Academic literature on the topic 'Pendulum movement'
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Journal articles on the topic "Pendulum movement"
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Soans, Crystal Runa, Ashutosh Shetty, Murali P.S, Azhar Mohammed, U. S. Krishna Nayak, and Keerthan Shashidhar. "Comparative Distalization Effects Of Conventional Pendulum Appliance And Bone Anchored Pendulum Appliance." Journal of Health and Allied Sciences NU 08, no. 01 (March 2018): 03–010. http://dx.doi.org/10.1055/s-0040-1708737.
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Abstract Introduction: The introduction of intraosseous screws as temporary orthodontic anchorage devices has proved successful in achieving sufficient molar distalization without major anchorage loss in Class II malocclusions. Bone-anchored pendulum appliance is used to obtain an effective and compliance-free molar distalization without anchorage loss. Aims And Objectives: This prospective study was designed to evaluate and compare the skeletal and dentoalveolar effects produced by 2 types of pendulum appliance with different anchorage modalities - the Bone anchored pendulum appliance (BAPA) and Conventional pendulum appliance (CPA) in subjects with Angle's ClassII malocclusion. Materials and Methods: BAPA group consisted of 5 patients with mean age, 16.4±1.5 years. The CPA group consisted of 5 patients with mean age, 16.6±1.1 years. Lateral cephalograms & dental casts were obtained at pre-treatment stage & after achieving Class I molar relation. Dentoalveolar, skeletal, soft tissue measurements and dental cast measurement were recorded & compared between the groups. Results and Conclusions: Successful distalization was achieved in both groups in a mean period of 6.2 months for BAPA and 5.2 months for CPA. It was concluded that, both theBAPA and CPA were effective for the distalization of maxillary molars. Though the distal molar movements obtained were similar between the BAPA and the CPA groups, anchorage loss was observed with the CPA in the form of premolar mesialization & incisor proclination, whereas absence of anchorage loss, significant spontaneous distal premolar movement, and distal incisor movement was observed with the BAPA, making it a viable choice compared to the CPA.
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Bendersky, S., and B. Sandler. "Investigation of a spatial double pendulum: an engineering approach." Discrete Dynamics in Nature and Society 2006 (2006): 1–22. http://dx.doi.org/10.1155/ddns/2006/25193.
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The behavior of a spatial double pendulum (SDP), comprising two pendulums that swing in different planes, was investigated. Movement equations (i.e., mathematical model) were derived for this SDP, and oscillations of the system were computed and compared with experimental results. Matlab computer programs were used for solving the nonlinear differential equations by the Runge-Kutta method. Fourier transformation was used to obtain the frequency spectra for analyses of the oscillations of the two pendulums. Solutions for free oscillations of the pendulums and graphic descriptions of changes in the frequency spectra were used for the dynamic investigation of the pendulums for different initial conditions of motion. The value of the friction constant was estimated experimentally and incorporated into the equations of motion of the pendulums. This step facilitated the comparison between the computed and measured oscillations.
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Del Río-Cidoncha, Gloria, José Ignacio Rojas-Sola, and Francisco Javier González-Cabanes. "Computer-Aided Design and Kinematic Simulation of Huygens’s Pendulum Clock." Applied Sciences 10, no. 2 (January 10, 2020): 538. http://dx.doi.org/10.3390/app10020538.
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This article presents both the three-dimensional modelling of the isochronous pendulum clock and the simulation of its movement, as designed by the Dutch physicist, mathematician, and astronomer Christiaan Huygens, and published in 1673. This invention was chosen for this research not only due to the major technological advance that it represented as the first reliable meter of time, but also for its historical interest, since this timepiece embodied the theory of pendular movement enunciated by Huygens, which remains in force today. This 3D modelling is based on the information provided in the only plan of assembly found as an illustration in the book Horologium Oscillatorium, whereby each of its pieces has been sized and modelled, its final assembly has been carried out, and its operation has been correctly verified by means of CATIA V5 software. Likewise, the kinematic simulation of the pendulum has been carried out, following the approximation of the string by a simple chain of seven links as a composite pendulum. The results have demonstrated the exactitude of the clock.
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Levkova, E. A., S. Z. Savin, and N. E. Kosykh. "Studies of depressive spectrum disorders caused by sleep deprivation in conditions of chronic desynchronosis (analytical review)." Terapevt (General Physician), no. 12 (December 17, 2020): 50–55. http://dx.doi.org/10.33920/med-12-2012-06.
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This review examines fundamental approaches to studying the phenomena of pendulum-like chronic desynchronosis in conditions of multi-latitude movement without adaptation in extreme time zones. The article analyzes works on psychophysiological and chronobiological aspects of depressive disorders in the regime of multi-latitude pendulum-like movements in conditions of impossibility of biorhythmological adaptation at the limiting points of the flight. Effective proposals of means and measures for elimination of psychosomatic consequences of chronic desynchronosis and compensation of depressive spectrum disorders are presented.
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Kumagai, Masaaki, and Takaya Ochiai. "Development of a Robot Balanced on a Ball - First Report, Implementation of the Robot and Basic Control -." Journal of Robotics and Mechatronics 22, no. 3 (June 20, 2010): 348–55. http://dx.doi.org/10.20965/jrm.2010.p0348.
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This paper proposes the implementation and control scheme of a robot balanced on a ball. Unlike a twowheeled inverted pendulum, such as the Segway Human Transporter, an inverted pendulum using a ball moves in any direction without changing orientation, enabling isotropic movement and stabilization. The robot on the ball can be used in place of the twowheeled robots. Our robot has three omnidirectional wheels with stepping motors that drive the ball and two sets of rate gyroscopes and accelerometers as attitude sensors. It can keep station, traverse in any direction, and turn around its vertical axis. Inverted pendulum control is applied to two axes to maintain attitude. Ball acceleration is used as control input of the system, unlike most of inverted pendulums which use torque or force as input. This acceleration input makes the robot robust against change of inertia parameters, as confirmed by Nyquist diagrams. The mechanism of the robot, the control method, and the experimental results are described in this paper.
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Saigo, M., N. Tanaka, and K. Tani. "An Approach to Vibration Control of Multiple-Pendulum System by Wave Absorption." Journal of Vibration and Acoustics 120, no. 2 (April 1, 1998): 524–33. http://dx.doi.org/10.1115/1.2893861.
