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Sample records for allowing intralimb kinematic

  1. Intralimb Coordination Patterns in Absent, Mild, and Severe Stages of Diabetic Neuropathy: Looking Beyond Kinematic Analysis of Gait Cycle.

    Directory of Open Access Journals (Sweden)

    Liu Chiao Yi

    Full Text Available Diabetes Mellitus progressively leads to impairments in stability and joint motion and might affect coordination patterns, mainly due to neuropathy. This study aims to describe changes in intralimb joint coordination in healthy individuals and patients with absent, mild and, severe stages of neuropathy.Forty-seven diabetic patients were classified into three groups of neuropathic severity by a fuzzy model: 18 without neuropathy (DIAB, 7 with mild neuropathy (MILD, and 22 with moderate to severe neuropathy (SVRE. Thirteen healthy subjects were included as controls (CTRL. Continuous relative phase (CRP was calculated at each instant of the gait cycle for each pair of lower limb joints. Analysis of Variance compared each frame of the CRP time series and its standard deviation among groups (α = 5%.For the ankle-hip CRP, the SVRE group presented increased variability at the propulsion phase and a distinct pattern at the propulsion and initial swing phases compared to the DIAB and CTRL groups. For the ankle-knee CRP, the 3 diabetic groups presented more anti-phase ratios than the CTRL group at the midstance, propulsion, and terminal swing phases, with decreased variability at the early stance phase. For the knee-hip CRP, the MILD group showed more in-phase ratio at the early stance and terminal swing phases and lower variability compared to all other groups. All diabetic groups were more in-phase at early the midstance phase (with lower variability than the control group.The low variability and coordination differences of the MILD group showed that gait coordination might be altered not only when frank evidence of neuropathy is present, but also when neuropathy is still incipient. The ankle-knee CRP at the initial swing phase showed distinct patterns for groups from all degrees of neuropathic severity and CTRLs. The ankle-hip CRP pattern distinguished the SVRE patients from other diabetic groups, particularly in the transitional phase from stance to

  2. Aging does not affect the intralimb coordination elicited by slip-like perturbation of different intensities.

    Science.gov (United States)

    Aprigliano, Federica; Martelli, Dario; Tropea, Peppino; Pasquini, Guido; Micera, Silvestro; Monaco, Vito

    2017-09-01

    This study was aimed at verifying whether aging modifies intralimb coordination strategy during corrective responses elicited by unexpected slip-like perturbations delivered during steady walking on a treadmill. To this end, 10 young and 10 elderly subjects were asked to manage unexpected slippages of different intensities. We analyzed the planar covariation law of the lower limb segments, using the principal component analysis, to verify whether elevation angles of older subjects covaried along a plan before and after the perturbation. Results showed that segments related to the perturbed limbs of both younger and older people do not covary after all perturbations. Conversely, the planar covariation law of the unperturbed limb was systematically held for younger and older subjects. These results occurred despite differences in spatio-temporal and kinematic parameters being observed among groups and perturbation intensities. Overall, our analysis revealed that aging does not affect intralimb coordination during corrective responses induced by slip-like perturbation, suggesting that both younger and older subjects adopt this control strategy while managing sudden and unexpected postural transitions of increasing intensities. Accordingly, results corroborate the hypothesis that balance control emerges from a governing set of biomechanical invariants, that is, suitable control schemes (e.g., planar covariation law) shared across voluntary and corrective motor behaviors, and across different sensory contexts due to different perturbation intensities, in both younger and older subjects. In this respect, our findings provide further support to investigate the effects of specific task training programs to counteract the risk of fall. NEW & NOTEWORTHY This study was aimed at investigating how aging affects the intralimb coordination of lower limb segments, described by the planar covariation law, during unexpected slip-like perturbations of increasing intensity. Results

  3. Developing a technique to measure intra-limb coordination in gait: applicable to children with cerebral palsy.

    Science.gov (United States)

    Farmer, Sybil E; Pearce, Gillian; Stewart, Caroline

    2008-08-01

    Lower limb intra-limb coordination was investigated using sagittal plane kinematic data extracted from gait data recorded using a Vicon system (Vicon Motion Systems Ltd., Oxford, UK) of 20 normal (N) and 20 children with cerebral palsy (CP). Walking speed, maximum and minimum flexion and range of motion (ROM) were calculated. The repeatability of the data was checked by calculating the coefficient of multiple correlation. Data were also processed to determine angular velocity of hip and knee joints. A logical spreadsheet was devised to determine when both joints moved in the same direction (in-phase), in different directions (antiphase, AP) or if either joint was immobile (JS). In-phase joint motion was further subdivided into in-phase flexion (IPF) and in-phase extension (IPE), which comprises in-phase during stance phase (IPEst) and in-phase during swing phase (IPEsw). Data were processed using two threshold values for angular velocity below which the joint was considered to be immobile. The threshold values used were 0.05 degrees /% of gait cycle and 0.025 degrees /% of gait cycle. Children with cerebral palsy had reduced ROM and walked more slowly than normal children. There are significant differences between N and cerebral palsy coordination phases with marginally greater significance at the 0.05 degrees /% threshold for most component parameters; the exception being in-phase flexion. It is therefore suggested that this threshold value (0.05 degrees /%) is used for future work.

  4. Manual Dexterity and Intralimb Coordination Assessment to Distinguish Different Levels of Impairment in Boccia Players with Cerebral Palsy

    Directory of Open Access Journals (Sweden)

    Alba Roldan

    2017-11-01

    Full Text Available BackgroundBoccia is a paralympic sport played by athletes with severe neurological impairments affecting all four limbs. Impaired manual dexterity (MD and intralimb coordination (ILC may limit individuals’ ability to perform certain activities such as grasping, releasing, or manipulating objects, which are essential tasks for daily life or to participate in para sports such as boccia. However, there are currently no specific instruments available to assess hand–arm coordination in boccia players with severe cerebral palsy (CP.PurposeTo design new sport-specific coordination tests to assess impaired MD and ILC in boccia players; afterward, quantify to what extent their coordination is impaired compared to a control group (CG without neurological impairments.MethodsSeventy-three recreational boccia players with severe CP (BC1: age = 34.01 ± 16.43 years; BC2: age = 33.97 ± 14.29 years, and 19 healthy adults (age = 27.89 ± 7.08 years completed the test battery. The Box and Block test (BBT and Box and Ball test (BBLT were used to assess MD and four tapping tests to assess upper ILC.ResultsBoth MD tests were able to discriminate between sport classes. Boccia players obtained better scores in the BBLT in comparison to the BBT, showing that the BBLT had more appropriate testing features. On the other hand, only one of the ILC tests was able to discriminate between sport classes, displaying the highest practical significance (d = −1.12. Participants with CP scored significantly worse in all the coordination tests compared to the CG.ConclusionUsing sport-specific equipment facilitated grasp function during the MD assessment. Regarding the ILC, the type of movement (continuous vs. discrete seems to be more relevant for classification than the movement direction (vertical vs. horizontal or the presence of a ball.

  5. Rational kinematics

    CERN Document Server

    Angeles, Jorge

    1988-01-01

    A rational study of kinematics is a treatment of the subject based on invariants, i.e., quantities that remain essentially unchanged under a change of observer. An observer is understood to be a reference frame supplied with a clock (Truesdell 1966). This study will therefore include an introduction to invariants. The language of these is tensor analysis and multilinear algebra, both of which share many isomorphic relations, These subjects are treated in full detail in Ericksen (1960) and Bowen and Wang (1976), and hence will not be included here. Only a short account of notation and definitions will be presented. Moreover, definitions and basic concepts pertaining to the kinematics of rigid bodies will be also included. Although the kinematics of rigid bodies can be regarded as a particular case of the kinematics of continua, the former deserves attention on its own merits for several reasons. One of these is that it describes locally the motions undergone by continua. Another reason is that a whole area of ...

  6. CHILD ALLOWANCE

    CERN Multimedia

    Human Resources Division

    2001-01-01

    HR Division wishes to clarify to members of the personnel that the allowance for a dependent child continues to be paid during all training courses ('stages'), apprenticeships, 'contrats de qualification', sandwich courses or other courses of similar nature. Any payment received for these training courses, including apprenticeships, is however deducted from the amount reimbursable as school fees. HR Division would also like to draw the attention of members of the personnel to the fact that any contract of employment will lead to the suppression of the child allowance and of the right to reimbursement of school fees.

  7. Parallel kinematics type, kinematics, and optimal design

    CERN Document Server

    Liu, Xin-Jun

    2014-01-01

    Parallel Kinematics- Type, Kinematics, and Optimal Design presents the results of 15 year's research on parallel mechanisms and parallel kinematics machines. This book covers the systematic classification of parallel mechanisms (PMs) as well as providing a large number of mechanical architectures of PMs available for use in practical applications. It focuses on the kinematic design of parallel robots. One successful application of parallel mechanisms in the field of machine tools, which is also called parallel kinematics machines, has been the emerging trend in advanced machine tools. The book describes not only the main aspects and important topics in parallel kinematics, but also references novel concepts and approaches, i.e. type synthesis based on evolution, performance evaluation and optimization based on screw theory, singularity model taking into account motion and force transmissibility, and others.   This book is intended for researchers, scientists, engineers and postgraduates or above with interes...

  8. Kinematic space and wormholes

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jian-dong [TianQin Research Center for Gravitational Physics, Sun Yat-sen University, Zhuhai 519082, Guangdong (China); Chen, Bin [Department of Physics and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China); Collaborative Innovation Center of Quantum Matter, 5 Yiheyuan Rd, Beijing 100871 (China); Center for High Energy Physics, Peking University, 5 Yiheyuan Rd, Beijing 100871 (China)

    2017-01-23

    The kinematic space could play a key role in constructing the bulk geometry from dual CFT. In this paper, we study the kinematic space from geometric points of view, without resorting to differential entropy. We find that the kinematic space could be intrinsically defined in the embedding space. For each oriented geodesic in the Poincaré disk, there is a corresponding point in the kinematic space. This point is the tip of the causal diamond of the disk whose intersection with the Poincaré disk determines the geodesic. In this geometric construction, the causal structure in the kinematic space can be seen clearly. Moreover, we find that every transformation in the SL(2,ℝ) leads to a geodesic in the kinematic space. In particular, for a hyperbolic transformation defining a BTZ black hole, it is a timelike geodesic in the kinematic space. We show that the horizon length of the static BTZ black hole could be computed by the geodesic length of corresponding points in the kinematic space. Furthermore, we discuss the fundamental regions in the kinematic space for the BTZ blackhole and multi-boundary wormholes.

  9. Inverse Kinematics using Quaternions

    DEFF Research Database (Denmark)

    Henriksen, Knud; Erleben, Kenny; Engell-Nørregård, Morten

    In this project I describe the status of inverse kinematics research, with the focus firmly on the methods that solve the core problem. An overview of the different methods are presented Three common methods used in inverse kinematics computation have been chosen as subject for closer inspection....

  10. Advances in robot kinematics

    CERN Document Server

    Khatib, Oussama

    2014-01-01

    The topics addressed in this book cover the whole range of kinematic analysis, synthesis and design and consider robotic systems possessing serial, parallel and cable driven mechanisms. The robotic systems range from being less than fully mobile to kinematically redundant to overconstrained.  The fifty-six contributions report the latest results in robot kinematics with emphasis on emerging areas such as design and control of humanoids or humanoid subsystems. The book is of interest to researchers wanting to bring their knowledge up to date regarding modern topics in one of the basic disciplines in robotics, which relates to the essential property of robots, the motion of mechanisms.

  11. Biquaternions and relativistic kinematics

    International Nuclear Information System (INIS)

    Bogush, A.A.; Kurochkin, Yu.A.; Fedorov, F.I.

    1979-01-01

    The problems concerning the use of quaternion interpretation of the Lorentz group vector parametrization are considered for solving relativistic kinematics problems. A vector theory convenient for describing the characteristic features of the Lobachevsky space is suggested. The kinematics of elementary particle scattering is investigated on the basis of this theory. A synthesis of vector parametrization and of quaternion calculation has been shown to lead to natural formulation of the theory of vectors in the three-dimensional Lobachevsky space, realized on mass hyperboloids of relativistic particles

  12. Kinematics and Dynamics of Roller Chain Drives

    DEFF Research Database (Denmark)

    Fuglede, Niels

    There are two main subjects of this work: Kinematic and dynamic modeling and analysis of roller chain drives. In the kinematic analysis we contribute first with a complete treatment of the roller chain drive modeled as a four-bar mechanism. This includes a general, exact and approximate analysis...... which is useful for predicting the characteristic loading of the roller chain drive. As a completely novel contribution, a kinematic model and analysis is presented which includes both spans and sprockets in a simple chain drive system. A general procedure for determination of the total wrapping length...... is presented, which also allows for exact sprocket center positions for a chain with a given number of links. Results show that the total chain wrapping length varies periodically with the tooth frequency. These results are of practical importance to both the design, installation and operation of roller chain...

  13. Teaching about Kinematics

    Science.gov (United States)

    Nelson, Jane Bray; Nelson, Jim

    2009-01-01

    Written by Jim and Jane Nelson, Teaching About Kinematics is the latest AAPT/PTRA resource book. Based on physics education research, the book provides teachers with the resources needed to introduce students to some of the fundamental building blocks of physics. It is a carefully thought-out, step-by-step laboratory-based introduction to the…

  14. Kinematic Analysis Towards Glueballs

    CERN Document Server

    Giani, Simone; Trentadue, Luca

    2013-01-01

    In the present work a consistent kinematic-based framework for glueball states is proposed. It relates the glueball, the Pomeron, QCD lattice calculations, the $0^{++}$ scalar states $f_0(1710)$ and $\\chi_{c0}(1P)$, the $2^{++}$ states $f_J(2220)$ and $\\chi_{c2}(2P)$, the baryonic charmed state $\\Xi_c^+(2645)$ and color transparency.

  15. Calculating gait kinematics using MR-based kinematic models.

    Science.gov (United States)

    Scheys, Lennart; Desloovere, Kaat; Spaepen, Arthur; Suetens, Paul; Jonkers, Ilse

    2011-02-01

    Rescaling generic models is the most frequently applied approach in generating biomechanical models for inverse kinematics. Nevertheless it is well known that this procedure introduces errors in calculated gait kinematics due to: (1) errors associated with palpation of anatomical landmarks, (2) inaccuracies in the definition of joint coordinate systems. Based on magnetic resonance (MR) images, more accurate, subject-specific kinematic models can be built that are significantly less sensitive to both error types. We studied the difference between the two modelling techniques by quantifying differences in calculated hip and knee joint kinematics during gait. In a clinically relevant patient group of 7 pediatric cerebral palsy (CP) subjects with increased femoral anteversion, gait kinematic were calculated using (1) rescaled generic kinematic models and (2) subject-specific MR-based models. In addition, both sets of kinematics were compared to those obtained using the standard clinical data processing workflow. Inverse kinematics, calculated using rescaled generic models or the standard clinical workflow, differed largely compared to kinematics calculated using subject-specific MR-based kinematic models. The kinematic differences were most pronounced in the sagittal and transverse planes (hip and knee flexion, hip rotation). This study shows that MR-based kinematic models improve the reliability of gait kinematics, compared to generic models based on normal subjects. This is the case especially in CP subjects where bony deformations may alter the relative configuration of joint coordinate systems. Whilst high cost impedes the implementation of this modeling technique, our results demonstrate that efforts should be made to improve the level of subject-specific detail in the joint axes determination. Copyright © 2010 Elsevier B.V. All rights reserved.

  16. Shot-put kinematics

    Science.gov (United States)

    DeLuca, R.

    2005-11-01

    The problem of the optimum throw in the shot-put discipline is analysed by relaxing the assumption that the height H, from which the athlete releases the shot, does not depend on the angle θ which the arm of the putter makes with the horizontal axis. In this context, the kinematics of the shot-put is studied and results are compared with the traditional analysis, which considers the height H, the angle θ and the modulus V0 of the initial velocity of the metal sphere as independent parameters.

  17. Kinematic geometry of gearing

    CERN Document Server

    Dooner, David B

    2012-01-01

    Building on the first edition published in 1995 this new edition of Kinematic Geometry of Gearing has been extensively revised and updated with new and original material. This includes the methodology for general tooth forms, radius of torsure', cylinder of osculation, and cylindroid of torsure; the author has also completely reworked the '3 laws of gearing', the first law re-written to better parallel the existing 'Law of Gearing" as pioneered by Leonard Euler, expanded from Euler's original law to encompass non-circular gears and hypoid gears, the 2nd law of gearing describing a unique relat

  18. Kinematic adjustments to seismic recordings

    Energy Technology Data Exchange (ETDEWEB)

    Telegin, A.N.; Levii, N.V.; Volovik, U.M.

    1981-01-01

    The introduction of kinematic adjustments by adding the displaced blocks is studied theoretically and in test seismograms. The advantage to this method resulting from the weight variation in the trace is demonstrated together with its kinematic drawback. A variation on the displaced block addition method that does not involve realignment of the travel time curves and that has improved amplitude characteristics is proposed.

  19. The co-ordinatization of the kinematical vectors

    International Nuclear Information System (INIS)

    Tempelman, W.

    1979-01-01

    The process of transforming the co-ordinates of a three-dimensional vector, conceived as a geometric object, between inertial co-ordinate systems is defined as a co-ordinatization process. The vectors obtained by co-ordinatizing the kinematical vectors represent an extension of kinematical theory, existing on a par with the standard Lorentz transformation equations. These two different approaches to the transformation of the kinematical vectors represent transformations of two forms of spatial information between inertial co-ordinate systems. The new co-ordinatization approach potentially allows a classical geometrization of the vector laws of physics. The kinematical vector results obtained from the co-ordinatization process can be experimentally verified. (author)

  20. Kinematics in special and general relativity

    International Nuclear Information System (INIS)

    Woodside, R.W.M.

    1979-05-01

    This thesis investigates the problem of motion for extended bodies from the viewpoint of classical field theory, where the classical field is the body's energy-momentum or matter tensor. In special relativity a symmetric and divergence-free matter tensor combined with inertial frames is used to generate a kinematics for extended bodies. In general relativity the author suggests an analogous kinematics and applies it to the simplest non-trivial example of static, spherical stars, looking for special sets of vector fields whose matter currents are conserved. Such a set of ten vector fields defines a special frame, and integrals of the conserved matter currents define ten momenta whcih give the kinematics. Application of de Rham cohomology theory shows that the conserved matter currents for isolated bodies will have mechanical potentials which enable the momenta to be found from flux integrals evaluated in the vacuum region surrounding the body. These potentials contain the full Riemann curvature, allowing a body's general relativistic momenta to be determined by its vacuum graviational field

  1. The kinematics of lopsided galaxies

    OpenAIRE

    Noordermeer, Edo; Sparke, Linda S.; Levine, Stephen E.

    2001-01-01

    Lopsidedness is a common feature in galaxies, both in the distribution of light and in the kinematics. We investigate the kinematics of a model for lopsided galaxies that consists of a disc lying off-centre in a dark halo, and circling around the halo centre. We search for families of stable, closed, non-crossing orbits, and assume that gas in our galaxies moves on these orbits. Several of our models show strong lopsided gas kinematics, especially the ones in which the disc spins around its a...

  2. Color-Kinematics Duality in Multi-Regge Kinematics and Dimensional Reduction

    CERN Document Server

    Johansson, Henrik; Campillo, Eduardo Serna; Vazquez-Mozo, Miguel A

    2013-01-01

    In this note we study the applicability of the color-kinematics duality to the scattering of two distinguishable scalar matter particles with gluon emission in QCD, or graviton emission in Einstein gravity. Previous analysis suggested that direct use of the Bern-Carrasco-Johansson double-copy prescription to matter amplitudes does not reproduce the gravitational amplitude in multi-Regge kinematics. This situation, however, can be avoided by extensions to the gauge theory, while maintaning the same Regge limit. Here we present two examples of these extensions: the introduction of a scalar contact interaction and the relaxation of the distinguishability of the scalars. In both cases new diagrams allow for a full reconstruction of the correct Regge limit on the gravitational side. Both modifications correspond to theories obtained by dimensional reduction from higher-dimensional gauge theories.

  3. Color-kinematics duality in multi-Regge kinematics and dimensional reduction

    Science.gov (United States)

    Johansson, Henrik; Vera, Agustín Sabio; Campillo, Eduardo Serna; Vázquez-Mozo, Miguel Á.

    2013-10-01

    In this note we study the applicability of the color-kinematics duality to the scattering of two distinguishable scalar matter particles with gluon emission in QCD, or graviton emission in Einstein gravity. Previous analysis suggested that direct use of the Bern-Carrasco-Johansson double-copy prescription to matter amplitudes does not reproduce the gravitational amplitude in multi-Regge kinematics. This situation, however, can be avoided by extensions to the gauge theory, while maintaning the same Regge limit. Here we present two examples of these extensions: the introduction of a scalar contact interaction and the relaxation of the distinguishability of the scalars. In both cases new diagrams allow for a full reconstruction of the correct Regge limit on the gravitational side. Both modifications correspond to theories obtained by dimensional reduction from higher-dimensional gauge theories.

  4. Trading sulfur dioxide allowances

    International Nuclear Information System (INIS)

    Goldburg, C.B.; Lave, L.B.

    1992-01-01

    The 1990 Clean Air Act is aimed at generators larger than 25 MW, as these are the largest polluters. Market incentives give each source an emissions allocation but also flexibility. If a plant has lower emissions than the target, it can sell the 'surplus' emissions as allowances to plants that fail to meet the target. Only a few trades have occurred to date. Market-based incentives should lower the costs of improving environmental quality significantly. However, currently institutional dificulties hamper implementation

  5. Latest Advances in Robot Kinematics

    CERN Document Server

    Husty, Manfred

    2012-01-01

    This book is  of interest to researchers inquiring about modern topics and methods in the kinematics, control and design of robotic manipulators. It considers the full range of robotic systems, including serial, parallel and cable driven manipulators, both planar and spatial. The systems range from being less than fully mobile to kinematically redundant to overconstrained. In addition to recognized areas, this book also presents recent advances in emerging areas such as the design and control of humanoids and humanoid subsystems, and the analysis, modeling and simulation of human body motions, as well as the mobility analysis of protein molecules and the development of machines which incorporate man.

  6. Run kinematics with and without a jogging stroller.

    Science.gov (United States)

    O'Sullivan, Rory; Kiernan, Damien; Malone, Ailish

    2016-01-01

    Jogging strollers have become increasingly popular as they allow a parent the freedom to run without having to leave their children. Few studies have examined the effects of running with a stroller and no study to date has examined the effects on joint kinematics. The aim of this study was to compare lower limb and trunk kinematics while running with and without a jogging stroller. Participants (N=15) ran on a 16-metre indoor runway, with and without a stroller, at their self-selected comfortable training speed. Three-dimensional trunk and lower limb kinematics were assessed using the CODA cx1 active marker system. The jogging stroller led to reduced movement of the trunk in both the transverse [mean difference -11.4°, 95% confidence interval (CI) (-14.8°, -8.2°), pjogging strollers lead to minor changes in trunk, pelvis and hip kinematics with no significant changes at the knee and ankle. Due to the changes in kinematics we suggest that flexibility work for the spine, pelvis and hips may be recommended. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Top quark mass and kinematics

    Energy Technology Data Exchange (ETDEWEB)

    Barberis, Emanuela; /Northeastern U.

    2006-05-01

    A summary of the results on the measurement of the Top Quark mass and the study of the kinematics of the t{bar t} system at the Tevatron collider is presented here. Results from both the CDF and D0 collaborations are reported.

  8. Kinematic Parameters of Signed Verbs

    Science.gov (United States)

    Malaia, Evie; Wilbur, Ronnie B.; Milkovic, Marina

    2013-01-01

    Purpose: Sign language users recruit physical properties of visual motion to convey linguistic information. Research on American Sign Language (ASL) indicates that signers systematically use kinematic features (e.g., velocity, deceleration) of dominant hand motion for distinguishing specific semantic properties of verb classes in production…

  9. Kinematics of machinery through hyperworks

    CERN Document Server

    Rao, J S

    2011-01-01

    Using animations, this book explains the theory of machines concepts and the evolution of Kinematics. The book adopts HyperWorks MotionSolve to perform the analysis and visualizations, though the book is independent of the requirement of any software.

  10. Essential kinematics for autonomous vehicles

    Science.gov (United States)

    Kelly, Alonzo

    1994-05-01

    A short tutorial on Homogeneous Transforms is presented covering the triple interpretation of a homogeneous transform as an operator, a coordinate frame, and a coordinate transform. The operator transform duality is derived and its use in the Denavit Hartenberg convention is explained. Forward, inverse, and differential kinematics are derived for a simple manipulator to illustrate concepts. A standard set of coordinate frames is proposed for wheeled mobile robots. It is shown that the RPY transform serves the same purpose as the DH matrix in this case. It serves to interface with vehicle position estimation systems of all kinds, to control and model pan/tilt mechanisms and stabilized platforms, and to model the rigid transforms from place to place on the vehicle. Forward and inverse kinematics and the Euler angle rate to the angular velocity transform are derived for the RPY transform. Projective kinematics for ideal video cameras and laser rangefinders, and the imaging Jacobian relating world space and image space is derived. Finally, the kinematics of the Ackerman steer vehicle is presented for reference purposes. This report is both a tutorial and a reference for the transforms used in the RANGER vehicle controller. It is both because the models keep evolving and it was necessary to provide the tools, mechanisms, and discipline required to continue the evolution.

  11. Inverse Kinematics with Closed Form Solution for Denso Robot Manipulator

    OpenAIRE

    Prasetia, Ikhsan Eka; Agustinah, Trihastuti

    2015-01-01

    In this paper, the forward kinematics and inverse kinematics used on the Denso robot manipulator which has a 6-DOF. The forward kinematics will result in the desired position by end-effector, while inverse kinematics produce angel on each joint. Inverse kinematics problem are very difficult, therefor to obtain the solution of inverse kinematics using closed form solution with geometry approach. The simulation result obtained from forward kinematics and inverse kinematics is determining desire...

  12. Kinematic Model of NAO Humanoid Robot

    Directory of Open Access Journals (Sweden)

    Miloš D. Jovanović

    2014-06-01

    Full Text Available This paper presents synthesis of kinematic model of NAO humanoid robot of Aldebaran Robotics. NAO humanoid robot has complex kinematic structure with 25 active degrees of freedom (DOF. Humanoid system is formed through 5 mutually depended kinematic chains. After that we applied standard aspects of kinematic chains synthesis and Denavit-Hartenberg parameters of each of 5 chains of robotic structure were introduced. Also, mutual relationships between chains were described, as well as their physical and structural dependence. Generated kinematic model will be the starting point for further dynamical modeling of NAO humanoid robot and motion synthesis on actual platform.

  13. SPACEBAR: Kinematic design by computer graphics

    Science.gov (United States)

    Ricci, R. J.

    1975-01-01

    The interactive graphics computer program SPACEBAR, conceived to reduce the time and complexity associated with the development of kinematic mechanisms on the design board, was described. This program allows the direct design and analysis of mechanisms right at the terminal screen. All input variables, including linkage geometry, stiffness, and applied loading conditions, can be fed into or changed at the terminal and may be displayed in three dimensions. All mechanism configurations can be cycled through their range of travel and viewed in their various geometric positions. Output data includes geometric positioning in orthogonal coordinates of each node point in the mechanism, velocity and acceleration of the node points, and internal loads and displacements of the node points and linkages. All analysis calculations take at most a few seconds to complete. Output data can be viewed at the scope and also printed at the discretion of the user.

  14. Sex Differences in Tibiocalcaneal Kinematics

    Directory of Open Access Journals (Sweden)

    Sinclair Jonathan

    2014-08-01

    Full Text Available Purpose. Female runners typically suffer more from chronic running injuries than age-matched males, although the exact biome-chanical mechanisms behind the increased susceptibility of female runners are unknown. This study aimed to compare sex differences in tibiocalcaneal kinematics during the stance phase of running. Methods. Twenty male and twenty female participants ran at 4.0 m · s–1. Tibiocalcaneal kinematics were measured using an eight-camera motion analysis system and compared using independent samples t tests. Results. Peak eversion and tibial internal rotation angles were shown to be significantly greater in female runners. Conclusions. based on these observations, it was determined that female runners may be at increased risk from chronic injury development in relation to excessive tibiocalcaneal motions in the coronal and transverse planes.

  15. Kinematic Fitting of Detached Vertices

    Energy Technology Data Exchange (ETDEWEB)

    Mattione, Paul [Rice Univ., Houston, TX (United States)

    2007-05-01

    The eg3 experiment at the Jefferson Lab CLAS detector aims to determine the existence of the $\\Xi_{5}$ pentaquarks and investigate the excited $\\Xi$ states. Specifically, the exotic $\\Xi_{5}^{--}$ pentaquark will be sought by first reconstructing the $\\Xi^{-}$ particle through its weak decays, $\\Xi^{-}\\to\\pi^{-}\\Lambda$ and $\\Lambda\\to\\pi^{-}$. A kinematic fitting routine was developed to reconstruct the detached vertices of these decays, where confidence level cuts on the fits are used to remove background events. Prior to fitting these decays, the exclusive reaction $\\gamma D\\rightarrow pp\\pi^{-}$ was studied in order to correct the track measurements and covariance matrices of the charged particles. The $\\Lambda\\rightarrow p\\pi^{-}$ and $\\Xi^{-}\\to\\pi^{-}\\Lambda$ decays were then investigated to demonstrate that the kinematic fitting routine reconstructs the decaying particles and their detached vertices correctly.

  16. Contact kinematics of biomimetic scales

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Ranajay; Ebrahimi, Hamid; Vaziri, Ashkan, E-mail: vaziri@coe.neu.edu [Department of Mechanical and Industrial Engineering, Northeastern University, Boston, Massachusetts 02115 (United States)

    2014-12-08

    Dermal scales, prevalent across biological groups, considerably boost survival by providing multifunctional advantages. Here, we investigate the nonlinear mechanical effects of biomimetic scale like attachments on the behavior of an elastic substrate brought about by the contact interaction of scales in pure bending using qualitative experiments, analytical models, and detailed finite element (FE) analysis. Our results reveal the existence of three distinct kinematic phases of operation spanning linear, nonlinear, and rigid behavior driven by kinematic interactions of scales. The response of the modified elastic beam strongly depends on the size and spatial overlap of rigid scales. The nonlinearity is perceptible even in relatively small strain regime and without invoking material level complexities of either the scales or the substrate.

  17. Measurement of reed valve kinematics

    Directory of Open Access Journals (Sweden)

    Fenkl Michael

    2016-01-01

    Full Text Available The measurement of key kinematic parameters of a reed valve movement is necessary for the further development of the reed valve system. These parameters are dependent on the geometry and material properties of the valve. As they directly affect the quantity of air flowing around the valve, a simple and easy to implement measurement of various valve configuration based on the air flow has been devised and is described in this paper, along with its technical parameters and drawbacks when evaluating reed valves used in reciprocating air compressors. Results are presented for a specimen of a compressor under examination. All kinematic parameters, and timing of the opening and closing of the valve, obtained from the measurement are presented and discussed.

  18. Pythagoras Theorem and Relativistic Kinematics

    Science.gov (United States)

    Mulaj, Zenun; Dhoqina, Polikron

    2010-01-01

    In two inertial frames that move in a particular direction, may be registered a light signal that propagates in an angle with this direction. Applying Pythagoras theorem and principles of STR in both systems, we can derive all relativistic kinematics relations like the relativity of simultaneity of events, of the time interval, of the length of objects, of the velocity of the material point, Lorentz transformations, Doppler effect and stellar aberration.

  19. Review of water wave kinematics

    Energy Technology Data Exchange (ETDEWEB)

    Sterndorff, M.J.

    1995-03-01

    The present report covers a comprehensive review of water wave kinematics carried out by Danish Hydraulic Institute (DHI) in connection with the EFP`93 project: Dynamics of Mono Tower Platforms (ref. EFP`93, 1313/93-0009). This project is carried out in cooperation with Ramboell, Hannemann and Hoejlund A/S. The main objectives of the project are to develop and verify a method for the determination of the non-linear wave load and the dynamic response of mono tower platforms. One of the characteristics of mono tower platforms is that due to the small water plane area the hydrodynamic loading will be very concentrated. Such platforms may therefore respond strongly and in a highly dynamic manner to short waves and high order components of extreme waves having periods corresponding to the first natural period of the platform. A key element in the hydrodynamic load process is the wave kinematics. The present report is a comprehensive review of recent literature concerning wave theories, wave-current interaction, laboratory experiments, and field measurements of water wave kinematics. The review has been concentrated on non-breaking waves on deep to intermediate water depths. Papers concerning shallow water waves have only been reviewed if they present methods which may be applied for deep to intermediate water waves. (au) EFP-93; 30 refs.

