electronic stability control ESP. Thesis analyze kinematic model of chassis, design of dynamic model, which is used for simulation of designed systems. Final system will be used in Formule Student monopost.

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Urakubo, Takateru. "Control of Dynamical Systems with Kinematic Constraints." 京都大学 (Kyoto University), 2001. http://hdl.handle.net/2433/150262.

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Dresig, Hans, and Iosif I. Vul'fson. "Dynamik der Mechanismen." Universitätsbibliothek Chemnitz, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-201001121.

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Quadrelli, Bruno Marco. "Dynamic analysis of multi-flexible body systems with spatial beams and finite rotations." Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/12052.

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Torabi, Abbas. "An investigation of the kinetics and excited state dynamics of the nitrate free radical." Diss., Georgia Institute of Technology, 1985. http://hdl.handle.net/1853/28024.

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Zecha, Dan [Verfasser], and Rainer [Akademischer Betreuer] Lienhart. "Motion Kinematics and Dynamics Prediction Using Human Pose Estimation in Videos - Towards Automated, Kinematical Profiling of Swimmers and Ski Jumpers / Dan Zecha ; Betreuer: Rainer Lienhart." Augsburg : Universität Augsburg, 2020. http://d-nb.info/1215500424/34.

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Stellman, Paul Steven. "Kinematic and dynamic modeling of Nanostructured Origami." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/35639.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006.
Includes bibliographical references (leaves 85-88).
Nanostructured Origami is a manufacturing process that folds nanopatterned thin films into a desired 3D shape. This process extends the properties of 3D design and connectivity found in origami artwork to the bulk fabrication of 3D nanostructures. Our technique is a two-step procedure that first patterns the devices in 2D and then folds the membranes to the final 3D shape along pre-defined creases. This thesis describes theoretical methods that have been developed to model the actuation of origami devices. The background of origami mathematics and advances in robotics are presented in the context of modeling Nanostructured Origami. Unfolding of single-vertex origami is discussed, and an algorithm is implemented to calculate the unfolding trajectories of several devices. Another contribution of this thesis is the presentation of a methodology for modeling the dynamics of two classes of origami: accordion origamis and single-vertex origamis. The forward dynamics and equilibrium analysis of a useful bridge structure and the corner cube origami are simulated. The response of a model of an experimental actuation technique is well-behaved, and it is shown that the final folded state of these devices is at a stable equilibrium.
by Paul Steven Stellman.
S.M.

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Wiens, Alexander Joshua. "Slender elastic swimmers : kinematics, dynamics, and robotic applications." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/120198.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2018.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (pages 143-151).
Fish present a natural source of inspiration for the design of high-performance under-water robots. Conventionally, fish-like robotic systems consist of a chain of rigid links connected by a series of rigid actuators. Devices of this nature have demonstrated impressive speeds and maneuverability, but from a practical perspective, their mechanical complexity can make them expensive to build and prone to failure. One possible solution is to replace the mechanical body of the swimmer with a passive elastic element. In this scenario, the robot uses a single actuator, housed within a rigid forebody, to generate a fish-like propagating wave along a flexible trailing tail. A number of groups have explored this approach, but so far, these devices have demonstrated relatively limited performance. Here, we study the kinematics and dynamics of elastic swimmers and apply the results of this process to guide the design and testing of a high-performance passive robotic swimmer. We begin the investigation with a first-principles approach. We use analytical models of fish hydrodynamics to characterize the kinematics of efficient propulsion in swimming animals. Armed with the insight developed through this process, we construct a numerical model of a passive elastic swimming sheet. Through the application of optimization methods, we demonstrate that the sheet can achieve 70-80% of the efficiency of an equivalent swimmer with actuators along its entire body. Based on this, we design, build, and test a passive elastic swimming robot which uses a novel inertia-based actuation system. Experiments with the robot show that it can achieve a top speed of 1m/s (3.17 body lengths/s) and a peak turning rate of 515 deg/s, among the highest reported to date, while swimming at efficiencies comparable to those of fully actuated systems.
by Alexander Joshua Wiens.
Ph. D.

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Balaji, Kamalakkannan Balaji. "Modelling and Simulation of Vehicle Kinematics and Dynamics." Thesis, Högskolan i Halmstad, Halmstad Embedded and Intelligent Systems Research (EIS), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-34363.