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In this paper, a new wave-absorbing strategy has been studied to suppress the vibration of a multiple-pendulum system by controlling the lateral movement of the support. The wave-absorbing condition is derived from the difference between the equation of motion of the boundary pendulum and that of an inner pendulum. An online real-time simulation method using the numerical solution is proposed to control the movement that satisfies the wave-absorbing condition. According to this method, vibration of a multiple-pendulum system with arbitrary degrees of freedom can be controlled by measuring only the deflection angle of the uppermost pendulum adjacent to the support if the dimensions of the uppermost pendulum and the total mass of the system are known. Both the numerical simulations and the experiments have confirmed the effectiveness of this method. The basic idea of this control method can easily be applied to any discrete vibrating system whose equations of motion have no traveling-wave solution.
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Teixeira, Julio Carlos, Pâmella Gonçalves Martins, Amanda Schwartzmann, and Jeroen Schoenmaker. "The Gauss pendulum." Emergent Scientist 5 (2021): 3. http://dx.doi.org/10.1051/emsci/2021002.
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Recently, the Gauss rifle has gained attention as an interesting problem for physics and engineering education. In this manuscript we propose and analyze a novel problem that, while being related to the Gauss rifle, is rather simpler: the Gauss pendulum, which yields more consistent results and allows further agreement between model, simulation and experimental data. The Gauss pendulum, unlike the rifle, does not involve rotational movement of balls and the difference between the initial and final energy state of the system can be easily accessed by measuring the final height of the swinging projected ball. An extensive assessment of a Gauss pendulum has been developed using free software and accessible laboratory equipment. Focusing on the validation of the magnetic potential well model to understand the gain in kinetic energy, it was possible to obtain a remarkable agreement between the experimental and theoretically simulated data.
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Qian, Qingwen, Junfeng Wu, and Zhe Wang. "Dynamic balance control of two-wheeled self-balancing pendulum robot based on adaptive machine learning." International Journal of Wavelets, Multiresolution and Information Processing 18, no. 01 (March 29, 2019): 1941002. http://dx.doi.org/10.1142/s0219691319410029.
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To solve the problem of balance control in dynamic movement of two-wheeled self-balancing pendulum robot, a dynamic balance control method based on adaptive machine learning is proposed based on theoretical analysis of the cause of balance. Firstly, a kinematics model of two-wheeled self-balancing pendulum robot is established. Through numerical calculation and analysis, the root cause for dynamic balance of two-wheeled self-balancing pendulum robot is obtained. On this base, adaptive machine learnings are proposed to control the dynamic balance of two-wheeled self-balancing pendulum robot. The possible lateral movement of robot caused by dynamic balance control is analyzed. Finally, balance simulation test is conducted, which shows that the robot can easily lose balance and overturn without adaptive machine learning. The comparison of simulation test has verified that the proposed dynamic balance control method can effectively control the dynamic balance of two-wheeled self-balancing pendulum robot.
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Sen, Muhammed Arif, and Mete Kalyoncu. "Optimisation of a PID Controller for an Inverted Pendulum Using the Bees Algorithm." Applied Mechanics and Materials 789-790 (September 2015): 1039–44. http://dx.doi.org/10.4028/www.scientific.net/amm.789-790.1039.
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The inverted pendulum system is a challenging control problem in the control theory, which continually moves away from a stable state. The paper presents the design of a Proportional-Integral-Derivative (PID) controller for a single-input multi-output (SIMO) inverted pendulum system and using the Bees Algorithm (BA) to obtain optimal gains for PID controllers. The Bees Algorithm optimizes the gains so that the controller can move the cart to a desired position with the minimum amount of the change in the pendulum’s angle from the vertically upright position during the movement. The tuning aim is to minimize the control responses of the cart’s position and the pendulum’s angle in time domain. MATLAB/Simulink simulation has been performed to demonstrate that the effects on the system performance of PID controllers with optimal gains. The obtained results show that the tuning method by using the Bees Algorithm produced PID controllers successfully within the controller design criteria. Following a description of the inverted pendulum system and the Bees Algorithm, the paper gives the obtained simulation results for the system demonstrating the efficiency of the design.
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Lisowski, Bartłomiej, Clement Retiere, José Pablo Garcia Moreno, and Paweł Olejnik. "Semiempirical identification of nonlinear dynamics of a two-degree-of-freedom real torsion pendulum with a nonuniform planar stick–slip friction and elastic barriers." Nonlinear Dynamics 100, no. 4 (May 15, 2020): 3215–34. http://dx.doi.org/10.1007/s11071-020-05684-6.
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Abstract The purpose of this study is to identify the nonlinear dynamics of the double torsion pendulum with planar friction and elastic barriers. The original experimental stand consists of a disk-shaped body that rotates freely on top of a forced column with a system of barriers limiting the torsional vibrations of the pendulum bodies that create an nonuniform planar rotational friction contact. Two beam springs form soft barriers modeled by Voigt elements that limit the angular displacement of one of the pendulum bodies—the disk, while the second limiting system, made of a much more rigid barrier, limits the movement of the pendulum’s second body. The dynamic behavior of the asymmetrical system of two degrees of freedom with discontinuities is identified with the use of the described strategy, numerical solutions of the derived mathematical model and the Nelder–Mead simplex algorithm. The actual measurement series and numerical solutions show a good similarity of the dynamical reaction of the mechanical system and its virtual analog.
Dissertations / Theses on the topic "Pendulum movement"
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Krapp, James Joseph. ""At the Still Point of the Turning World": A Reference to Time and Movement." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/31690.
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A Clinic for the study of Sleep Disorders
The proposal for a clinic for sleep disorders sited on the edge of Dupont Circle within the District of Columbia.
This thesis is a reference to time and movement as it relates to our individual perception. We each experience our environments differently and architecture should be prescribed to the fit the needs of the individual. It is the study of design
evolution along a time-line. The science of effect. As we move along a line how does our environment and influence shape the final outcome?
In architecture, process is the task of understanding. The following documentation is my personal time-line along that undefined path.Master of Architecture
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Swain, Ryan C. "Stability and control of a two-link inverrted pendulum system with application to human trunk movement during walking." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0007/MQ41636.pdf.
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Silva, Neide Honorato da. "Ferrovia e mobilidade intrametropolitana: um estudo sobre o movimento pendular no cotidiano dos trabalhadores do ABC paulista." Pontifícia Universidade Católica de São Paulo, 2016. https://tede2.pucsp.br/handle/handle/18915.