  20. Decoupled Closed-Form Solution for Humanoid Lower Limb Kinematics

    Directory of Open Access Journals (Sweden)

    Alejandro Said

    2015-01-01

    Full Text Available This paper presents an explicit, omnidirectional, analytical, and decoupled closed-form solution for the lower limb kinematics of the humanoid robot NAO. The paper starts by decoupling the position and orientation analysis from the overall Denavit-Hartenberg (DH transformation matrices. Here, the joint activation sequence for the DH matrices is based on the geometry of a triangle. Furthermore, the implementation of a forward and a reversed kinematic analysis for the support and swing phase equations is developed to avoid matrix inversion. The allocation of constant transformations allows the position and orientation end-coordinate systems to be aligned with each other. Also, the redefinition of the DH transformations and the use of constraints allow decoupling the shared DOF between the legs and the torso. Finally, a geometric approach to avoid the singularities during the walking process is indicated. Numerical data is presented along with an experimental implementation to prove the validity of the analytical results.

  1. Caliko: An Inverse Kinematics Software Library Implementation of the FABRIK Algorithm

    OpenAIRE

    Lansley, Alastair; Vamplew, Peter; Smith, Philip; Foale, Cameron

    2016-01-01

    The Caliko library is an implementation of the FABRIK (Forward And Backward Reaching Inverse Kinematics) algorithm written in Java. The inverse kinematics (IK) algorithm is implemented in both 2D and 3D, and incorporates a variety of joint constraints as well as the ability to connect multiple IK chains together in a hierarchy. The library allows for the simple creation and solving of multiple IK chains as well as visualisation of these solutions. It is licensed under the MIT software license...

  2. Kinematics Control and Analysis of Industrial Robot

    Science.gov (United States)

    Zhu, Tongbo; Cai, Fan; Li, Yongmei; Liu, Wei

    2018-03-01

    The robot’s development present situation, basic principle and control system are introduced briefly. Research is mainly focused on the study of the robot’s kinematics and motion control. The structural analysis of a planar articulated robot (SCARA) robot is presented,the coordinate system is established to obtain the position and orientation matrix of the end effector,a method of robot kinematics analysis based on homogeneous transformation method is proposed, and the kinematics solution of the robot is obtained.Establishment of industrial robot’s kinematics equation and formula for positive kinematics by example. Finally,the kinematic analysis of this robot was verified by examples.It provides a basis for structural design and motion control.It has active significance to promote the motion control of industrial robot.

  3. Inverse Kinematic Analysis Of A Quadruped Robot

    Directory of Open Access Journals (Sweden)

    Muhammed Arif Sen

    2017-09-01

    Full Text Available This paper presents an inverse kinematics program of a quadruped robot. The kinematics analysis is main problem in the manipulators and robots. Dynamic and kinematic structures of quadruped robots are very complex compared to industrial and wheeled robots. In this study inverse kinematics solutions for a quadruped robot with 3 degrees of freedom on each leg are presented. Denavit-Hartenberg D-H method are used for the forward kinematic. The inverse kinematic equations obtained by the geometrical and mathematical methods are coded in MATLAB. And thus a program is obtained that calculate the legs joint angles corresponding to desired various orientations of robot and endpoints of legs. Also the program provides the body orientations of robot in graphical form. The angular positions of joints obtained corresponding to desired different orientations of robot and endpoints of legs are given in this study.

  4. Nuclear reaction studies using inverse kinematics

    International Nuclear Information System (INIS)

    Shapira, D.

    1985-01-01

    Reaction studies with reversed kinematics refer to studies of nuclear reactions induced by a heavy projectile colliding with lighter target nuclei. The technique of using reversed kinematics is costly in terms of the available center-of-mass energy. Most of the projectile's energy goes into forward motion of the reaction products in the laboratory system. Examples are presented where the use of reversed kinematics techniques has provided new information on certain reaction processes. A list of kinematic properties and advantages they may afford is shown. Clearly the possible studies listed can be done without using reversed kinematics but because of the difficulty associated with some of these studies they were never performed until more energetic heavier beams have become available and the reversed kinematics technique was utilized

  5. Kinematics of visually-guided eye movements.

    Directory of Open Access Journals (Sweden)

    Bernhard J M Hess

    Full Text Available One of the hallmarks of an eye movement that follows Listing's law is the half-angle rule that says that the angular velocity of the eye tilts by half the angle of eccentricity of the line of sight relative to primary eye position. Since all visually-guided eye movements in the regime of far viewing follow Listing's law (with the head still and upright, the question about its origin is of considerable importance. Here, we provide theoretical and experimental evidence that Listing's law results from a unique motor strategy that allows minimizing ocular torsion while smoothly tracking objects of interest along any path in visual space. The strategy consists in compounding conventional ocular rotations in meridian planes, that is in horizontal, vertical and oblique directions (which are all torsion-free with small linear displacements of the eye in the frontal plane. Such compound rotation-displacements of the eye can explain the kinematic paradox that the fixation point may rotate in one plane while the eye rotates in other planes. Its unique signature is the half-angle law in the position domain, which means that the rotation plane of the eye tilts by half-the angle of gaze eccentricity. We show that this law does not readily generalize to the velocity domain of visually-guided eye movements because the angular eye velocity is the sum of two terms, one associated with rotations in meridian planes and one associated with displacements of the eye in the frontal plane. While the first term does not depend on eye position the second term does depend on eye position. We show that compounded rotation - displacements perfectly predict the average smooth kinematics of the eye during steady- state pursuit in both the position and velocity domain.

  6. Kinematics of visually-guided eye movements.

    Science.gov (United States)

    Hess, Bernhard J M; Thomassen, Jakob S

    2014-01-01

    One of the hallmarks of an eye movement that follows Listing's law is the half-angle rule that says that the angular velocity of the eye tilts by half the angle of eccentricity of the line of sight relative to primary eye position. Since all visually-guided eye movements in the regime of far viewing follow Listing's law (with the head still and upright), the question about its origin is of considerable importance. Here, we provide theoretical and experimental evidence that Listing's law results from a unique motor strategy that allows minimizing ocular torsion while smoothly tracking objects of interest along any path in visual space. The strategy consists in compounding conventional ocular rotations in meridian planes, that is in horizontal, vertical and oblique directions (which are all torsion-free) with small linear displacements of the eye in the frontal plane. Such compound rotation-displacements of the eye can explain the kinematic paradox that the fixation point may rotate in one plane while the eye rotates in other planes. Its unique signature is the half-angle law in the position domain, which means that the rotation plane of the eye tilts by half-the angle of gaze eccentricity. We show that this law does not readily generalize to the velocity domain of visually-guided eye movements because the angular eye velocity is the sum of two terms, one associated with rotations in meridian planes and one associated with displacements of the eye in the frontal plane. While the first term does not depend on eye position the second term does depend on eye position. We show that compounded rotation - displacements perfectly predict the average smooth kinematics of the eye during steady- state pursuit in both the position and velocity domain.

  7. Inverse kinematics of OWI-535 robotic arm

    OpenAIRE

    DEBENEC, PRIMOŽ

    2015-01-01

    The thesis aims to calculate the inverse kinematics for the OWI-535 robotic arm. The calculation of the inverse kinematics determines the joint parameters that provide the right pose of the end effector. The pose consists of the position and orientation, however, we will focus only on the second one. Due to arm limitations, we have created our own type of the calculation of the inverse kinematics. At first we have derived it only theoretically, and then we have transferred the derivation into...

  8. Basic concepts of kinematic-wave models

    Science.gov (United States)

    Miller, J.E.

    1984-01-01

    The kinematic-wave model is one of a number of approximations of the dynamic-wave model. The dynamic-wave model describes onedimensional shallow-water waves (unsteady, gradually varied, openchannel flow). This report provides a basic reference on the theory and applications of the kinematic-wave model and describes the limitations of the model in relation to the other approximations of the dynamic-wave model. In the kinematic-wave approximation, a number of the terms in the equation of motion are assumed to be insignificant. The equation of motion is replaced by an equation describing uniform flow. Thus, the kinematic-wave model is described by the continuity equation and a uniform-flow equation such as the wellknown Chezy or Manning formulas. Kinematic-wave models are applicable to overland flow where lateral inflow is continuously added and is a large part of the total flow. For channel-routing applications, the kinematic-wave model always predicts a steeper wave with less dispersion and attenuation than actually occurs. The effect of the accumulation of errors in the kinematic-wave model shows that the approximations made in the development of the kinematic-wave equations are not generally justified for most channel-routing applications. Modified flow-routing models can be used which help to stop the accumulation of errors that occur when the kinematic-wave model is applied.

  9. Detailed solution to a complex kinematics chain manipulator

    Energy Technology Data Exchange (ETDEWEB)

    March-Leuba, S; Jansen, J F; Kress, R L; Babcock, S M

    1992-01-01

    This paper presents a relatively simple method based on planar geometry to analyze the inverse kinematics for closed kinematics chain (CKC) mechanisms. Although the general problem and method of approach are well defined, the study of the inverse kinematics of a closed-chain mechanism is a very complicated one. The current methodology allows closed-form solutions to be found, if a solution exists, for the displacements and velocities of all manipulator joints. Critical design parameters can be identified and optimized by using symbolic models. This paper will focus on planar closed-chain structures extended with a rotational base. However, with open and CKC mechanisms combined in different planes, the extension to the case is straightforward. Further, real-time algorithms are developed that can be handled by existing microprocessor technology. To clarify the methodology, the Soldier Robot Interface Project (SRIP) manipulator is analyzed, and a graphic simulation is presented as a verification of the results. This manipulator has 17 links, 24 one-degree-of-freedom (DOF) joints, and 7 CKC loops working in a plane and a rotational base, which determine its 3 DOFs. The SRIP manipulator allows a decoupled linear motion along the vertical or horizontal directions using only one of its linear actuators. The symbolic solution for the inverse kinematics allows optimization to be performed to further decouple the Cartesian motions by changing link lengths of the manipulator. The conclusion achieved by the optimization is that only two link lengths need to be changed to tune the manipulator for a perfect decoupling at each area of the workspace.

  10. Detailed solution to a complex kinematics chain manipulator

    International Nuclear Information System (INIS)

    March-Leuba, S.; Jansen, J.F.; Kress, R.L.; Babcock, S.M.

    1992-01-01

    This paper presents a relatively simple method based on planar geometry to analyze the inverse kinematics for closed kinematics chain (CKC) mechanisms. Although the general problem and method of approach are well defined, the study of the inverse kinematics of a closed-chain mechanism is a very complicated one. The current methodology allows closed-form solutions to be found, if a solution exists, for the displacements and velocities of all manipulator joints. Critical design parameters can be identified and optimized by using symbolic models. This paper will focus on planar closed-chain structures extended with a rotational base. However, with open and CKC mechanisms combined in different planes, the extension to the case is straightforward. Further, real-time algorithms are developed that can be handled by existing microprocessor technology. To clarify the methodology, the Soldier Robot Interface Project (SRIP) manipulator is analyzed, and a graphic simulation is presented as a verification of the results. This manipulator has 17 links, 24 one-degree-of-freedom (DOF) joints, and 7 CKC loops working in a plane and a rotational base, which determine its 3 DOFs. The SRIP manipulator allows a decoupled linear motion along the vertical or horizontal directions using only one of its linear actuators. The symbolic solution for the inverse kinematics allows optimization to be performed to further decouple the Cartesian motions by changing link lengths of the manipulator. The conclusion achieved by the optimization is that only two link lengths need to be changed to tune the manipulator for a perfect decoupling at each area of the workspace

  11. Ballistic representation for kinematic access

    Science.gov (United States)

    Alfano, Salvatore

    2011-01-01

    This work uses simple two-body orbital dynamics to initially determine the kinematic access for a ballistic vehicle. Primarily this analysis was developed to assess when a rocket body might conjunct with an orbiting satellite platform. A family of access opportunities can be represented as a volume for a specific rocket relative to its launch platform. Alternately, the opportunities can be represented as a geographical footprint relative to aircraft or satellite position that encompasses all possible launcher locations for a specific rocket. A thrusting rocket is treated as a ballistic vehicle that receives all its energy at launch and follows a coasting trajectory. To do so, the rocket's burnout energy is used to find its equivalent initial velocity for a given launcher's altitude. Three kinematic access solutions are then found that account for spherical Earth rotation. One solution finds the maximum range for an ascent-only trajectory while another solution accommodates a descending trajectory. In addition, the ascent engagement for the descending trajectory is used to depict a rapid access scenario. These preliminary solutions are formulated to address ground-, sea-, or air-launched vehicles.

  12. KINEMATIC ANALYSIS OF MODULAR, TRUSS-BASED MANIPULATOR UNITS

    Energy Technology Data Exchange (ETDEWEB)

    Salerno, R. J.

    1994-06-01

    Decontamination and Dismantling (D&D) activities within the U.S. Department of Energy (DOE) require a long reach manipulator with a large load capacity. Variable Geometry Trusses (VGTs) are a unique class of mechanical structures which allow the advantages of truss structures for large scale applications to be applied to large robotic manipulators. Individual VGT units may be assembled to create a modular, long-reach, truss-type manipulator. Each module of such a manipulator system is either a static truss section or one of several possible VGT geometries. While many potential applications exist for this technology, the present work is largely motivated by the need for generic robotic systems for remote manipulation. A manipulator system based on VGT modules provides several advantages. The reconfigurable nature of the manipulator system allows it to be adapted on site to unforeseen conditions. The kinematic redundancy of the manipulator enables it to work effectively even in a highly obstructed workspace. The parallel structure of the truss modules enables the manipulator to be withdrawn in the event of a structural failure. Finally, the open framework of the modules provides a clear, protected passageway for control and power cabling, waste conveyance, or other services required at the end effector. As is implied in a truss structure, all primary members of a VGT are ideally loaded in pure tension or compression. This results in an extremely stiff and strong manipulator system with minimal overall weight. Careful design of the joints of a VGT is very important to the overall stiffness and accuracy of the structure, as several links (as many as six) are joined together at each joint. The greatest disadvantage to this approach to manipulator design has traditionally been that the kinematics of VGT structures are complex and poorly understood. This report specifically addresses the kinematics of several possible geometries for the individual VGT units. Equations and

  13. 76 FR 5733 - Clothing Allowance

    Science.gov (United States)

    2011-02-02

    ... DEPARTMENT OF VETERANS AFFAIRS 38 CFR Part 3 RIN 2900-AN64 Clothing Allowance AGENCY: Department... to amend its adjudication regulations regarding clothing allowances. The amendment would provide for annual clothing allowances for each qualifying prosthetic or orthopedic appliance worn or used by a...

  14. Fission of highly excited nuclei investigated in complete kinematic measurements

    International Nuclear Information System (INIS)

    Rodriguez-Sanchez, J. L.; Benlliure, J.; Taieb, J.; Avarez-Pol, H.; Audouin, L.; Ayyad, Y.; Belier, G.; Boutoux, G.; Casarejos, E.; Chatillon, A.; Cortina-Gil, D.; Gorbinet, T.; Heinz, A.; Kelic-Heil, A.; Kurz, N.; Laurent, B.; Martin, J. F.; Paradela, C.; Pellereau, E.; Pietras, B.; Prochazka, A.; Ramos, D.; Rodriguez-Tajes, C.; Rossi, D.; Simon, H.; Tassan-Got, L.; Vargas, J.; Voss, B.

    2013-01-01

    Fission is an extremely complex mechanism that requires a dynamical approach to describe the evolution of the process in terms of intrinsic and collective excitations of the nuclear constituents. In order to determine these effects a complex experimental setup was mounted at GSI, which allowed us for the first time the full identification in charge and mass of all fission fragments thanks to a magnetic separation and the use of the inverse kinematic technique. Moreover, we also measured the neutron multiplicities and the light-charged particles emitted in coincidence with fission. These complete kinematic measurements will be used to define sensitive observables to dissipative and transient effects in fission. In this manuscript we present the first results for the total fission cross sections. (authors)

  15. New Methods for Kinematic Modelling and Calibration of Robots

    DEFF Research Database (Denmark)

    Søe-Knudsen, Rune

    2014-01-01

    Improving a robot's accuracy increases its ability to solve certain tasks, and is therefore valuable. Practical ways of achieving this improved accuracy, even after robot repair, is also valuable. In this work, we introduce methods that improve the robot's accuracy and make it possible to maintain...... the accuracy in an easy and accessible way. The required equipment is accessible, since the cost is held to a minimum and can be made with conventional processing equipment. Our first method calibrates the kinematics of a robot using known relative positions measured with the robot itself and a plate...... with holes matching the robot tool flange. The second method calibrates the kinematics using two robots. This method allows the robots to carry out the collection of measurements and the adjustment, by themselves, after the robots have been connected. Furthermore, we also propose a method for restoring...

  16. Kinematically Decoupled Cores in Dwarf (Elliptical) Galaxies

    NARCIS (Netherlands)

    Toloba, E.; Peletier, R. F.; Guhathakurta, P.; van de Ven, G.; Boissier, S.; Boselli, A.; Brok, M. d.; Falcón-Barroso, J.; Hensler, G.; Janz, J.; Laurikainen, E.; Lisker, T.; Paudel, S.; Ryś, A.; Salo, H.

    An overview is given of what we know about the frequency of kinematically decoupled cores in dwarf elliptical galaxies. New observations show that kinematically decoupled cores happen just as often in dwarf elliptical as in ordinary early-type galaxies. This has important consequences for the

  17. Kinematic Analysis 6dof Delta Manipulator

    Directory of Open Access Journals (Sweden)

    Dawid PIETRALA

    2014-12-01

    Full Text Available In the paper the solid and kinematic model of delta type parallel manipulator with six degrees of freedom is proposed. Method of determining the manipulator kinematics equations using the notation of Denavitt – Hartenberg is presented. For given movements of manipulator platform the trajectory of drives are illustrated. Also working space for various platform orientations are showed.

  18. Kinematic analysis of Sculptor Group galaxies

    NARCIS (Netherlands)

    Schoenmakers, RHM; Valtonen, MJ; Flynn, C

    2000-01-01

    An analysis of the kinematics of the five major spiral galaxies in the Sculptor Group is presented. These galaxies are analyzed using the method of harmonic expansion of the velocity field as described in Schoenmakers, Franx and de Zeeuw (1997). Three different types of kinematic distortions were

  19. Kinematic models of extensional structures

    International Nuclear Information System (INIS)

    Groshong, R.H. Jr.

    1990-01-01

    This paper discusses kinematic models that can relate faults of different types and different positions within a single dynamic system and thereby offer the potential to explain the disparate seismic activity characteristic of extensional terrains. The major styles are full grabens, half grabens, domino blocks, and glide-block systems. Half grabens, the most likely models for Basin and Range structure, are formed above a master fault of decreasing dip with depth and a hangingwall that deforms as it passes over the curved fault. Second-order normal faults, typically domino style, accommodate the required hangingwall deformation. According to the author low-angle detachment faults are consistent with the evidence of seismicity only on high-angle faults if the hangingwall of the detachment is broken by multiple half-graben systems

  20. Bat flight: aerodynamics, kinematics and flight morphology.

    Science.gov (United States)

    Hedenström, Anders; Johansson, L Christoffer

    2015-03-01

    Bats evolved the ability of powered flight more than 50 million years ago. The modern bat is an efficient flyer and recent research on bat flight has revealed many intriguing facts. By using particle image velocimetry to visualize wake vortices, both the magnitude and time-history of aerodynamic forces can be estimated. At most speeds the downstroke generates both lift and thrust, whereas the function of the upstroke changes with forward flight speed. At hovering and slow speed bats use a leading edge vortex to enhance the lift beyond that allowed by steady aerodynamics and an inverted wing during the upstroke to further aid weight support. The bat wing and its skeleton exhibit many features and control mechanisms that are presumed to improve flight performance. Whereas bats appear aerodynamically less efficient than birds when it comes to cruising flight, they have the edge over birds when it comes to manoeuvring. There is a direct relationship between kinematics and the aerodynamic performance, but there is still a lack of knowledge about how (and if) the bat controls the movements and shape (planform and camber) of the wing. Considering the relatively few bat species whose aerodynamic tracks have been characterized, there is scope for new discoveries and a need to study species representing more extreme positions in the bat morphospace. © 2015. Published by The Company of Biologists Ltd.

  1. Investigating The Kinematics of Canids and Felids

    Science.gov (United States)

    Sur, D.

    2016-12-01

    For all organisms, metabolic energy is critical for survival. While moving efficiently is a necessity for large carnivores, the influence of kinematics on energy demand remains poorly understood. We measured the kinematics of dogs, wolves, and pumas to detect any differences in their respective energy expenditures. Using 22 kinematic parameters measured on 78 videos, we used one-way ANOVAs and paired T-tests to compare 5 experimental treatments among gaits in dogs (n=11 in 3 breed groups), wolves (n=2), and pumas (n=2). Across the measured parameters, we found greater kinematic similarity than expected among dog breeds and no trend in any of the 22 parameters regarding the effect of steepness on locomotion mechanics. Similarly, treadmill kinematics were nearly identical to those measured during outdoor movement. However, in 3 inches of snow, we observed significant differences (pwolf. When comparing canids (wolves and dogs) to a felid (pumas), we found that pumas and dogs are the most kinematically distinct (differing in 13 of 22 parameters, compared with 5 of 22 for wolves and pumas). Lastly, compared with wolves, walking pumas had larger head angles (p=0.0025), forelimb excursion angles (p=0.0045), and hindlimb excursion angles (p=0.0327). After comparing the energetics of pumas and dogs with their respective kinematics, we noted that less dynamic kinematics result in energy savings. Through tracking the locations and gait behavior of large carnivores, novel sensor technology can reveal how indoor kinematics applies to wild animals and improve the conservation of these species.

  2. Inverse Kinematics With Closed Form Solution For Denso Robot Manipulator

    Directory of Open Access Journals (Sweden)

    Ikhsan Eka Prasetia

    2015-03-01

    Full Text Available In this paper, the forward kinematics and inverse kinematics used on the Denso robot manipulator which has a 6-DOF. The forward kinematics will result in the desired position by end-effector, while inverse kinematics produce angel on each joint. Inverse kinematics problem are very difficult, therefor to obtain the solution of inverse kinematics using closed form solution with geometry approach. The simulation result obtained from forward kinematics and inverse kinematics is determining desired position by Denso robot manipulator. Forward kinematics produce the desired position by the end-effector. Inverse kinematics produce joint angle, where the inverse kinematics produce eight conditions obtained from closed form solution with geometry approach to reach the desired position by the end-effector.

  3. On the Kinematics of Robotic-assisted Minimally Invasive Surgery

    Directory of Open Access Journals (Sweden)

    Pål Johan From

    2013-04-01

    Full Text Available Minimally invasive surgery is characterized by the insertion of the surgical instruments into the human body through small insertion points called trocars, as opposed to open surgery which requires substantial cutting of skin and tissue to give the surgeon direct access to the operating area. To avoid damage to the skin and tissue, zero lateral velocity at the insertion point is crucial. Entering the human body through trocars in this way thus adds constraints to the robot kinematics and the end-effector velocities cannot be found from the joint velocities using the simple relation given by the standard Jacobian matrix. We therefore derive a new Jacobian matrix which gives the relation between the joint variables and the end-effector velocities and at the same time guarantees that the velocity constraints at the insertion point are always satisfied. We denote this new Jacobian the Remote Center of Motion Jacobian Matrix (RCM Jacobian. The main contribution of this paper is that we address the problem at a kinematic level and that we through the RCM Jacobian can guarantee that the insertion point constraints are satisfied which again allows for the controller to be implemented in the end-effector workspace. By eliminating the kinematic constraints from the control loop we can derive the control law in the end-effector space and we are therefore able to apply Cartesian control schemes such as compliant or hybrid control.

  4. A kinematic view of loop closure.

    Science.gov (United States)

    Coutsias, Evangelos A; Seok, Chaok; Jacobson, Matthew P; Dill, Ken A

    2004-03-01

    We consider the problem of loop closure, i.e., of finding the ensemble of possible backbone structures of a chain segment of a protein molecule that is geometrically consistent with preceding and following parts of the chain whose structures are given. We reduce this problem of determining the loop conformations of six torsions to finding the real roots of a 16th degree polynomial in one variable, based on the robotics literature on the kinematics of the equivalent rotator linkage in the most general case of oblique rotators. We provide a simple intuitive view and derivation of the polynomial for the case in which each of the three pair of torsional axes has a common point. Our method generalizes previous work on analytical loop closure in that the torsion angles need not be consecutive, and any rigid intervening segments are allowed between the free torsions. Our approach also allows for a small degree of flexibility in the bond angles and the peptide torsion angles; this substantially enlarges the space of solvable configurations as is demonstrated by an application of the method to the modeling of cyclic pentapeptides. We give further applications to two important problems. First, we show that this analytical loop closure algorithm can be efficiently combined with an existing loop-construction algorithm to sample loops longer than three residues. Second, we show that Monte Carlo minimization is made severalfold more efficient by employing the local moves generated by the loop closure algorithm, when applied to the global minimization of an eight-residue loop. Our loop closure algorithm is freely available at http://dillgroup. ucsf.edu/loop_closure/. Copyright 2004 Wiley Periodicals, Inc. J Comput Chem 25: 510-528, 2004

  5. Robot Kinematics, using Dual Quaternions

    Directory of Open Access Journals (Sweden)

    Mahmoud Gouasmi

    2012-03-01

    Full Text Available From the point of view of classical mechanics, deriving the equations of motion for systems of coupled rigid bodies is regarded as a straightforward procedure: once a suitable set of generalized coordinates and reference frames have been chosen, what remains is to either apply Lagrange’s equations or Newton and Euler’s equations to obtain the differential equations of motion. As the complexity of multibody system increases, the need for more elegant formulation of the equation of motion becomes an issue of paramount importance. Our primary focus is on the kinematic analysis of rigid bodies and serial manipulators (robotic systems  using simultaneously, both homogeneous transformations (4x4 matrices and Dual Quaternions, for the sake of results comparisons (cost,complexity,storage capacity etc. . This paper has been done mainly for educational and peadagogical purposes, hoping that the scientific community will finally adopt and use Dual Quaternions at least when dealing with multibody systems and specially robotics.

  6. A Soft Parallel Kinematic Mechanism.

    Science.gov (United States)

    White, Edward L; Case, Jennifer C; Kramer-Bottiglio, Rebecca

    2018-02-01

    In this article, we describe a novel holonomic soft robotic structure based on a parallel kinematic mechanism. The design is based on the Stewart platform, which uses six sensors and actuators to achieve full six-degree-of-freedom motion. Our design is much less complex than a traditional platform, since it replaces the 12 spherical and universal joints found in a traditional Stewart platform with a single highly deformable elastomer body and flexible actuators. This reduces the total number of parts in the system and simplifies the assembly process. Actuation is achieved through coiled-shape memory alloy actuators. State observation and feedback is accomplished through the use of capacitive elastomer strain gauges. The main structural element is an elastomer joint that provides antagonistic force. We report the response of the actuators and sensors individually, then report the response of the complete assembly. We show that the completed robotic system is able to achieve full position control, and we discuss the limitations associated with using responsive material actuators. We believe that control demonstrated on a single body in this work could be extended to chains of such bodies to create complex soft robots.

  7. Kinematic anharmonicity of internal rotation of molecules

    International Nuclear Information System (INIS)

    Bataev, V.A.; Pupyshev, V.I.; Godunov, I.A.

    2017-01-01

    The methods of analysis the strongly coupled vibrations are proposed for a number of molecules of aromatic and heterocyclic carbonyl (and some others) compounds. The qualitative principles are formulated for molecular systems with a significant kinematic anharmonicity.

  8. Analisys and Choice of the Exoskeleton’s Actuator Kinematic Structure

    Directory of Open Access Journals (Sweden)

    A. A. Vereikin

    2014-01-01

    Full Text Available The urgency of designing of robotic exoskeletons as one of the most prospective means of modern robotics is proved. A literature review concerning the design issues of anthropomorphic walking robots and exoskeletons is performed. Some problems, accompanying the designing process of exoskeleton actuator, are highlighted. Among them synthesis of its tree-like kinematic structure takes leading place. Its complication is explained by the specific human-machine interaction.The problem of exoskeleton actuator kinematic scheme synthesis is formulated and possible approaches to its solution are shown. The paper presents the synthesis results obtained using the software complex CATIA-based means of ergonomic design. It investigates the degrees of freedom of human-operator’s foot, shin, and thigh. And it identifies a number of shortcomings of this software complex associated with the ambiguity to solve the inverse kinematics problem, leading to a significant complication of kinematics synthesis.A model of human lower limb on which further studies of the exoskeleton actuator kinematic scheme, ensuring fulfillment of the human-operator standard movements (squats, kick their feet, bending body, walking, running stairs, etc., are based, is developed in SolidWorks software complex. The reasonability of the exoskeleton kinematic scheme synthesis in software package SolidWorks using anthropometric data from the software complex CATIA, is justified.The proposed method allows to analyze different kinematic schemes of actuator for the stage of conceptual design and to choose the best of them in accordance with established criterions. Thus, the developer receives the final version of the kinematic scheme before the detailed design of the actuator starts, thus significantly reducing its labor costs.

  9. Kinematics analysis of a novel planar parallel manipulator with kinematic redundancy

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Haibo; Guo, Sheng [Beijing Jiaotong University, Beijing (China)

    2017-04-15

    In this paper, a novel planar parallel manipulator with kinematic redundancy is proposed. First, the Degrees of freedom (DOF) of the whole parallel manipulator and the Relative DOF (RDOF) between the moving platform and fixed base are studied. The results indicate that the proposed mechanism is kinematically redundant. Then, the kinematics, Jacobian matrices and workspace of this proposed parallel manipulator with kinematic redundancy are analyzed. Finally, the statics simulation of the proposed parallel manipulator is performed. The obtained stress and displacement distribution can be used to determine the easily destroyed place in the mechanism configurations.

  10. Kinematics analysis of a novel planar parallel manipulator with kinematic redundancy

    International Nuclear Information System (INIS)

    Qu, Haibo; Guo, Sheng

    2017-01-01

    In this paper, a novel planar parallel manipulator with kinematic redundancy is proposed. First, the Degrees of freedom (DOF) of the whole parallel manipulator and the Relative DOF (RDOF) between the moving platform and fixed base are studied. The results indicate that the proposed mechanism is kinematically redundant. Then, the kinematics, Jacobian matrices and workspace of this proposed parallel manipulator with kinematic redundancy are analyzed. Finally, the statics simulation of the proposed parallel manipulator is performed. The obtained stress and displacement distribution can be used to determine the easily destroyed place in the mechanism configurations

  11. Heavy baryon spectroscopy with relativistic kinematics

    International Nuclear Information System (INIS)

    Valcarce, A.; Garcilazo, H.; Vijande, J.

    2014-01-01

    We present a comparative Faddeev study of heavy baryon spectroscopy with nonrelativistic and relativistic kinematics. We show results for different standard hyperfine interactions with both kinematics in an attempt to learn about the light quark dynamics. We highlight the properties of particular states accessible in nowadays laboratories that would help in discriminating between different dynamical models. The advance in the knowledge of light quark dynamics is a key tool for the understanding of the existence of exotic hadrons.

  12. Dynamic Control of Kinematically Redundant Robotic Manipulators

    Directory of Open Access Journals (Sweden)

    Erling Lunde

    1987-07-01

    Full Text Available Several methods for task space control of kinematically redundant manipulators have been proposed in the literature. Most of these methods are based on a kinematic analysis of the manipulator. In this paper we propose a control algorithm in which we are especially concerned with the manipulator dynamics. The algorithm is particularly well suited for the class of redundant manipulators consisting of a relatively small manipulator mounted on a larger positioning part.