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With the rapid growth in the automotive industry, vehicles have become more complex and sophisticated. Vehicle development today, involves integration of both electrical and mechanical systems. Their design and production are typically time and cost critical. To complement and support the process of vehicle development and design, majority of the automotive industry use modelling and simulationfor testing automotive applications, vehicle subsystems or the vehicle behaviour in its entirety. For the purpose of traffic simulations, where a large number of vehicles and other elements of the road network are simulated, implementing a highly complex vehicle model would greatly affect the performance of the simulation. The complexity of the vehicle model would entail a higher computation time of the system, making it unsuitable for any real time application. There in lies the trade-off indesigning a model that is both fast and accurate. The majority of the vehicle models that have been designed are either domain specific, highly complex or generalized. Thus, in this thesis, two class specific vehicles’ kinematic models with good accuracy and low computation time are presented. Two different modelling paradigms have been adopted to design and test these models. The results, challenges and limitations that pertain to these paradigms are also presented and discussed. The results show the feasibility of the proposed kinematic models.

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Skog, Erik. "Digital dynamisk geometrisäkring : En kartläggning av dagens arbetssätt." Thesis, Linköpings universitet, Maskinkonstruktion, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-97698.

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Detta examensarbete innehåller en kartläggning av Scanias arbete med digital dynamisk geometrisäkring samt ett förslag på hur arbetet kan utvecklas. Kartläggningen skapar en översiktlig bild av hur dagens arbete utförs och beskriver de ingående delmomenten. Observationer av hur arbetet utförs har gjorts och dokumenterats och samtal med berörda personer på Scania har skapat förståelse för behovet av ett bättre och mer utvecklat arbetssätt. Scania vill bli bättre på digital dynamisk geometrisäkring för att kunna minska den idag relativt stora verksamheten med fysisk provning av prototypartiklar och färdiga bilar. Ett förslag till ett nytt arbetssätt har tagits fram och förutsättningar för detta har undersökts på företaget. Förslaget bygger på ett ökat samarbete mellan grupper med olika ansvarsområden kopplade till vilka krav som ställs på lastbilen. Utöver den rent organisatoriska delen innefattar det även mer handgripliga förslag på fortsatt arbete som bland annat behöver ett underlag i form av trovärdiga simuleringsmodeller. En jämförelse mellan resultaten från dagens simulering och fysisk provning har genomförts och resultatet visar att vidare arbete med förbättring av de digitala modellerna krävs innan det nya arbetssättet kan anammas tillfullo.
This master thesis includes a mapping of Scania’s digital dynamic geometry assurance work and a suggestion on how to improve it. The mapping shows an overview of today’s working method and describes the included subsections. Observations of how today’s work is carried out have been done and documented and discussions with concerned people at Scania have built up understanding of the need of a better and more evolved working method. Scania want to get better at digital dynamic geometry assurance to be able to reduce the relatively big activity with physical testing of prototype articles and finished trucks. A suggestion for a new working method has been produced and the prerequisites for this method have been investigated at Scania. The suggestion is based on increased cooperation between groups with different responsibilities related to the demands placed on the truck. In addition to the purely organizational part, it also includes more hands-on suggestions for further work that among other things need a good foundation of trustworthy simulation models. A comparison of the results from today’s simulations and physical testing have showed that further work with improving the digital models is required to be able to adopt the new working method fully.

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Khan, Waseem A. "Distributed dynamics of systems with closed kinematic chains." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=79237.

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The simulation of mathematical models of mechanical systems with closed kinematic chains involves the solution to a system of highly coupled differential-algebraic equations. The numerical stiffness of these systems calls for small time steps in order to insure accuracy. Real-time and interactive forward simulations tend to be difficult to achieve for such systems, especially for large multi-body systems with multiple links and many kinematic loops. One way to overcome the time constraint is to distribute the load onto several processors.
The modular formulation of mathematical models is attractive because existing models may be assembled to create different topologies, e.g. cooperative robotic systems. Conversely, a given robotic topology may be broken into smaller topologies with simpler dynamics.
Moreover, parallel-kinematics machines bear inherent spatial parallelism. This feature is exploited in this thesis, in which we examine the formulation of such modular and distributed models and evaluate their performance as applied to mechanical systems with closed kinematic chains. Three general undistributed formulation methods are specialized to cope with distribution and modularity and applied to a three-degree-of-freedom planar parallel manipulator to generate distributed dynamics models.
Finally, the results of case studies are reported, and a comparison is made to highlight the salient features of each method.