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This study aimed to evaluate the pendulum movement of ABC workers toward employers centers as an essential aspect of the reproduction of labor power in its broad inclusion in numerous tertiary in the metropolis of São Paulo. Seeks to characterize the intrametropolitan mobility and the problems of urban transport, focusing on metropolitan trains, identifying the diversity of its members and their difficulties on the way home to work. This study provides an understanding of the socio-spatial segregation process, evidenced in the long distances that separate the place of residence and place of work of the residents of the suburbs of Greater São Paulo. The implementation of the rail system in São Paulo had intimate relationships with coffee and favored the formation process of the metropolis. The São Paulo Railway was the first railway in the state of São Paulo, built in order to facilitate the transportation of coffee to the port of Santos. After going through several changes during the transition from the nineteenth to the twentieth century, today this railway is managed by CPTM (São Paulo Metropolitan Train Company), especially as part of the mobility and transport workers. Based on theoretical and methodological support consistent with the complexity of the subject, secondary data collection and statistical and field research, we believe present reflections indicative of the need for public policies that prioritize public transport
O presente estudo objetiva conhecer o movimento pendular no cotidiano dos trabalhadores do ABC paulista em direção aos centros empregadores, como aspecto essencial da reprodução da força de trabalho em sua ampla inserção no terciário numeroso na metrópole de São Paulo. Busca caracterizar a mobilidade intrametropolitana e a problemática do transporte coletivo, com foco nos trens metropolitanos, identificando a diversidade de seus usuários e suas dificuldades no trajeto casa-trabalho. Este estudo propicia a compreensão do processo de segregação sócio–espacial, evidenciado nas longas distâncias que separam o local de moradia e o local de trabalho dos moradores dos subúrbios da Região Metropolitana de São Paulo. A implantação do sistema ferroviário em São Paulo teve íntimas relações com a cafeicultura e favoreceu o processo de constituição da metrópole paulista. A São Paulo Railway foi a primeira estrada de ferro do estado de São Paulo, construída com o objetivo de facilitar o transporte do café até o porto de Santos. Após passar por várias transformações ao longo da transição do século XIX para o século XX, atualmente essa ferrovia é administrada pela CPTM (Companhia Paulista de Trens Metropolitanos), destacando-se como integrante das redes de mobilidade e transporte de trabalhadores. Com base em aporte teóricometodológico compatível à complexidade do tema, coleta de dados secundários e estatísticos e pesquisa de campo, acreditamos apresentar reflexões indicativas da necessidade de políticas públicas que priorizem os transportes coletivos
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Wenlöf, Emil. "Tracing Bolivia's Swing of the Pendulum : Tracing the process of popular resistance in Bolivia." Thesis, Linnéuniversitetet, Institutionen för samhällsstudier (SS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-100903.
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Policy regime shift through popular societal resistance in developing countries, advocating a state-regulated economic model, has been a frequent occurrence in the 21st century, during a period where neoliberalism has dominated the world market. Scholars have brought up the framework of double movement to explain these social, economic, and political changes from free-market regimes to state-controlled regimes, claiming that it is a societal reaction to the commodification of land, labor, and money. This research poses the question of how political change can be interpreted through the lens of the concept of double movement even though a government can show positive social and economic development records, where a left-wing state-regulated market has ruled the economy. Bolivia underwent political turmoil in 2019, where the former president Evo Morales, who had brought high socioeconomic development through a state-regulated economy, was ousted by a nationwide protest. An interim conservative government took office, imposing a harsh neoliberal agenda with authoritarian features, handing over the presidency to Morales’ former party only a year later, as the party won the election. Looking at the case of Bolivia through the lens of the double movement, this research found that commodification of land, labor, and money can explain popular societal resistance in Bolivia during Morales's presidency. However, the case also proved that commodification was not the only, and potentially not even the main, reason for the overthrow of Morales. Political motives and actions, clientelism, social cleavages, respect for democratic principles, and more theoretical perspectives need to be considered to comprehend regime change by popular resistance further.
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Fuschillo, Valeria Lucia <1981>. "From inverted pendulum to N-link chain: inertial sensors-based assessment of movement kinematics and dynamics for functional evaluation and rehabilitation." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5834/.
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Despite several clinical tests that have been developed to qualitatively describe complex motor tasks by functional testing, these methods often depend on clinicians' interpretation, experience and training, which make the assessment results inconsistent, without the precision required to objectively assess the effect of the rehabilitative intervention. A more detailed characterization is required to fully capture the various aspects of motor control and performance during complex movements of lower and upper limbs. The need for cost-effective and clinically applicable instrumented tests would enable quantitative assessment of performance on a subject-specific basis, overcoming the limitations due to the lack of objectiveness related to individual judgment, and possibly disclosing subtle alterations that are not clearly visible to the observer.
Postural motion measurements at additional locations, such as lower and upper limbs and trunk, may be necessary in order to obtain information about the inter-segmental coordination during different functional tests involved in clinical practice. With these considerations in mind, this Thesis aims: i) to suggest a novel quantitative assessment tool for the kinematics and dynamics evaluation of a multi-link kinematic chain during several functional motor tasks (i.e. squat, sit-to-stand, postural sway), using one single-axis accelerometer per segment, ii) to present a novel quantitative technique for the upper limb joint kinematics estimation, considering a 3-link kinematic chain during the Fugl-Meyer Motor Assessment and using one inertial measurement unit per segment.
The suggested methods could have several positive feedbacks from clinical practice. The use of objective biomechanical measurements, provided by inertial sensor-based technique, may help clinicians to: i) objectively track changes in motor ability, ii) provide timely feedback about the effectiveness of administered rehabilitation interventions, iii) enable intervention strategies to be modified or changed if found to be ineffective, and iv) speed up the experimental sessions when several subjects are asked to perform different functional tests.
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Stamm, Cristiano. "O fenômeno dos movimentos pendulares dos trabalhadores intermunicipais entre cidades de porte médio: o caso de Cascavel e Toledo (PR)." Universidade Estadual do Oeste do Parana, 2005. http://tede.unioeste.br:8080/tede/handle/tede/2234.