  13. Kinematics of Laying an Automated Weapon System

    Science.gov (United States)

    2017-07-19

    UNCLASSIFIED UNCLASSIFIED AD-E403 899 Technical Report ARWSE-TR-16024 KINEMATICS OF LAYING AN AUTOMATED WEAPON SYSTEM ...2017 2. REPORT TYPE Final 3. DATES COVERED (From – To) 4. TITLE AND SUBTITLE KINEMATICS OF LAYING AN AUTOMATED WEAPON SYSTEM 5a. CONTRACT...NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) U.S. Army ARDEC, WSEC Weapons Systems & Technology Directorate (RDAR-WSW-I) Picatinny

  14. 76 FR 70883 - Clothing Allowance

    Science.gov (United States)

    2011-11-16

    ...), Compensation Service, Veterans Benefits Administration, Department of Veterans Affairs, 810 Vermont Avenue NW... limited knee movement when walking'' which causes shoes to wear out faster. VA makes no change based on... that multiple appliances might allow the award of multiple benefits.'' That decision provides no basis...

  15. Collecting shoulder kinematics with electromagnetic tracking systems and digital inclinometers: A review.

    Science.gov (United States)

    Hannah, Daniel C; Scibek, Jason S

    2015-11-18

    The shoulder complex presents unique challenges for measuring motion as the scapula, unlike any other bony segment in the body, glides and rotates underneath layers of soft tissue and skin. The ability for clinicians and researchers to collect meaningful kinematic data is dependent on the reliability and validity of the instrumentation utilized. The aim of this study was to review the relevant literature pertaining to the reliability and validity of electromagnetic tracking systems (ETS) and digital inclinometers for assessing shoulder complex motion. Advances in technology have led to the development of biomechanical instrumentation, like ETS, that allow for the collection of three-dimensional kinematic data. The existing evidence has demonstrated that ETS are reliable and valid instruments for collecting static and dynamic kinematic data of the shoulder complex. Similarly, digital inclinometers have become increasingly popular among clinicians due to their cost effectiveness and practical use in the clinical setting. The existing evidence supports the use of digital inclinometers for the collection of shoulder complex kinematics as these instruments have been demonstrated to yield acceptable reliability and validity. While digital inclinometers pose a disadvantage to ETS regarding accuracy, precision, and are limited to two-dimensional and static measurements, this instrument provides clinically meaningful data that allow clinicians and researchers the ability to measure, monitor, and compare shoulder complex kinematics.

  16. Computing broadband accelerograms using kinematic rupture modeling

    International Nuclear Information System (INIS)

    Ruiz Paredes, J.A.

    2007-05-01

    In order to make the broadband kinematic rupture modeling more realistic with respect to dynamic modeling, physical constraints are added to the rupture parameters. To improve the slip velocity function (SVF) modeling, an evolution of the k -2 source model is proposed, which consists to decompose the slip as a sum of sub-events by band of k. This model yields to SVF close to the solution proposed by Kostrov for a crack, while preserving the spectral characteristics of the radiated wave field, i.e. a w 2 model with spectral amplitudes at high frequency scaled to the coefficient of directivity C d . To better control the directivity effects, a composite source description is combined with a scaling law defining the extent of the nucleation area for each sub-event. The resulting model allows to reduce the apparent coefficient of directivity to a fraction of C d , as well as to reproduce the standard deviation of the new empirical attenuation relationships proposed for Japan. To make source models more realistic, a variable rupture velocity in agreement with the physics of the rupture must be considered. The followed approach that is based on an analytical relation between the fracture energy, the slip and the rupture velocity, leads to higher values of the peak ground acceleration in the vicinity of the fault. Finally, to better account for the interaction of the wave field with the geological medium, a semi-empirical methodology is developed combining a composite source model with empirical Green functions, and is applied to the Yamaguchi, M w 5.9 earthquake. The modeled synthetics reproduce satisfactorily well the observed main characteristics of ground motions. (author)

  17. Stellar kinematics across the Hubble sequence in the CALIFA survey : general properties and aperture corrections

    NARCIS (Netherlands)

    Falcón-Barroso, J.; Lyubenova, M.; van de Ven, G.; Mendez-Abreu, J.; Aguerri, J. A. L.; García-Lorenzo, B.; Bekeraité, S.; Sánchez, S. F.; Husemann, B.; García-Benito, R.; Mast, D.; Walcher, C. J.; Zibetti, S.; Barrera-Ballesteros, J. K.; Galbany, L.; Sánchez-Blázquez, P.; Singh, R.; van den Bosch, R. C. E.; Wild, V.; Zhu, L.; Bland-Hawthorn, J.; Cid Fernandes, R.; de Lorenzo-Cáceres, A.; Gallazzi, A.; González Delgado, R. M.; Marino, R. A.; Márquez, I.; Pérez, E.; Pérez, I.; Roth, M. M.; Rosales-Ortega, F. F.; Ruiz-Lara, T.; Wisotzki, L.; Ziegler, B.; Califa Collaboration,

    We present the stellar kinematic maps of a large sample of galaxies from the integral-field spectroscopic survey CALIFA. The sample comprises 300 galaxies displaying a wide range of morphologies across the Hubble sequence, from ellipticals to late-type spirals. This dataset allows us to

  18. Caliko: An Inverse Kinematics Software Library Implementation of the FABRIK Algorithm

    Directory of Open Access Journals (Sweden)

    Alastair Lansley

    2016-09-01

    Full Text Available The Caliko library is an implementation of the FABRIK (Forward And Backward Reaching Inverse Kinematics algorithm written in Java. The inverse kinematics (IK algorithm is implemented in both 2D and 3D, and incorporates a variety of joint constraints as well as the ability to connect multiple IK chains together in a hierarchy. The library allows for the simple creation and solving of multiple IK chains as well as visualisation of these solutions. It is licensed under the MIT software license and the source code is freely available for use and modification at: https://github.com/feduni/caliko

  19. Kinematics and design of a portable and wearable exoskeleton for hand rehabilitation.

    Science.gov (United States)

    Cempini, Marco; De Rossi, Stefano Marco Maria; Lenzi, Tommaso; Cortese, Mario; Giovacchini, Francesco; Vitiello, Nicola; Carrozza, Maria Chiara

    2013-06-01

    We present the kinematic design and actuation mechanics of a wearable exoskeleton for hand rehabilitation of post-stroke. Our design method is focused on achieving maximum safety, comfort and reliability in the interaction, and allowing different users to wear the device with no manual regulations. In particular, we propose a kinematic and actuation solution for the index finger flexion/extension, which leaves full movement freedom on the abduction-adduction plane. This paper presents a detailed kineto-static analysis of the system and a first prototype of the device.

  20. Inverse Kinematics of Concentric Tube Steerable Needles.

    Science.gov (United States)

    Sears, Patrick; Dupont, Pierre E

    2007-01-01

    Prior papers have introduced steerable needles composed of precurved concentric tubes. The curvature and extent of these needles can be controlled by the relative rotation and translation of the individual tubes. Under certain assumptions on the geometry and design of these needles, the forward kinematics problem can be solved in closed form by means of algebraic equations. The inverse kinematics problem, however, is not as straightforward owing to the nonlinear map between relative tube displacements and needle tip configuration as well as to the multiplicity of solutions as the number of tubes increases. This paper presents a general approach to solving the inverse kinematics problem using a pseudoinverse solution together with gradients of nullspace potential functions to enforce geometric and mechanical constraints.

  1. Kinematic and Elastostatic Design Optimisation of the 3-DOF Gantry-Tau Parallel Kinematic Manipulator

    Directory of Open Access Journals (Sweden)

    Ilya Tyapin

    2009-04-01

    Full Text Available One of the main advantages of the Gantry-Tau machine is a large accessible workspace/footprint ratio compared to many other parallel machines. The Gantry-Tau improves this ration further by allowing a change of assembly mode without internal link collisions or collisions between the links and end-effector. The reconfigurable Gantry-Tau kinematic design obtained by multi-objective optimisation according to this paper gives the following features: 3-D workspace/footprint ratio is more than 3.19, lowest Cartesian stiffness in the workspace is $5N/mu m$ and no link collisions detected. The optimisation parameters are the support frame lengths, the actuator positions and the robot's arm lengths. The results comparison between the evolutionary complex search algorithm and gradient-based method used for the Gantry-Tau design in the past is also presented in this paper. The detailed statics model analysis of the Gantry-Tau based on a functionally dependency is presented in this paper for the first time. Both the statics model and complex search algorithm may be applied for other 3-DOF Hexapods without major changes. The existing lab prototype of the Gantry-Tau was assembled and completed at the University of Agder, Norway.

  2. Kinematics and Control of Robot Manipulators

    Science.gov (United States)

    Paden, Bradley Evan

    This dissertation focuses on the kinematics and control of robot manipulators. The contribution to kinematics is a fundamental theorem on the design of manipulators with six revolute joints. The theorem states, roughly speaking, that manipulators which have six revolute joints and are modeled after the human arm are optimal and essentially unique. In developing the mathematical framework to prove this theorem, we define precisely the notions of length of a manipulator, well-connected-workspace, and work-volume. We contribute to control a set of analysis techniques for the design of variable structure (sliding mode) controllers for manipulators. The organization of the dissertation is the following. After introductory remarks in chapter one, the group of proper rigid motions, G, is introduced in chapter two. The tangent bundle of G is introduced and it is shown that the velocity of a rigid body can be represented by an element in the Lie algebra of G (commonly called a twist). Further, rigid motions which are exponentials of twists are used to describe four commonly occurring subproblems in robot kinematics. In chapter three, the exponentials of twists are used to write the forward kinematic map of robot manipulators and the subproblems of chapter two are used to solve the Stanford manipulator and an elbow manipulator. Chapter four focuses on manipulator singularities. Twist coordinates are used to find critical points of the forward kinematic map. The contribution to kinematics is contained in chapter five where a mathematical framework for studying the relationship between the design of 6R manipulators and their performance is developed. Chapter seven contains the contribution to control. The work of A. F. Filippov on differential equations with discontinuous right-hand-side and the work of F. H. Clarke on generalized gradients are combined to obtain a calculus for analyzing nonsmooth gradient systems. The techniques developed are applied to design a simple

  3. Linking synchronized flow and kinematic waves

    OpenAIRE

    LAVAL, J

    2005-01-01

    This paper shows that including the e®ects of lane-changing activity in kinematic wave theory reveals the physical mechanisms and reproduces the main empirical features that motivated Kerner's three-phase theory. This is shown using a hybrid representation of tra±c °ow where lane changes are treated as discrete particles with realistic accelerations embedded in a continuous multilane kinematic wave stream. We show that this parsimonious four-parameter model reproduces the three phases identi...

  4. Towards Extending Forward Kinematic Models on Hyper-Redundant Manipulator to Cooperative Bionic Arms

    Science.gov (United States)

    Singh, Inderjeet; Lakhal, Othman; Merzouki, Rochdi

    2017-01-01

    Forward Kinematics is a stepping stone towards finding an inverse solution and subsequently a dynamic model of a robot. Hence a study and comparison of various Forward Kinematic Models (FKMs) is necessary for robot design. This paper deals with comparison of three FKMs on the same hyper-redundant Compact Bionic Handling Assistant (CBHA) manipulator under same conditions. The aim of this study is to project on modeling cooperative bionic manipulators. Two of these methods are quantitative methods, Arc Geometry HTM (Homogeneous Transformation Matrix) Method and Dual Quaternion Method, while the other one is Hybrid Method which uses both quantitative as well as qualitative approach. The methods are compared theoretically and experimental results are discussed to add further insight to the comparison. HTM is the widely used and accepted technique, is taken as reference and trajectory deviation in other techniques are compared with respect to HTM. Which method allows obtaining an accurate kinematic behavior of the CBHA, controlled in the real-time.

  5. End-Effector Position Analysis Using Forward Kinematics For 5 Dof Pravak Robot Arm

    Directory of Open Access Journals (Sweden)

    Jolly Atit Shah

    2013-03-01

    Full Text Available Automatic control of the robotic manipulator involves study of kinematics and dynamics as a major issue. This paper involves the kinematic analysis of a Pravak Robot arm which is used for doing successful robotic manipulation task in its workspace. The Pravak Robot Arm is a 5-DOF robot having all the joints revolute. The kinematics problem is defined as the transformation from the Cartesian space to the joint space and vice versa. In this study the Denavit- Hartenberg (D-H model is used to model robot links and joints. Pravak Robot Arm is a simple and safe robotic system designed for laboratory training and research applications. This robot allows to gain theoretical and practical experience in robotics, automation and control systems. The MATLAB R2007 is used to analyse end effectors position for a set of joint parameter.

  6. A self-calibrating robot based upon a virtual machine model of parallel kinematics

    DEFF Research Database (Denmark)

    Pedersen, David Bue; Eiríksson, Eyþór Rúnar; Hansen, Hans Nørgaard

    2016-01-01

    a virtual machine of the kinematics system, built on principles from geometrical metrology. Relevant mathematically non-trivial deviations to the ideal machine are identified and decomposed into elemental deviations. From these deviations, a routine is added to a physical machine tool, which allows......A delta-type parallel kinematics system for Additive Manufacturing has been created, which through a probing system can recognise its geometrical deviations from nominal and compensate for these in the driving inverse kinematic model of the machine. Novelty is that this model is derived from...... it to recognise its own geometry by probing the vertical offset from tool point to the machine table, at positions in the horizontal plane. After automatic calibration the positioning error of the machine tool was reduced from an initial error after its assembly of ±170 µm to a calibrated error of ±3 µm...

  7. A kinematic study on (unintentional imitation in bottlenose dolphins

    Directory of Open Access Journals (Sweden)

    Luisa eSartori

    2015-08-01

    Full Text Available The aim of the present study was to investigate the effect of observing other’s movements on subsequent performance in bottlenose dolphins. The imitative ability of non-human animals has intrigued a number of researchers. So far, however, studies in dolphins have been confined to intentional imitation concerned with the explicit request to imitate other agents. In the absence of instruction to imitate, do dolphins (unintentionally replicate other’s movement features? To test this, dolphins were filmed while reaching and touching a stimulus before and after observing another dolphin (i.e., model performing the same action. All videos were reviewed and segmented in order to extract the relevant movements. A marker was inserted post-hoc via software on the videos upon the anatomical landmark of interest (i.e. rostrum and was tracked throughout the time course of the movement sequence. The movement was analyzed using an in-house software developed to perform two-dimensional (2D post-hoc kinematic analysis. The results indicate that dolphins’ kinematics is sensitive to other’s movement features. Movements performed for the ‘visuomotor priming’ condition were characterized by a kinematic pattern similar to that performed by the observed dolphin (i.e., model. Addressing the issue of spontaneous imitation in bottlenose dolphins might allow ascertaining whether the potential or impulse to produce an imitative action is generated, not just when they intend to imitate, but whenever they watch another conspecific’s behavior. In closing, this will clarify whether motor representational capacity is a by-product of factors specific to humans or whether more general characteristics such as processes of associative learning prompted by high level of encephalization could help to explain the evolution of this ability.

  8. The Glasgow-Maastricht foot model, evaluation of a 26 segment kinematic model of the foot.

    Science.gov (United States)

    Oosterwaal, Michiel; Carbes, Sylvain; Telfer, Scott; Woodburn, James; Tørholm, Søren; Al-Munajjed, Amir A; van Rhijn, Lodewijk; Meijer, Kenneth

    2016-01-01

    Accurately measuring of intrinsic foot kinematics using skin mounted markers is difficult, limited in part by the physical dimensions of the foot. Existing kinematic foot models solve this problem by combining multiple bones into idealized rigid segments. This study presents a novel foot model that allows the motion of the 26 bones to be individually estimated via a combination of partial joint constraints and coupling the motion of separate joints using kinematic rhythms. Segmented CT data from one healthy subject was used to create a template Glasgow-Maastricht foot model (GM-model). Following this, the template was scaled to produce subject-specific models for five additional healthy participants using a surface scan of the foot and ankle. Forty-three skin mounted markers, mainly positioned around the foot and ankle, were used to capture the stance phase of the right foot of the six healthy participants during walking. The GM-model was then applied to calculate the intrinsic foot kinematics. Distinct motion patterns where found for all joints. The variability in outcome depended on the location of the joint, with reasonable results for sagittal plane motions and poor results for transverse plane motions. The results of the GM-model were comparable with existing literature, including bone pin studies, with respect to the range of motion, motion pattern and timing of the motion in the studied joints. This novel model is the most complete kinematic model to date. Further evaluation of the model is warranted.

  9. The kinematics of machinery outlines of a theory of machines

    CERN Document Server

    Reuleaux, Franz

    2012-01-01

    A classic on the kinematics of machinery, this volume was written by the Father of Kinematics. Reuleaux writes with authority and precision, developing the subject from its fundamentals. 450 figures. 1876 edition.

  10. Coordinate transformations, orthographic projections, and robot kinematics

    International Nuclear Information System (INIS)

    Crochetiere, W.J.

    1984-01-01

    Humans do not consciously think of moving each of their joints while they move their hands from one place to another. Likewise, robot arms can be commanded to move about in cartesian space without the need to address the individual joints. To do this, the direct and inverse kinematic equations of any robot arm must be derived. The direct kinematic equations uniquely transform the joint positions into the position (and orientation) of the hand, whereas the inverse kinematic equations transform the position (and orientation) of the hand into joint positions. The derivation of the inverse kinematic equations for any particular robot is a difficult problem which may have more than one solution. In this paper, these equations are derived for a six degree of freedom robot arm. A combination of matrix operations to perform coordinate rotations, and trigonometry within the appropriate orthographic projects to perform coordinate translations is employed. This complementary approach yields a solution which is more easily obtained, and also more easily visualized. The resulting solution was programmed into a real-time computer as a part of a higher level software system to control the motion of the arm

  11. Right-handed currents at kinematic endpoint

    Indian Academy of Sciences (India)

    Rusa Mandal

    2017-10-09

    Oct 9, 2017 ... kinematic endpoint. RUSA MANDAL1, ANIRBAN KARAN1, ABINASH KUMAR NAYAK1, RAHUL SINHA1,∗ and TOM BROWDER2. 1The Institute of Mathematical Sciences, HBNI, Taramani, Chennai 600 113, India. 2Department of Physics and Astronomy, University of Hawaii, Honolulu, HI 96822, USA. ∗.

  12. Assessment of multi class kinematic wave models

    NARCIS (Netherlands)

    Van Wageningen-Kessels, F.L.M.; Van Lint, J.W.C.; Vuik, C.; Hoogendoorn, S.P.

    2012-01-01

    In the last decade many multi class kinematic wave (MCKW) traffic ow models have been proposed. MCKW models introduce heterogeneity among vehicles and drivers. For example, they take into account differences in (maximum) velocities and driving style. Nevertheless, the models are macroscopic and the

  13. The kinematic algebras from the scattering equations

    International Nuclear Information System (INIS)

    Monteiro, Ricardo; O’Connell, Donal

    2014-01-01

    We study kinematic algebras associated to the recently proposed scattering equations, which arise in the description of the scattering of massless particles. In particular, we describe the role that these algebras play in the BCJ duality between colour and kinematics in gauge theory, and its relation to gravity. We find that the scattering equations are a consistency condition for a self-dual-type vertex which is associated to each solution of those equations. We also identify an extension of the anti-self-dual vertex, such that the two vertices are not conjugate in general. Both vertices correspond to the structure constants of Lie algebras. We give a prescription for the use of the generators of these Lie algebras in trivalent graphs that leads to a natural set of BCJ numerators. In particular, we write BCJ numerators for each contribution to the amplitude associated to a solution of the scattering equations. This leads to a decomposition of the determinant of a certain kinematic matrix, which appears naturally in the amplitudes, in terms of trivalent graphs. We also present the kinematic analogues of colour traces, according to these algebras, and the associated decomposition of that determinant

  14. Constrained tri-sphere kinematic positioning system

    Science.gov (United States)

    Viola, Robert J

    2010-12-14

    A scalable and adaptable, six-degree-of-freedom, kinematic positioning system is described. The system can position objects supported on top of, or suspended from, jacks comprising constrained joints. The system is compatible with extreme low temperature or high vacuum environments. When constant adjustment is not required a removable motor unit is available.

  15. Compound nucleus studies withy reverse kinematics

    International Nuclear Information System (INIS)

    Moretto, L.G.

    1985-06-01

    Reverse kinematics reactions are used to demonstrate the compound nucleus origin of intermediate mass particles at low energies and the extension of the same mechanism at higher energies. No evidence has appeared in our energy range for liquid-vapor equilibrium or cold fragmentation mechanisms. 11 refs., 12 figs

  16. Action experience changes attention to kinematic cues

    Directory of Open Access Journals (Sweden)

    Courtney eFilippi

    2016-02-01

    Full Text Available The current study used remote corneal reflection eye-tracking to examine the relationship between motor experience and action anticipation in 13-month-old infants. To measure online anticipation of actions infants watched videos where the actor’s hand provided kinematic information (in its orientation about the type of object that the actor was going to reach for. The actor’s hand orientation either matched the orientation of a rod (congruent cue or did not match the orientation of the rod (incongruent cue. To examine relations between motor experience and action anticipation, we used a 2 (reach first vs. observe first x 2 (congruent kinematic cue vs. incongruent kinematic cue between-subjects design. We show that 13-month-old infants in the observe first condition spontaneously generate rapid online visual predictions to congruent hand orientation cues and do not visually anticipate when presented incongruent cues. We further demonstrate that the speed that these infants generate predictions to congruent motor cues is correlated with their own ability to pre-shape their hands. Finally, we demonstrate that following reaching experience, infants generate rapid predictions to both congruent and incongruent hand shape cues—suggesting that short-term experience changes attention to kinematics.

  17. Circadian rhythms in handwriting kinematics and legibility

    NARCIS (Netherlands)

    Jasper, Isabelle; Gordijn, Marijke; Haeussler, Andreas; Hermsdoerfer, Joachim

    The aim of the present study was to analyze the circadian rhythmicity in handwriting kinematics and legibility and to compare the performance between Dutch and German writers. Two subject groups underwent a 40 h sleep deprivation protocol under Constant Routine conditions either in Groningen (10

  18. Advanced control schemes and kinematic analysis for a kinematically redundant 7 DOF manipulator

    Science.gov (United States)

    Nguyen, Charles C.; Zhou, Zhen-Lei

    1990-01-01

    The kinematic analysis and control of a kinematically redundant manipulator is addressed. The manipulator is the slave arm of a telerobot system recently built at Goddard Space Flight Center (GSFC) to serve as a testbed for investigating research issues in telerobotics. A forward kinematic transformation is developed in its most simplified form, suitable for real-time control applications, and the manipulator Jacobian is derived using the vector cross product method. Using the developed forward kinematic transformation and quaternion representation of orientation matrices, we perform computer simulation to evaluate the efficiency of the Jacobian in converting joint velocities into Cartesian velocities and to investigate the accuracy of Jacobian pseudo-inverse for various sampling times. The equivalence between Cartesian velocities and quaternion is also verified using computer simulation. Three control schemes are proposed and discussed for controlling the motion of the slave arm end-effector.

  19. Relating backprojection images to kinematics and dynamic source models

    Science.gov (United States)

    Yin, J.; Denolle, M.

    2017-12-01

    Backprojection (BP) of teleseismic P waves is a method widely used to study the evolution of earthquake radiation and is particularly effective for large earthquakes. We can harness details on the spatiotemporal evolution of the rupture process from waveform similarity or coherency. A direct relation between these kinematic observations to earthquake physics is critical. Theoretical analysis indicates that high-frequency bursts can be related to abrupt changes in rupture velocity (e.g. stopping of the rupture or kinks on the fault, e.g. Madariaga, 1976; Madariaga et al., 2006). Moreover, the BP images are thought to be equivalent to either slip or slip rate on the fault, provided that the Green's functions from the sources to the receivers are incoherent delta functions (Fukuhata et al., 2014). Furthermore, recent studies propose that the frequency dependent features of BP results can reflect the stress status, frictional and/or geometrical heterogeneity on the fault surface (e.g. Huang et al., 2012; Lay et al., 2012; Yao et al., 2013; Yin et al., 2016, etc.). With this promising background, we attempt to relate the BP results and earthquake source process through kinematic and dynamic source models. We build synthetic seismic waveforms and trace them back to the fault surface using synthetic backprojection. We carry the 3D kinematic source models using Crempien and Archuleta (2014) and the 2D kinematic models using FDMap (Dunham et al., 2011). By varying the source models such as the friction laws and fault geometries, we directly compare the BP results with the ground truth earthquake sources and further explore the possible relation to the source properties. To simplify our problem and exclude the potential effects from complex earth structure, our tests are carried out in a purely elastic whole space, allowing us to solve analytically for the far-field body waves. From these systematical tests and comparisons, we aim at building a comprehensive relation between

  20. Motor resonance facilitates movement execution: an ERP and kinematic study

    Directory of Open Access Journals (Sweden)

    Mathilde eMénoret

    2013-10-01

    Full Text Available Action observation, simulation and execution share neural mechanisms that allow for a common motor representation. It is known that when these overlapping mechanisms are simultaneously activated by action observation and execution, motor performance is influenced by observation and vice versa. To understand the neural dynamics underlying this influence and to measure how variations in brain activity impact the precise kinematics of motor behaviour, we coupled kinematics and electrophysiological recordings of participants while they performed and observed congruent or non-congruent actions or during action execution alone. We found that movement velocities and the trajectory deviations of the executed actions increased during the observation of congruent actions compared to the observation of non-congruent actions or action execution alone. This facilitation was also discernible in the motor-related potentials of the participants; the motor-related potentials were transiently more negative in the congruent condition around the onset of the executed movement, which occurred 300 ms after the onset of the observed movement. This facilitation seemed to depend not only on spatial congruency but also on the optimal temporal relationship of the observation and execution events.

  1. Using robotics in kinematics classes: exploring braking and stopping distances

    Science.gov (United States)

    Brockington, Guilherme; Schivani, Milton; Barscevicius, Cesar; Raquel, Talita; Pietrocola, Maurício

    2018-03-01

    Research in the field of physics teaching has revealed high school students’ difficulties in establishing relations between kinematic equations and real movements. Moreover, there are well-known and significant challenges in their comprehension of graphic language content. Thus, this article explores a didactic activity which utilized robotics in order to investigate significant aspects of kinematics, gathering data and performing analyses and descriptions via graphs and mathematical equations which were indispensable for the analysis of the phenomena in question. Traffic safety appears as a main theme, with particular emphasis on the distinction between braking and stopping distances in harsh conditions, as observed in the robot vehicle’s tires and track. This active-learning investigation allows students to identify significant differences between the average value of the initial empirical braking position and that of the vehicle’s programmed braking position, enabling them to more deeply comprehend the relations between mathematical and graphic representations of this real phenomenon and the phenomenon itself, thereby providing a sense of accuracy to this study.

  2. The Maiden Voyage of a Kinematics Robot

    Science.gov (United States)

    Greenwolfe, Matthew L.

    2015-04-01

    In a Montessori preschool classroom, students work independently on tasks that absorb their attention in part because the apparatus are carefully designed to make mistakes directly observable and limit exploration to one aspect or dimension. Control of error inheres in the apparatus itself, so that teacher intervention can be minimal.1 Inspired by this example, I created a robotic kinematics apparatus that also shapes the inquiry experience. Students program the robot by drawing kinematic graphs on a computer and then observe its motion. Exploration is at once limited to constant velocity and constant acceleration motion, yet open to complex multi-segment examples difficult to achieve in the lab in other ways. The robot precisely and reliably produces the motion described by the students' graphs, so that the apparatus itself provides immediate visual feedback about whether their understanding is correct as they are free to explore within the hard-coded limits. In particular, the kinematic robot enables hands-on study of multi-segment constant velocity situations, which lays a far stronger foundation for the study of accelerated motion. When correction is anonymous—just between one group of lab partners and their robot—students using the kinematic robot tend to flow right back to work because they view the correction as an integral part of the inquiry learning process. By contrast, when correction occurs by the teacher and/or in public (e.g., returning a graded assignment or pointing out student misconceptions during class), students all too often treat the event as the endpoint to inquiry. Furthermore, quantitative evidence shows a large gain from pre-test to post-test scores using the Test of Understanding Graphs in Kinematics (TUG-K).

  3. Upper Limb Assessment in Tetraplegia: Clinical, Functional and Kinematic Correlations

    Science.gov (United States)

    Cacho, Enio Walker Azevedo; de Oliveira, Roberta; Ortolan, Rodrigo L.; Varoto, Renato; Cliquet, Alberto

    2011-01-01

    The aim of this study was to correlate clinical and functional evaluations with kinematic variables of upper limp reach-to-grasp movement in patients with tetraplegia. Twenty chronic patients were selected to perform reach-to-grasp kinematic assessment using a target placed at a distance equal to the arm's length. Kinematic variables (hand peak…

  4. Learning Kinematics with a V-Scope: A Case Study.

    Science.gov (United States)

    Trumper, Ricardo

    1997-01-01

    Studies the effect of V-Scope activities on the performance of 11th-grade students in analyzing kinematics graphs. Students were challenged to construct different kinds of graphs using their own movements as well as the motion of a dynamics cart. Results indicate that the V-Scope kinematics laboratory activities can promote kinematics concepts and…

  5. Validation and Structural Analysis of the Kinematics Concept Test

    Science.gov (United States)

    Lichtenberger, A.; Wagner, C.; Hofer, S. I.; Stem, E.; Vaterlaus, A.

    2017-01-01

    The kinematics concept test (KCT) is a multiple-choice test designed to evaluate students' conceptual understanding of kinematics at the high school level. The test comprises 49 multiple-choice items about velocity and acceleration, which are based on seven kinematic concepts and which make use of three different representations. In the first part…

  6. KINEMATICS AND DYNAMICS MODELS OF CYLINDRICAL ROLLER BEARING OF RAILWAY TRANSPORT

    Directory of Open Access Journals (Sweden)

    A. V. Gaydamaka

    2014-05-01

    Full Text Available Purpose. Lack of kinematics models and imperfection of the known dynamics models of the roller bearings of railway rolling stock axle-boxes do not allow designing the optimal structure of bearing cages, providing the required service life and reliability of bearing units of wheel sets for cars and locomotives. The studies of kinematics and dynamics of roller bearings of axle boxes for cars and locomotives and modeling of their parts interaction to create the analytical method of bearing cages calculation are necessary. Methodology. This purpose has been achieved due to the modeling of kinematics of the ideal (without gaps and real (taking account the gaps, manufacturing and installation errors bearings, substantiation of the transfer mechanism of motion from the rollers to bearing cage, modeling the dynamics of rolling, research of interaction forces of the rollers with bearing cage. Findings. It is established that the kinematics of ideal bearing is determined by the contact deformations of the rollers and rings, when the kinematics of real bearing depends mainly on the side gaps in the windows of the bearing cage. On the basis of studies of the real bearing kinematics the dynamics models of the rollers and bearing cage interaction were constructed. The conducted studies of kinematics and dynamics of rolling bearings have changed our view of them as of the planetary mechanism, explained the reason of bearing cage loading, and confirmed the possibility of destruction during operation. Originality. It was first proposed a mechanism for motion transfer from the rollers to the bearing cage of roller bearings, consisting in that the side gap in the bearing cage window is reduced gradually multiple of the number of rollers of radial loading area according to the bearing cage motion. The models of roller bearing dynamics, which allow calculating the interaction forces of parts for all modes of operation, were improved. Practical value. Use of the

  7. Morpho-kinematic properties of field S0 bulges in the CALIFA survey

    Science.gov (United States)

    Méndez-Abreu, J.; Aguerri, J. A. L.; Falcón-Barroso, J.; Ruiz-Lara, T.; Sánchez-Menguiano, L.; de Lorenzo-Cáceres, A.; Costantin, L.; Catalán-Torrecilla, C.; Zhu, L.; Sánchez-Blazquez, P.; Florido, E.; Corsini, E. M.; Wild, V.; Lyubenova, M.; van de Ven, G.; Sánchez, S. F.; Bland-Hawthorn, J.; Galbany, L.; García-Benito, R.; García-Lorenzo, B.; González Delgado, R. M.; López-Sánchez, A. R.; Marino, R. A.; Márquez, I.; Ziegler, B.; Califa Collaboration

    2018-02-01

    We study a sample of 28 S0 galaxies extracted from the integral field spectroscopic (IFS) survey Calar Alto Legacy Integral Field Area. We combine an accurate two-dimensional (2D) multicomponent photometric decomposition with the IFS kinematic properties of their bulges to understand their formation scenario. Our final sample is representative of S0s with high stellar masses (M⋆/M⊙ > 1010). They lay mainly on the red sequence and live in relatively isolated environments similar to that of the field and loose groups. We use our 2D photometric decomposition to define the size and photometric properties of the bulges, as well as their location within the galaxies. We perform mock spectroscopic simulations mimicking our observed galaxies to quantify the impact of the underlying disc on our bulge kinematic measurements (λ and v/σ). We compare our bulge corrected kinematic measurements with the results from Schwarzschild dynamical modelling. The good agreement confirms the robustness of our results and allows us to use bulge deprojected values of λ and v/σ. We find that the photometric (n and B/T) and kinematic (v/σ and λ) properties of our field S0 bulges are not correlated. We demonstrate that this morpho-kinematic decoupling is intrinsic to the bulges and it is not due to projection effects. We conclude that photometric diagnostics to separate different types of bulges (disc-like versus classical) might not be useful for S0 galaxies. The morpho-kinematics properties of S0 bulges derived in this paper suggest that they are mainly formed by dissipational processes happening at high redshift, but dedicated high-resolution simulations are necessary to better identify their origin.