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Rahgoshay, Cyril. "Editing and constraining kinematic approximations of dynamic motion." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=107891.

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This thesis presents inverse kinodynamics (IKD), an animator friendly kinematicworkflow that both encapsulates short-lived dynamics and allows precise space-timeconstraints. Kinodynamics (KD), defines the system state at any given time asthe result of a kinematic state in the recent past, physically simulated over a shorttemporal window to the present. KD is a well suited kinematic approximation to animatedcharacters and other dynamic systems with dominant kinematic motion andshort-lived dynamics. Given a dynamic system, we first formulate an appropriatekinodynamic window size based on kinematically defined accelerations in the kinematictrajectory and physical properties of the system. We then present an inversekinodynamics (IKD) algorithm, where a kinodynamic system can precisely attain aset of animator constraints at specified times. Our approach solves the IKD problemiteratively, and is able to handle full pose or end effector constraints at both positionand velocity level, as well as multiple constraints in close temporal proximity.Our approach can also be used to solve position and velocity constraints on passivesystems attached to kinematically driven bodies. We show IKD to be a compellingapproach to the direct kinematic control of character, with secondary dynamics viaexamples of skeletal dynamics and facial animation.
Cette thèse présente kinodynamique inversé (IKD) qui est un procédé kinematiquetrès pratique utilisable pour l'animateur qui consiste à la fois d'une dynamiquede courte durée et qui permet des contraintes spatio-temporelles précises. Kinodynamique (KD) définit l'état du système à un moment donné comme le résultat d'un état kinematique dans un passé récent, physiquement simulé dans une fenêtre temporelle de courte durée du temps présent. KD est une approximation kinematiquebien adaptée aux caractères animés et à d'autres systèmes dynamiques avec unmouvement kinematique dominant et une dynamique de courte durée. En ayant unsystème dynamique on peut d'abord formuler une taille de fenêtre kinodynamiqueappropriée, basée sur des accélérations définies kinematiquement dans la trajectoirekinematique et sur les propriétés physiques du système. Nous présentons ensuiteun algorithme kinodynamique inversé (IKD) dans lequel un système kinodynamiquepeut satisfaire un ensemble de contraintes des animateurs à des moments précis.Notre approche résout le problème IKD de manière itérative et permet de gérer unepose complète ou des contraintes des points fixés sur le corps à la fois au niveaude la position et de la vitesse ainsi que de multiples contraintes dans une courteproximité temporelle. Notre approche peut également être utilisée pour résoudredes contraintes de position et de vitesse dans des systèmes passifs attachés à descorps kinematiquement entrainés. Nous démontrons qu'IKD peut être une approcheconvaincante pour le contrôle kinematique direct des caractères avec des dynamiquessecondaires par des exemples de dynamiques du squelette et d'animation faciale.

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Lipfert, Susanne W. "Kinematic and dynamic similarities between walking and running." Hamburg Kovač, 2010. http://d-nb.info/100174232X/04.

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Howard, Colin Bryan. "Kinematic and dynamic modelling of foreland basin development." Thesis, University of Liverpool, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333687.

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Lee, Changyeol. "Compressible Convection and Subduction: Kinematic and Dynamic Modeling." Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/29260.