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The central objective of this work was to examine the phenomenon of pendulum movements between the medium size towns of Cascavel and Toledo, located in the West Mesoregion of the State of Paraná. The importance of studying the phenomenon of pendulum movements, specifically of the commuters, is due to the diffusion of the urban tendencies in the great centers and for the great potential that the phenomenon has in spreading out across the national territory and, fundamentally as a result of the growth of the medium towns in the country. First, the theoretical approaches about the urban subject were collected, mainly of the nets and urban hierarchies, as they are fundamental for the function of the urban movements. After that, some considerations about the internal migrations and pendulum movements were made. The methodological research prioritized two points: the analysis of literature and field research developed with the metropolitan bus passengers. For this purpose, it was adopted as criterion for the medium towns, the municipal districts with a population between one thousand to five thousand inhabitants in Brazil. In the results, a socioeconomic profile of the population that uses the metropolitan bus as means of transportation for the commuting between the towns of Cascavel and Toledo was drawn. It was possible to observe that 70,33% of the interviewees was employed and that the great majority (58,75%) had upper or secondary education levels. Another evidence was that 54.67% of the interviewed ones received up to 4 minimum wages as familiar income. Thus, the information related to the commuters to Cascavel-Toledo and Toledo-Cascavel were analyzed, indicating characteristics such as sex, age, education, wage, income, sector of occupation, expended average time in commuting and, also, the frequency of these movements. After the analysis of the commuters profile, it was observed that they presented economic factors, such as motivation, to commute and social factors as reasons for not to migrate to the cities they were working. Therefore, such data has evidenced some particular trends and specific uses of the metropolitan bus as an inter-municipal movement. It was confirmed the hypothesis that a flow of commuters between the medium provincial towns of Cascavel and Toledo, such as those presented by the urban trends in the great centers and in the metropolitan regions are occurring in small country towns.
O objetivo central desse trabalho foi examinar o fenômeno dos movimentos pendulares dos trabalhadores intermunicipais entre as cidades interioranas de porte médio de Cascavel e de Toledo, localizadas na Mesorregião Oeste do Estado do Paraná. A importância de se estudar o fenômeno dos movimentos pendulares, especificamente dos trabalhadores, se faz devido à difusão das tendências urbanas ocorridas nos grandes centros e pelo grande potencial que esse fenômeno tem em se alastrar pelo território nacional e, fundamentalmente, em razão do crescimento das cidades de porte médio no interior do país. Preliminarmente, foram levantadas as abordagens teóricas sobre a questão urbana, principalmente das redes e hierarquias urbanas, pois estas são fundamentais para a funcionabilidade dos movimentos urbanos. Logo após, foram feitas algumas considerações sobre as migrações internas e movimentos pendulares. A pesquisa metodológica priorizou dois pontos, os quais são: a análise da literatura disponível e a pesquisa de campo com os usuários do ônibus metropolitano na região estudada. Para tanto, se adotou como critério para as cidades de porte médio os municípios com uma população entre 100 mil e 500 mil habitantes no Brasil. Nos resultados foi traçado um perfil socioeconômico da população que utiliza o ônibus metropolitano como meio de transporte para o deslocamento intermunicipal entre as cidades de Cascavel e Toledo. Dessa forma, observou-se que 70,33% dos entrevistados estavam empregados e que a grande maioria (58,75%) apresentavam ter o ensino médio completo ou superior, como nível de escolaridade. Outra evidencia foi de que 54,67% dos entrevistados tinham uma faixa de até 4 salários mínimos como renda familiar. Em seguida foram analisadas as informações relacionadas aos trabalhadores pendulares nos sentidos Cascavel-Toledo e Toledo-Cascavel, indicando características, como sexo, idade, escolaridade, salário, renda salarial, setor de ocupação, tempo médio despendido no movimento pendular e, também, a freqüência desses movimentos. Após o perfil dos trabalhadores pendulares observou-se que esses apresentaram fatores econômicos como motivação para realizar tais movimentos e fatores sociais como motivos para não migrarem para as cidades que estavam trabalhando. Dessa forma, tais dados evidenciaram algumas tendências e particulares daqueles que utilizam o ônibus metropolitano como deslocamento intermunicipal. Confirmou-se a hipótese do trabalho de que está ocorrendo um fluxo de trabalhadores pendulares entre as cidades interioranas de porte médio de Cascavel e de Toledo, de tal forma que as tendências urbanas apresentadas nos grandes centros e nas regiões metropolitanas estão ocorrendo em cidades de menor porte populacional no interior do país.
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Peixoto, Christian Savelli de Lorena. "A biomecânica do tênis de campo e a sua prática otimizada." Universidade de São Paulo, 1999. http://www.teses.usp.br/teses/disponiveis/82/82131/tde-26102017-092122/.
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O movimento pendular é dotado de qualidades dinâmicas, estratégicas e biomecânicas que o tornam padrão de excelência para o ensino do tênis. Ele reduz em até uma ordem de grandeza o esforço físico dispendido e elimina os riscos de tendinites do tipo \"cotovelo de tenista\". Transfere, dentro da maior eficiência, o impulso do chão sobre os pés para os quadris, tórax, braço e raquete. Naturalmente mantém o braço esticado e o punho rígido. Maximiza a velocidade da raquete e minimiza a indicação de endereçamento da bola. Estes são as conclusões do presente trabalho, buscando-se uma comparação direta das qualidades do movimento pendular frente as práticas de movimentação difundidas atualmente para o tênis de campo. São utilizadas conceituações dinâmicas e biomecânicas simples, fundamentadas na anatomia das inserções musculares, dos centros de gravidade e de rotação dos segmentos do corpo envolvidos nos movimentos. Os resultado indicam um aumento de eficiência com a utilização da movimentação pendular, atingindo-se um ganho médio de 10% em velocidade da raquete com uma redução do impulso no solo de cerca de 20%.The pendular movement for the practice of optimized tennis has been under study as a graduate project at the Escola de Engenharia de São Carlos, Universidade de São Paulo-Brazil since 1977. The proposed procedure is based on the Newton\'s Laws of dynamics. The pendular movement incorporates dynamic, strategic, and biomechanical qualities that lends itself to a standard of excellence for tennis coaching. It reduces the dispended physical effort by one order of magnitude as well as eliminating the risk of tendinitis, among them the well known \"tennis elbow\". It also transfers the impulse received from the ground through the feet to the hip, torax, arm and raquet with the maximum efficiency. It keeps the arm naturally extended and the wrist rigid. It also maximizes the velocity of the raquet and reduces to a minimum the chances of the opponent anticipating the addressing of the ball. The characterisics of the pendular movement are compared to the other fundamental movements, the vertical, the rigid and the free movement. Simple dynamic and biomechanical concepts are utilized, based on the anatomy of muscular tendon insertions, on the centres of gravity and rotation of the body segments involved in the movement.