  8. On the General Analytical Solution of the Kinematic Cosserat Equations

    KAUST Repository

    Michels, Dominik L.

    2016-09-01

    Based on a Lie symmetry analysis, we construct a closed form solution to the kinematic part of the (partial differential) Cosserat equations describing the mechanical behavior of elastic rods. The solution depends on two arbitrary analytical vector functions and is analytical everywhere except a certain domain of the independent variables in which one of the arbitrary vector functions satisfies a simple explicitly given algebraic relation. As our main theoretical result, in addition to the construction of the solution, we proof its generality. Based on this observation, a hybrid semi-analytical solver for highly viscous two-way coupled fluid-rod problems is developed which allows for the interactive high-fidelity simulations of flagellated microswimmers as a result of a substantial reduction of the numerical stiffness.

  9. The spallation in reverse kinematics: what for a coincidence measurement?

    International Nuclear Information System (INIS)

    Ducret, J.E.

    2006-07-01

    The Spaladin installation has been designed to study spallation reactions in reverse kinematics. Furthermore, the heavy and light fragments are detected by coincidence which allows us to get an instantaneous picture of the reaction at a level of accuracy better than that obtained through inclusive measurement. The first part is dedicated to the theoretical description of the different mechanisms involved in the spallation reactions. In the second part we describe the Spaladin installation and report some results on the reaction: Fe 56 + p at an energy of 1 GeV/nucleon. In the third part we expose the performance of the installation through its simulation with the Geant-IV model. We present a study about the sensitivity of the Spaladin installation to theoretical predictions. The fourth part is dedicated to the future experiments that will be performed with the Spaladin installation. (A.C.)

  10. Control of Redundant Kinematic Degrees of Freedom in a Closed-Loop Brain-Machine Interface.

    Science.gov (United States)

    Moorman, Helene G; Gowda, Suraj; Carmena, Jose M

    2017-06-01

    Brain-machine interface (BMI) systems use signals acquired from the brain to directly control the movement of an actuator, such as a computer cursor or a robotic arm, with the goal of restoring motor function lost due to injury or disease of the nervous system. In BMIs with kinematically redundant actuators, the combination of the task goals and the system under neural control can allow for many equally optimal task solutions. The extent to which kinematically redundant degrees of freedom (DOFs) in a BMI system may be under direct neural control is unknown. To address this question, a Kalman filter was used to decode single- and multi-unit cortical neural activity of two macaque monkeys into the joint velocities of a virtual four-link kinematic chain. Subjects completed movements of the chain's endpoint to instructed target locations within a two-dimensional plane. This system was kinematically redundant for an endpoint movement task, as four DOFs were used to manipulate the 2-D endpoint position. Both subjects successfully performed the task and improved with practice by producing faster endpoint velocity control signals. Kinematic redundancy allowed null movements whereby the individual links of the chain could move in a way that cancels out and does not result in endpoint movement. As the subjects became more proficient at controlling the chain, the amount of null movement also increased. Task performance suffered when the links of the kinematic chain were hidden and only the endpoint was visible. Furthermore, all four DOFs of the joint-velocity control space exhibited task-relevant modulation. The relative usage of each DOF depended on the configuration of the chain, and trials in which the less-prominent DOFs were utilized also had better task performance. Overall, these results indicate that the subjects incorporated the redundant components of the control space into their control strategy. Future BMI systems with kinematic redundancy, such as exoskeletal

  11. Kinematics of the symbiotic system R Aqr

    Science.gov (United States)

    Navarro, S.; Corral, L. J.; Steffen, W.

    2014-04-01

    We present the results of the kinematical analysis of the symbiotic system R Aqr. We obtained high dispersion spectra with the MES spectrograph at the 2.1 m telescope of San Pedro Mártir (MEZCAL). The used filter were Ha + [NII], (λc = 6575Å, Δλ = 90Å). We analyse the [NII] λλ6583 line. When the observations are compared with previous ones by Solf (1992) we detected an important change in the projected velocities of the observed knots, supporting the idea of a precessing jet. We are working also in a 3-D kinematic model for the object using the measured velocities and the state of the model is presented.

  12. The kinematic advantage of electric cars

    Science.gov (United States)

    Meyn, Jan-Peter

    2015-11-01

    Acceleration of a common car with with a turbocharged diesel engine is compared to the same type with an electric motor in terms of kinematics. Starting from a state of rest, the electric car reaches a distant spot earlier than the diesel car, even though the latter has a better specification for engine power and average acceleration from 0 to 100 km h-1. A three phase model of acceleration as a function of time fits the data of the electric car accurately. The first phase is a quadratic growth of acceleration in time. It is shown that the tenfold higher coefficient for the first phase accounts for most of the kinematic advantage of the electric car.

  13. Kinematic measurements using an infrared sensor

    International Nuclear Information System (INIS)

    Marinho, F; Paulucci, L

    2016-01-01

    The use of an infrared sensor as a new alternative to measure position as a function of time in kinematic experiments was investigated using a microcontroller as the data acquisition and control device. These are versatile sensors that offer advantages over typical ultrasound devices. The setup described in this paper enables students to develop their own experiments, promoting opportunities for learning physical concepts such as the different types of forces that can act on a body (gravitational, elastic, drag, etc) and the resulting types of movements with good sensitivity within the 4–30 cm range. As a proof of concept we also present the application of a prototype designed to record the kinematics of mass-spring systems. (paper)

  14. Directed Neutron Beams From Inverse Kinematic Reactions

    Science.gov (United States)

    Vanhoy, J. R.; Guardala, N. A.; Glass, G. A.

    2011-06-01

    Kinematic focusing of an emitted fairly mono-energetic neutron beam by the use of inverse-kinematic reactions, i.e. where the projectile mass is greater than the target atom's mass, can provide for the utilization of a significant fraction of the fast neutron yield and also provide for a safer radiation environment. We examine the merit of various neutron production reactions and consider the practicalities of producing the primary beam using the suitable accelerator technologies. Preliminary progress at the NSWC-Carderock Positive Ion Accelerator Facility is described. Possible important applications for this type of neutron-based system can be both advanced medical imaging techniques and active "stand-off" interrogation of contraband items.

  15. 6th International Workshop on Computational Kinematics

    CERN Document Server

    Gracia, Alba

    2014-01-01

    Computational kinematics is an enthralling area of science with a rich spectrum of problems at the junction of mechanics, robotics, computer science, mathematics, and computer graphics. The covered topics include design and optimization of cable-driven robots, analysis of parallel manipulators, motion planning, numerical methods for mechanism calibration and optimization, geometric approaches to mechanism analysis and design, synthesis of mechanisms, kinematical issues in biomechanics, construction of novel mechanical devices, as well as detection and treatment of singularities. The results should be of interest for practicing and research engineers as well as Ph.D. students from the fields of mechanical and electrical engineering, computer science, and computer graphics. Indexed in Conference Proceedings Citation Index- Science (CPCI-S).

  16. Surface growth kinematics via local curve evolution

    KAUST Repository

    Moulton, Derek E.

    2012-11-18

    A mathematical framework is developed to model the kinematics of surface growth for objects that can be generated by evolving a curve in space, such as seashells and horns. Growth is dictated by a growth velocity vector field defined at every point on a generating curve. A local orthonormal basis is attached to each point of the generating curve and the velocity field is given in terms of the local coordinate directions, leading to a fully local and elegant mathematical structure. Several examples of increasing complexity are provided, and we demonstrate how biologically relevant structures such as logarithmic shells and horns emerge as analytical solutions of the kinematics equations with a small number of parameters that can be linked to the underlying growth process. Direct access to cell tracks and local orientation enables for connections to be made to the underlying growth process. © 2012 Springer-Verlag Berlin Heidelberg.

  17. On the kinematic age of RZ Psc

    Science.gov (United States)

    Potravnov, I. S.; Grinin, V. P.

    2013-11-01

    RZ Psc belongs to the family of young UX Ori stars whose photometric activity is due to strong extinction variations in the circumstellar disks surrounding them. However, in contrast to all the remaining stars of this type, no evidence of youth has been detected for RZ Psc until recently. A rough estimate of the star's kinematic age was made for the first time in our previous paper (Grinin et al. 2010). It shows that RZ Psc is intermediate in its evolutionary status between young stars in Orion and stars with debris disks. In this paper, we provide a refined estimate of the kinematic age for the star confirming this conclusion. According to this estimate, the age of RZ Psc is approximately 25 ± 5 Myr at M * = 1 M ⊙.

  18. Kinematics of swimming garter snakes (Thamnophis sirtalis).

    Science.gov (United States)

    Munk, Yonatan

    2008-06-01

    We investigate the kinematics of swimming garter snakes (Thamnophis sirtalis) using a novel nonlinear regression-based digitization method to establish quantitative statistical support for non-constant wavelengths in the undulatory pattern exhibited by swimming snakes. We find that in swimming snakes, the growth of the amplitude of the propulsive wave head-to-tail is strongly correlated (p < 0.005) with the head-to-tail growth in the wavelength. We investigate correlations between kinematic parameters and steady swimming speed, and find a very strong positive correlation between swimming speed and undulation frequency. We furthermore find a statistically well-supported positive correlation between swimming speed and both the initial amplitude of the propulsive wave at the head and the degree of amplitude growth from head to tail.

  19. Kinematic Diversity in Rorqual Whale Feeding Mechanisms.

    Science.gov (United States)

    Cade, David E; Friedlaender, Ari S; Calambokidis, John; Goldbogen, Jeremy A

    2016-10-10

    Rorqual whales exhibit an extreme lunge filter-feeding strategy characterized by acceleration to high speed and engulfment of a large volume of prey-laden water [1-4]. Although tagging studies have quantified the kinematics of lunge feeding, the timing of engulfment relative to body acceleration has been modeled conflictingly because it could never be directly measured [5-7]. The temporal coordination of these processes has a major impact on the hydrodynamics and energetics of this high-cost feeding strategy [5-9]. If engulfment and body acceleration are temporally distinct, the overall cost of this dynamic feeding event would be minimized. However, greater temporal overlap of these two phases would theoretically result in higher drag and greater energetic costs. To address this discrepancy, we used animal-borne synchronized video and 3D movement sensors to quantify the kinematics of both the skull and body during feeding events. Krill-feeding blue and humpback whales exhibited temporally distinct acceleration and engulfment phases, with humpback whales reaching maximum gape earlier than blue whales. In these whales, engulfment coincided largely with body deceleration; however, humpback whales pursuing more agile fish demonstrated highly variable coordination of skull and body kinematics in the context of complex prey-herding techniques. These data suggest that rorquals modulate the coordination of acceleration and engulfment to optimize foraging efficiency by minimizing locomotor costs and maximizing prey capture. Moreover, this newfound kinematic diversity observed among rorquals indicates that the energetic efficiency of foraging is driven both by the whale's engulfment capacity and the comparative locomotor capabilities of predator and prey. VIDEO ABSTRACT. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. A new kinematical definition of orbital eccentricity

    Directory of Open Access Journals (Sweden)

    Ninković S.

    2009-01-01

    Full Text Available A new concept of orbital eccentricity is given. The dimensionless quantities proposed in the present paper to serve as orbital eccentricities have a kinematical nature. The purpose is to use them in describing the motion for the case of three-dimensional orbits. A comparison done for nearly planar orbits shows that the values of the eccentricities proposed here do not differ significantly from those corresponding to the eccentricities of geometric nature usually applied.

  1. Kinematics of Hooke universal joint robot wrists

    Science.gov (United States)

    Mckinney, William S., Jr.

    1988-01-01

    The singularity problem associated with wrist mechanisms commonly found on industrial manipulators can be alleviated by redesigning the wrist so that it functions as a three-axis gimbal system. This paper discussess the kinematics of gimbal robot wrists made of one and two Hooke universal joints. Derivations of the resolved rate motion control equations for the single and double Hooke universal joint wrists are presented using the three-axis gimbal system as a theoretical wrist model.

  2. Kinematic Analysis Of Tricept Parallel Manipulator

    Directory of Open Access Journals (Sweden)

    Mir Amin Hosseini

    2012-01-01

    Full Text Available Parallel manipulators consist of fixed and moving platforms connected to each other with some actuated links. They have some significant advantages over their serial counterparts. While, they suffer from relatively small workspaces, complex kinematics relations and highly singular points within their workspaces. In this paper, forward kinematics of Tricept parallel manipulator is solved analytically and its workspace optimization is performed. This parallel manipulator has a complex degree of freedom, therefore leads to dimensional in-homogeneous Jacobian matrices. Thus, we divide some entries of the Jacobian by units of length, thereby producing a new Jacobian that is dimensionally homogeneous. Moreover, its workspace is parameterized using some design parameters. Then, using GA method, the workspace is optimized subjects to some geometric constraints. Finally, dexterity of the design is evaluated. Keywords- Kinematic, Workspace, Singularity, TriceptABSTRAK - Manipulator selari terdiri daripada platform tetap dan bergerak yang bersambung antara satu sama lain dengan beberapa pautan bergerak. Manipulator selari mempunyai beberapa kebaikan tertentu dibandingkan dengan yang bersamaan dengannya. Walaupun ia mempunyai ruang kerja yang sempit, hubungan kinematik kompleks dan titik tunggal tinggi dalam linkungan ruang kerjanya. Dalam kajian ini, kinematik ke hadapan manipulator selari Tricept diselesaikan secara analisa dan pengoptimuman ruang kerja dijalankan. Manipulator selari ini mempunyai darjah kebebasan yang kompleks, yang menyebabkan ia mendorong kepada kehomogenan dimensi matriks Jacobian. Catatan Jacobian dibahagikan kepada unit panjang, dimana ia menghasilkan Jacobian baru yang homogen dimensinya. Tambahan, ruang kerjanya diparameterkan dengan menggunakan beberapa parameter reka bentuk. Kemudian, dengan kaedah GA, ruang kerja mengoptimakan subjek kepada beberapa kekangan geometrik. Akhirnya, kecakatan reka bentuk dinilaikan

  3. Dwarf elliptical galaxies with kinematically decoupled cores

    Science.gov (United States)

    De Rijcke, S.; Dejonghe, H.; Zeilinger, W. W.; Hau, G. K. T.

    2004-10-01

    We present, for the first time, photometric and kinematical evidence, obtained with FORS2 on the VLT, for the existence of kinematically decoupled cores (KDCs) in two dwarf elliptical galaxies; FS76 in the NGC 5044 group and FS373 in the NGC 3258 group. Both kinematically peculiar subcomponents rotate in the same sense as the main body of their host galaxy but betray their presence by a pronounced bump in the rotation velocity profiles at a radius of about 1''. The KDC in FS76 rotates at 10 ± 3 km s-1, with the host galaxy rotating at 15 ± 6 km s-1; the KDC in FS373 has a rotation velocity of 6 ± 2 km s-1 while the galaxy itself rotates at 20 ± 5 km s-1. FS373 has a very complex rotation velocity profile with the velocity changing sign at 1.5 Re. The velocity and velocity dispersion profiles of FS76 are asymmetric at larger radii. This could be caused by a past gravitational interaction with the giant elliptical NGC 5044, which is at a projected distance of 50 kpc. We argue that these decoupled cores are most likely not produced by mergers in a group or cluster environment because of the prohibitively large relative velocities. A plausible alternative is offered by flyby interactions between a dwarf elliptical or its disky progenitor and a massive galaxy. The tidal forces during an interaction at the relative velocities and impact parameters typical for a group environment exert a torque on the dwarf galaxy that, according to analytical estimates, transfers enough angular momentum to its stellar envelope to explain the observed peculiar kinematics.

  4. Efficient Kinematic Computations For 7-DOF Manipulators

    Science.gov (United States)

    Seraji, Homayoun; Long, Mark K.; Kreutz-Delgado, Kenneth

    1994-01-01

    Efficient algorithms for forward kinematic mappings of seven-degree-of-freedom (7-DOF) robotic manipulator having revolute joints developed on basis of representation of redundant DOF in terms of parameter called "arm angle." Continuing effort to exploit redundancy in manipulator according to concept of basic and additional tasks. Concept also discussed in "Configuration-Control Scheme Copes With Singularities" (NPO-18556) and "Increasing the Dexterity of Redundant Robots" (NPO-17801).

  5. New Kinematical Constraints on Cosmic Acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Rapetti, David; Allen, Steve W.; Amin, Mustafa A.; Blandford, Roger; /-KIPAC, Menlo Park

    2007-05-25

    We present and employ a new kinematical approach to ''dark energy'' studies. We construct models in terms of the dimensionless second and third derivatives of the scale factor a(t) with respect to cosmic time t, namely the present-day value of the deceleration parameter q{sub 0} and the cosmic jerk parameter, j(t). An elegant feature of this parameterization is that all {Lambda}CDM models have j(t)=1 (constant), which facilitates simple tests for departures from the {Lambda}CDM paradigm. Applying our model to redshift-independent distance measurements, from type Ia supernovae and X-ray cluster gas mass fraction measurements, we obtain clear statistical evidence for a late time transition from a decelerating to an accelerating phase. For a flat model with constant jerk, j(t)=j, we measure q{sub 0}=-0.81 {+-} 0.14 and j=2.16 +0.81 -0.75, results that are consistent with {Lambda}CDM at about the 1{sigma} confidence level. In comparison to dynamical analyses, the kinematical approach uses a different model set and employs a minimum of prior information, being independent of any particular gravity theory. The results obtained with this new approach therefore provide important additional information and we argue that both kinematical and dynamical techniques should be employed in future dark energy studies, where possible.

  6. Kinematic gait analyses in healthy Golden Retrievers

    Directory of Open Access Journals (Sweden)

    Gabriela C.A. Silva

    2014-12-01

    Full Text Available Kinematic analysis relates to the relative movement between rigid bodies and finds application in gait analysis and other body movements, interpretation of their data when there is change, determines the choice of treatment to be instituted. The objective of this study was to standardize the march of Dog Golden Retriever Healthy to assist in the diagnosis and treatment of musculoskeletal disorders. We used a kinematic analysis system to analyse the gait of seven dogs Golden Retriever, female, aged between 2 and 4 years, weighing 21.5 to 28 kg, clinically normal. Flexion and extension were described for shoulder, elbow, carpal, hip, femorotibialis and tarsal joints. The gait was characterized lateral and had accepted hypothesis of normality for all variables, except for the stance of hip and elbow, considering a confidence level of 95%, significance level α = 0.05. Variations have been attributed to displacement of the stripes during movement and the duplicated number of reviews. The kinematic analysis proved to be a consistent method of evaluation of the movement during canine gait and the data can be used in the diagnosis and evaluation of canine gait in comparison to other studies and treatment of dogs with musculoskeletal disorders.

  7. Scapula Kinematics of Youth Baseball Players

    Directory of Open Access Journals (Sweden)

    Oliver Gretchen

    2015-12-01

    Full Text Available Literature has revealed the importance of quantifying resting scapular posture in overhead athletes as well as quantifying scapular kinematics during dynamic movement. Prior to this project much of the attention in throwing research had been focused on the position of the humerus without description of the positioning of the scapula. Therefore, it was the purpose of this study to present scapular kinematics during pitching in youth baseball players. Twenty-five youth baseball players (age 11.3 + 1.0 years; body height 152.4 + 9.0 cm; body mass 47.5 + 11.3 kg, with no history of injury, participated in the study. Scapular kinematics at the events of maximum humeral external rotation (MER and maximum humeral internal rotation (MIR during the pitching motion were assessed three-dimensionally while pitching fastballs for strikes. Results revealed that at the event of MER, the scapula was in a position of retraction, upward rotation and a posterior tilt. While at the event of MIR, the scapula was protracted, upward rotated and tilted anteriorly.

  8. What COP and Kinematic Parameters Better Characterize Postural Control in Standing Balance Tasks?

    Science.gov (United States)

    Caballero, Carla; Barbado, David; Moreno, Francisco Javier

    2015-01-01

    The authors' aim was to determine which variables allow for the characterization of motor balance behavior. Traditional measures and nonlinear measures of center of pressure (COP; n = 30) and kinematics (n = 10) were tested in their absolute and relative consistency in a 30-s standing balance task protocol under stable and unstable conditions. Regarding COP variables, mean velocity (mVel), permutation entropy (PE) and detrended fluctuation analysis (DFA) exhibited high consistency between trials and ranked individuals more accurately compare with other metrics. In the kinematic signal mVel, PE and DFA had good intrasession reliability values in unstable conditions. Overall, the intrasession reliability values were better in the unstable condition than in the stable condition and the measures calculated using derived data had better intrasession reliability values. In conclusion, mVel, PE, and DFA allow for the good characterization of motor balance behavior in a simplified protocol where velocity time series are analyzed.

  9. GNSS Precise Kinematic Positioning for Multiple Kinematic Stations Based on A Priori Distance Constraints.

    Science.gov (United States)

    He, Kaifei; Xu, Tianhe; Förste, Christoph; Petrovic, Svetozar; Barthelmes, Franz; Jiang, Nan; Flechtner, Frank

    2016-04-01

    When applying the Global Navigation Satellite System (GNSS) for precise kinematic positioning in airborne and shipborne gravimetry, multiple GNSS receiving equipment is often fixed mounted on the kinematic platform carrying the gravimetry instrumentation. Thus, the distances among these GNSS antennas are known and invariant. This information can be used to improve the accuracy and reliability of the state estimates. For this purpose, the known distances between the antennas are applied as a priori constraints within the state parameters adjustment. These constraints are introduced in such a way that their accuracy is taken into account. To test this approach, GNSS data of a Baltic Sea shipborne gravimetric campaign have been used. The results of our study show that an application of distance constraints improves the accuracy of the GNSS kinematic positioning, for example, by about 4 mm for the radial component.

  10. The SOFIA experiment: Measurement of 236U fission fragment yields in inverse kinematics

    Directory of Open Access Journals (Sweden)

    Grente L.

    2016-01-01

    Full Text Available The SOFIA (Studies On FIssion with Aladin experiment aims at measuring fission-fragments isotopic yields with high accuracy using inverse kinematics at relativistic energies. This experimental technique allows to fully identify the fission fragments in nuclear charge and mass number, thus providing very accurate isotopic yields for low energy fission of a large variety of fissioning systems. This report focuses on the latest results obtained with this set-up concerning electromagnetic-induced fission of 236U.

  11. A black-hole mass measurement from molecular gas kinematics in NGC4526.

    Science.gov (United States)

    Davis, Timothy A; Bureau, Martin; Cappellari, Michele; Sarzi, Marc; Blitz, Leo

    2013-02-21

    The masses of the supermassive black holes found in galaxy bulges are correlated with a multitude of galaxy properties, leading to suggestions that galaxies and black holes may evolve together. The number of reliably measured black-hole masses is small, and the number of methods for measuring them is limited, holding back attempts to understand this co-evolution. Directly measuring black-hole masses is currently possible with stellar kinematics (in early-type galaxies), ionized-gas kinematics (in some spiral and early-type galaxies) and in rare objects that have central maser emission. Here we report that by modelling the effect of a black hole on the kinematics of molecular gas it is possible to fit interferometric observations of CO emission and thereby accurately estimate black-hole masses. We study the dynamics of the gas in the early-type galaxy NGC 4526, and obtain a best fit that requires the presence of a central dark object of 4.5(+4.2)(-3.1) × 10(8) solar masses (3σ confidence limit). With the next-generation millimetre-wavelength interferometers these observations could be reproduced in galaxies out to 75 megaparsecs in less than 5 hours of observing time. The use of molecular gas as a kinematic tracer should thus allow one to estimate black-hole masses in hundreds of galaxies in the local Universe, many more than are accessible with current techniques.

  12. Kinematic analysis of hip and knee rotation and other contributors to ballet turnout.

    Science.gov (United States)

    Quanbeck, Amy E; Russell, Jeffrey A; Handley, Sara C; Quanbeck, Deborah S

    2017-02-01

    Turnout, or external rotation (ER) of the lower extremities, is essential in ballet. The purpose of this study was to utilise physical examination and a biomechanical method for obtaining functional kinematic data using hip and knee joint centres to identify the relative turnout contributions from hip rotation, femoral anteversion, knee rotation, tibial torsion, and other sources. Ten female dancers received a lower extremity alignment assessment, including passive hip rotation, femoral anteversion, tibial torsion, weightbearing foot alignment, and Beighton hypermobility score. Next, turnout was assessed using plantar pressure plots and three-dimensional motion analysis; participants performed turnout to ballet first position on both a plantar pressure mat and friction-reducing discs. A retro-reflective functional marker motion capture system mapped the lower extremities and hip and knee joint centres. Mean total turnout was 129±15.7° via plantar pressure plots and 135±17.8° via kinematics. Bilateral hip ER during turnout was 49±10.2° (36% of total turnout). Bilateral knee ER during turnout was 41±5.9° (32% of total turnout). Hip ER contribution to total turnout measured kinematically was less than expected compared to other studies, where hip ER was determined without functional kinematic data. Knee ER contributed substantially more turnout than expected or previously reported. This analysis method allows precise assessment of turnout contributors.

  13. Kinematics modeling and simulation of an autonomous omni-directional mobile robot

    Directory of Open Access Journals (Sweden)

    Daniel Garcia Sillas

    2015-05-01

    Full Text Available Although robotics has progressed to the extent that it has become relatively accessible with low-cost projects, there is still a need to create models that accurately represent the physical behavior of a robot. Creating a completely virtual platform allows us to test behavior algorithms such as those implemented using artificial intelligence, and additionally, it enables us to find potential problems in the physical design of the robot. The present work describes a methodology for the construction of a kinematic model and a simulation of the autonomous robot, specifically of an omni-directional wheeled robot. This paper presents the kinematic model development and its implementation using several tools. The result is a model that follows the kinematics of a triangular omni-directional mobile wheeled robot, which is then tested by using a 3D model imported from 3D Studio® and Matlab® for the simulation. The environment used for the experiment is very close to the real environment and reflects the kinematic characteristics of the robot.

  14. Numerical simulation for the design analysis of kinematic Stirling engines

    International Nuclear Information System (INIS)

    Araoz, Joseph A.; Salomon, Marianne; Alejo, Lucio; Fransson, Torsten H.

    2015-01-01

    Highlights: • A thermodynamic analysis for kinematic Stirling engines was presented. • The analysis integrated thermal, mechanical and thermodynamic interactions. • The analyses considered geometrical and operational parameters. • The results allowed to map the performance of the engine. • The analysis allow the design assessment of Stirling engines. - Abstract: The Stirling engine is a closed-cycle regenerative system that presents good theoretical properties. These include a high thermodynamic efficiency, low emissions levels thanks to a controlled external heat source, and multi-fuel capability among others. However, the performance of actual prototypes largely differs from the mentioned theoretical potential. Actual engine prototypes present low electrical power outputs and high energy losses. These are mainly attributed to the complex interaction between the different components of the engine, and the challenging heat transfer and fluid dynamics requirements. Furthermore, the integration of the engine into decentralized energy systems such as the Combined Heat and Power systems (CHP) entails additional complications. These has increased the need for engineering tools that could assess design improvements, considering a broader range of parameters that would influence the engine performance when integrated within overall systems. Following this trend, the current work aimed to implement an analysis that could integrate the thermodynamics, and the thermal and mechanical interactions that influence the performance of kinematic Stirling engines. In particular for their use in Combined Heat and Power systems. The mentioned analysis was applied for the study of an engine prototype that presented very low experimental performance. The numerical methodology was selected for the identification of possible causes that limited the performance. This analysis is based on a second order Stirling engine model that was previously developed and validated. The

  15. The Geneva-Copenhagen survey of the Solar neighbourhood: Ages, metallicities, and kinematic properties of 14,000 F and G dwarfs

    OpenAIRE

    Nordstrom, B.; Mayor, M.; Andersen, J.; Holmberg, J.; Pont, F.; Jorgensen, B. R.; Olsen, E. H.; Udry, S.; Mowlavi, N.

    2004-01-01

    We present and discuss new determinations of metallicity, rotation, age,kinematics, and Galactic orbits for a complete, magnitude-limited, andkinematically unbiased sample of 16 682 nearby F and G dwarf stars. Our∼63 000 new, accurate radial-velocity observations for nearly 13 500stars allow identification of most of the binary stars in the sampleand, together with published uvbyβ photometry, Hipparcosparallaxes, Tycho-2 proper motions, and a few earlier radial velocities,complete the kinemat...

  16. Inverse Kinematics Solution and Verification of 4-DOF Hydraulic Manipulator

    Science.gov (United States)

    Chao, Zhiqiang; Wang, Fei; Zhang, Chuanqing; Li, Huaying

    2017-10-01

    Aimed at four degree of freedom (DOF) hydraulic manipulator, an inverse kinematics solution is proposed from Cartesian space to drive space based on geometrical method. To the structural and diver characteristics of the manipulator, a forward kinematics is conducted by using D-H method. The position and orientation of manipulator’s end-effector can be obtained under the kinematics constraint. By analyzing the structure, the solution of inverse kinematics of manipulator can be obtained, and the conversion between drive space and joint space can be got through the sport’s mechanism kinematics. In order to meet the need of motion planning and control of the manipulator, the inverse kinematics and conversion are validated based on simulation.

  17. Modifying the test of understanding graphs in kinematics

    Science.gov (United States)

    Zavala, Genaro; Tejeda, Santa; Barniol, Pablo; Beichner, Robert J.

    2017-12-01

    In this article, we present several modifications to the Test of Understanding Graphs in Kinematics. The most significant changes are (i) the addition and removal of items to achieve parallelism in the objectives (dimensions) of the test, thus allowing comparisons of students' performance that were not possible with the original version, and (ii) changes to the distractors of some of the original items that represent the most frequent alternative conceptions. The final modified version (after an iterative process involving four administrations of test variations over two years) was administered to 471 students of an introductory university physics course at a large private university in Mexico. When analyzing the final modified version of the test it was found that the added items satisfied the statistical tests of difficulty, discriminatory power, and reliability; also, that the great majority of the modified distractors were effective in terms of their frequency selection and discriminatory power; and, that the final modified version of the test satisfied the reliability and discriminatory power criteria as well as the original test. Here, we also show the use of the new version of the test, presenting a new analysis of students' understanding not possible to do before with the original version of the test, specifically regarding the objectives and items that in the new version meet parallelisms. Finally, in the PhysPort project (physport.org), we present the final modified version of the test. It can be used by teachers and researchers to assess students' understanding of graphs in kinematics, as well as their learning about them.

  18. Three-dimensional kinematics of capuchin monkey bipedalism.

    Science.gov (United States)

    Demes, Brigitte

    2011-05-01

    Capuchin monkeys are known to use bipedalism when transporting food items and tools. The bipedal gait of two capuchin monkeys in the laboratory was studied with three-dimensional kinematics. Capuchins progress bipedally with a bent-hip, bent-knee gait. The knee collapses into flexion during stance and the hip drops in height. The knee is also highly flexed during swing to allow the foot which is plantarflexed to clear the ground. The forefoot makes first contact at touchdown. Stride frequency is high, and stride length and limb excursion low. Hind limb retraction is limited, presumably to reduce the pitch moment of the forward-leaning trunk. Unlike human bipedalism, the bipedal gait of capuchins is not a vaulting gait, and energy recovery from pendulum-like exchanges is unlikely. It extends into speeds at which humans and other animals run, but without a human-like gait transition. In this respect it resembles avian bipedal gaits. It remains to be tested whether energy is recovered through cyclic elastic storage and release as in bipedal birds at higher speeds. Capuchin bipedalism has many features in common with the facultative bipedalism of other primates which is further evidence for restrictions on a fully upright striding gait in primates that transition to bipedalism. It differs from the facultative bipedalism of other primates in the lack of an extended double-support phase and short aerial phases at higher speeds that make it a run by kinematic definition. This demonstrates that facultative bipedalism of quadrupedal primates need not necessarily be a walking gait. Copyright © 2011 Wiley-Liss, Inc.