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Subduction is a dynamic and time-dependent process which requires time-dependent models for its study. In addition, due to the very high pressures within the Earthâ s interior, an evaluation of the role of compressibility in subduction studies should be undertaken. However, most subduction studies have been conducted by using kinematic, steady-state, and/or incompressible mantle convection models; these simplifications may miss important elements of the subduction process. In this dissertation, I evaluate the effects of time-dependence and compressibility on the evolution of subduction by using 2-D Cartesian numerical models. The effect of compressibility on the thermal and flow structures of subduction zones is evaluated by using kinematically prescribed slab and steady-state models. The effect of compressibility is primarily expressed as an additional heat source created by viscous dissipation. The heat results in thinner thermal boundary layer on the subducting slab and increases slab temperatures. With that exception, the effect of compressibility is relatively small compared with, for example, the effect of the mantle rheology on the thermal and flow structures of the mantle wedge. Plate reconstruction models show that the convergence rate and age of the incoming plate to trench vary with time, which poses a problem for steady-state subduction models. Thus, I consider the time-dependent convergence rate and age of the incoming plate in the kinematic-dynamic subduction models in order to understand the localization of high-Mg# andesites in the western Aleutians. The results show that the localization of high-Mg# andesites is a consequence of the time-dependent convergence rate and slab age along the Aleutian arc. The influence of mantle and slab parameters as well as compressibility on the slab dynamics is evaluated by using 2-D dynamic subduction models. The results demonstrate that periodic slab buckling in the mantle results in periodic convergence rate and dip of the subducting slab; time-dependence is a natural expression of subduction. The effect of compressibility on the slab dynamics is not significant. The periodic convergence rate and dip of the subducting slab explain time-dependent seafloor spreading at the mid-ocean ridge, convergence rate of the oceanic plate at trench and arc-normal migration of arc volcanoes.
Ph. D.

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Cheung, Wing-fung Jacob. "Kinematics, dynamics and control of high precision parallel manipulators." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B37907116.

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Cheung, Wing-fung Jacob, and 張穎鋒. "Kinematics, dynamics and control of high precision parallel manipulators." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B37907116.

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Kruger, Sarah E. "A dynamical systems investigation of loaded jump squat kinematics." Virtual Press, 2005. http://liblink.bsu.edu/uhtbin/catkey/1314334.

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The purpose of this project was to assess the coordination and performance of the jump squat movement for multiple loading conditions. Seventeen male subjects between 18 and 30 years of age, performed two jump squats for each loading condition, 0-60% of their one repetition maximum (1 RM) incremented by 10% for each trial. Video capture was used to assess kinematics and a force platform in combination with a linear position transducer was used to determine power. All of the peak power values occurred between 0% and 30% of 1 RM and there was an overall linear decrease in power output from 0-60% (p = 0.000). The shank-thigh and thigh-trunk mean absolute relative phase (MARP) values were shown to have linear increases from 0-60%, with p-values of 0.003 and 0.014 respectively. The MARP values calculated from 0-30% were significantly different than those at 60% for both segmental relationships. These results indicate that optimal jump squat performance occurs from 0-30% of 1 RM.
School of Physical Education, Sport, and Exercise Science

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Murray, Ingram Andrew. "Determining upper limb kinematics and dynamics during everyday tasks." Thesis, University of Newcastle Upon Tyne, 1999. http://hdl.handle.net/10443/185.

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In planning orthopaedic procedures or designing joint replacements for the upper limb, detailed knowledge on the kinematic and dynamic behaviour of the shoulder, elbow and wrist joints during the performance of everyday tasks is essential. Previous studies have included kinematic analyses of everyday activities involved in feeding and personal hygiene though none have included both the kinematic and dynamic analyses of these tasks. This study has involved the development, validation and application of experimental methods and analysis techniques, enabling the measurement and modelling of upper limb kinematics and dynamics. A four camera video-based motion analysis system was used to track reflective spheres attached at specific locations on the upper limb and trunk. Novel methods for the definition of the embedded trunk frame and glenohumeral rotation centre were incorporated. Joint attitudes, cadences, angular velocities and angular accelerations were calculated prior to the determination of external forces and moments through the dynamic modelling of the upper limb. The procedures developed have been validated against known measurements and the results of previous studies. These have been applied to obtain kinematic and dynamic data from unimpaired subjects and subjects with shoulder impairment during performance of ten everyday tasks involved in feeding, personal hygiene and the use of everyday objects. Elbow and shoulder flexion were found to be the primary components for the successful completion of the selected tasks. Reaching to the opposite side of the neck was identified as being the most complex of the activities tested in terms of rotation at the shoulder and elbow. Characteristic patterns of motion at the joints of the upper limb were identified during anterior targeted lifting. Differences in performance between the unimpaired and impaired subjects were identified, particularly in the results for cadence and the individual joint velocities and accelerations.