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Bonus, Alexander Evan. "The Metronomic Performance Practice: A History of Rhythm, Metronomes, and the Mechanization of Musicality." Case Western Reserve University School of Graduate Studies / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=case1270221548.
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Oliveira, Henrique Bianchi. "Mecânica e energética da caminhada de crianças obesas." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/128042.
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A obesidade é considerada atualmente como uma doença com proporções epidêmicas. O excesso de peso está relacionado com a falta de atividade física suficiente e tem sido diagnosticado, de forma crescente, desde a infância. Diversos fatores de risco estão ligados à obesidade, como diabetes tipo 2, hipertensão arterial, dislipidemias entre outros. A caminhada apresenta associação com a diminuição desses fatores de risco, além da melhora na saúde ortopédica e metabólica, principalmente em crianças e adolescentes obesos. Embora existam evidências sobre a marcha de adultos e adolescentes obesos, informações sobre a mecânica da marcha de crianças obesas são limitadas. Especificamente, um quadro detalhado dos determinantes mecânicos relacionados à energética da marcha de crianças obesas, para nosso conhecimento, é ausente na literatura. Neste sentido, o objetivo do presente estudo foi verificar os efeitos da obesidade nos parâmetros biomecânicos e metabólicos de crianças, durante a caminhada em diferentes velocidades. Para isso, participaram do estudo 24 crianças, entre sete e nove anos de idade, divididos em dois grupos (grupo de obesos (GO), com n=12 e grupo eutrófico (GE), com n=12), pareados por sexo. Foi realizada uma coleta cinemática (para determinar os componentes espaço-temporais e os componentes do trabalho mecânico) em conjunto com uma coleta metabólica (para determinar o custo energético da caminhada). Foi utilizada estatística descritiva, com médias e desvios padrão, além de análise de variância (ANOVA) de dois caminhos (para verificar os efeitos do grupo e das velocidades de caminhada) e foi utilizado o teste post-hoc de Bonferroni para localizar as diferenças. O nível de significância adotado foi α = 0,05. Os resultados demonstraram que há efeito da obesidade sobre a mecânica e a energética da caminhada de crianças. Crianças obesas utilizam uma estratégia locomotora em que há maior tempo de contato com o solo (em média 14% maior) durante a passada e maior comprimento de passada (em média 9% maior), o que pode estar relacionado com a manutenção da estabilidade entre os grupos. Na análise do trabalho mecânico total (J.kg-1.m-1), não foram identificadas diferenças significativas em nenhuma velocidade, apesar de as crianças obesas apresentarem maior trabalho interno nas maiores velocidades (4km.h-1 no GO foi 0,30 ± 0,04 e no GE foi 0,24 ± 0,04, p=0,022; 5km.h no GO foi 0,42 ± 0,09 e no GE foi 0,33 ± 0,03, p=0,041). A análise dos componentes metabólicos demonstrou importante influência da normalização dos dados, uma vez que, com a normalização pela massa corporal total e com o coeficiente alométrico, o grupo eutrófico apresentou maiores valores na maioria das velocidades, contudo sem a normalização (valores brutos) o custo metabólico foi maior para o grupo obeso em todas as velocidades. Conclui-se que a estratégia locomotora do grupo obeso foi eficiente em aumentar a estabilidade da caminhada, diminuir as diferenças esperadas quanto à realização de trabalho mecânico em relação ao grupo eutrófico, sendo mais econômicas na análise de quantidade de energia consumida por unidade de massa corporal e por unidade de metro percorrido, contudo menos econômicas na análise da quantidade de energia bruta consumida por tempo.Obesity is currently considered a disease with epidemic proportions. Overweight is related to the lack of physical activity at sufficient level and has been diagnosed from childhood. Several risk factors are associated with obesity, such as type 2 diabetes, hypertension, dyslipidemia and others. Walking practice is associated with a decreased in these risk factors, in addition to improved orthopedic and metabolic health, especially in obese children and adolescents. Although there is evidence about obese adolescents and adults, information regarding the mechanics of the gait of obese children are limited. Specifically, details of the mechanical determinants related to energy gait of obese children, to our knowledge, is absent in the literature. In this regard, the aim of this study was to investigate the obesity effects on biomechanical and metabolic parameters in children during walking at different speeds. The study included 24 children, between seven and nine years old, divided into two groups (obese group (OG), n=12; eutrophic group (EG), n=12), paired by sex. A kinematic collect was performed to determine the spatiotemporal parameters and the mechanical work components with a metabolic collect to determine the walking energy cost. Descriptive statistics were used with means and standard deviations, as well as a two-way ANOVA (to check the effects of the group and speeds) and we used the post-hoc test of Bonferroni to identify the differences. The significance level was α = 0.05. The results showed that there is influence of obesity on mechanics and energetics parameters in children’s walking. Obese children use a locomotors strategy in which there is longer stance time and (on average 14% higher) and greatest stride length (on average 9% higher), and it can be related to the maintenance of stability between groups. In the total mechanical work analyses, no significant differences were identified in any speeds, although obese children showed grater internal work in the higher speeds (4km.h-1 on OG was 0,30 ± 0,04 and on EG was 0,24 ± 0,04, p=0,022; 5km.h on OG was 0,42 ± 0,09 and on EG was 0,33 ± 0,03, p=0,041). The metabolic components analyses showed great influence of the data normalization, because with the normalization, by total body mass and by allometric coefficient normalization, the eutrophic group showed higher values in most speeds, but without normalization the gross metabolic cost was higher for the obese group at all speeds. We concluded that locomotors strategy of the obese group was effective to increase the stability of walking, reduce the expected differences on the achievement of mechanical work in relation to the eutrophic group, being more economical in the amount of energy expenditure by unity of total body mass, however less economic by a gross metabolic analyses.
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Teweleit, Sarah. "Le droit d'agir devant la Cour Européenne des Droits de l'Homme." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0552.