  19. Finite-correlation-time effects in the kinematic dynamo problem

    International Nuclear Information System (INIS)

    Schekochihin, Alexander A.; Kulsrud, Russell M.

    2001-01-01

    Most of the theoretical results on the kinematic amplification of small-scale magnetic fluctuations by turbulence have been confined to the model of white-noise-like (δ-correlated in time) advecting turbulent velocity field. In this work, the statistics of the passive magnetic field in the diffusion-free regime are considered for the case when the advecting flow is finite-time correlated. A new method is developed that allows one to systematically construct the correlation-time expansion for statistical characteristics of the field such as its probability density function or the complete set of its moments. The expansion is valid provided the velocity correlation time is smaller than the characteristic growth time of the magnetic fluctuations. This expansion is carried out up to first order in the general case of a d-dimensional arbitrarily compressible advecting flow. The growth rates for all moments of the magnetic-field strength are derived. The effect of the first-order corrections due to the finite correlation time is to reduce these growth rates. It is shown that introducing a finite correlation time leads to the loss of the small-scale statistical universality, which was present in the limit of the δ-correlated velocity field. Namely, the shape of the velocity time-correlation profile and the large-scale spatial structure of the flow become important. The latter is a new effect, that implies, in particular, that the approximation of a locally-linear shear flow does not fully capture the effect of nonvanishing correlation time. Physical applications of this theory include the small-scale kinematic dynamo in the interstellar medium and protogalactic plasmas

  20. Kinematics and Workspace of a 4-DOF Hybrid Palletizing Robot

    Directory of Open Access Journals (Sweden)

    Yong Tao

    2014-06-01

    Full Text Available We presented the kinematical analysis of a 4-DOF hybrid palletizing robot. The palletizing robot structure was proposed and the arm model of the robot was presented. The kinematical analysis of the end robotic manipulator was given. As a result, the position, velocity, and acceleration curves as well as the maximum workspace were demonstrated by simulation in Matlab. This study would be useful for the kinematical characteristics of the 4-DOF palletizing robot in space.

  1. FORWARD KINEMATICS ANALYSIS OF 6-DOF ARC WELDING ROBOT

    OpenAIRE

    DR. ANURAG VERMA; MEHUL GOR

    2010-01-01

    The forward kinematics problem is concerned with the relationship between the individual joints of the robot manipulator and the position and orientation of the tool or end-effector. Stated more formally, the forward kinematics problem is to determine the position and orientation of the end-effector, given the values for the jointvariables of the robot. Present work is an attempt to develop kinematic model of a 6 DOF robot which is used for arc welding operation. Developed model will determin...

  2. Optimal kinematics and morphologies for spermatozoa

    Science.gov (United States)

    Tam, Daniel; Hosoi, A. E.

    2011-04-01

    We investigate the role of hydrodynamics in the evolution of the morphology and the selection of kinematics in simple uniflagellated microorganisms. We find that the most efficient swimming strategies are characterized by symmetrical, nonsinusoidal bending waves propagating from the base of the head to the tip of the tail. In addition, we show that the ideal tail-to-head length ratio for such a swimmer is ≈12 and that this predicted ratio is consistent with data collected from over 400 species of mammalian sperm.

  3. Galaxy structure and kinematics towards the NGP

    OpenAIRE

    Spagna, A.; Cacciari, C.; Drimmel, R.; Kinman, T.; Lattanzi, M. G.; Smart, R. L.

    2002-01-01

    We present a proper motion survey over about 200 square degrees towards the NGP, based on the material used for the construction of the GSC-II, that we are using to study the vertical structure and kinematics of the Galaxy. In particular, we measured the rotation velocity of the halo up to 10 kpc above the galactic plane traced by a sample of RR Lyr{\\ae} and BHB giants for which radial velocities were used to recover the complete distribution of the spatial velocities. Finally, the impact of ...

  4. JFKengine: A Jacobian and Forward Kinematics Generator

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, K.N.

    2003-02-13

    During robot path planning and control the equations that describe the robot motions are determined and solved. Historically these expressions were derived analytically off-line. For robots that must adapt to their environment or perform a wide range of tasks, a way is needed to rapidly re-derive these expressions to take into account the robot kinematic changes, such as when a tool is added to the end-effector. The JFKengine software was developed to automatically produce the expressions representing the manipulator arm motion, including the manipulator arm Jacobian and the forward kinematic expressions. Its programming interface can be used in conjunction with robot simulation software or with robot control software. Thus, it helps to automate the process of configuration changes for serial robot manipulators. If the manipulator undergoes a geometric change, such as tool acquisition, then JFKengine can be invoked again from the control or simulation software, passing it parameters for the new arm configuration. This report describes the automated processes that are implemented by JFKengine to derive the kinematic equations and the programming interface by which it is invoked. Then it discusses the tree data structure that was chosen to store the expressions, followed by several examples of portions of expressions as represented in the tree. The C++ classes and their methods that implement the expression differentiation and evaluation operations are described. The algorithms used to construct the Jacobian and forward kinematic equations using these basic building blocks are then illustrated. The activity described in this report is part of a larger project entitled ''Multi-Optimization Criteria-Based Robot Behavioral Adaptability and Motion Planning'' that focuses on the development of a methodology for the generalized resolution of robot motion equations with time-varying configurations, constraints, and task objective criteria. A specific

  5. Theory of gearing kinematics, geometry, and synthesis

    CERN Document Server

    Radzevich, Stephen P

    2012-01-01

    The first book of its kind, Theory of Gearing: Kinematics, Geometry, and Synthesis systematically develops a scientific theory of gearing that makes it possible to synthesize novel gears with the desired performance. Written by a leading gearing expert who holds more than 200 patents, it presents a modern methodology for gear design. The proposed theory is based on a key postulate: all the design parameters for an optimal gear pair for a particular application can be derived from (a) a given configuration of the rotation vectors of the driving and driven shafts and (b) the power transmitted by

  6. Null-strut calculus. I. Kinematics

    International Nuclear Information System (INIS)

    Kheyfets, A.; LaFave, N.J.; Miller, W.A.

    1990-01-01

    This paper describes the kinematics of null-strut calculus---a 3+1 Regge calculus approach to general relativity. We show how to model the geometry of spacetime with simplicial spacelike three-geometries (TET's) linked to ''earlier'' and ''later'' momentumlike lattice surfaces (TET * ) entirely by light rays or ''null struts.'' These three-layered lattice spacetime geometries are defined and analyzed using combinatorial formulas for the structure of polytopes. The following paper in this series describes how these three-layered spacetime lattices are used to model spacetimes in full conformity with Einstein's theory of gravity

  7. Kinematics of an infinitely flexible robot arm

    Science.gov (United States)

    Choi, P. J.; Rice, J. A.; Cesarone, J. C.

    1993-06-01

    An effort is made to define a command-and-control algorithm for a flexible robot arm design which maximizes flexibility through its large number of degrees-of-freedom, in the manner of a 'tentacle'. Algorithms including both forward and inverse kinematics are developed for commanding smooth arm motions in the presence of obstacles, on the basis of Catmull-Rom splines and local radius-of-curvature commands to discrete actuators along the length of the arm. Sample trajectories are examined, and a spline-curve algorithm is successfully applied for this arm configuration; the accuracy and collision-avoidance of the arm are verified by means of a simulation.

  8. Automobile Collisions, Kinematics and Related Injury Patterns

    Science.gov (United States)

    Siegel, A. W.

    1972-01-01

    It has been determined clinically that fatalities and injury severity resulting from automobile collisions have decreased during the last five years for low impact speeds. This reduction is a direct result of the application of biomechanics and occupant kinematics, as well as changes in automobile design. The paper defines terminology used in the field of mechanics and develops examples and illustrations of the physical concepts of acceleration, force strength, magnitude duration, rate of onset and others, as they apply to collision phenomena and injury. The mechanism of injury pattern reduction through the use of restraint systems is illustrated. PMID:5059661

  9. 38 CFR 3.810 - Clothing allowance.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Clothing allowance. 3.810..., Compensation, and Dependency and Indemnity Compensation Special Benefits § 3.810 Clothing allowance. (a) Except... therefor, to an annual clothing allowance as specified in 38 U.S.C. 1162. The annual clothing allowance is...

  10. 45 CFR 2543.27 - Allowable costs.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Allowable costs. 2543.27 Section 2543.27 Public... ORGANIZATIONS Post-Award Requirements Financial and Program Management § 2543.27 Allowable costs. For each kind of recipient, there is a set of Federal principles for determining allowable costs. Allowability of...

  11. 34 CFR 304.21 - Allowable costs.

    Science.gov (United States)

    2010-07-01

    ... 34 Education 2 2010-07-01 2010-07-01 false Allowable costs. 304.21 Section 304.21 Education... Grantee § 304.21 Allowable costs. In addition to the allowable costs established in the Education... allowable expenditures by projects funded under the program: (a) Cost of attendance, as defined in Title IV...

  12. 45 CFR 602.22 - Allowable costs.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false Allowable costs. 602.22 Section 602.22 Public... Requirements § 602.22 Allowable costs. (a) Limitation on use of funds. Grant funds may be used only for: (1) The allowable costs of the grantees, subgrantees and cost-type contractors, including allowable costs...

  13. 2 CFR 215.27 - Allowable costs.

    Science.gov (United States)

    2010-01-01

    ... 2 Grants and Agreements 1 2010-01-01 2010-01-01 false Allowable costs. 215.27 Section 215.27... § 215.27 Allowable costs. For each kind of recipient, there is a set of Federal principles for determining allowable costs. Allowability of costs shall be determined in accordance with the cost principles...

  14. 24 CFR 84.27 - Allowable costs.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Allowable costs. 84.27 Section 84....27 Allowable costs. For each kind of recipient, there is a set of Federal principles for determining allowable costs. Allowability of costs shall be determined in accordance with the cost principles applicable...

  15. 50 CFR 80.15 - Allowable costs.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Allowable costs. 80.15 Section 80.15... WILDLIFE RESTORATION AND DINGELL-JOHNSON SPORT FISH RESTORATION ACTS § 80.15 Allowable costs. (a) What are allowable costs? Allowable costs are costs that are necessary and reasonable for accomplishment of approved...

  16. 49 CFR 266.11 - Allowable costs.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Allowable costs. 266.11 Section 266.11... TRANSPORTATION ACT § 266.11 Allowable costs. Allowable costs include only the following costs which are properly allocable to the work performed: Planning and program operation costs which are allowed under Federal...

  17. 46 CFR 154.421 - Allowable stress.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Allowable stress. 154.421 Section 154.421 Shipping COAST... § 154.421 Allowable stress. The allowable stress for the integral tank structure must meet the American Bureau of Shipping's allowable stress for the vessel's hull published in “Rules for Building and Classing...

  18. 46 CFR 154.440 - Allowable stress.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Allowable stress. 154.440 Section 154.440 Shipping COAST... Tank Type A § 154.440 Allowable stress. (a) The allowable stresses for an independent tank type A must... Commandant (CG-522). (b) A greater allowable stress than required in paragraph (a)(1) of this section may be...

  19. Rigid-body kinematics versus flapping kinematics of a flapping wing micro air vehicle

    NARCIS (Netherlands)

    Caetano, J.V.; Weehuizen, M.B.; De Visser, C.C.; De Croon, G.C.H.E.; Mulder, M.

    2015-01-01

    Several formulations have been proposed to model the dynamics of ornithopters, with inconclusive results regarding the need for complex kinematic formulations. Furthermore, the impact of assumptions made in the collected results was never assessed by comparing simulations with real flight data. In

  20. Geometric deviation modeling by kinematic matrix based on Lagrangian coordinate

    Science.gov (United States)

    Liu, Weidong; Hu, Yueming; Liu, Yu; Dai, Wanyi

    2015-09-01

    Typical representation of dimension and geometric accuracy is limited to the self-representation of dimension and geometric deviation based on geometry variation thinking, yet the interactivity affection of geometric variation and gesture variation of multi-rigid body is not included. In this paper, a kinematic matrix model based on Lagrangian coordinate is introduced, with the purpose of unified model for geometric variation and gesture variation and their interactive and integrated analysis. Kinematic model with joint, local base and movable base is built. The ideal feature of functional geometry is treated as the base body; the fitting feature of functional geometry is treated as the adjacent movable body; the local base of the kinematic model is fixed onto the ideal geometry, and the movable base of the kinematic model is fixed onto the fitting geometry. Furthermore, the geometric deviation is treated as relative location or rotation variation between the movable base and the local base, and it's expressed by the Lagrangian coordinate. Moreover, kinematic matrix based on Lagrangian coordinate for different types of geometry tolerance zones is constructed, and total freedom for each kinematic model is discussed. Finally, the Lagrangian coordinate library, kinematic matrix library for geometric deviation modeling is illustrated, and an example of block and piston fits is introduced. Dimension and geometric tolerances of the shaft and hole fitting feature are constructed by kinematic matrix and Lagrangian coordinate, and the results indicate that the proposed kinematic matrix is capable and robust in dimension and geometric tolerances modeling.

  1. Kinematic and Attribute Fusion Using a Bayesian Belief Network Framework

    National Research Council Canada - National Science Library

    Krieg, Mark L

    2006-01-01

    .... However, attribute information has the potential to not only provide identity and class information, but it may also improve data association and kinematic tracking performance, Bayesian Belief...

  2. The Pleiades apex and its kinematical structure

    Science.gov (United States)

    Elsanhoury, W. H.; Postnikova, E. S.; Chupina, N. V.; Vereshchagin, S. V.; Sariya, Devesh P.; Yadav, R. K. S.; Jiang, Ing-Guey

    2018-03-01

    A study of cluster characteristics and internal kinematical structure of the middle-aged Pleiades open star cluster is presented. The individual star apexes and various cluster kinematical parameters including the velocity ellipsoid parameters are determined using both Hipparcos and Gaia data. Modern astrometric parameters were taken from the Gaia Data Release 1 (DR1) in combination with the Radial Velocity Experiment Fifth Data Release (DR5). The necessary set of parameters including parallaxes, proper motions and radial velocities are used for n=17 stars from Gaia DR1+RAVE DR5 and for n=19 stars from the Hipparcos catalog using SIMBAD data base. Single stars are used to improve accuracy by eliminating orbital movements. RAVE DR5 measurements were taken only for the stars with the radial velocity errors not exceeding 2 km/s. For the Pleiades stars taken from Gaia, we found mean heliocentric distance as 136.8 ± 6.4 pc, and the apex position is calculated as: A_{CP}=92°.52± 1°.72, D_{CP}=-42°.28± 2°.56 by the convergent point method and A0=95°.59± 2°.30 and D0=-50°.90± 2°.04 using AD-diagram method (n=17 in both cases). The results are compared with those obtained historically before the Gaia mission era.

  3. A KINEMATIC STUDY OF FINSWIMMING AT SURFACE

    Directory of Open Access Journals (Sweden)

    Pier-Giorgio Zanone

    2004-06-01

    Full Text Available Finswimming is a sport of speed practiced on the surface or underwater, in which performance is based on whole-body oscillations. The present study investigated the undulatory motion performed by finswimmers at the surface. This study aiming to analyze the influence of the interaction of gender, practice level, and race distance on selected kinematic parameters. Six elite and six novices finswimmers equipped with joints markers (wrist, elbow, shoulder, hip, knee, and ankle were recorded in the sagittal plane. The position of these anatomical marks was digitized at 50 Hz. An automated motion analysis software yielded velocity, vertical amplitude, frequency, and angular position. Results showed that stroke frequency decreased whereas the mean amplitude of all joints increased with increasing race distance (p < 0.01. Mean joint amplitude for the upper limbs (wrist, elbow and shoulder was smaller for experts than for novices. Whereas that of the ankle was larger, so that the oscillation amplitude increased from shoulder to ankle. Elite male finswimmers were pitching more acutely than female. Moreover, elite male finswimmers showed a smaller knee bending than novices and than elite females (p < 0.01. This indicated that elite male finswimmers attempt to reduce drag forces thanks to a weak knee bending and a low upper limbs pitch. To sum up, gender, expertise, and race distance affect the performance and its kinematics in terms frontal drag. Expertise in finswimming requires taking advantage of the mechanical constraints pertaining to hydrodynamic constraints in order to optimize performance

  4. Feeding kinematics of phyllomedusine tree frogs.

    Science.gov (United States)

    Gray, L A; Nishikawa, K C

    1995-02-01

    Previous studies have demonstrated that the phyllomedusine hylids possess highly protrusible tongues, a derived characteristic within the family Hylidae. In the present study, the kinematics of the feeding behavior of a phyllomedusine species, Pachymedusa dacnicolor, was analyzed using high-speed video (180 frames s-1). Its behavior was compared with that of Hyla cinerea, a species with a weakly protrusible tongue. P. dacnicolor exhibits a faster rate of tongue protraction, a longer gape cycle and more variable feeding kinematics than H. cinerea. In addition, the tongue is used in a unique 'fly-swatter' fashion, to pin the prey to the substratum as the frog completes the lunge. The rapid tongue protraction, extended gape cycle and fly-swatter action may have evolved in response to a diet of large, rapidly moving insects. In addition, several duration variables of the feeding cycle were greater for misses than for captures and drops, which suggests that sensory feedback rather than biomechanics controls gape cycle duration.

  5. A Hybrid Neural Network Approach for Kinematic Modeling of a Novel 6-UPS Parallel Human-Like Mastication Robot

    Directory of Open Access Journals (Sweden)

    Hadi Kalani

    2016-04-01

    Full Text Available Introduction we aimed to introduce a 6-universal-prismatic-spherical (UPS parallel mechanism for the human jaw motion and theoretically evaluate its kinematic problem. We proposed a strategy to provide a fast and accurate solution to the kinematic problem. The proposed strategy could accelerate the process of solution-finding for the direct kinematic problem by reducing the number of required iterations in order to reach the desired accuracy level. Materials and Methods To overcome the direct kinematic problem, an artificial neural network and third-order Newton-Raphson algorithm were combined to provide an improved hybrid method. In this method, approximate solution was presented for the direct kinematic problem by the neural network. This solution could be considered as the initial guess for the third-order Newton-Raphson algorithm to provide an answer with the desired level of accuracy. Results The results showed that the proposed combination could help find a approximate solution and reduce the execution time for the direct kinematic problem, The results showed that muscular actuations showed periodic behaviors, and the maximum length variation of temporalis muscle was larger than that of masseter and pterygoid muscles. By reducing the processing time for solving the direct kinematic problem, more time could be devoted to control calculations.. In this method, for relatively high levels of accuracy, the number of iterations and computational time decreased by 90% and 34%, respectively, compared to the conventional Newton method. Conclusion The present analysis could allow researchers to characterize and study the mastication process by specifying different chewing patterns (e.g., muscle displacements.

  6. Cooling and kinematics in the Central Molecular Zone

    Science.gov (United States)

    Ragan, Sarah

    The Central Molecular Zone (CMZ) of the Milky Way contains a huge reservoir of molecular gas, and yet its star formation efficiency appears to be significantly lower than expected from standard star formation relations. This suggests that additional physics must be considered in order to understand the regulation of star formation in the CMZ. We propose GREAT observations of the [OI] and [CII] transitions toward three compact clouds residing in the so-called 100 pc ring surrounding the Galactic Centre. These lines are predicted to be the primary coolants of molecular clouds in this harsh environment. Measuring the strength of the [CII] and [OI] line emission produced by the clouds will therefore allow us to constrain their total cooling rate, while the [OI]/[CII] line ratio and the ratio of both lines relative to the measured FIR emission will allow us to constrain the density and temperature of the clouds, and hence the intensity of the cosmic ray ionization rate in their vicinity. We can test models that predict that the CMZ is a unique environment in which oxygen dominates carbon as a coolant. The superb velocity resolution of GREAT will also allow us for the first time to study the kinematics of the warm gas in the clouds, which we expect to fill much of their volume. Finally, by comparing clouds at different locations within the 100 pc ring, we will be able to study whether the age of the clouds increases as we move away from Sgr A*, allowing us to test the idea that the formation of the clouds may have been triggered by the tidal influence of the Milky Way's central black hole and nuclear star cluster. These ground-breaking observations are only possible with SOFIA and offer several different pathways to high-impact science.

  7. Rate effects on timing, key velocity, and finger kinematics in piano performance.

    Science.gov (United States)

    Bella, Simone Dalla; Palmer, Caroline

    2011-01-01

    We examined the effect of rate on finger kinematics in goal-directed actions of pianists. In addition, we evaluated whether movement kinematics can be treated as an indicator of personal identity. Pianists' finger movements were recorded with a motion capture system while they performed melodies from memory at different rates. Pianists' peak finger heights above the keys preceding keystrokes increased as tempo increased, and were attained about one tone before keypress. These rate effects were not simply due to a strategy to increase key velocity (associated with tone intensity) of the corresponding keystroke. Greater finger heights may compensate via greater tactile feedback for a speed-accuracy tradeoff that underlies the tendency toward larger temporal variability at faster tempi. This would allow pianists to maintain high temporal accuracy when playing at fast rates. In addition, finger velocity and accelerations as pianists' fingers approached keys were sufficiently unique to allow pianists' identification with a neural-network classifier. Classification success was higher in pianists with more extensive musical training. Pianists' movement "signatures" may reflect unique goal-directed movement kinematic patterns, leading to individualistic sound.

  8. Rate effects on timing, key velocity, and finger kinematics in piano performance.

    Directory of Open Access Journals (Sweden)

    Simone Dalla Bella

    Full Text Available We examined the effect of rate on finger kinematics in goal-directed actions of pianists. In addition, we evaluated whether movement kinematics can be treated as an indicator of personal identity. Pianists' finger movements were recorded with a motion capture system while they performed melodies from memory at different rates. Pianists' peak finger heights above the keys preceding keystrokes increased as tempo increased, and were attained about one tone before keypress. These rate effects were not simply due to a strategy to increase key velocity (associated with tone intensity of the corresponding keystroke. Greater finger heights may compensate via greater tactile feedback for a speed-accuracy tradeoff that underlies the tendency toward larger temporal variability at faster tempi. This would allow pianists to maintain high temporal accuracy when playing at fast rates. In addition, finger velocity and accelerations as pianists' fingers approached keys were sufficiently unique to allow pianists' identification with a neural-network classifier. Classification success was higher in pianists with more extensive musical training. Pianists' movement "signatures" may reflect unique goal-directed movement kinematic patterns, leading to individualistic sound.

  9. Rate Effects on Timing, Key Velocity, and Finger Kinematics in Piano Performance

    Science.gov (United States)

    Dalla Bella, Simone; Palmer, Caroline

    2011-01-01

    We examined the effect of rate on finger kinematics in goal-directed actions of pianists. In addition, we evaluated whether movement kinematics can be treated as an indicator of personal identity. Pianists' finger movements were recorded with a motion capture system while they performed melodies from memory at different rates. Pianists' peak finger heights above the keys preceding keystrokes increased as tempo increased, and were attained about one tone before keypress. These rate effects were not simply due to a strategy to increase key velocity (associated with tone intensity) of the corresponding keystroke. Greater finger heights may compensate via greater tactile feedback for a speed-accuracy tradeoff that underlies the tendency toward larger temporal variability at faster tempi. This would allow pianists to maintain high temporal accuracy when playing at fast rates. In addition, finger velocity and accelerations as pianists' fingers approached keys were sufficiently unique to allow pianists' identification with a neural-network classifier. Classification success was higher in pianists with more extensive musical training. Pianists' movement “signatures” may reflect unique goal-directed movement kinematic patterns, leading to individualistic sound. PMID:21731615

  10. Allowance Holdings and Transfers Data Inventory

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Allowance Holdings and Transfers Data Inventory contains measured data on holdings and transactions of allowances under the NOx Budget Trading Program (NBP), a...

  11. Clean Air Markets - Allowances Query Wizard

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Allowances Query Wizard is part of a suite of Clean Air Markets-related tools that are accessible at http://camddataandmaps.epa.gov/gdm/index.cfm. The Allowances...

  12. Constraint Study for a Hand Exoskeleton: Human Hand Kinematics and Dynamics

    Directory of Open Access Journals (Sweden)

    Fai Chen Chen

    2013-01-01

    Full Text Available In the last few years, the number of projects studying the human hand from the robotic point of view has increased rapidly, due to the growing interest in academic and industrial applications. Nevertheless, the complexity of the human hand given its large number of degrees of freedom (DoF within a significantly reduced space requires an exhaustive analysis, before proposing any applications. The aim of this paper is to provide a complete summary of the kinematic and dynamic characteristics of the human hand as a preliminary step towards the development of hand devices such as prosthetic/robotic hands and exoskeletons imitating the human hand shape and functionality. A collection of data and constraints relevant to hand movements is presented, and the direct and inverse kinematics are solved for all the fingers as well as the dynamics; anthropometric data and dynamics equations allow performing simulations to understand the behavior of the finger.

  13. Kinematic and dynamic modeling and approximate analysis of a roller chain drive

    DEFF Research Database (Denmark)

    Fuglede, Niels; Thomsen, Jon Juel

    2016-01-01

    for analytical studies of the coupled motion of the chain spans and driven sprocket. Parametric excitation of the spans come from sprocket angular displacements, and the driven sprocket acts as a boundary which can be compliant in the axial direction. External transverse excitation of the spans comes from...... and coupled motion. Together, the kinematic and dynamic model are aimed toward providing a framework for conducting and understanding both numerical, and experimental investigations of roller chain drive dynamics.......A simple roller chain drive consisting of two sprockets connected by tight chain spans is investigated. First, a kinematic model is presented which include both spans and sprockets. An approach for calculating the chain wrapping length is presented, which also allows for the exact calculation...

  14. 20 CFR 632.258 - Allowable activities.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Allowable activities. 632.258 Section 632.258... EMPLOYMENT AND TRAINING PROGRAMS Summer Youth Employment and Training Programs § 632.258 Allowable activities. Allowable activities are those listed in § 632.78-80 except that community service employment is not...

  15. 42 CFR 417.802 - Allowable costs.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Allowable costs. 417.802 Section 417.802 Public... PLANS Health Care Prepayment Plans § 417.802 Allowable costs. (a) General rule. The costs that are considered allowable for HCPP reimbursement are the same as those for reasonable cost HMOs and CMPs specified...

  16. 45 CFR 1180.56 - Allowable costs.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 3 2010-10-01 2010-10-01 false Allowable costs. 1180.56 Section 1180.56 Public... by a Grantee General Administrative Responsibilities § 1180.56 Allowable costs. (a) Determination of costs allowable under a grant is made in accordance with government-wide cost principles in applicable...

  17. 45 CFR 2541.220 - Allowable costs.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 4 2010-10-01 2010-10-01 false Allowable costs. 2541.220 Section 2541.220 Public... Post-Award Requirements § 2541.220 Allowable costs. (a) Limitation on use of funds. Grant funds may be used only for— (1) The allowable costs of the grantees, subgrantees and cost-type contractors...

  18. 50 CFR 85.41 - Allowable costs.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Allowable costs. 85.41 Section 85.41... Use/Acceptance of Funds § 85.41 Allowable costs. (a) Allowable grant costs are limited to those costs... applicable Federal cost principles in 43 CFR 12.60(b). Purchase of informational signs, program signs, and...

  19. 43 CFR 12.927 - Allowable costs.

    Science.gov (United States)

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Allowable costs. 12.927 Section 12.927... COST PRINCIPLES FOR ASSISTANCE PROGRAMS Uniform Administrative Requirements for Grants and Agreements... Requirements § 12.927 Allowable costs. Federal awarding agencies shall determine allowable costs in accordance...

  20. 46 CFR 154.428 - Allowable stress.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Allowable stress. 154.428 Section 154.428 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR... § 154.428 Allowable stress. The membrane tank and the supporting insulation must have allowable stresses...

  1. 46 CFR 154.447 - Allowable stress.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Allowable stress. 154.447 Section 154.447 Shipping COAST... Tank Type B § 154.447 Allowable stress. (a) An independent tank type B designed from bodies of revolution must have allowable stresses 3 determined by the following formulae: 3 See Appendix B for stress...

  2. 34 CFR 642.40 - Allowable costs.

    Science.gov (United States)

    2010-07-01

    ... 34 Education 3 2010-07-01 2010-07-01 false Allowable costs. 642.40 Section 642.40 Education...? § 642.40 Allowable costs. Allowable project costs may include the following costs reasonably related to carrying out a Training Program project: (a) Rental of space, if space is not available at a sponsoring...

  3. 34 CFR 675.33 - Allowable costs.

    Science.gov (United States)

    2010-07-01

    ... costs. (a)(1) Allowable and unallowable costs. Except as provided in paragraph (a)(2) of this section, costs reasonably related to carrying out the programs described in § 675.32 are allowable. (2) Costs... 34 Education 3 2010-07-01 2010-07-01 false Allowable costs. 675.33 Section 675.33 Education...

  4. Force generation of bio-inspired hover kinematics

    NARCIS (Netherlands)

    Vandenheede, R.B.R.; Bernal, L.P.; Morrison, C.L.; Humbert, S.

    2012-01-01

    This paper presents the results of an experimental study of the aerodynamics of an elliptical flap plate wing in pitch-plunge motion. Several wing motion kinematics are derived from the kinematics of the Agrius Convolvuli (hawk moth) in hover. The experiments are conducted at a Reynolds number of 4,

  5. Testing Mass Determinations of Supermassive Black Holes via Stellar Kinematics

    NARCIS (Netherlands)

    Cappellari, Michele; M. McDermid, Richard; Bacon, R.; L. Davies, Roger; T. de Zeeuw, P.; Emsellem, Eric; Falcón-Barroso, Jesús; Krajnović, Davor; Kuntschner, Harald; Peletier, R.F.; Sarzi, Marc; C. E. van den Bosch, Remco; van de Ven, Glenn; Debattista, Victor P.; Popescu, Cristina C.

    We investigate the accuracy of mass determinations MBH of supermassive black holes in galaxies using dynamical models of the stellar kinematics. We compare 10 of our MBH measurements, using integral-field OASIS kinematics, to published values. For a sample of 25 galaxies we confront our new MBH

  6. Kinematic and Dynamic Analysis of a Lower Limb Exoskeleton

    OpenAIRE

    Tawakal Hasnain Baluch; Adnan Masood; Javaid Iqbal; Umer Izhar; Umar Shahbaz Khan

    2012-01-01

    This paper will provide the kinematic and dynamic analysis of a lower limb exoskeleton. The forward and inverse kinematics of proposed exoskeleton is performed using Denevit and Hartenberg method. The torques required for the actuators will be calculated using Lagrangian formulation technique. This research can be used to design the control of the proposed exoskeleton.

  7. Kinematics of large scale asymmetric folds and associated smaller ...

    Indian Academy of Sciences (India)

    active-hinge folding (involving lateral migration of active axial surfaces, e.g., Suppe 1983) are invoked to explain finite fold development. Any inference about fold kinematics is based on the analysis of distributions of diagnostic deformation features (Stewart and Alvarez 1991; Fischer et al. Keywords. Kinematic history ...

  8. Kinematic Mapping in Semi-Euclidean 4-Space

    Directory of Open Access Journals (Sweden)

    Mehdi JAFARI

    2014-10-01

    Full Text Available We study the some algebraic properties of matrix associated to Hamilton operators is defined for semi-quaternions. The kinematic mapping corresponding to these operators in semi-Euclidean 4-space is same as the kinematic mapping of Blaschke and Grünwald.Keywords: Hamilton operators, Quasi-elliptic geometry, Semi-quaternion

  9. Lingual Kinematics during Rapid Syllable Repetition in Parkinson's Disease

    Science.gov (United States)

    Wong, Min Ney; Murdoch, Bruce E.; Whelan, Brooke-Mai

    2012-01-01

    Background: Rapid syllable repetition tasks are commonly used in the assessment of motor speech disorders. However, little is known about the articulatory kinematics during rapid syllable repetition in individuals with Parkinson's disease (PD). Aims: To investigate and compare lingual kinematics during rapid syllable repetition in dysarthric…

  10. Shaping of Reach-to-Grasp Kinematics by Intentions

    DEFF Research Database (Denmark)

    Egmose, Ida; Køppe, Simo

    2017-01-01

    When we reach to grasp something, we need to take into account both the properties of the object we are grasping and the intention we have in mind. Previous research has found these constraints to be visible in the reach-to-grasp kinematics, but there is no consensus on which kinematic parameters...