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Burton, Lisa Janelle. "The dynamics and kinematics of bio-in swimming systems." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/81692.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2013.
Cataloged from PDF version of thesis. Page 168 blank.
Includes bibliographical references (p. 155-167).
The motion of biological systems in fluids is inherently complex, even for the simplest organisms. In this thesis, we develop methods of analyzing locomotion of both mechanical and biological systems with the aim of rationalizing biology and informing robotic design. We begin by building on existing visualization framework by studying an idealized swimmer: Purcell's three-link swimmer, at low Reynolds number. This framework allows us to illustrate the complete dynamics of the system, design gaits for motion planning and identify optimal gaits in terms of efficiency and speed. We extend the three-link swimmer case to include effects such as the interaction between the links. By studying several systems, we broaden the applicability of our framework. These systems include a two-link swimmer at low Reynolds number with offset centers of buoyancy and mass and a swimmer with a continuously deformable shape, the serpenoid swimmer. Drawing on the principles behind the serpenoid swimmer, we develop the kinematic decomposition, a method using a singular value decomposition (SVD) that describes the motion of complex systems in a low order manner. We show that with only two degrees of freedom, one can adequately describe an animal's motion. We apply this method to species in both high and low Reynolds number environments to elucidate different phenomena, including chemotaxing and species comparison in spermatozoa, gait changes in eels (steady versus accelerating), kinematic responses to viscosity and viscoelasticity in C. elegans (nematodes), and the Kirmin gait in trout. Combined with our visualization framework, we successfully illustrate the generalized utility of the kinematic decomposition method to explore and understand fundamental kinematics of a wide range of both natural and man-made systems.
by Lisa Janelle Burton.
Ph.D.

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Garami, Boris. "Dynamický model harmonické převodovky." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2016. http://www.nusl.cz/ntk/nusl-254390.

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This thesis deals with the design of a dynamic model of a harmonic drive. It includes a theoretical study aimed at the analysis of the harmonic drive gearing principle and its nonlinear properties. The first part of the practical section deals with the analytical calculation of the nondeformed geometry of the Flexspline. Based on these results, several simulations in ANSYS are created to identify torsional characteristics of a harmonic drive. These simulation models are further enhanced by the analysis of clearance, backlash and inaccuracies and their impact on torsional properties. By using MATLAB /Simulink, several dynamic submodels are created representing the individual characteristics of nonlinearities in harmonic drives. Furthermore, a comprehensive dynamic model is created of the mechatronic system which is describing all nonlinearities and kinematic error of the transmission. The dynamic model is also experimentally verified based on its damping properties.

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Potent, Susanne. "Kinematik und Dynamik neogener Deformationsprozesse des südzentralchilenischen Subduktionssystems, nördlichste Patagonische Anden (37-̊40S̊)." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=969985487.

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Frame, Jeffrey W. "Kinetic and kinematic effects of altering cleat placement during cycling." Virtual Press, 2005. http://liblink.bsu.edu/uhtbin/catkey/1314325.

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One of the most important aspects of high performance cycling is the best fit between rider and bike. Developing a proper bike fit requires conducting many biomechanical assessments due to the need to match a myriad of bike geometries and human anthropometric variables. One of the primary bike-rider system measurement parameters for power and pedal efficiencies is the cleat placement and alignment. The purpose of this study was to examine the effects of moving the cleats towards the heel on peak power outputs and pedal efficiencies using a Computrainer (CT) and 2D video analysis. Ten competitive male cyclists participated in the study consisting of tests for peak power (PP) outputs and pedaling efficiencies among two positions of cleats; toe (TP) and heel (HP). No significant differences in peak power outputs were reported between TP and HP (p = .827). Significant differences (p = .027) did exist, however between each condition within the SpinScan (SS) pedal efficiency test. Results from the 2-D video analysis indicate that there exists a difference in ankling patterns between the TP and HP during the first 50 percent of the power phase and the last 50 percent of the recovery phase of the pedal stroke (p = .000 and .001 respectively Based on the results of this study, further research into the longitudinal effects of training in this area are warranted.
School of Physical Education, Sport, and Exercise Science

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Liu, Yu Gang. "Kinematics, dynamics and intelligent control for nonholonomic mobile modular manipulators." Thesis, University of Macau, 2006. http://umaclib3.umac.mo/record=b1636567.

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Layeghi, Kamran. "Kinematics and dynamics simulation control of a five-axis robot." Thesis, Keele University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277928.