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Le droit d’agir devant la Cour européenne des droits de l’Homme est assurément unique dansl’ordre juridique international. Erigé en « pierre angulaire » du système européen de sauvegarde,bénéficie-t-il pour autant d’une protection à la hauteur de cette qualification? L’engorgementmanifeste de la Cour de Strasbourg place cette interrogation dans une actualité perpétuelle.L’étude de ce droit processuel supranational illustre l’existence simultanée de deux courantsprétoriens aux effets diamétralement opposés sur l’exercice du droit d’agir : l’un souple, provictima, qui ouvre largement le prétoire de la Cour et l’autre restreignant a contrario son accès. Sil’approche souple satisfait naturellement l’intérêt individuel des requérants, elle permet égalementà la Cour de bâtir un ordre public européen de protection des droits de l’Homme. Parallèlement,l’interprétation stricte des conditions d’accès repose sur la responsabilisation des acteurs dumécanisme européen et sous-tend un filtrage rigoureux des affaires individuelles. Le droit d’agirreprésente, par conséquent, une composante d’un système de protection de nature« constitutionnelle » évoluant aux rythmes des liens tissés entre les deux courants prétoriensévoqués. C’est en effet par un mouvement pendulaire entre l’ouverture et la fermeture du prétoirede la Cour de Strasbourg que la garantie durable du droit d’agir peut être assuréeThe right of action in front of the European Court of Human Rights is certainly unparalleled in theinternational legal order. In the light of the constant congestion at the Strasbourg Court, one canonly ask if this right is genuinely guaranteed as the corner stone that is intended to be in theEuropean system of protection. The analysis of this supranational procedural right reflects theexistence of two distinct case law dynamics that influence the right of action: the pro victimaeffect, widening the access to the Court, and the opposite restraining effect. The first effect, moreflexible, not only favors the individual interest of the plaintiff, but also allows the Court todevelop the European public order of human rights protection. In parallel, the restraining effect onthe grounds of access to the Court entails a rigorous filtering of the individual cases, in order toachieve an increased accountability on human rights protection both of States and individuals.Therefore, the right of action represents the component of what can be nowadays qualified of a« constitutional » system of Human rights protection. Moreover, the alternate dynamics, closingand opening access to the Court, describe a pendula movement that is essential for a sustainableright of action
Books on the topic "Pendulum movement"
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Pusat Penelitian dan Pengembangan HAM Yang Berat (Indonesia). Evaluasi mobilitas penduduk pasca konflik. Jakarta: Pusat Penelitian dan Pengembangan HAM Yang Berat, Badan Penelitian dan Pengembangan HAM, Departemen Hukum dan HAM RI, 2007.
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Lewis, Marianne W. Vicious and Virtuous Cycles. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198827436.003.0006.
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In this chapter we discuss how paradox theory proposes that contrasting approaches to paradox—interwoven and persistent contradictions—fuel vicious and virtuous cycles in organizations. Interwoven cognitive, emotional, and behavioural responses can trigger cyclical dynamics. Defensive responses reinforce counterproductive, either/or approaches, fostering stuckness in a struggle against the experience of tensions. In contrast, we explore the way in which engaging paradox enables movement that fosters both confidence and humility in one’s ability and need to continuously learn and change. The dramatic pendulum swings of the LEGO company serve as an illustration of this, enabling insights into these cycles and their fuel in practice.
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Harkins, Stephen G., and Kipling D. Williams. Introduction and Overview. Edited by Stephen G. Harkins, Kipling D. Williams, and Jerry Burger. Oxford University Press, 2016. http://dx.doi.org/10.1093/oxfordhb/9780199859870.013.1.
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The study of social influence has been central to social psychology since its inception. In fact, research on social influence began in the 1880s, predating the coining of the term social psychology. However, by the mid-1980s, interest in this area had waned. Now the pendulum is swinging back, as seen in growing interest in non-cognitive, motivational accounts. Our hope is that the publication of this volume will aid this movement. The chapters, written by leading scholars, cover a variety of topics in social influence, incorporating a range of levels of analysis (intrapersonal, interpersonal, and intragroup) and both source and target effects. The book also includes chapters on theories that are most relevant to social influence, as well as a set of chapters on social influence in applied settings. Finally, we include a section that considers the future of social influence in social psychology.
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Eller, Jonathan R. Futuria Fantasia. University of Illinois Press, 2017. http://dx.doi.org/10.5406/illinois/9780252036293.003.0006.
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This chapter focuses on Ray Bradbury's fanzine Futuria Fantasia, in which he championed the Technocracy movement based on the premise that if the technological infrastructure were more efficient, then everyone's life would be better. It discusses Bradbury's editorship of Futuria Fantasia, the second issue of which reflected his emerging editorial insight; it contained essays written by Henry Hasse and Henry Kuttner. It suggests that, in soliciting the Hasse and Kuttner contributions, Bradbury was initiating a debate on the state of writing in the science fiction field. The second issue also featured two stories by Hannes Bok, whose illustrations graced all of the fanzine's covers, as well as Bradbury's anonymous story “The Pendulum” and a poem entitled “Satan's Mistress.” The chapter concludes with an assessment of Bradbury's problems with the production of Futuria Fantasia, culminating in its demise after the fourth issue, which carried Bradbury's story “The Piper,” his first solo sale to the genre prozines.
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Dunphie, Chris. Pendulum of Battle: Operation Goodwood - July 1944. Pen & Sword Books Limited, 2004.
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Dunphie, Chris. PENDULUM OF BATTLE: Operation Goodwood - July 1944. Pen and Sword, 2005.
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Stewart, Frances, Gustav Ranis, and Emma Samman. The Politics of Progress in Human Development. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198794455.003.0008.
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This chapter analyses approaches to understanding the politics underlying success and failure on human development, which are of critical importance for progress, as shown in earlier chapters. It draws on Polanyi’s analysis of a long-term swing of a pendulum between emphasis on markets and emphasis on social objectives, and on theories of social movements and social change, for example put forward by Tarrow and Tilly. It illustrates the relevance of both these approaches with empirical examples. The chapter contends that democracy is a permissive condition, providing space for collective action (social movements, workers’ movements action, and political parties) to promote change favouring human development. The chapter also discusses how far politics has been incorporated into the human development and capabilities approaches, considering and critiquing the view that what is needed is a ‘democratic consensus’.
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Witte, Hartmut, Martin S. Fischer, Holger Preuschoft, Danja Voges, Cornelius Schilling, and Auke Jan Ijspeert. Quadruped locomotion. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780199674923.003.0031.