  11. Kinematic analysis of competitive sprinting | Ansari | African Journal ...

    African Journals Online (AJOL)

    The results of the study showed that the kinematic variables i.e. knee angle, hip angle, ankle angle, shoulder rotation and extension had a significant influence on sprinting style. The results indicated that the kinematic variables of running style, knee angle at landing, hip flexion, ankle angle at landing, ankle angle at take-off, ...

  12. Predicting Object Size from Hand Kinematics : A Temporal Perspective

    NARCIS (Netherlands)

    Ansuini, C.; Cavallo, A.; Koul, A.; Jacono, M.; Yang, Y.; Becchio, C.

    2015-01-01

    Research on reach-to-grasp movements generally concentrates on kinematics values that are expression of maxima, in particular the maximum aperture of the hand and the peak of wrist velocity. These parameters provide a snapshot description of movement kinematics at a specific time point during reach,

  13. Monitoring diver kinematics with dielectric elastomer sensors

    Science.gov (United States)

    Walker, Christopher R.; Anderson, Iain A.

    2017-04-01

    Diving, initially motivated for food purposes, is crucial to the oil and gas industry, search and rescue, and is even done recreationally by millions of people. There is a growing need however, to monitor the health and activity of divers. The Divers Alert Network has reported on average 90 fatalities per year since 1980. Furthermore an estimated 1000 divers require recompression treatment for dive-related injuries every year. One means of monitoring diver activity is to integrate strain sensors into a wetsuit. This would provide kinematic information on the diver potentially improving buoyancy control assessment, providing a platform for gesture communication, detecting panic attacks and monitoring diver fatigue. To explore diver kinematic monitoring we have coupled dielectric elastomer sensors to a wetsuit worn by the pilot of a human-powered wet submarine. This provided a unique platform to test the performance and accuracy of dielectric elastomer strain sensors in an underwater application. The aim of this study was to assess the ability of strain sensors to monitor the kinematics of a diver. This study was in collaboration with the University of Auckland's human-powered submarine team, Team Taniwha. The pilot, completely encapsulated in a hull, pedals to propel the submarine forward. Therefore this study focused on leg motion as that is the primary motion of the submarine pilot. Four carbon-filled silicone dielectric elastomer sensors were fabricated and coupled to the pilot's wetsuit. The first two sensors were attached over the knee joints, with the remaining two attached between the pelvis and thigh. The goal was to accurately measure leg joint angles thereby determining the position of each leg relative to the hip. A floating data acquisition unit monitored the sensors and transmitted data packets to a nearby computer for real-time processing. A GoPro Hero 4 silver edition was used to capture the experiments and provide a means of post-validation. The

  14. Opportunities for measuring wheelchair kinematics in match settings; reliability of a three inertial sensor configuration

    NARCIS (Netherlands)

    van der Slikke, R.M.A.; Berger, M.A.; Bregman, D.J.J.; Lagerberg, A.H.; Veeger, H.E.J.

    2015-01-01

    Knowledge of wheelchair kinematics during a match is prerequisite for performance improvement in wheelchair basketball. Unfortunately, no measurement system providing key kinematic outcomes proved to be reliable in competition. In this study, the reliability of estimated wheelchair kinematics based

  15. 21st Century Kinematics : The 2012 NSF Workshop

    CERN Document Server

    2013-01-01

    21st Century Kinematics focuses on algebraic problems in the analysis and synthesis of mechanisms and robots, compliant mechanisms, cable-driven systems and protein kinematics. The specialist contributors provide the background for a series of presentations at the 2012 NSF Workshop. The text shows how the analysis and design of innovative mechanical systems yield increasingly complex systems of polynomials, characteristic of those systems. In doing so, takes advantage of increasingly sophisticated computational tools developed for numerical algebraic geometry and demonstrates the now routine derivation of polynomial systems dwarfing the landmark problems of even the recent past. The 21st Century Kinematics workshop echoes the NSF-supported 1963 Yale Mechanisms Teachers Conference that taught a generation of university educators the fundamental principles of kinematic theory. As such these proceedings will be provide admirable supporting theory for a graduate course in modern kinematics and should be of consid...

  16. Plastic frames: Reduction of the kinematical inequality and optimization

    International Nuclear Information System (INIS)

    Brousse, P.

    1979-01-01

    It is well-known that the following inequality plays an essential part in the theory of perfectly plastic frames: for all kinematically admissible mechanisms and for bending moments associated with the hinge rotations by the flow rule, the plastic dissipation power is greater than or equal to the load power. This inequality will be termed as the kinematic inequality. It contains parameters generating the mechanisms. In simple cases, several ingenious authors obtained appreciable results excluding parameters. But, in more complicated cases, for instance when the given quantities are not numerical, the parameters remain in the kinematic inequality, thereby precluding exploitation of the kinematic approach. In the present work we overcome this dificulty: we reduce the kinematic inequality, i.e., we replace it by inequalities containing no variable parameter; we then state a process giving automatically such inequalities; finally, we treat a practical application. (orig.)

  17. Numerical analysis of kinematic soil—pile interaction

    Science.gov (United States)

    Castelli, Francesco; Maugeri, Michele; Mylonakis, George

    2008-07-01

    In the present study, the response of singles pile to kinematic seismic loading is investigated using the computer program SAP2000@. The objectives of the study are: (1) to develop a numerical model that can realistically simulate kinematic soil-structure interaction for piles accounting for discontinuity conditions at the pile-soil interface, energy dissipation and wave propagation; (2) to use the model for evaluating kinematic interaction effects on pile response as function of input ground motion; and (3) to present a case study in which theoretical predictions are compared with results obtained from other formulations. To evaluate the effects of kinematic loading, the responses of both the free-field soil (with no piles) and the pile were compared. Time history and static pushover analyses were conducted to estimate the displacement and kinematic pile bending under seismic loadings.

  18. 2nd Conference on Interdisciplinary Applications in Kinematics

    CERN Document Server

    Flores, Francisco

    2015-01-01

    This book collects a number of important contributions presented during the Second Conference on Interdisciplinary Applications of Kinematics (IAK 2013) held in Lima, Peru. The conference brought together scientists from several research fields, such as computational kinematics, multibody systems, industrial machines, robotics, biomechanics, mechatronics, computational chemistry, and vibration analysis, and embraced all key aspects of kinematics, namely, theoretical methods, modeling, optimization, experimental validation, industrial applications, and design. Kinematics is an exciting area of computational mechanics and plays  a central role in a great variety of fields and industrial applications nowadays. Apart from research in pure kinematics, the field deals with problems of practical relevance that need to be solved in an interdisciplinary manner in order for new technologies to develop. The results presented in this book should be of interest for practicing and research engineers as well as Ph.D. stud...

  19. Forward and inverse kinematics of double universal joint robot wrists

    Science.gov (United States)

    Williams, Robert L., II

    1991-01-01

    A robot wrist consisting of two universal joints can eliminate the wrist singularity problem found on many individual robots. Forward and inverse position and velocity kinematics are presented for such a wrist having three degrees of freedom. Denavit-Hartenberg parameters are derived to find the transforms required for the kinematic equations. The Omni-Wrist, a commercial double universal joint robot wrist, is studied in detail. There are four levels of kinematic parameters identified for this wrist; three forward and three inverse maps are presented for both position and velocity. These equations relate the hand coordinate frame to the wrist base frame. They are sufficient for control of the wrist standing alone. When the wrist is attached to a manipulator arm; the offset between the two universal joints complicates the solution of the overall kinematics problem. All wrist coordinate frame origins are not coincident, which prevents decoupling of position and orientation for manipulator inverse kinematics.

  20. Freeing the Serial Mechanism Designer from Inverse Kinematic Solvability Constraints

    Directory of Open Access Journals (Sweden)

    Diana C. W. Friedman

    2010-01-01

    Full Text Available This paper presents a fast numerical solution for the inverse kinematics of a serial manipulator. The method is implemented on the C-arm, a manipulator designed for use in robotic surgery. The inverse kinematics solution provides all possible solutions for any six degree-of-freedom serial manipulator, assuming that the forward kinematics are known and that it is possible to solve for the remaining joint angles if one joint angle’s value is known. With a fast numerical method and the current levels of computing power, designing a manipulator with closed-form inverse kinematics is no longer necessary. When designing the C-arm, we therefore chose to weigh other factors, such as actuator size and patient safety, more heavily than the ability to find a closed-form inverse kinematics solution.

  1. Adjustable link for kinematic mounting systems

    Science.gov (United States)

    Hale, L.C.

    1997-07-01

    An adjustable link for kinematic mounting systems is disclosed. The adjustable link is a low-cost, passive device that provides backlash-free adjustment along its single constraint direction and flexural freedom in all other directions. The adjustable link comprises two spheres, two sockets in which the spheres are adjustable retain, and a connection link threadly connected at each end to the spheres, to provide a single direction of restraint and to adjust the length or distance between the sockets. Six such adjustable links provide for six degrees of freedom for mounting an instrument on a support. The adjustable link has applications in any machine or instrument requiring precision adjustment in six degrees of freedom, isolation from deformations of the supporting platform, and/or additional structural damping. The damping is accomplished by using a hollow connection link that contains an inner rod and a viscoelastic separation layer between the two. 3 figs.

  2. Differential Kinematics Of Contemporary Industrial Robots

    Science.gov (United States)

    Szkodny, T.

    2014-08-01

    The paper presents a simple method of avoiding singular configurations of contemporary industrial robot manipulators of such renowned companies as ABB, Fanuc, Mitsubishi, Adept, Kawasaki, COMAU and KUKA. To determine the singular configurations of these manipulators a global form of description of the end-effector kinematics was prepared, relative to the other links. On the basis of this description , the formula for the Jacobian was defined in the end-effector coordinates. Next, a closed form of the determinant of the Jacobian was derived. From the formula, singular configurations, where the determinant's value equals zero, were determined. Additionally, geometric interpretations of these configurations were given and they were illustrated. For the exemplary manipulator, small corrections of joint variables preventing the reduction of the Jacobian order were suggested. An analysis of positional errors, caused by these corrections, was presented

  3. Color-kinematic duality for form factors

    International Nuclear Information System (INIS)

    Boels, Rutger H.; Kniehl, Bernd A.; Tarasov, Oleg V.; Yang, Gang

    2012-12-01

    Recently a powerful duality between color and kinematics has been proposed for integrands of scattering amplitudes in quite general gauge theories. In this paper the duality proposal is extended to the more general class of gauge theory observables formed by form factors. After a discussion of the general setup the existence of the duality is verified in two and three loop examples in four dimensional maximally supersymmetric Yang-Mills theory which involve the stress energy tensor multiplet. In these cases the duality reproduces known results in a particularly transparent and uniform way. As a non-trivial application we obtain a very simple form of the integrand of the four-loop two-point (Sudakov) form factor which passes a large set of unitarity cut checks.

  4. Kinematic tests of exotic flat cosmological models

    International Nuclear Information System (INIS)

    Charlton, J.C.; Turner, M.S.; NASA/Fermilab Astrophysics Center, Batavia, IL)

    1987-01-01

    Theoretical prejudice and inflationary models of the very early universe strongly favor the flat, Einstein-de Sitter model of the universe. At present the observational data conflict with this prejudice. This conflict can be resolved by considering flat models of the universe which posses a smooth component of energy density. The kinematics of such models, where the smooth component is relativistic particles, a cosmological term, a network of light strings, or fast-moving, light strings is studied in detail. The observational tests which can be used to discriminate between these models are also discussed. These tests include the magnitude-redshift, lookback time-redshift, angular size-redshift, and comoving volume-redshift diagrams and the growth of density fluctuations. 58 references

  5. Color-kinematic duality for form factors

    Energy Technology Data Exchange (ETDEWEB)

    Boels, Rutger H.; Kniehl, Bernd A.; Tarasov, Oleg V.; Yang, Gang [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik

    2012-12-15

    Recently a powerful duality between color and kinematics has been proposed for integrands of scattering amplitudes in quite general gauge theories. In this paper the duality proposal is extended to the more general class of gauge theory observables formed by form factors. After a discussion of the general setup the existence of the duality is verified in two and three loop examples in four dimensional maximally supersymmetric Yang-Mills theory which involve the stress energy tensor multiplet. In these cases the duality reproduces known results in a particularly transparent and uniform way. As a non-trivial application we obtain a very simple form of the integrand of the four-loop two-point (Sudakov) form factor which passes a large set of unitarity cut checks.

  6. Kinematic tests of exotic flat cosmological models

    International Nuclear Information System (INIS)

    Charlton, J.C.; Turner, M.S.

    1986-05-01

    Theoretical prejudice and inflationary models of the very early Universe strongly favor the flat, Einstein-deSitter model of the Universe. At present the observational data conflict with this prejudice. This conflict can be resolved by considering flat models of the Universe which possess a smooth component by energy density. We study in detail the kinematics of such models, where the smooth component is relativistic particles, a cosmological term, a network of light strings, or fast-moving, light strings. We also discuss the observational tests which can be used to discriminate between these models. These tests include the magnitude-redshift, lookback time-redshift, angular size-redshift, and comoving volume-redshift diagrams and the growth of density fluctuations

  7. Robot Calibration Using Iteration and Differential Kinematics

    Science.gov (United States)

    Ye, S. H.; Wang, Y.; Ren, Y. J.; Li, D. K.

    2006-10-01

    In the applications of seam laser tracking welding robot and general measuring robot station based on stereo vision, the robot calibration is the most difficult step during the whole system calibration progress. Many calibration methods were put forward, but the exact location of base frame has to be known no matter which method was employed. However, the accurate base frame location is hard to be known. In order to obtain the position of base coordinate, this paper presents a novel iterative algorithm which can also get parameters' deviations at the same time. It was a method of employing differential kinematics to solve link parameters' deviations and approaching real values step-by-step. In the end, experiment validation was provided.

  8. KINEMATICS OF M51-TYPE INTERACTING GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Günthardt, G. I.; Agüero, M. P. [Observatorio Astronómico, Universidad Nacional de Córdoba, Laprida 854, 5000 Córdoba (Argentina); Díaz, R. J., E-mail: guillermo.gunthardt@unc.edu.ar, E-mail: mpaguero@oac.uncor.edu, E-mail: rdiaz@gemini.edu [Gemini Observatory, AURA (United States)

    2016-11-01

    We present a kinematic catalog for 21 M51-type galaxies. It consists of radial velocity distributions observed with long-slit spectroscopy along different position angles, for both the main and satellite components. We detect deviations from circular motion in most of the main galaxies of each pair, due to the gravitational perturbation produced by the satellite galaxy. However, some systems do not show significant distortions in their radial velocity curves. We found some differences between the directions of the photometric and kinematic major axes in the main galaxies with a bar subsystem. The Tully–Fisher relation in the B -band and Ks -band for the present sample of M51-type systems is flatter than in isolated galaxies. Using the radial velocity data set, we built a synthetic normalized radial velocity distribution, as a reference for future modeling of these peculiar systems. The synthetic rotation curve, representing the typical rotation curve of the main galaxy in an M51-type pair, is near to solid body-like inside 4 kpc, and then is nearly flat within the radial range 5–15 kpc. The relative position angles between the major axis of the main galaxy and the companion’s location, as well as the amplitude of the velocity difference, indicate that the orbital motion of the satellite has a large projection on the equatorial plane of the main galaxy. In addition, the differences in radial velocity between the two galaxies indicate that the satellite’s orbital motion is within the range of amplitudes of the rotation curve of the main galaxy, and all the M51-type systems studied here, except for one, are gravitationally bound.

  9. Neural learning of robot inverse kinematics transformations

    Science.gov (United States)

    Gupta, M. M.

    1994-06-01

    The accuracy of a robot arm is determined by its ability to move in a given particular task space to specific Cartesian positions that are not necessarily pretaught. As a consequence, the inverse kinematics is an important problem as it must be solved in real-time in order to position the end-effector at an appropriate Cartesian location. However, it is a difficult and challenging problem for it involves the determination whether or not at least one mathematical set of robot joint angle values exists that will produce a desired coordinate configuration. The mathematical solutions should be checked against the physical constraints associated with the manipulator. Many times, a solution many not be physically realizable in a constrained environment. The advent of artificial neural networks has made it possible to obtain general learning schemes which can be used to arrive at feasible solutions to inverse kinematics problem in a constrained environment independent of a robotic structure. In this paper, we present such a learning scheme using a dynamic neural processor (DNP). This neural model functionally mimics the subpopulation of biological neurons. For analytical simplicity, only two subpopulations of neurons, namely excitatory and inhibitory, are assumed to coexist. The DNP is a neural network structure consisting of two dynamic neural units coupled as excitatory and inhibitory neurons. It is demonstrated in this study that the DNP would avoid time consuming numerical calculations and provide, more or less, instant recall of the learned associations. The learning and adaptive nature of this neural approach is demonstrated for two- and three-linked robots.

  10. Synthetic tsunami waveform catalogs with kinematic constraints

    Directory of Open Access Journals (Sweden)

    M. A. Baptista

    2017-07-01

    Full Text Available In this study we present a comprehensive methodology to produce a synthetic tsunami waveform catalogue in the northeast Atlantic, east of the Azores islands. The method uses a synthetic earthquake catalogue compatible with plate kinematic constraints of the area. We use it to assess the tsunami hazard from the transcurrent boundary located between Iberia and the Azores, whose western part is known as the Gloria Fault. This study focuses only on earthquake-generated tsunamis. Moreover, we assume that the time and space distribution of the seismic events is known. To do this, we compute a synthetic earthquake catalogue including all fault parameters needed to characterize the seafloor deformation covering the time span of 20 000 years, which we consider long enough to ensure the representability of earthquake generation on this segment of the plate boundary. The computed time and space rupture distributions are made compatible with global kinematic plate models. We use the tsunami empirical Green's functions to efficiently compute the synthetic tsunami waveforms for the dataset of coastal locations, thus providing the basis for tsunami impact characterization. We present the results in the form of offshore wave heights for all coastal points in the dataset. Our results focus on the northeast Atlantic basin, showing that earthquake-induced tsunamis in the transcurrent segment of the Azores–Gibraltar plate boundary pose a minor threat to coastal areas north of Portugal and beyond the Strait of Gibraltar. However, in Morocco, the Azores, and the Madeira islands, we can expect wave heights between 0.6 and 0.8 m, leading to precautionary evacuation of coastal areas. The advantages of the method are its easy application to other regions and the low computation effort needed.

  11. Assessment of representational competence in kinematics

    Science.gov (United States)

    Klein, P.; Müller, A.; Kuhn, J.

    2017-06-01

    A two-tier instrument for representational competence in the field of kinematics (KiRC) is presented, designed for a standard (1st year) calculus-based introductory mechanics course. It comprises 11 multiple choice (MC) and 7 multiple true-false (MTF) questions involving multiple representational formats, such as graphs, pictures, and formal (mathematical) expressions (1st tier). Furthermore, students express their answer confidence for selected items, providing additional information (2nd tier). Measurement characteristics of KiRC were assessed in a validation sample (pre- and post-test, N =83 and N =46 , respectively), including usefulness for measuring learning gain. Validity is checked by interviews and by benchmarking KiRC against related measures. Values for item difficulty, discrimination, and consistency are in the desired ranges; in particular, a good reliability was obtained (KR 20 =0.86 ). Confidence intervals were computed and a replication study yielded values within the latter. For practical and research purposes, KiRC as a diagnostic tool goes beyond related extant instruments both for the representational formats (e.g., mathematical expressions) and for the scope of content covered (e.g., choice of coordinate systems). Together with the satisfactory psychometric properties it appears a versatile and reliable tool for assessing students' representational competency in kinematics (and of its potential change). Confidence judgments add further information to the diagnostic potential of the test, in particular for representational misconceptions. Moreover, we present an analytic result for the question—arising from guessing correction or educational considerations—of how the total effect size (Cohen's d ) varies upon combination of two test components with known individual effect sizes, and then discuss the results in the case of KiRC (MC and MTF combination). The introduced method of test combination analysis can be applied to any test comprising

  12. Kinematics of Hα Emitting Stars in Andromeda

    Science.gov (United States)

    Ilango, Megha; Ilango, Anita; Damon, Gabriel; Prichard, Laura; Guhathakurta, Puragra; PHAT Collaboration; SPLASH Collaboration

    2017-01-01

    Studying emission line stars helps improve our understanding of stellar evolution, types of stars, and their environments. In this study, we analyzed stars exhibiting Hα emission (Hα stars) in the Andromeda Galaxy. We used a combination of spectroscopic and photometric diagnostic methods to remove a population of foreground Milky Way (MW) star contaminants from our data set. The Hα stars were selected from a sample of 5295 spectra from the Spectroscopic and Photometric Landscape of Andromeda’s Stellar Halo (SPLASH) survey and accompanying photometric data from the Panchromatic Hubble Andromeda Treasury (PHAT) survey. Velocities of two classes of Hα stars, main sequence (MS) stars and asymptotic giant branch (AGB) stars, were analyzed through a novel Age-Velocity Difference Correlation (AVDC) method, which utilizes line-of-sight velocity differences (LOSVDs) in order to estimate the age of a rare stellar population. Histograms, weighted means, and weighted standard deviations of the LOSVDs were used to conclude that MS stars are more kinematically coherent than AGB stars, and that Hα stars are kinematically comparable and thus close in age to their non-Hα counterparts. With these results, it can definitively be inferred that mass loss is important in two stages of stellar evolution: massive MS and intermediate mass AGB. We hypothesized that this mass loss could either occur as a normal part of MS and AGB evolution, or that it could be emitted by only a subpopulation of MS and AGB stars throughout their life cycle. Our use of the novel AVDC method sets a precedent for the use of similar methods in predicting the ages of rare stellar subgroups.This research was supported by NASA and the National Science Foundation. Most of this work was carried out by high school students working under the auspices of the Science Internship Program at UC Santa Cruz.

  13. Synthetic tsunami waveform catalogs with kinematic constraints

    Science.gov (United States)

    Baptista, Maria Ana; Miranda, Jorge Miguel; Matias, Luis; Omira, Rachid

    2017-07-01

    In this study we present a comprehensive methodology to produce a synthetic tsunami waveform catalogue in the northeast Atlantic, east of the Azores islands. The method uses a synthetic earthquake catalogue compatible with plate kinematic constraints of the area. We use it to assess the tsunami hazard from the transcurrent boundary located between Iberia and the Azores, whose western part is known as the Gloria Fault. This study focuses only on earthquake-generated tsunamis. Moreover, we assume that the time and space distribution of the seismic events is known. To do this, we compute a synthetic earthquake catalogue including all fault parameters needed to characterize the seafloor deformation covering the time span of 20 000 years, which we consider long enough to ensure the representability of earthquake generation on this segment of the plate boundary. The computed time and space rupture distributions are made compatible with global kinematic plate models. We use the tsunami empirical Green's functions to efficiently compute the synthetic tsunami waveforms for the dataset of coastal locations, thus providing the basis for tsunami impact characterization. We present the results in the form of offshore wave heights for all coastal points in the dataset. Our results focus on the northeast Atlantic basin, showing that earthquake-induced tsunamis in the transcurrent segment of the Azores-Gibraltar plate boundary pose a minor threat to coastal areas north of Portugal and beyond the Strait of Gibraltar. However, in Morocco, the Azores, and the Madeira islands, we can expect wave heights between 0.6 and 0.8 m, leading to precautionary evacuation of coastal areas. The advantages of the method are its easy application to other regions and the low computation effort needed.

  14. Distances, Kinematics, And Structure Of The Orion Complex

    Science.gov (United States)

    Kounkel, Marina; Hartmann, Lee

    2018-01-01

    I present an analysis of the structure and kinematics of the Orion Molecular Cloud Complex in an effort to better characterize the dynamical state of the closest region of ongoing massive star formation. I measured stellar parallax and proper motions with Orion Complex. This includes the first direct distance measurements for sources that are located outside of the Orion Nebula. I identified a number of binary systems in the VLBI dataset and fitted their orbital motion, which allows for the direct measurement of the masses of the individual components. Additionally, I have identified several stars that have been ejected from the Orion Nebula due to strong gravitational interactions with the most massive members. I complemented the parallax and proper motion measurements with the observations of optical radial velocities of the stars toward the Orion Complex, probing the histories of both dynamic evolution and star formation in the region, providing a 6-dimensional model of the Complex. These observations can serve as a baseline for comparison of the upcoming results from the Gaia space telescope

  15. Reprint of 'Development, maturation and learning influence on handwriting kinematics'.

    Science.gov (United States)

    Accardo, Agostino P; Genna, Mariangela; Borean, Michela

    2013-10-01

    Handwriting is the result of a process in which linguistic, psychomotor and biomechanical factors interact with physical maturation, cognitive development and learning. Digital tablets, which record the writing in real time, allow a kinematic analysis of written trace: the implemented algorithms analyze parameters as length, duration and speed of the components (trace between two pen-lifts) and strokes (trace between two minima of curvilinear velocity). The purpose of this work is to fill, at least for Italy, the lack of normative data on typical handwriting processes. This cross-sectional study will present data on 218 right-handed and Italian mother-tongue students, attending classes from 2nd to 8th grade. They performed specific tasks (tests of writing speed; transcription of a sentence accurately vs. speedily) by a digital tablet. The analysis showed many changes of the considered parameters across the classes, as in the horizontal, curvilinear mean and peak velocities of components and strokes, with higher values in the last years of schooling and a parallel decrease in the number of strokes/letter (improvement of automation). In conclusion, some of these parameters are useful for studying development and learning of writing and their values can be used as references to evaluate samples with different characteristics. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Development, maturation and learning influence on handwriting kinematics.

    Science.gov (United States)

    Accardo, Agostino P; Genna, Mariangela; Borean, Michela

    2013-02-01

    Handwriting is the result of a process in which linguistic, psychomotor and biomechanical factors interact with physical maturation, cognitive development and learning. Digital tablets, which record the writing in real time, allow a kinematic analysis of written trace: the implemented algorithms analyze parameters as length, duration and speed of the components (trace between two pen-lifts) and strokes (trace between two minima of curvilinear velocity). The purpose of this work is to fill, at least for Italy, the lack of normative data on typical handwriting processes. This cross-sectional study will present data on 218 right-handed and Italian mother-tongue students, attending classes from 2nd to 8th grade. They performed specific tasks (tests of writing speed; transcription of a sentence accurately vs. speedily) by a digital tablet. The analysis showed many changes of the considered parameters across the classes, as in the horizontal, curvilinear mean and peak velocities of components and strokes, with higher values in the last years of schooling and a parallel decrease in the number of strokes/letter (improvement of automation). In conclusion, some of these parameters are useful for studying development and learning of writing and their values can be used as references to evaluate samples with different characteristics. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. Optimizing the way kinematical feed chains with great distance between slides are chosen for CNC machine tools

    Science.gov (United States)

    Lucian, P.; Gheorghe, S.

    2017-08-01

    This paper presents a new method, based on FRISCO formula, for optimizing the choice of the best control system for kinematical feed chains with great distance between slides used in computer numerical controlled machine tools. Such machines are usually, but not limited to, used for machining large and complex parts (mostly in the aviation industry) or complex casting molds. For such machine tools the kinematic feed chains are arranged in a dual-parallel drive structure that allows the mobile element to be moved by the two kinematical branches and their related control systems. Such an arrangement allows for high speed and high rigidity (a critical requirement for precision machining) during the machining process. A significant issue for such an arrangement it’s the ability of the two parallel control systems to follow the same trajectory accurately in order to address this issue it is necessary to achieve synchronous motion control for the two kinematical branches ensuring that the correct perpendicular position it’s kept by the mobile element during its motion on the two slides.

  18. Validation and structural analysis of the kinematics concept test

    Science.gov (United States)

    Lichtenberger, A.; Wagner, C.; Hofer, S. I.; Stern, E.; Vaterlaus, A.

    2017-06-01

    The kinematics concept test (KCT) is a multiple-choice test designed to evaluate students' conceptual understanding of kinematics at the high school level. The test comprises 49 multiple-choice items about velocity and acceleration, which are based on seven kinematic concepts and which make use of three different representations. In the first part of this article we describe the development and the validation process of the KCT. We applied the KCT to 338 Swiss high school students who attended traditional teaching in kinematics. We analyzed the response data to provide the psychometric properties of the test. In the second part we present the results of a structural analysis of the test. An exploratory factor analysis of 664 student answers finally uncovered the seven kinematics concepts as factors. However, the analysis revealed a hierarchical structure of concepts. At the higher level, mathematical concepts group together, and then split up into physics concepts at the lower level. Furthermore, students who seem to understand a concept in one representation have difficulties transferring the concept to similar problems in another representation. Both results have implications for teaching kinematics. First, teaching mathematical concepts beforehand might be beneficial for learning kinematics. Second, instructions have to be designed to teach students the change between different representations.

  19. Validation and structural analysis of the kinematics concept test

    Directory of Open Access Journals (Sweden)

    A. Lichtenberger

    2017-04-01

    Full Text Available The kinematics concept test (KCT is a multiple-choice test designed to evaluate students’ conceptual understanding of kinematics at the high school level. The test comprises 49 multiple-choice items about velocity and acceleration, which are based on seven kinematic concepts and which make use of three different representations. In the first part of this article we describe the development and the validation process of the KCT. We applied the KCT to 338 Swiss high school students who attended traditional teaching in kinematics. We analyzed the response data to provide the psychometric properties of the test. In the second part we present the results of a structural analysis of the test. An exploratory factor analysis of 664 student answers finally uncovered the seven kinematics concepts as factors. However, the analysis revealed a hierarchical structure of concepts. At the higher level, mathematical concepts group together, and then split up into physics concepts at the lower level. Furthermore, students who seem to understand a concept in one representation have difficulties transferring the concept to similar problems in another representation. Both results have implications for teaching kinematics. First, teaching mathematical concepts beforehand might be beneficial for learning kinematics. Second, instructions have to be designed to teach students the change between different representations.

  20. Kinematic aspects of pion-nucleus elastic scattering

    International Nuclear Information System (INIS)

    Weiss, D.L.; Ernst, D.J.

    1982-01-01

    The inclusion of relativistic kinematics in the theory of elastic scattering of pions from nuclei is examined. The investigation is performed in the context of the first order impulse approximation which incorporates the following features: (1) Relative momentum are defined according to relativistic theories consistent with time reversal invariance. (2) The two-nucleon interaction is a new, multichannel, separable potential model consistent with the most recent data derived from a recent nonpotential model of Ernst and Johnson. (3) The recoil of the pion-nucleon interacting pair and its resultant nonlocality are included. (4) The Fermi integral is treated by an optimal factorization approximation. It is shown how a careful definition of an intrinsic target density leads to an unambiguous method for including the recoil of the target. The target recoil corrections are found to be large for elastic scattering from 4 He and not negligible for scattering from 12 C. Relativistic potential theory kinematics, kinematics which result from covariant reduction approaches, and kinematics which result from replacing masses by energies in nonrelativistic formulas are compared. The relativistic potential theory kinematics and covariant reduction kinematics are shown to produce different elastic scattering at all pion energies examined (T/sub π/<300 MeV). Simple extensions of nonrelativistic kinematics are found to be reasonable approximations to relativistic potential theory

  1. Kinematic design considerations for minimally invasive surgical robots: an overview.

    Science.gov (United States)

    Kuo, Chin-Hsing; Dai, Jian S; Dasgupta, Prokar

    2012-06-01

    Kinematic design is a predominant phase in the design of robotic manipulators for minimally invasive surgery (MIS). However, an extensive overview of the kinematic design issues for MIS robots is not yet available to both mechanisms and robotics communities. Hundreds of archival reports and articles on robotic systems for MIS are reviewed and studied. In particular, the kinematic design considerations and mechanism development described in the literature for existing robots are focused on. The general kinematic design goals, design requirements, and design preferences for MIS robots are defined. An MIS-specialized mechanism, namely the remote center-of-motion (RCM) mechanism, is revisited and studied. Accordingly, based on the RCM mechanism types, a classification for MIS robots is provided. A comparison between eight different RCM types is given. Finally, several open challenges for the kinematic design of MIS robotic manipulators are discussed. This work provides a detailed survey of the kinematic design of MIS robots, addresses the research opportunity in MIS robots for kinematicians, and clarifies the kinematic point of view to MIS robots as a reference for the medical community. Copyright © 2012 John Wiley & Sons, Ltd.