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Famaey, Benoît. "Kinematics and dynamics pf giant stars in the solar neighbourhood." Doctoral thesis, Universite Libre de Bruxelles, 2004. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211090.

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We study the motion of giant stars in the Solar neighbourhood and what they tell us about the dynamics of the Galaxy: we thus contribute to the huge project of understanding the structure and evolution of the Galaxy as a whole.

We present a kinematic analysis of 5952 K and 739 M giant stars which includes for the first time radial velocity data from an important survey performed with the CORAVEL spectrovelocimeter at the Observatoire de Haute Provence. Parallaxes from the Hipparcos catalogue and proper motions from the Tycho-2 catalogue are also used.

A maximum-likelihood method, based on a bayesian approach, is applied to the data, in order to make full use of all the available stars, and to derive the kinematic properties of the subgroups forming a rich small-scale structure in velocity space. Isochrones in the Hertzsprung-Russell diagram reveal a very wide range of ages for stars belonging to these subgroups, which are thus most probably related to the dynamical perturbation by transient spiral waves rather than to cluster remnants. A possible explanation for the presence of young group/clusters in the same area of velocity space is that they have been put there by the spiral wave associated with their formation, while the kinematics of the older stars of our sample has also been disturbed by the same wave. The emerging picture is thus one of "dynamical streams" pervading the Solar neighbourhood and travelling in the Galaxy with a similar spatial velocity. The term "dynamical stream" is more appropriate than the traditional term "supercluster" since it involves stars of different ages, not born at the same place nor at the same time. We then discuss, in the light of our results, the validity of older evaluations of the Solar motion in the Galaxy.

We finally argue that dynamical modeling is essential for a better understanding of the physics hiding behind the observed kinematics. An accurate axisymmetric model of the Galaxy is a necessary starting point in order to understand the true effects of non-axisymmetric perturbations such as spiral waves. To establish such a model, we develop new galactic potentials that fit some fundamental parameters of the Milky Way. We also develop new component distribution functions that depend on three analytic integrals of the motion and that can represent realistic stellar disks.
Doctorat en sciences, Spécialisation physique
info:eu-repo/semantics/nonPublished

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Yin, KangKang. "Data-driven kinematic and dynamic models for character animation." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/31759.

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Human motion plays a key role in the production of films, video games, virtual reality applications, and the control of humanoid robots. Unfortunately, it is hard to generate high quality human motion for character animation either manually or algorithmically. As a result, approaches based on motion capture data have become a central focus of character animation research in recent years. We observe three principal weaknesses in previous work using data-driven approaches for modelling human motion. First, basic balance behaviours and locomotion tasks are currently not well modelled. Second, the ability to produce high quality motion that is responsive to its environment is limited. Third, knowledge about human motor control is not well utilized. This thesis develops several techniques to generalize motion capture character animations to balance and respond. We focus on balance and locomotion tasks, with an emphasis on responding to disturbances, user interaction, and motor control integration. For this purpose, we investigate both kinematic and dynamic models. Kinematic models are intuitive and fast to construct, but have narrow generality, and thus require more data. A novel performance-driven animation interface to a motion database is developed, which allows a user to use foot pressure to control an avatar to balance in place, punch, kick, and step. We also present a virtual avatar that can respond to pushes, with the aid of a motion database of push responses. Consideration is given to dynamics using motion selection and adaption. Dynamic modelling using forward dynamics simulations requires solving difficult problems related to motor control, but permits wider generalization from given motion data. We first present a simple neuromuscular model that decomposes joint torques into feedforward and low-gain feedback components, and can deal with small perturbations that are assumed not to affect balance. To cope with large perturbations we develop explicit balance recovery strategies for a standing character that is pushed in any direction. Lastly, we present a simple continuous balance feedback mechanism that enables the control of a large variety of locomotion gaits for bipeds. Different locomotion tasks, including walking, running, and skipping, are constructed either manually or from motion capture examples. Feedforward torques can be learned from the feedback components, emulating a biological motor learning process that leads to more stable and natural motions with low gains. The results of this thesis demonstrate the potential of a new generation of more sophisticated kinematic and dynamic models of human motion.
Science, Faculty of
Computer Science, Department of
Graduate

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Cabral, Ana Isabel Duarte. "Kinematics and physical properties of young proto-clusters." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/kinematics-and-physical-properties-of-young-protoclusters(8eb34d15-b343-4aab-b4b0-ede4bba903be).html.