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This chapter considers locomotion in living machines, focusing particularly on mammals and on the possibility of designing mammal-like quadrupedal robots. Locomotion is the movement of an organism or a machine from one place to the other, covering a defined minimal distance. In organisms, locomotion usually is driven by a central element and/or appendices. Vertebrates are characterized by the existence of a spine and the mechanics of an endoskeletal system. The amphibio-reptile type of vertebrate locomotion shows oscillations of the body stem mainly in the horizontal, which are coupled to the ground by legs with two long segments. The vertical oscillations of the body stem in the mammal type of quadrupedal locomotion are coupled to the ground by legs with three long segments. For any size of animal and any allometric relation between mass and ground reaction force the resonance mechanisms of gravitational and spring-mass-pendula are tuned to one each other. Elongated feet allow torque exchange with the substrate.
Book chapters on the topic "Pendulum movement"
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Eecke, Maria Ver. "Balance Arises out of Movement and Stillness." In The Swing of the Pendulum, 101–10. Rotterdam: SensePublishers, 2017. http://dx.doi.org/10.1007/978-94-6351-224-4_9.
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Estevão, Ivan Ramos. "The Movement of the Pendulum and the Spiral Turn: An Analysis of Lacan’s XXVI Lesson from Seminar VIII: Commentary on Session XXVI." In Reading Lacan’s Seminar VIII, 267–77. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-32742-2_22.
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Roldán, Geovanny Palomino, and Ernesto Suaste Gómez. "Recording and Analysis of the Vestibulo-Ocular Reflex with Pendular Movement in the Vertical Plane." In IFMBE Proceedings, 445–48. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-30648-9_57.
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Matthys, Robert James. "Pendulum air movement: A failed experiment." In Accurate Clock Pendulums, 191–94. Oxford University Press, 2004. http://dx.doi.org/10.1093/acprof:oso/9780198529712.003.0028.
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Matthys, Robert James. "Pendulum air movement: A second try." In Accurate Clock Pendulums, 195–204. Oxford University Press, 2004. http://dx.doi.org/10.1093/acprof:oso/9780198529712.003.0029.
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Matesan, Ioana Emy. "The Rise of the Muslim Brotherhood and the Potential for Violent Escalation." In The Violence Pendulum, 37–78. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780197510087.003.0003.
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This chapter revisits the early history of the Muslim Brotherhood to understand why an organization that started out as a nonviolent religious movement came to be associated with violence. Many blame this on the harsh repression under President Gamal Abdel Nasser. However, the analysis shows that the drift toward violence started much earlier. Reconstructing the sequence of events between 1936 and 1948, the chapter reveals that what initially politicized the Brotherhood was the presence of British troops in Egypt and Palestine. The formation of an armed wing led to competition over authority within the group, which incentivized violent escalation. The chapter then focuses on the period between 1954 and 1970 and shows that repression had a dual effect. On the one hand, it inspired new jihadi interpretations, which were particularly appealing to younger members. On the other hand, the prisons were also the backdrop against which the Brotherhood became convinced that violence was futile.
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Doleys, Daniel M., and Nicholas D. Doleys. "The Psychology of Opioid Tapering." In Psychological and Psychiatric Issues in Patients with Chronic Pain, edited by Daniel M. Doleys and Nicholas D. Doleys, 231–50. Oxford University Press, 2021. http://dx.doi.org/10.1093/med/9780197544631.003.0023.
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The pendulum has swung; in this case, it may be a double pendulum. The double pendulum is a pendulum hanging from a pendulum. It is a simple physical system used in physics to demonstrate mathematical chaos. When the motion of its tip is monitored, it appears very predictable at the outset, but soon reveals a very chaotic and unpredictable pattern. It is very difficult to know where the tip of the double pendulum will be at any given time in the future. This seems to describe the course of the use of opioids, especially for the treatment of chronic pain. Once, all but ignored, then heralded, and then demonized. At every step of the way, pundits will argue the incompleteness, absence, or misinterpretation of existing data. It is important to understand the psychological environment is which the opioid tapering movement occurs and to carefully consider the process in the context of the individual patient. Simply instituting another set of presumptive evidence-based guidelines could have unforeseen, and potentially tragic, consequences for the patient.
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Dembour, Marie-Benedicte. "Following the movement of a pendulum: between universalism and relativism." In Culture and Rights, 56–79. Cambridge University Press, 2001. http://dx.doi.org/10.1017/cbo9780511804687.005.
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"Background of Metamodernism and Metaliteracy." In Metamodernism and Changing Literacy, 1–19. IGI Global, 2020. http://dx.doi.org/10.4018/978-1-7998-3534-9.ch001.
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This chapter introduces metamodernism and metaliteracy with a background in both philosophical and historical contexts. Setting the scene for understanding literacy in the early part of the 21st century may help educators and learners at any age balance communication in physical, virtual, and augmented spaces through an understanding of the constantly swinging pendulum of polar extremes in a rapidly changing cultural era. Metamodernism, as a philosophical movement, allows room to respect traditional knowledge and wisdom of the past alongside the excitement of innovation, creating optimism about learning in the future. Definitions of current nomenclature are introduced with the goal of examining literacy through an emerging cultural lens leading to a discussion of both theory and practice.
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Bullock, Charles S., Susan A. MacManus, Jeremy D. Mayer, and Mark J. Rozell. "The Changing Demographics of the South and Its Impact on National Politics." In The South and the Transformation of U.S. Politics, 21–49. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780190065911.003.0002.
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The South has grown more in the past fifty years than any other region, leading to major changes in its economy and the racial/ethnic, gender, generational, socioeconomic, and political composition of its electorate. In the fifty years since the civil rights movement and Martin Luther King Jr.’s assassination, the South’s politics have become more polarized, with sharp differences by race, place of birth, age, education, income, and gender. Most of the changes occurred during a period of realignment, during which Republicans expanded their regional dominance. But continued in-migration, accompanied by economic diversification and racial/ethnic and generational shifts, is beginning to push the political pendulum in the opposite direction. This “redirection” is most noticeable in the region’s high growth states, particularly in their fast-growing metropolitan areas characterized by larger concentrations of young, minority (and more Democratic-leaning) voters. Overall, this chapter lends credibility to the “demographics is destiny” thesis.
Conference papers on the topic "Pendulum movement"
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Kayumov, Oleg. "Time-optimal movement of an elliptical pendulum." In 2020 15th International Conference on Stability and Oscillations of Nonlinear Control Systems (Pyatnitskiy's Conference) (STAB). IEEE, 2020. http://dx.doi.org/10.1109/stab49150.2020.9140628.
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Shimada, Akira, and Naoya Hatakeyama. "Movement control of two-wheeled inverted pendulum robots considering robustness." In SICE 2008 - 47th Annual Conference of the Society of Instrument and Control Engineers of Japan. IEEE, 2008. http://dx.doi.org/10.1109/sice.2008.4655245.