  2. From nearby to distant galaxies: kinematical and dynamical studies

    Science.gov (United States)

    Epinat, Benoit

    2009-09-01

    Kinematical studies of low and high redshift galaxies enables to probe galaxy formation and evolution scenarios. Integral field spectroscopy is a powerful tool to study with accuracy nearby galaxies kinematics. Recent observations also gives a new 2D vision of high redshift galaxies kinematics. This work mostly relies on the kinematical sample of galaxies GHASP. This control sample, composed of 203 local spiral and irregular galaxies in low density environments observed with Fabry-Perot techniques in the Ha line (6563 A), is by now the largest sample of Fabry-Perot data. After a revue on Fabry-Perot interferometry and a presentation of new data reduction procedures, my implications on both 3D-NTT Fabry-Perot instrument and the wide field spectrograph project (WFSpec) for galaxy evolution study with the european ELT are developed. The second section is dedicated to GHASP data. This sample have been fully reduced and analysed using new methods. The kinematical analysis of 2D kinematical maps has been undertaken with the study of the dark matter distribution, the rotation curves shape, bar signatures and the ionized gas velocity dispersion. In a third section, this local reference sample is used as a zero point for high redshift galaxies kinematical studies. The GHASP sample is projected at high redshift (z=1.7) in order to disentangle evolution effects from distance biases in high redshift galaxies kinematical data observed with SINFONI, OSIRIS and GIRAFFE. The kinematical analysis of new SINFONI high redshift observations is also presented and high redshift data found in the literature are compared with GHASP projected sample, suggesting some evolution of the galaxy dynamical support within the ages.

  3. Gait Kinematic Analysis in Water Using Wearable Inertial Magnetic Sensors.

    Directory of Open Access Journals (Sweden)

    Silvia Fantozzi

    Full Text Available Walking is one of the fundamental motor tasks executed during aquatic therapy. Previous kinematics analyses conducted using waterproofed video cameras were limited to the sagittal plane and to only one or two consecutive steps. Furthermore, the set-up and post-processing are time-consuming and thus do not allow a prompt assessment of the correct execution of the movements during the aquatic session therapy. The aim of the present study was to estimate the 3D joint kinematics of the lower limbs and thorax-pelvis joints in sagittal and frontal planes during underwater walking using wearable inertial and magnetic sensors. Eleven healthy adults were measured during walking both in shallow water and in dry-land conditions. Eight wearable inertial and magnetic sensors were inserted in waterproofed boxes and fixed to the body segments by means of elastic modular bands. A validated protocol (Outwalk was used. Gait cycles were automatically segmented and selected if relevant intraclass correlation coefficients values were higher than 0.75. A total of 704 gait cycles for the lower limb joints were normalized in time and averaged to obtain the mean cycle of each joint, among participants. The mean speed in water was 40% lower than that of the dry-land condition. Longer stride duration and shorter stride distance were found in the underwater walking. In the sagittal plane, the knee was more flexed (≈ 23° and the ankle more dorsiflexed (≈ 9° at heel strike, and the hip was more flexed at toe-off (≈ 13° in water than on land. On the frontal plane in the underwater walking, smoother joint angle patterns were observed for thorax-pelvis and hip, and ankle was more inversed at toe-off (≈ 7° and showed a more inversed mean value (≈ 7°. The results were mainly explained by the effect of the speed in the water as supported by the linear mixed models analysis performed. Thus, it seemed that the combination of speed and environment triggered

  4. Constrained posture in dentistry - a kinematic analysis of dentists.

    Science.gov (United States)

    Ohlendorf, Daniela; Erbe, Christina; Nowak, Jennifer; Hauck, Imke; Hermanns, Ingo; Ditchen, Dirk; Ellegast, Rolf; Groneberg, David A

    2017-07-05

    How a dentist works, such as the patterns of movements performed daily, is also largely affected by the workstation Dental tasks are often executed in awkward body positions, thereby causing a very high degree of strain on the corresponding muscles. The objective of this study is to detect those dental tasks, during which awkward postures occur most frequently. The isolated analysis of static postures will examine the duration for which these postures are maintained during the corresponding dental, respectively non-dental, activities. 21 (11f/10 m) dentists (age: 40.1 ± 10.4 years) participated in this study. An average dental workday was collected for every subject. To collect kinematic data of all activities, the CUELA system was used. Parallel to the kinematic examination, a detailed computer-based task analysis was conducted. Afterwards, both data sets were synchronized based on the chronological order of the postures assumed in the trunk and the head region. All tasks performed were assigned to the categories "treatment" (I), "office" (II) and "other activities" (III). The angle values of each body region (evaluation parameter) were examined and assessed corresponding to ergonomic standards. Moreover, this study placed a particular focus on static positions, which are held statically for 4 s and longer. For "treatment" (I), the entire head and trunk area is anteriorly tilted while the back is twisted to the right, in (II) and (III) the back is anteriorly tilted and twisted to the right (non-neutral position). Static positions in (I) last for 4-10s, static postures (approx. 60%) can be observed while in (II) and (III) in the back area static positions for more than 30 s are most common. Moreover, in (II) the back is twisted to the right for more than 60 s in 26.8%. Awkward positions are a major part of a dentists' work. This mainly pertains to static positions of the trunk and head in contrast to "office work." These insights facilitate the quantitative

  5. The Clean Air Act and bonus allowances

    International Nuclear Information System (INIS)

    Markey, E.J.; Moorhead, C.J.

    1991-01-01

    This article discusses how utility companies can benefit in the form of bonus sulfur dioxide allowances from the Environmental Protection Agency by investing in renewable energy sources such as wind and promoting conservation. Topics discussed include the Clean Air Act Amendments, acid rain, energy conservation, renewable energy sources, and the procedure for gaining bonus allowances

  6. 36 CFR 1210.27 - Allowable costs.

    Science.gov (United States)

    2010-07-01

    ... Section 1210.27 Parks, Forests, and Public Property NATIONAL ARCHIVES AND RECORDS ADMINISTRATION GENERAL... Management § 1210.27 Allowable costs. For each kind of recipient, there is a set of Federal principles for... Educational Institutions.” The allowability of costs incurred by hospitals is determined in accordance with...

  7. 20 CFR 631.84 - Allowable projects.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Allowable projects. 631.84 Section 631.84... THE JOB TRAINING PARTNERSHIP ACT Disaster Relief Employment Assistance § 631.84 Allowable projects...) Shall be used exclusively to provide employment on projects that provide food, clothing, shelter and...

  8. 36 CFR 1207.22 - Allowable costs.

    Science.gov (United States)

    2010-07-01

    ... uniform cost accounting standards that comply with cost principles acceptable to the Federal agency. ... GOVERNMENTS Post-Award Requirements Financial Administration § 1207.22 Allowable costs. (a) Limitation on use... increment above allowable costs) to the grantee or subgrantee. (b) Applicable cost principles. For each kind...

  9. 44 CFR 13.22 - Allowable costs.

    Science.gov (United States)

    2010-10-01

    ... uniform cost accounting standards that comply with cost principles acceptable to the Federal agency. ... STATE AND LOCAL GOVERNMENTS Post-Award Requirements Financial Administration § 13.22 Allowable costs. (a... increment above allowable costs) to the grantee or subgrantee. (b) Applicable cost principles. For each kind...

  10. 24 CFR 85.22 - Allowable costs.

    Science.gov (United States)

    2010-04-01

    ... uniform cost accounting standards that comply with cost principles acceptable to the Federal agency. ... TRIBAL GOVERNMENTS Post-Award Requirements Financial Administration § 85.22 Allowable costs. (a... increment above allowable costs) to the grantee or subgrantee. (b) Applicable cost principles. For each kind...

  11. 29 CFR 97.22 - Allowable costs.

    Science.gov (United States)

    2010-07-01

    ... accounting standards that comply with cost principles acceptable to the Federal agency. [53 FR 8069, 8087... LOCAL GOVERNMENTS Post-Award Requirements Financial Administration § 97.22 Allowable costs. (a... increment above allowable costs) to the grantee or subgrantee. (b) Applicable cost principles. For each kind...

  12. 34 CFR 74.27 - Allowable costs.

    Science.gov (United States)

    2010-07-01

    ... Procedures or uniform cost accounting standards that comply with cost principles acceptable to ED. (b) The... OF HIGHER EDUCATION, HOSPITALS, AND OTHER NON-PROFIT ORGANIZATIONS Post-Award Requirements Financial... principles for determining allowable costs. Allowability of costs are determined in accordance with the cost...

  13. 22 CFR 135.22 - Allowable costs.

    Science.gov (United States)

    2010-04-01

    ... Procedures, or uniform cost accounting standards that comply with cost principles acceptable to the Federal... AGREEMENTS TO STATE AND LOCAL GOVERNMENTS Post-Award Requirements Financial Administration § 135.22 Allowable... principles. For each kind of organization, there is a set of Federal principles for determining allowable...

  14. 32 CFR 33.22 - Allowable costs.

    Science.gov (United States)

    2010-07-01

    ... accounting standards that comply with cost principles acceptable to the Federal agency. ... Post-Award Requirements Financial Administration § 33.22 Allowable costs. (a) Limitation on use of... allowable costs) to the grantee or subgrantee. (b) Applicable cost principles. For each kind of organization...

  15. 43 CFR 12.62 - Allowable costs.

    Science.gov (United States)

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Allowable costs. 12.62 Section 12.62... COST PRINCIPLES FOR ASSISTANCE PROGRAMS Uniform Administrative Requirements for Grants and Cooperative Agreements to State and Local Governments Post-Award Requirements § 12.62 Allowable costs. (a) Limitation on...

  16. 45 CFR 34.4 - Allowable claims.

    Science.gov (United States)

    2010-10-01

    ... claims for damage or loss when traveling between place of residence and duty station, or when the loss or... in exceptional cases may be allowed by the Claims Officer. (9) Transportation or travel losses... carrier, agent or agency of the government, or private conveyance, may be allowed only if the property is...

  17. Kinematics of the South Atlantic rift

    Science.gov (United States)

    Heine, C.; Zoethout, J.; Müller, R. D.

    2013-08-01

    The South Atlantic rift basin evolved as a branch of a large Jurassic-Cretaceous intraplate rift zone between the African and South American plates during the final break-up of western Gondwana. While the relative motions between South America and Africa for post-break-up times are well resolved, many issues pertaining to the fit reconstruction and particularly the relation between kinematics and lithosphere dynamics during pre-break-up remain unclear in currently published plate models. We have compiled and assimilated data from these intraplated rifts and constructed a revised plate kinematic model for the pre-break-up evolution of the South Atlantic. Based on structural restoration of the conjugate South Atlantic margins and intracontinental rift basins in Africa and South America, we achieve a tight-fit reconstruction which eliminates the need for previously inferred large intracontinental shear zones, in particular in Patagonian South America. By quantitatively accounting for crustal deformation in the Central and West African Rift Zones, we have been able to indirectly construct the kinematic history of the pre-break-up evolution of the conjugate west African-Brazilian margins. Our model suggests a causal link between changes in extension direction and velocity during continental extension and the generation of marginal structures such as the enigmatic pre-salt sag basin and the São Paulo High. We model an initial E-W-directed extension between South America and Africa (fixed in present-day position) at very low extensional velocities from 140 Ma until late Hauterivian times (≈126 Ma) when rift activity along in the equatorial Atlantic domain started to increase significantly. During this initial ≈14 Myr-long stretching episode the pre-salt basin width on the conjugate Brazilian and west African margins is generated. An intermediate stage between ≈126 Ma and base Aptian is characterised by strain localisation, rapid lithospheric weakening in the

  18. The effect of simultaneous motion presentation and graph generation in a kinematics lab

    Science.gov (United States)

    Beichner, Robert J.

    Real-time microcomputer-based Lab (MBL) experiments allow students to see and, at least in kinematics exercises, feel the connection between a physical event and its graphical representation. In Brasell's (1987) examination of the sonic ranger MBL, a delay of graphing by only 20 seconds diminished the impact of the MBL exercises. This article describes a study where kinesthetic feedback was completely removed by only giving students visual replications of a motion situation. Graph production was synchronized with motion reanimation so that students still saw a moving object and its kinematics graph simultaneously. Results indicate that this technique did not have a substantial educational advantage over traditional instruction. Since Brasell and others have demonstrated the superiority of microcomputer-based labs, this may indicate that visual juxtaposition is not the relevant variable producing the educational impact of real-time MBL. Immediate student control of the physical event and its graphical representation might be what makes MBL effective and, in the case of kinematics laboratories, kinesthetic feedback could be the most important component of the MBL learning experience. Further studies are needed in order to clarify this point.

  19. Development of a Microcontroller-based Wireless Accelerometer for Kinematic Analysis

    Directory of Open Access Journals (Sweden)

    Maria Clarissa Alvarez Carasco

    2015-06-01

    Full Text Available Wireless sensor networks (WSNs allow real-time measurement and monitoring with less complexity and more efficient in terms of obtaining data when the subject is in motion. It eliminates the limitations introduced by wired connections between the sensors and the central processing unit. Although wireless technology is widely used around the world, not much has been applied for education. Through VISSER, a low cost WSN using nRF24L01+ RF transceiver that is developed to observe and analyze the kinematics of a moving object is discussed in this paper. Data acquisition and transmission is realized with the use of a low power and low cost microcontroller ATtiny85 that obtains data from the ADXL345 three-axis accelerometer. An ATtiny85 also controls the receiving module with a UART connection to the computer. Data gathered are then processed in an open-source programming language to determine properties of an object’s motion such as pitch and roll (tilt, acceleration and displacement. This paper discusses the application of the developed WSN for the kinematics analysis of a toy car moving on flat and inclined surfaces along the three axes. The developed system can be used in various motion detection and other kinematics applications, as well as physics laboratory activities for educational purposes.

  20. Integrated kinematics-kinetics-plantar pressure data analysis: a useful tool for characterizing diabetic foot biomechanics.

    Science.gov (United States)

    Sawacha, Zimi; Guarneri, Gabriella; Cristoferi, Giuseppe; Guiotto, Annamaria; Avogaro, Angelo; Cobelli, Claudio

    2012-05-01

    The fundamental cause of lower-extremity complications in diabetes is chronic hyperglycemia leading to diabetic foot ulcer pathology. While the relationship between abnormal plantar pressure distribution and plantar ulcers has been widely investigated, little is known about the role of shear stress. Moreover, the mutual relationship among plantar pressure, shear stress, and abnormal kinematics in the etiology of diabetic foot has not been established. This lack of knowledge is determined by the lack of commercially available instruments which allow such a complex analysis. This study aims to develop a method for the simultaneous assessment of kinematics, kinetics, and plantar pressure on foot subareas of diabetic subjects by means of combining three commercial systems. Data were collected during gait on 24 patients (12 controls and 12 diabetic neuropathics) with a motion capture system synchronized with two force plates and two baropodometric systems. A four segment three-dimensional foot kinematics model was adopted for the subsegment angles estimation together with a three segment model for the plantar sub-area definition during gait. The neuropathic group exhibited significantly excessive plantar pressure, ground reaction forces on each direction, and a reduced loading surface on the midfoot subsegment (p<0.04). Furthermore the same subsegment displayed excessive dorsiflexion, external rotation, and eversion (p<0.05). Initial results showed that this methodology may enable a more appropriate characterization of patients at risk of foot ulcerations, and help planning prevention programs. Copyright © 2011 Elsevier B.V. All rights reserved.

  1. Application of principal component analysis on gait kinematics in elderly women with knee osteoarthritis.

    Science.gov (United States)

    Kirkwood, Renata N; Resende, Renan A; Magalhães, Cláudio M B; Gomes, Henrique A; Mingoti, Sueli A; Sampaio, Rosana F

    2011-01-01

    The applicability of gait analysis has been implemented with the introduction of the principal component analysis (PCA), a statistical data reduction technique that allows the comparison of the whole cycle between groups of individuals. Applying PCA, to compare the kinematics of the knee joint during gait, in the frontal and sagittal planes, between a group of elderly women with and without diagnosis in the initial and moderate stages of Osteoarthritis (OA). A total of 38 elderly women (69.6±8.1 years) with knee OA and 40 asymptomatic (70.3±7.7 years) participated on this study. The kinematics was obtained using the Qualisys Pro-reflex system. The OA group showed decreased gait velocity and stride length (pgait, was the variable with higher discrimination power between groups. PCA is an effective multivariate statistical technique to analyse the kinematic gait waveform during the gait cycle. The smaller knee flexion angle in the OA group was appointed as a discriminatory factor between groups, therefore, it should be considered in the physical therapy evaluation and treatment of elderly women with knee OA.

  2. TP-Space RRT – Kinematic Path Planning of Non-Holonomic Any-Shape Vehicles

    Directory of Open Access Journals (Sweden)

    Jose Luis Blanco

    2015-05-01

    Full Text Available The autonomous navigation of vehicles typically combines two kinds of methods: a path is first planned, and then the robot is driven by a local obstacle-avoidance controller. The present work, which focuses on path planning, proposes an extension to the well-known rapidly-exploring random tree (RRT algorithm to allow its integration with a trajectory parameter-space (TP-space as an efficient method to detect collision-free, kinematically-feasible paths for arbitrarily-shaped vehicles. In contrast to original RRT, this proposal generates navigation trees, with poses as nodes, whose edges are all kinematically-feasible paths, suitable to being accurately followed by vehicles driven by pure reactive algorithms. Initial experiments demonstrate the suitability of the method with an Ackermann-steering vehicle model whose severe kinematic constraints cannot be obviated. An important result that sets this work apart from previous research is the finding that employing several families of potential trajectories to expand the tree, which can be done efficiently under the TP-space formalism, improves the optimality of the planned trajectories. A reference C++ implementation has been released as open-source.

  3. Vibrotactile discrimination in the rat whisker system is based on neuronal coding of instantaneous kinematic cues.

    Science.gov (United States)

    Waiblinger, Christian; Brugger, Dominik; Schwarz, Cornelius

    2015-04-01

    Which physical parameter of vibrissa deflections is extracted by the rodent tactile system for discrimination? Particularly, it remains unclear whether perception has access to instantaneous kinematic parameters (i.e., the details of the trajectory) or relies on temporally integration of the movement trajectory such as frequency (e.g., spectral information) and intensity (e.g., mean speed). Here, we use a novel detection of change paradigm in head-fixed rats, which presents pulsatile vibrissa stimuli in seamless sequence for discrimination. This procedure ensures that processes of decision making can directly tap into sensory signals (no memory functions involved). We find that discrimination performance based on instantaneous kinematic cues far exceeds the ones provided by frequency and intensity. Neuronal modeling based on barrel cortex single units shows that small populations of sensitive neurons provide a transient signal that optimally fits the characteristic of the subject's perception. The present study is the first to show that perceptual read-out is superior in situations allowing the subject to base perception on detailed trajectory cues, that is, instantaneous kinematic variables. A possible impact of this finding on tactile systems of other species is suggested by evidence for instantaneous coding also in primates. © The Author 2013. Published by Oxford University Press.

  4. The valuable use of Microsoft Kinect™ sensor 3D kinematic in the rehabilitation process in basketball

    Science.gov (United States)

    Braidot, Ariel; Favaretto, Guillermo; Frisoli, Melisa; Gemignani, Diego; Gumpel, Gustavo; Massuh, Roberto; Rayan, Josefina; Turin, Matías

    2016-04-01

    Subjects who practice sports either as professionals or amateurs, have a high incidence of knee injuries. There are a few publications that show studies from a kinematic point of view of lateral-structure-knee injuries, including meniscal (meniscal tears or chondral injury), without anterior cruciate ligament rupture. The use of standard motion capture systems for measuring outdoors sport is hard to implement due to many operative reasons. Recently released, the Microsoft Kinect™ is a sensor that was developed to track movements for gaming purposes and has seen an increased use in clinical applications. The fact that this device is a simple and portable tool allows the acquisition of data of sport common movements in the field. The development and testing of a set of protocols for 3D kinematic measurement using the Microsoft Kinect™ system is presented in this paper. The 3D kinematic evaluation algorithms were developed from information available and with the use of Microsoft’s Software Development Kit 1.8 (SDK). Along with this, an algorithm for calculating the lower limb joints angles was implemented. Thirty healthy adult volunteers were measured, using five different recording protocols for sport characteristic gestures which involve high knee injury risk in athletes.

  5. Kinematic, workspace and singularity analysis of a new parallel robot used in minimally invasive surgery

    Science.gov (United States)

    Stoica, Alin; Pisla, Doina; Andras, Szilaghyi; Gherman, Bogdan; Gyurka, Bela-Zoltan; Plitea, Nicolae

    2013-03-01

    In the last ten years, due to development in robotic assisted surgery, the minimally invasive surgery has greatly changed. Until now, the vast majority of robots used in surgery, have serial structures. Due to the orientation parallel module, the structure is able to reduce the pressure exerted on the entrance point in the patient's abdominal wall. The parallel robot can also handle both a laparoscope as well an active instrument for different surgical procedures. The advantage of this parallel structure is that the geometric model has been obtained through an analytical approach. The kinematic modelling of a new parallel architecture, the inverse and direct geometric model and the inverse and direct kinematic models for velocities and accelerations are being determined. The paper will demonstrate that with this parallel structure, one can obtain the necessary workspace required for a minimally invasive operation. The robot workspace was generated using the inverse geometric model. An indepth study of different types of singularity is performed, allowing the development of safe control algorithms of the experimental model. Some kinematic simulation results and the experimental model of the robot are presented in the paper.

  6. Design and Properties of Octaslide Redundant Parallel Kinematics

    Directory of Open Access Journals (Sweden)

    V. Bauma

    2004-01-01

    Full Text Available This paper describes the conceptual design process of OCTASLIDE redundant parallel kinematics for a machine tool. Redundantly actuated parallel kinematics is a recently developed new concept for machine tools. It enables all mechanical properties of machine tools to be improved several times simultaneously. This is particularly demonstrated on the design of the OCTASLIDE. This is a concept of a five-axis machine tool centre. The paper describes the critical initial design phases and the accessible mechanical properties. The design process has follow the newly developed design methodology for parallel kinematics machines.

  7. Fission in Inverse Kinematics: A path to new experimental observables

    Science.gov (United States)

    Caamaño, Manuel; Farget, Fanny; Ramos, Diego

    2017-11-01

    Historically, experimental fission studies were based on reactions in direct kinematics with fixed target-like fissioning systems. Besides its advantages, this technique suffers from some drawbacks such as the difficulty of producing exotic fissioning systems and the seldom measurement of the fragment atomic number. Inverse kinematic provides an alternative to ease these issues and offers a new set of experimental observables that improves our level of information about the fission process, including an unprecedented access to the scission point. In this document, we review some of the observables obtained from the experimental campaign based on inverse kinematics, performed at VAMOS/GANIL.

  8. An adaptive inverse kinematics algorithm for robot manipulators

    Science.gov (United States)

    Colbaugh, R.; Glass, K.; Seraji, H.

    1990-01-01

    An adaptive algorithm for solving the inverse kinematics problem for robot manipulators is presented. The algorithm is derived using model reference adaptive control (MRAC) theory and is computationally efficient for online applications. The scheme requires no a priori knowledge of the kinematics of the robot if Cartesian end-effector sensing is available, and it requires knowledge of only the forward kinematics if joint position sensing is used. Computer simulation results are given for the redundant seven-DOF robotics research arm, demonstrating that the proposed algorithm yields accurate joint angle trajectories for a given end-effector position/orientation trajectory.

  9. Kinematical and Dynamical Modeling of Elliptical Galaxies

    Science.gov (United States)

    Mamon, G. A.; Łokas, E.; Dekel, A.; Stoehr, F.; Cox, T. J.

    Elements of kinematical and dynamical modeling of elliptical galaxies are presented. In projection, NFW models resemble Sérsic models, but with a very narrow range of shapes (m=3±1). The total density profile of ellipticals cannot be NFW-like because the predicted local M/L and aperture velocity dispersion within an effective radius (R_e) are much lower than observed. Stars must then dominate ellipticals out to a few R_e. Fitting an NFW model to the total density profile of Sérsic+NFW (stars+dark matter [DM]) ellipticals results in very high concentration parameters, as found by X-ray observers. Kinematical modeling of ellipticals assuming an isotropic NFW DM model underestimates M/L at the virial radius by a factor of 1.6 to 2.4, because dissipationless ΛCDM halos have slightly different density profiles and slightly radial velocity anisotropy. In N-body+gas simulations of ellipticals as merger remnants of spirals embedded in DM halos, the slope of the DM density profile is steeper when the initial spiral galaxies are gas-rich. The Hansen & Moore (2006) relation between anisotropy and the slope of the density profile breaks down for gas and DM, but the stars follow an analogous relation with slightly less radial anisotropies for a given density slope. Using kurtosis (h_4) to infer anisotropy in ellipticals is dangerous, as h4 is also sensitive to small levels of rotation. The stationary Jeans equation provides accurate masses out to 8 R_e. The discrepancy between the modeling of Romanowsky et al. (2003), indicating a dearth of DM in ellipticals, and the simulations analyzed by Dekel et al. (2005), which match the spectroscopic observations of ellipticals, is partly due to radial anisotropy and to observing oblate ellipticals face-on. However, one of the 15 solutions to the orbit modeling of Romanowsky et al. is found to have an amount and concentration of DM consistent with ΛCDM predictions.

  10. Evaluation of handwriting movement kinematics: from an ecological to a magnetic resonance environment

    Directory of Open Access Journals (Sweden)

    Ambra Bisio

    2016-09-01

    Full Text Available Writing is a means of communication which requires complex motor, perceptual and cognitive skills. If one of these abilities gets lost following traumatic events or due to neurological diseases, handwriting could deteriorate. Occupational therapy practitioners provide rehabilitation services for people with impaired handwriting. However, to determine the effectiveness of handwriting interventions no studies assessed whether the proposed treatments improved the kinematics of writing movement or had an effect at the level of the central nervous system. There is need to find new quantitative methodologies able to describe the behavioral and the neural outcomes of the rehabilitative interventions for handwriting. In the present study we proposed a combined approach that allowed evaluating the kinematic parameters of handwriting movements, acquired by means of a magnetic resonance-compatible tablet, and their neural correlates obtained simultaneously from a functional magnetic resonance imaging (fMRI examination. Results showed that the system was reliable in term of reproducibility of the kinematic data during a test/re-test procedure. Further, despite the modifications with respect to an ecological writing movement condition, the kinematic parameters acquired inside the MR-environment were descriptive of individuals’ movement features. At last, the imaging protocol succeeded to show the activation of the cerebral regions associated with the production of writing movement in healthy people. From these findings, this methodology seems to be promising to evaluate the handwriting movement deficits and the potential alterations in the neural activity in those individuals who have handwriting difficulties. Finally, it would provide a mean to quantitatively assess the effect of a rehabilitative treatment.

  11. Scheme Choice and Inverse Kinematics of a Positioning System Based on a Planar Parallel Mechanism

    Directory of Open Access Journals (Sweden)

    P. A. Laryushkin

    2017-01-01

    Full Text Available Recent development of the parallel mechanisms theory has resulted in an increase of the actual machines, which are built using the conceptual schemes of such mechanisms. The advantages of parallel kinematics over conventional open-chain design, such as increased stiffness or lower inertia of moving parts, allow, in theory, higher performance rates in pick-and-place or machining applications. However, the practical usage of parallel mechanisms may be problematic due to their drawbacks, such as restricted workspace area and presence of singularities.The paper discusses a modification of the milling machine “Tetra” developed in “Modular Mechanics”, ltd. (BMSTU, which consists of two identical modules based on planar parallel kinematics mechanism. The loss of module stiffness in certain positions of the end-effector was noticed after experiments on the prototype, thus indicating the presence of singularities. Since this problem is a manifestation of fundamental properties of the chosen kinematic scheme, it was decided to change it.A scheme with three linear rails and three drives, as well as a scheme with a single rail and with four drives were considered as alternative options. The first option was discarded because it requires manufacturing a massive base plate. The second option was selected for future development. In this case, as compared to the previously known design, a configuration of the intermediate links was changed. The use of “lambda”-shaped elements makes it possible to distance the drive supports from the end-effector.For a chosen scheme an inverse kinematics problem was solved. Using constraints associated with the placement of all four drive supports on a single rail and stiffness requirements as well, a one single solution was selected among sixteen possible solutions.The further investigation will include a workspace and singularity analysis and an optimization of geometric parameters of the mechanism.

  12. Utility allowed returns and market extremes

    International Nuclear Information System (INIS)

    Murry, D.A.; Nan, G.D.; Harrington, B.M.

    1993-01-01

    In recent years interest rates have fluctuated from exceptionally high levels in the early 1980s to their current levels, the lowest in two decades. Observers and analysts generally have assumed that allowed returns by regulatory commissions follow the movement of interest rates; indeed some analysts use a risk premium method to estimate the cost of common equity, assuming a constant and linear relationship between interest rates and the cost of common equity. That suggests we could expect a relatively stable relationship between interest rates and allowed returns, as well. However, a simple comparison of allowed returns and interest rates shows that this is not the case in recent years. The relationship between market interest rates and the returns allowed by commissions varies and is obviously a great deal more complicated. Empirically, there appears to be only a narrow range where market interest rates significantly affect the allowed returns on common stock set by state commissions, at least for electric and combination utilities. If rates are at historically low levels, allowed returns based largely on market rates will hasten subsequent rate filings, and commissions appear to look beyond the low rate levels. Conversely, it appears that regulators do not let historically high market rates determine allowed returns either. At either high or low interest levels, caution seems to be the policy

  13. The future(s) of emission allowances

    International Nuclear Information System (INIS)

    Rosenzweig, K.M.; Villarreal, J.A.

    1993-01-01

    The Clean Air Act Amendments of 1990 (CAAA) established a sulfur dioxide emission allowance system to be implemented by the US Environmental Protection Agency (EPA). Under the two-phase implementation of the program, electric utilities responsible for approximately 70 percent of SO 2 emissions in the United States will be issued emission allowances, each representing authorization to emit one ton of sulfur dioxide during a specified calendar year or a later year. Allowances will be issued to utilities with electric-generating units affected by the CAAA limits, as well as to certain entities which may choose to opt-in to the program. Each utility or other emission source must hold a number of allowances at least equal to its total SO 2 emissions during any given year. Unused allowances may be sold, traded, or held in inventory for use against SO 2 emissions in future years. Anyone can buy and hold allowances, including affected utilities, non-utility companies, SO 2 allowances brokers and dealers, environmental groups, and individuals. During Phase I of the program, allowances equivalent to approximately 6.4 million tons of SO 2 emissions will be allocated annually to a group of 110 large, high-SO 2 -emitting power plants. In Phase II, virtually all power-generating utilities (representing approximately 99.4 percent of total US utility emissions) will be subject to the program. The number of allowances issued will increase to approximately 8.9 million a year, with certain special allocations raising the actual number issued to 9.48 million between the years 2000 to 2009, and 8.95 million yearly thereafter. Thus, the CAAA goal of annual emissions of 9 million tons should be achieved by 2010, when virtually all US emission sources will be participating in the program

  14. Marker-based reconstruction of the kinematics of a chain of segments: a new method that incorporates joint kinematic constraints.

    Science.gov (United States)

    Klous, Miriam; Klous, Sander

    2010-07-01

    The aim of skin-marker-based motion analysis is to reconstruct the motion of a kinematical model from noisy measured motion of skin markers. Existing kinematic models for reconstruction of chains of segments can be divided into two categories: analytical methods that do not take joint constraints into account and numerical global optimization methods that do take joint constraints into account but require numerical optimization of a large number of degrees of freedom, especially when the number of segments increases. In this study, a new and largely analytical method for a chain of rigid bodies is presented, interconnected in spherical joints (chain-method). In this method, the number of generalized coordinates to be determined through numerical optimization is three, irrespective of the number of segments. This new method is compared with the analytical method of Veldpaus et al. [1988, "A Least-Squares Algorithm for the Equiform Transformation From Spatial Marker Co-Ordinates," J. Biomech., 21, pp. 45-54] (Veldpaus-method, a method of the first category) and the numerical global optimization method of Lu and O'Connor [1999, "Bone Position Estimation From Skin-Marker Co-Ordinates Using Global Optimization With Joint Constraints," J. Biomech., 32, pp. 129-134] (Lu-method, a method of the second category) regarding the effects of continuous noise simulating skin movement artifacts and regarding systematic errors in joint constraints. The study is based on simulated data to allow a comparison of the results of the different algorithms with true (noise- and error-free) marker locations. Results indicate a clear trend that accuracy for the chain-method is higher than the Veldpaus-method and similar to the Lu-method. Because large parts of the equations in the chain-method can be solved analytically, the speed of convergence in this method is substantially higher than in the Lu-method. With only three segments, the average number of required iterations with the chain

  15. Keynes, family allowances and Keynesian economic policy

    OpenAIRE

    Pressman, Steven

    2014-01-01

    This paper provides a short history of family allowances and documents the fact that Keynes supported family allowances as early as the 1920s, continuing through the 1930s and early 1940s. Keynes saw this policy as a way to help households raise their children and also as a way to increase consumption without reducing business investment. The paper goes on to argue that a policy of family allowances is consistent with Keynesian economics. Finally, the paper uses the Luxembourg Income Study to...