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The formation of stars begins with the fragmentation of molecular clouds and the formation of dense cores. This fragmentation process can either be the result of classical gravitational instabilities or triggered by some external event. The gas and dust of young protoclusters often hold the imprints of the initial conditions and triggers of that specific star forming episode. In this context, my thesis work is a study of the gas properties of young protoclus- ters within the Gould Belt. The first part of my work consists of a detailed study of the young Serpens star forming region with CO isotopologues. This study has revealed a complex temperature, column density and velocity structure. I proposed a scenario where a collision between two filamentary clouds or flows is responsible for the observed complex structure and the most recent burst of star formation in Serpens. This hypothesis was tested with SPH simulations and provides a plausible scenario. I am currently extending this work to other regions with a variety of star formation efficiencies, in search of the particular physical properties and dynamics of a molecular cloud that allow or prevent clouds to be in the verge of forming stars. As such, I have included in this manuscript my study of the gas in the B59 star forming region, the only active clump in the Pipe Nebula. The results from this study have shown it to be very different from Serpens, even though further studies are needed to provide a complete picture of the region. B59 was taken as the starting point for a larger study of the entire Pipe Nebula, driven by the peculiarly low star formation efficiency in the cloud and a test to the physical properties of cores prior to star formation.

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Bremer, Florian Heinrich. "Karoo rifting im Morondava Becken, Madagaskar: fazielle Entwicklung, Kinematik und Dynamik eines polyphasen Riftbeckens." [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=975019910.

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Bruni, Danilo <1978&gt. "Intraoperative kinematic evaluation with navigation system and postoperative kinematic evaluation with dynamic RSA of total knee arthroplasty." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6450/.

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Restoring a correct implant kinematics and providing a good ligament balance and patellar tracking is mandatory to improve clinical and functional outcome after a Total Knee Replacement. Surgical navigation systems are a reliable and accurate tool to help the surgeon in achieving these goals. The aim of the present study was to use navigation system with an intra-operative surgical protocol to evaluate and determine an optimal implant kinematics during a Total Knee Replacement.

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Fattah, Abbas. "Dynamics of robotic manipulators with flexible links and kinematic loops." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=28740.

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The necessity of modelling multibody systems with flexible links in high-speed operations and space structures has become apparent. In this thesis, a general formulation for the simulation of multibody systems with multiple kinematic loops and flexible links of arbitrary shapes is developed. Parallel manipulators, space structures, multi-armed manipulators, and cooperating serial manipulators are examples of these systems.
Finite element method is used for discretization of the flexible links, while the Lagrange formulation is used to derive the equations of motion of the uncoupled links. The kinematic constraints equations are generated next by using the natural orthogonal complement (NOC) of the twist-constraint matrix. Here, the formulation of the problem is obtained both in joint and in Cartesian spaces. Using the NOC, the constraint forces are eliminated from the equations of motion to obtain the governing equations of the system in minimum coordinates. Moreover, the formulation incorporates geometric nonlinearities in the elastic displacements, which can be very crucial in large rigid-body motions.
A simulation environment is developed to perform the procedures underlying the above formulations for different types of robotic manipulators with kinematic loops and flexible links. To highlight the link flexibility effect, the governing equations of motion are used in the simulation of the aforementioned systems to compare the results obtained with the rigid and the flexible-link models.

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Stoenescu, Eleonor D. Marghitu Dan B. "Dynamics and synthesis of kinematic chains with impact and clearance." Auburn, Ala., 2005. http://repo.lib.auburn.edu/EtdRoot/2005/SPRING/Mechanical_Engineering/Dissertation/STOENESCU_ELEONOR_32.pdf.

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Simons, Raymond C., Susan A. Kassin, Jonathan R. Trump, Benjamin J. Weiner, Timothy M. Heckman, Guillermo Barro, David C. Koo, et al. "KINEMATIC DOWNSIZING AT z similar to 2." IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/624072.