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Naoya Hatakeyama and Akira Shimada. "Movement control using zero dynamics of two-wheeled inverted pendulum robot." In 2008 10th IEEE International Workshop on Advanced Motion Control (AMC). IEEE, 2008. http://dx.doi.org/10.1109/amc.2008.4516038.
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Huang, Yan, Hong Dai, and Songlin He. "The Research on the Nonlinear Torsion Movement of Three Wire Pendulum." In 2015 International Conference on Intelligent Systems Research and Mechatronics Engineering. Paris, France: Atlantis Press, 2015. http://dx.doi.org/10.2991/isrme-15.2015.301.
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Choi, Changrak. "Control of Inverted Pendulum Using Only Vertical Force via Harmonic Oscillation." In ASME 2013 Dynamic Systems and Control Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/dscc2013-3859.
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Control of an inverted pendulum using horizontal force (e.g. cart-pole) is a well-established problem. However, there is no work in the literature that addresses controlling an inverted pendulum using only vertical force without horizontal movement. In this paper, control algorithm is presented that can control the inverted pendulum via only vertical force within the operating range of the given system. In the process, the dynamic stabilizing effect of vertical harmonic oscillation acting on inverted pendulum is exploited and previous works on the analysis of the stabilizing effect is utilized. The result is a nonlinear controller that combines sliding mode and energy shaping control which is capable of stabilizing the pendulum upright as well as at any titled angle within the region of attraction described. This is done for pendulum starting at any initial angle while maintaining vertical movement of the inverted pendulum within the prescribed space limit.
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Ohhira, Takashi, and Akira Shimda. "Linear model predictive movement control with obstacle avoidance for an inverted pendulum robot." In 2018 15th International Workshop on Advanced Motion Control (AMC). IEEE, 2018. http://dx.doi.org/10.1109/amc.2019.8371067.
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Lin Xiao, Zushu Li, and Yuanhong Dan. "The Up-Down giant-circle movement control of cart-double pendulum using HSIC." In 2010 8th World Congress on Intelligent Control and Automation (WCICA 2010). IEEE, 2010. http://dx.doi.org/10.1109/wcica.2010.5554895.
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White, Paul F., Daria S. Keo, and Gerti Kola. "Improved Overhead Contact System Operation With Inclined Pendulum Suspension." In 2018 Joint Rail Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/jrc2018-6105.
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Overhead Contact Systems for electric transit vehicles utilize catenary or single contact wire suspended from cantilevers, bracket arms or span wires. For single contact wire, inclined pendulum suspension provides optimal performance for pantograph or trolley pole current collectors, though it is under-utilized in the United States. Typical suspension for single contact wire consists of direct suspension hangers or stitch suspension with steady arms where stagger is achieved by pulling off the contact wire with the hanger (direct suspension) or steady arms (stitch suspension). This results in the full weight of the contact wire in the span length being supported by the stitch or line insulator. This rigid point of attachment results in a heavy, stiff suspension leading to current collector bouncing, arcing and premature contact wire wear as the upward movement of the wire is restricted and a hard spot is created. It also results in excessive sag at elevated temperatures and contributes to an increased angle at the support span approach. Inclined pendulums can be utilized in constant tension systems or variable tensioned systems where they impart a semi-constant tensioning into the line and keep the wire tension relatively stable over a particular temperature range. The expansion/contraction of the contact wire is taken up in the inclination of the pendulums where they rise or fall so that the tension and sag in the contact wire remains relatively consistent. In addition, they provide less resistance to uplift of the current collectors at the suspension point so that rising of the contact wire occurs as the collector approaches and passes under it. The vertical angle of the contact wire approaching the span support is kept to minimum levels and collector performance during hot weather conditions tends to remain trouble free. Further, the energy wave set up in the wire from the moving collector is not grossly reflected at the suspension point as with direct suspension thus allowing the collector to pass through smoothly without bounce or loss of continuous contact. This paper describes the benefits of inclined pendulums in constant and variable tensioned systems such as creating a semi-constant tensioning effect, preventing current collector bounce and premature contact wire wear at the supports by reducing the uplift resistance on current collectors. It also provides the least visual obtrusiveness of all the suspension systems. In addition, this paper will present the associated costs of the inclined pendulum suspensions.
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Hazrati Ashtiani, Iman, Subhash Rakheja, A. K. W. Ahmed, and Jimin Zhang. "Hunting Analysis of a Partially-Filled Railway Tank Car." In 2015 Joint Rail Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/jrc2015-5631.
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General purpose railway tank cars similar to road tankers are known to transport liquid cargo in partial-fill state due to variations in liquid cargo density and governing axle load limits. It is widely reported that the cargo movements constitute additional forces and moments that could strongly affect the wheel-rail interactions and coupling forces, and thereby the directional dynamics of the wagon. In this study, the linear slosh theory is used to describe the liquid cargo movement in the roll plane by a simple pendulum, which is integrated into a comprehensive nonlinear multi-body model of a three-piece truck to study the effects of liquid cargo slosh on lateral dynamics of the tank car. The model also incorporates the nonlinear secondary suspension restoring and damping forces, attributed to friction of the wedges, using the non-smooth contact method in addition to the geometric constraints of various components. The wheel/rail contact forces are simulated considering non-elliptical wheel-rail contact using the FASTSIM algorithm. The lateral dynamic responses of the multi-body model of a freight car with partially filled liquid load and an equivalent rigid cargo are evaluated to study the effect of cargo movement on the critical speed and the wheelset hunting oscillations frequency. The results obtained considering different fill ratios of the liquid cargo suggest that the fluid slosh yields additional damping effect on the lateral dynamics of the car. Liquid cargo movement within partly-filled tank car could thus yield a beneficial influence on the wheelset hunting. This was evidenced from the phase relationship between the lateral oscillations of the pendulum and the bogie/wheelset. Consequently, a partially filled tanker resulted in relatively higher critical hunting velocity compared to that of the wagon with equivalent rigid cargo.
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Kanazawa, Masao, Shigeki Nakaura, and Mitsuji Sampei. "Inverse optimal control problem for bilinear systems: Application to the inverted pendulum with horizontal and vertical movement." In 2009 Joint 48th IEEE Conference on Decision and Control (CDC) and 28th Chinese Control Conference (CCC). IEEE, 2009. http://dx.doi.org/10.1109/cdc.2009.5399912.
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