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We present results from a survey of the internal kinematics of 49 star-forming galaxies at z similar to 2 in the CANDELS fields with the Keck/MOSFIRE spectrograph, Survey in the near-Infrared of Galaxies with Multiple position Angles (SIGMA). Kinematics (rotation velocity V-rot and gas velocity dispersion sg) are measured from nebular emission lines which trace the hot ionized gas surrounding star-forming regions. We find that by z similar to 2, massive star-forming galaxies (log M-*/M-circle dot less than or similar to 10.2) have assembled primitive disks: their kinematics are dominated by rotation, they are consistent with a marginally stable disk model, and they form a Tully-Fisher relation. These massive galaxies have values of V-rot sg that are factors of 2-5 lower than local well-ordered galaxies at similar masses. Such results are consistent with findings by other studies. We find that low-mass galaxies (log M-*/M-circle dot less than or similar to 10.2) at this epoch are still in the early stages of disk assembly: their kinematics are often dominated by gas velocity dispersion and they fall from the Tully-Fisher relation to significantly low values of V-rot. This "kinematic downsizing" implies that the process(es) responsible for disrupting disks at z similar to 2 have a stronger effect and/or are more active in low-mass systems. In conclusion, we find that the period of rapid stellar mass growth at z similar to 2 is coincident with the nascent assembly of low-mass disks and the assembly and settling of high-mass disks.

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Henault-Brunet, Vincent. "Massive binary stars and the kinematics of Young Massive Clusters." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/8047.

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Located in the Large Magellanic Cloud, R136 is a rare example of a nearby young and dense massive star cluster in which individual stars can be resolved. Often suggested as a globular cluster in formation, its study is of great interest and promises to provide insights into the early dynamical evolution of massive star clusters. This is crucial to understand more extreme and distant starburst clusters, which contribute to a significant fraction of all current star formation in the Local Universe, in particular in interacting galaxies. The majority of this thesis is based on multi-epoch spectroscopic observations in and around R136 obtained as part of the VLT-FLAMES Tarantula Survey (VFTS), an ambitious programme which targeted nearly 1 000 massive stars in the intricate 30 Doradus star-forming region. The motivations and observing strategy of this survey, designed to address key questions about the evolution of massive stars and clusters, are first introduced. The data reduction procedures applied to VFTS data are described, with an emphasis on the tasks accomplished in the context of this thesis. The VFTS data are first used to perform a detailed kinematic study of R136, determine its dynamical state, and evaluate the importance of gas expulsion in the early evolution of massive star clusters. Orbital motions of binary stars are found to dominate the line- of-sight velocity dispersion of the cluster, illustrating the risk of interpreting velocity dispersion measurements for unresolved extragalactic young massive clusters. However, once the detected binaries are rejected and the contribution of undetected binaries is accounted for through Monte Carlo simulations, the true velocity dispersion of the cluster is found to be low and consistent with it being in virial equilibrium. This suggests that gas expulsion has not had a dramatic effect on the early dynamical evolution of R136. Using the velocity measurements of R136 as a test case, a maximum likelihood method that fits the velocity dispersion of a cluster from a single epoch of radial velocity data is then tested. The method must be applied with care given the high binary fraction of massive stars and the large uncertainties in their binary orbital parameter distributions, but for typical velocity dispersions of young massive clusters (& 4 kms−1), it is shown that the velocity dispersion can be measured with an accuracy of 40% or better. This offers an efficient way of constraining the dynamics of these systems. The radial velocity measurements of apparently single stars in R136 are also used to investigate the internal rotation of the cluster, a potentially important but largely unexplored characteristic of young clusters. Evidence is found, at the 95% confidence level, for rotation of the cluster as a whole. A simple maximum likelihood method is presented to fit rotation curves to the data, from which a typical rotational velocity of 3 kms−1 is found. When compared to the low velocity dispersion of R136, this suggests that star clusters may form with as much as 20% of their kinetic energy in rotation. Finally, a smaller-scale survey of massive stars in the Wing of the Small Magellanic Cloud is introduced. As an example of the particularly interesting massive binaries that can be revealed by the synergy between large optical spectroscopic surveys of young clusters and observations at other wavelengths, the discovery of a new Be/X-ray pulsar binary and associated supernova remnant is reported. With a long spin period of over 1 000 seconds and a young age of 104 years constrained by its association with the supernova remnant, the pulsar in this system is quickly emerging as a unique object that challenges our understanding of the spin evolution of accreting neutron stars.

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Dissertations / Theses on the topic 'Kinematika a dynamika'

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