  16. Kinematic amplification strategies in plants and engineering

    Science.gov (United States)

    Charpentier, Victor; Hannequart, Philippe; Adriaenssens, Sigrid; Baverel, Olivier; Viglino, Emmanuel; Eisenman, Sasha

    2017-06-01

    While plants are primarily sessile at the organismal level, they do exhibit a vast array of movements at the organ or sub-organ level. These movements can occur for reasons as diverse as seed dispersal, nutrition, protection or pollination. Their advanced mechanisms generate a myriad of movement typologies, many of which are not fully understood. In recent years, there has been a renewal of interest in understanding the mechanical behavior of plants from an engineering perspective, with an interest in developing novel applications by up-sizing these mechanisms from the micro- to the macro-scale. This literature review identifies the main strategies used by plants to create and amplify movements and anatomize the most recent mechanical understanding of compliant engineering mechanics. The paper ultimately demonstrates that plant movements, rooted in compliance and multi-functionality, can effectively inspire better kinematic/adaptive structures and materials. In plants, the actuators and the deployment structures are fused into a single system. The understanding of those natural movements therefore starts with an exploration of mechanisms at the origins of movements. Plant movements, whether slow or fast, active or passive, reversible or irreversible, are presented and detailed for their mechanical significance. With a focus on displacement amplification, the most recent promising strategies for actuation and adaptive systems are examined with respect to the mechanical principles of shape morphing plant tissues.

  17. Kinematic mental simulations in abduction and deduction.

    Science.gov (United States)

    Khemlani, Sangeet Suresh; Mackiewicz, Robert; Bucciarelli, Monica; Johnson-Laird, Philip N

    2013-10-15

    We present a theory, and its computer implementation, of how mental simulations underlie the abductions of informal algorithms and deductions from these algorithms. Three experiments tested the theory's predictions, using an environment of a single railway track and a siding. This environment is akin to a universal Turing machine, but it is simple enough for nonprogrammers to use. Participants solved problems that required use of the siding to rearrange the order of cars in a train (experiment 1). Participants abduced and described in their own words algorithms that solved such problems for trains of any length, and, as the use of simulation predicts, they favored "while-loops" over "for-loops" in their descriptions (experiment 2). Given descriptions of loops of procedures, participants deduced the consequences for given trains of six cars, doing so without access to the railway environment (experiment 3). As the theory predicts, difficulty in rearranging trains depends on the numbers of moves and cars to be moved, whereas in formulating an algorithm and deducing its consequences, it depends on the Kolmogorov complexity of the algorithm. Overall, the results corroborated the use of a kinematic mental model in creating and testing informal algorithms and showed that individuals differ reliably in the ability to carry out these tasks.

  18. Graphic kinematics, visual virtual work and elastographics.

    Science.gov (United States)

    McRobie, Allan; Konstantatou, Marina; Athanasopoulos, Georgios; Hannigan, Laura

    2017-05-01

    In this paper, recent progress in graphic statics is combined with Williot displacement diagrams to create a graphical description of both statics and kinematics for two- and three-dimensional pin-jointed trusses. We begin with reciprocal form and force diagrams. The force diagram is dissected into its component cells which are then translated relative to each other. This defines a displacement diagram which is topologically equivalent to the form diagram (the structure). The various contributions to the overall Virtual Work appear as parallelograms (for two-dimensional trusses) or parallelopipeds (for three-dimensional trusses) that separate the force and the displacement pieces. Structural mechanisms can be identified by translating the force cells such that their shared faces slide across each other without separating. Elastic solutions can be obtained by choosing parallelograms or parallelopipeds of the appropriate aspect ratio. Finally, a new type of 'elastographic' diagram-termed a deformed Maxwell-Williot diagram (two-dimensional) or a deformed Rankine-Williot diagram (three-dimensional)-is presented which combines the deflected structure with the forces carried by its members.

  19. SHIELD: Neutral Gas Kinematics and Dynamics

    Science.gov (United States)

    McNichols, Andrew T.; Teich, Yaron G.; Nims, Elise; Cannon, John M.; Adams, Elizabeth A. K.; Bernstein-Cooper, Elijah Z.; Giovanelli, Riccardo; Haynes, Martha P.; Józsa, Gyula I. G.; McQuinn, Kristen B. W.; Salzer, John J.; Skillman, Evan D.; Warren, Steven R.; Dolphin, Andrew; Elson, E. C.; Haurberg, Nathalie; Ott, Jürgen; Saintonge, Amelie; Cave, Ian; Hagen, Cedric; Huang, Shan; Janowiecki, Steven; Marshall, Melissa V.; Thomann, Clara M.; Van Sistine, Angela

    2016-11-01

    We present kinematic analyses of the 12 galaxies in the “Survey of H I in Extremely Low-mass Dwarfs” (SHIELD). We use multi-configuration interferometric observations of the H I 21 cm emission line from the Karl G. Jansky Very Large Array (VLA)22 to produce image cubes at a variety of spatial and spectral resolutions. Both two- and three-dimensional fitting techniques are employed in an attempt to derive inclination-corrected rotation curves for each galaxy. In most cases, the comparable magnitudes of velocity dispersion and projected rotation result in degeneracies that prohibit unambiguous circular velocity solutions. We thus make spatially resolved position-velocity cuts, corrected for inclination using the stellar components, to estimate the circular rotation velocities. We find {v}{circ} ≤slant 30 km s-1 for the entire survey population. Baryonic masses are calculated using single-dish H I fluxes from Arecibo and stellar masses derived from HST and Spitzer imaging. Comparison is made with total dynamical masses estimated from the position-velocity analysis. The SHIELD galaxies are then placed on the baryonic Tully-Fisher relation. There exists an empirical threshold rotational velocity, V {}{rot} < 15 km s-1, below which current observations cannot differentiate coherent rotation from pressure support. The SHIELD galaxies are representative of an important population of galaxies whose properties cannot be described by current models of rotationally dominated galaxy dynamics.

  20. Kinematics and trajectory generation for MIRADAS arms

    Science.gov (United States)

    Sabater, J.; Gómez, J. M.; Torra, J.; López, M.; Raines, S. N.; Eikenberry, S. S.

    2015-05-01

    The Mid-resolution InfRAreD Astronomical Spectrograph (MIRADAS) is a NIR multi-object spectrograph for the Gran Telescopio Canarias (GTC). The instrument has a multiplexing system (MXS) that enables the simultaneous observation of twenty objects located within its field of view. These user selected targets are acquired by twenty deployable robotic probe arms with pickoff mirror optics operating at cryogenic temperatures. The MIRADAS probe arm is a close-loop mechanism designed with optics simplicity in mind, presenting good stability when it is operated upside down. Calculating optimum collision-free trajectories requires a good knowledge of the MIRADAS arm behavior based on its geometry and its mechanical constraints. This study introduces a geometric model for the two degree-of-freedom (DoF) mechanism, including solutions for the forward and inverse kinematics problem. The concepts of zone-of-avoidance (ZoA), workspace and envelope of MIRADAS arm are presented and studied. Finally, the paper proposes two different patrolling approaches that can be exploited when planning trajectories.

  1. 29 CFR 15.22 - Allowable claims.

    Science.gov (United States)

    2010-07-01

    ... may be considered and allowed. For the purpose of subpart B of this part, an alternative work location..., including property in the custody of a carrier, an agent or agency of the Government, or the claimant. (3...

  2. Maximum allowable load on wheeled mobile manipulators

    International Nuclear Information System (INIS)

    Habibnejad Korayem, M.; Ghariblu, H.

    2003-01-01

    This paper develops a computational technique for finding the maximum allowable load of mobile manipulator during a given trajectory. The maximum allowable loads which can be achieved by a mobile manipulator during a given trajectory are limited by the number of factors; probably the dynamic properties of mobile base and mounted manipulator, their actuator limitations and additional constraints applied to resolving the redundancy are the most important factors. To resolve extra D.O.F introduced by the base mobility, additional constraint functions are proposed directly in the task space of mobile manipulator. Finally, in two numerical examples involving a two-link planar manipulator mounted on a differentially driven mobile base, application of the method to determining maximum allowable load is verified. The simulation results demonstrates the maximum allowable load on a desired trajectory has not a unique value and directly depends on the additional constraint functions which applies to resolve the motion redundancy

  3. Relationship among shoulder proprioception, kinematics, and pain after stroke

    NARCIS (Netherlands)

    Niessen, M.H.M.; Veeger, H.E.J.; Meskers, C.G.M.; Koppe, P.A.; Konijnenbelt, M.H.; Janssen, T.W.J.

    2009-01-01

    Niessen MH, Veeger DH, Meskers CG, Koppe PA, Konijnenbelt MH, Janssen TW. Relationship among shoulder proprioception, kinematics, and pain after stroke. Objective: To identify a possible relationship among chronic poststroke shoulder pain (PSSP), scapular resting pose, and shoulder proprioception.

  4. Analytical kinematics analysis and synthesis of planar mechanisms

    CERN Document Server

    Gans, Deborah

    2013-01-01

    Using computational techniques and a complex variable formulation, this book teaches the student of kinematics to handle increasingly difficult problems in both the analysis and design of mechanisms all based on the fundamental loop closure equation.

  5. IMAGES. I. Strong evolution of galaxy kinematics since z = 1

    Science.gov (United States)

    Yang, Y.; Flores, H.; Hammer, F.; Neichel, B.; Puech, M.; Nesvadba, N.; Rawat, A.; Cesarsky, C.; Lehnert, M.; Pozzetti, L.; Fuentes-Carrera, I.; Amram, P.; Balkowski, C.; Dannerbauer, H.; di Serego Alighieri, S.; Guiderdoni, B.; Kembhavi, A.; Liang, Y. C.; Östlin, G.; Ravikumar, C. D.; Vergani, D.; Vernet, J.; Wozniak, H.

    2008-01-01

    Nearly half the stellar mass of present-day spiral galaxies has formed since z = 1, and galaxy kinematics is an ideal tool to identify the underlying mechanisms responsible for the galaxy mass assembly since that epoch. Here, we present the first results of the ESO large program, “IMAGES”, which aims at obtaining robust measurements of the kinematics of distant galaxies using the multi-IFU mode of GIRAFFE on the VLT. 3D spectroscopy is essential to robustly measure the often distorted kinematics of distant galaxies (e.g., Flores et al. 2006, A&A, 455, 107). We derive the velocity fields and σ-maps of 36 galaxies at 0.4 evolution of the galaxy kinematics that we observe. Intermediate MAss Galaxy Evolution Sequence, ESO programs 174.B-0328(A), 174.B-0328(A), 174.B-0328(E).

  6. Correlation Between University Students' Kinematic Achievement and Learning Styles

    Science.gov (United States)

    Çirkinoǧlu, A. G.; Dem&ircidot, N.

    2007-04-01

    In the literature, some researches on kinematics revealed that students have many difficulties in connecting graphs and physics. Also some researches showed that the method used in classroom affects students' further learning. In this study the correlation between university students' kinematics achieve and learning style are investigated. In this purpose Kinematics Achievement Test and Learning Style Inventory were applied to 573 students enrolled in general physics 1 courses at Balikesir University in the fall semester of 2005-2006. Kinematics Test, consists of 12 multiple choose and 6 open ended questions, was developed by researchers to assess students' understanding, interpreting, and drawing graphs. Learning Style Inventory, a 24 items test including visual, auditory, and kinesthetic learning styles, was developed and used by Barsch. The data obtained from in this study were analyzed necessary statistical calculations (T-test, correlation, ANOVA, etc.) by using SPSS statistical program. Based on the research findings, the tentative recommendations are made.

  7. Kinematic fingerprint of core-collapsed globular clusters

    Science.gov (United States)

    Bianchini, P.; Webb, J. J.; Sills, A.; Vesperini, E.

    2018-03-01

    Dynamical evolution drives globular clusters towards core collapse, which strongly shapes their internal properties. Diagnostics of core collapse have so far been based on photometry only, namely on the study of the concentration of the density profiles. Here, we present a new method to robustly identify core-collapsed clusters based on the study of their stellar kinematics. We introduce the kinematic concentration parameter, ck, the ratio between the global and local degree of energy equipartition reached by a cluster, and show through extensive direct N-body simulations that clusters approaching core collapse and in the post-core collapse phase are strictly characterized by ck > 1. The kinematic concentration provides a suitable diagnostic to identify core-collapsed clusters, independent from any other previous methods based on photometry. We also explore the effects of incomplete radial and stellar mass coverage on the calculation of ck and find that our method can be applied to state-of-art kinematic data sets.

  8. Kinematically Redundant Parallel Haptic Device with Large Workspace

    Directory of Open Access Journals (Sweden)

    Han Sung Kim

    2012-12-01

    Full Text Available In this paper, a kinematically redundant parallel haptic device with large workspace is presented. The haptic device has a similar kinematic structure to the well-known Delta manipulator. However, it has a special arrangement of actuators and one redundant actuator added to the third leg. The proposed haptic device has essentially 4-DOF, however, only three translational DOF are used for 3-DOF positioning and force reflection, and one rotational DOF by the redundant actuator is used to increase well-conditioned workspace. If the redundant actuator's angle is controlled to follow x and y position, the haptic device has a large cylindrical workspace and can maintain good kinematic and statics performance over the whole workspace. The kinematics and workspace are analysed, and the optimal design method of finding minimum link lengths to satisfy prescribed workspace is presented. Finally, the prototype haptic device and control experiment result are presented.

  9. Assessment of hand kinematics using inertial and magnetic sensors

    NARCIS (Netherlands)

    Kortier, H.G.; Sluiter, Victor IJzebrand; Roetenberg, D.; Veltink, Petrus H.

    2014-01-01

    Background: Assessment of hand kinematics is important when evaluating hand functioning. Major drawbacks ofcurrent sensing glove systems are lack of rotational observability in particular directions, labourintensive calibration methods which are sensitive to wear and lack of an absolute hand

  10. Kinematic fingerprint of core-collapsed globular clusters

    Science.gov (United States)

    Bianchini, P.; Webb, J. J.; Sills, A.; Vesperini, E.

    2018-01-01

    Dynamical evolution drives globular clusters toward core collapse, which strongly shapes their internal properties. Diagnostics of core collapse have so far been based on photometry only, namely on the study of the concentration of the density profiles. Here we present a new method to robustly identify core-collapsed clusters based on the study of their stellar kinematics. We introduce the kinematic concentration parameter, ck, the ratio between the global and local degree of energy equipartition reached by a cluster, and show through extensive direct N-body simulations that clusters approaching core collapse and in the post-core collapse phase are strictly characterized by ck > 1. The kinematic concentration provides a suitable diagnostic to identify core-collapsed clusters, independent from any other previous methods based on photometry. We also explore the effects of incomplete radial and stellar mass coverage on the calculation of ck and find that our method can be applied to state-of-art kinematic datasets.

  11. Improving vertex position determination by using a kinematic fit

    International Nuclear Information System (INIS)

    Forden, G.E.; Saxon, D.H.

    1985-05-01

    A method is developed for improving decay vertex reconstruction by using kinematic fits. This is applied to generated charm meson decays. An improvement of 16% in the vertex position measurement along the flight path is achieved. (author)

  12. Global-local optimization of flapping kinematics in hovering flight

    KAUST Repository

    Ghommem, Mehdi

    2013-06-01

    The kinematics of a hovering wing are optimized by combining the 2-d unsteady vortex lattice method with a hybrid of global and local optimization algorithms. The objective is to minimize the required aerodynamic power under a lift constraint. The hybrid optimization is used to efficiently navigate the complex design space due to wing-wake interference present in hovering aerodynamics. The flapping wing is chosen so that its chord length and flapping frequency match the morphological and flight properties of two insects with different masses. The results suggest that imposing a delay between the different oscillatory motions defining the flapping kinematics, and controlling the way through which the wing rotates at the end of each half stroke can improve aerodynamic power under a lift constraint. Furthermore, our optimization analysis identified optimal kinematics that agree fairly well with observed insect kinematics, as well as previously published numerical results.

  13. IceBridge L0 Raw Kinematics GPS Time Codes

    Data.gov (United States)

    National Aeronautics and Space Administration — The NASA IceBridge L0 Raw Kinematics GPS Time Codes (ITKTC0) data set contains time codes generated during flights over Antarctica using the TrueTime 705-101 GPS...

  14. Kinematics of large scale asymmetric folds and associated smaller ...

    Indian Academy of Sciences (India)

    ductile structures in the Proterozoic Somnur Formation, Pranhita - Godavari valley, ... The development of structural elements and finite strain data are analysed to constrain kinematics of folds and faults at various scales within a Proterozoic ...

  15. Kinematic analysis of platform-type robotic manipulators

    Science.gov (United States)

    Shi, Xiaolun

    New methods are developed for the kinematic analysis of serial and platform-type parallel robotic manipulators, including forward and inverse kinematic solutions, singularity identifications and workspace evaluation. Differences between serial and platform-type parallel manipulators, which can provide substantially improved end-point rigidity compared with the conventional serial robotic arms, are addressed. The problem of determining the screw parameters of rigid body motion from initial and final position data is discussed, as a basis to search for a general and efficient procedure to solve the complex forward kinematics problem of platform-type manipulators. Several Screw-Theory based approaches for solving the inverse instantaneous problem of 6 DOF serial manipulators are studied and compared in terms of their computational efficiency, accuracy, sensitivity to data error and capability of dealing with singularities. A modified Vector Decomposition method is then proposed for solving the IIK problem and for singularity analysis of serial kinematic chains, the method is especially effective when applied to the wrist partitioned serial manipulators, which are essential components to any platform-type parallel manipulators. By using the data of three point positions, velocities, and accelerations of the end effector a general method is developed for solving the forward kinematics problem, including position, velocity and acceleration kinematics, of platform-type manipulators. The solution procedure can be applied to a wide variety of platform-type manipulators such as the 6 DOF Steward Platform manipulator and other models. It is found that while the solution for the forward position kinematics of a platform-type manipulator can be obtained by solving a non-linear system of equations, the closed-form solutions for forward rate and acceleration kinematics can be found by solving a system of linear equations. Based on the proposed kinematic formulations, an algorithm

  16. Quaternion-Based Conversion Formulas for Kinematic Attitude of Floating Offshore Wind Turbines (FOWT)

    Science.gov (United States)

    Li, Yugang; Fu, Gaoyong

    2018-01-01

    A floater allowing large-angle motion supporting a large payload (wind turbine and nacelle) with large aerodynamic loads high above the water surface is a great challenge because of the raised center of gravity and large overturning moment. In this paper, the conversion formulas between Euler angles and quaternions were derived, the research offered an efficient methodology without singularity to compute large-angle rigid body rotations of a FOWT, which laid the foundation for quaternion-based attitude kinematic model introduced to describe the dynamic response of the FOWT system and further solution.

  17. Singular divergence instability thresholds of kinematically constrained circulatory systems

    Energy Technology Data Exchange (ETDEWEB)

    Kirillov, O.N., E-mail: o.kirillov@hzdr.de [Magnetohydrodynamics Division, Helmholtz-Zentrum Dresden-Rossendorf, P.O. Box 510119, D-01314 Dresden (Germany); Challamel, N. [University of South Brittany, LIMATB, Lorient (France); Darve, F. [Laboratoire Sols Solides Structures, UJF-INPG-CNRS, Grenoble (France); Lerbet, J. [IBISC, Universite d' Evry Val d' Essone, 40 Rue Pelvoux, CE 1455 Courcouronnes, 91020 Evry Cedex (France); Nicot, F. [Cemagref, Unite de Recherche Erosion Torrentielle Neige et Avalanches, Grenoble (France)

    2014-01-10

    Static instability or divergence threshold of both potential and circulatory systems with kinematic constraints depends singularly on the constraints' coefficients. Particularly, the critical buckling load of the kinematically constrained Ziegler's pendulum as a function of two coefficients of the constraint is given by the Plücker conoid of degree n=2. This simple mechanical model exhibits a structural instability similar to that responsible for the Velikhov–Chandrasekhar paradox in the theory of magnetorotational instability.

  18. Numerical kinematic transformation calculations for a parallel link manipulator

    International Nuclear Information System (INIS)

    Killough, S.M.

    1993-01-01

    Parallel link manipulators are often considered for particular robotic applications because of the unique advantages they provide. Unfortunately, they have significant disadvantages with respect to calculating the kinematic transformations because of the high-order equations that must be solved. Presented is a manipulator design that exploits the mechanical advantages of parallel links yet also has a corresponding numerical kinematic solution that can be solved in real time on common microcomputers

  19. Kinematic power corrections in off-forward hard reactions.

    Science.gov (United States)

    Braun, V M; Manashov, A N

    2011-11-11

    We develop a general approach to the calculation of kinematic corrections ∝t/Q(2), m(2)/Q(2) in hard processes which involve momentum transfer from the initial to the final hadron state. As the principal result, the complete expression is derived for the time-ordered product of two electromagnetic currents that includes all kinematic corrections to twist-four accuracy. The results are immediately applicable, e.g., to the studies of deeply virtual Compton scattering.

  20. Hyperbolic pseudoinverses for kinematics in the Euclidean group

    OpenAIRE

    Donelan, P.; Selig, J. M.

    2017-01-01

    The kinematics of a robot manipulator are described in terms of the mapping connecting its joint space and the 6-dimensional Euclidean group of motions $SE(3)$. The associated Jacobian matrices map into its Lie algebra $\\mathfrak{se}(3)$, the space of twists describing infinitesimal motion of a rigid body. Control methods generally require knowledge of an inverse for the Jacobian. However for an arm with fewer or greater than six actuated joints or at singularities of the kinematic mapping th...

  1. Decoupled Closed-Form Solution for Humanoid Lower Limb Kinematics

    OpenAIRE

    Alejandro Said; Ernesto Rodriguez-Leal; Rogelio Soto; J. L. Gordillo; Leonardo Garrido

    2015-01-01

    This paper presents an explicit, omnidirectional, analytical, and decoupled closed-form solution for the lower limb kinematics of the humanoid robot NAO. The paper starts by decoupling the position and orientation analysis from the overall Denavit-Hartenberg (DH) transformation matrices. Here, the joint activation sequence for the DH matrices is based on the geometry of a triangle. Furthermore, the implementation of a forward and a reversed kinematic analysis for the support and swing phase e...

  2. Kinematics and Load Formulation of Engine Crank Mechanism

    OpenAIRE

    Nigus, Hailemariam

    2015-01-01

    International audience; This paper presents the kinematics formulation of an internal combustion engine crank mechanism. The kinematics formulation of the crank mechanism is done using vector loop method and cosine rule are applied to describe the position of the piston. Following the velocity of piston and connecting rod is performed by differentiating the position in terms of the crank angle and connecting rod angle respectively. The acceleration equation with brief form is derived from the...

  3. Harassment Origin for Kinematic Substructures in Dwarf Elliptical Galaxies?

    OpenAIRE

    Gonzalez-Garcia, A. C.; Aguerri, J. A. L.; Balcells, M.

    2005-01-01

    [EN]We have run high resolution N-body models simulating the encounter of a dwarf galaxy with a bright elliptical galaxy. The dwarf absorbs orbital angular momentum and shows counter-rotating features in the external regions of the galaxy. To explain the core-envelope kinematic decoupling observed in some dwarf galaxies in high-density environments requires nearly head-on collisions and very little dark matter bound to the dwarf. These kinematic structures appear under rather restrictive cond...

  4. Kinematic Analysis of a Partially Decoupled 3-DOF Parallel Wrist

    Directory of Open Access Journals (Sweden)

    Fan Zhang

    2015-01-01

    Full Text Available A unique spherical parallel wrist with three partially decoupled rotational degrees of freedom (DOFs is introduced in this paper. The mechanism has the significant advantages of few singularities and simple partially decoupled kinematics. A modified parallel wrist is optimized to have the least link interference workspace. Finally, the decoupled motion is studied in detail to exhibit the kinematic performance of the mechanism.

  5. Kinematic Chains in Ski Jumping In-run Posture.

    Science.gov (United States)

    Janurová, Eva; Janura, Miroslav; Cabell, Lee; Svoboda, Zdeněk; Vařeka, Ivan; Elfmark, Milan

    2013-12-18

    The concept of kinematic chains has been systematically applied to biological systems since the 1950s. The course of a ski jump can be characterized as a change between closed and open kinematic chains. The purpose of this study was to determine a relationship between adjacent segments within the ski jumper's body's kinematic chain during the in-run phase of the ski jump. The in-run positions of 267 elite male ski jumpers who participated in the FIS World Cup events in Innsbruck, Austria, between 1992 and 2001 were analyzed (656 jumps). Two-dimensional (2-D) kinematic data were collected from the bodies of the subjects. Relationships between adjacent segments of the kinematic chain in the ski jumper's body at the in-run position are greater nearer the chain's ground contact. The coefficient of determination between the ankle and knee joint angles is 0.67. Changes in the segments' positions in the kinematic chain of the ski jumper's body are stable during longitudinal assessment. Changes in shank and thigh positions, in the sense of increase or decrease, are the same.

  6. Effect of suspension kinematic on 14 DOF vehicle model

    Science.gov (United States)

    Wongpattananukul, T.; Chantharasenawong, C.

    2017-12-01

    Computer simulations play a major role in shaping modern science and engineering. They reduce time and resource consumption in new studies and designs. Vehicle simulations have been studied extensively to achieve a vehicle model used in minimum lap time solution. Simulation result accuracy depends on the abilities of these models to represent real phenomenon. Vehicles models with 7 degrees of freedom (DOF), 10 DOF and 14 DOF are normally used in optimal control to solve for minimum lap time. However, suspension kinematics are always neglected on these models. Suspension kinematics are defined as wheel movements with respect to the vehicle body. Tire forces are expressed as a function of wheel slip and wheel position. Therefore, the suspension kinematic relation is appended to the 14 DOF vehicle model to investigate its effects on the accuracy of simulate trajectory. Classical 14 DOF vehicle model is chosen as baseline model. Experiment data is collected from formula student style car test runs as baseline data for simulation and comparison between baseline model and model with suspension kinematic. Results show that in a single long turn there is an accumulated trajectory error in baseline model compared to model with suspension kinematic. While in short alternate turns, the trajectory error is much smaller. These results show that suspension kinematic had an effect on the trajectory simulation of vehicle. Which optimal control that use baseline model will result in inaccuracy control scheme.

  7. Morpho-kinematic modeling of planetary nebulae

    Science.gov (United States)

    Chan, Tsz-Pan (Henry)

    2009-11-01

    The Planetary Nebulae (PNe) are the transition phase between asymptotic giant branch (AGB) star and white dwarfs for stars with masses between 1 and 8 M⊙. They were originally thought to be well-studied and can be explained with simple models. With the advance of imaging technology especially on Space Telescope (HST), the shapes of PNe have been found to be much more complex than we assumed to be. We aimed to investigate on the basic but mysterious intrinsic three-dimensional structures using the newly developed modeling software. Astronomers usually use the morphological classification on group and classify different properties of PNe. Over the past century many attempts have been made for this classification to seek for explaining and understanding the threedimensional structure that is responsible for the observed images. There have been two beliefs in explaining the variety of shapes of PNe and among them the most amazing one is that the morphologies can be accounted by different orientations of a single structure (Khromov & Kohoutek, 1968). Motivated by the study of Ring Nebula on its intrinsic structure, we investigated the possibility that different types of morphology in PNe can be explained by a single model. We used the newly developed modeling code SHAPE (Steffen et al., 2006), which cooperates the use of spatial information as well as its kinematics, and aimed to quantitatively investigate the basic structure inside PNe. We investigated two classical nebulae: NGC 2346 and NGC 2440. We proposed a simple but adequate model for these nebulae. Stimulated optical images and the p-v arrays were derived by the modeling code SHAPE to make comparison with the observed data to seek for the correctness of the model. Hubble velocity field and inverse square law density distribution were assumed throughout the modeling process. This model provides insights in seeking further adequate intrinsic structure of PNe.

  8. Fundamental Principles of Proper Space Kinematics

    Science.gov (United States)

    Wade, Sean

    It is desirable to understand the movement of both matter and energy in the universe based upon fundamental principles of space and time. Time dilation and length contraction are features of Special Relativity derived from the observed constancy of the speed of light. Quantum Mechanics asserts that motion in the universe is probabilistic and not deterministic. While the practicality of these dissimilar theories is well established through widespread application inconsistencies in their marriage persist, marring their utility, and preventing their full expression. After identifying an error in perspective the current theories are tested by modifying logical assumptions to eliminate paradoxical contradictions. Analysis of simultaneous frames of reference leads to a new formulation of space and time that predicts the motion of both kinds of particles. Proper Space is a real, three-dimensional space clocked by proper time that is undergoing a densification at the rate of c. Coordinate transformations to a familiar object space and a mathematical stationary space clarify the counterintuitive aspects of Special Relativity. These symmetries demonstrate that within the local universe stationary observers are a forbidden frame of reference; all is in motion. In lieu of Quantum Mechanics and Uncertainty the use of the imaginary number i is restricted for application to the labeling of mass as either material or immaterial. This material phase difference accounts for both the perceived constant velocity of light and its apparent statistical nature. The application of Proper Space Kinematics will advance more accurate representations of microscopic, oscopic, and cosmological processes and serve as a foundation for further study and reflection thereafter leading to greater insight.

  9. Allowance System: Proposed acid-rain rule

    International Nuclear Information System (INIS)

    1991-12-01

    The U.S. Environmental Protection Agency (EPA) has proposed four rules containing the core acid rain requirements: the Permits Rule (40 CFR Part 72), the Allowance System Rule (40 CFR Part 73), the Continuous Emission Monitoring Rule (40 CFR Part 75), and the Excess Emissions Rule (40 CFR Part 77). EPA will also propose additional rules at a future date. These rules will include requirements for facilities that elect to opt into the Acid Rain Program (40 CFR Part 74) and for the nitrogen oxide (NOx) control program (40 CFR Part 76). The fact sheet summarizes the key components of EPA's proposed Allowance System

  10. A Novel Methodology for the Simulation of Athletic Tasks on Cadaveric Knee Joints with Respect to In Vivo Kinematics

    Science.gov (United States)

    Bates, Nathaniel A.; Nesbitt, Rebecca J.; Shearn, Jason T.; Myer, Gregory D.; Hewett, Timothy E.

    2015-01-01

    Six degree of freedom (6-DOF) robotic manipulators have simulated clinical tests and gait on cadaveric knees to examine knee biomechanics. However, these activities do not necessarily emulate the kinematics and kinetics that lead to anterior cruciate ligament (ACL) rupture. The purpose of this study was to determine the techniques needed to derive reproducible, in vitro simulations from in vivo skin-marker kinematics recorded during simulated athletic tasks. Input of raw, in vivo, skin-marker-derived motion capture kinematics consistently resulted in specimen failure. The protocol described in this study developed an in-depth methodology to adapt in vivo kinematic recordings into 6-DOF knee motion simulations for drop vertical jumps and sidestep cutting. Our simulation method repeatably produced kinetics consistent with vertical ground reaction patterns while preserving specimen integrity. Athletic task simulation represents an advancement that allows investigators to examine ACL-intact and graft biomechanics during motions that generate greater kinetics, and the athletic tasks are more representative of documented cases of ligament rupture. Establishment of baseline functional mechanics within the knee joint during athletic tasks will serve to advance the prevention, repair and rehabilitation of ACL injuries. PMID:25869454

  11. Isotropy of an Upper Limb Exoskeleton and the Kinematics and Dynamics of the Human Arm

    Directory of Open Access Journals (Sweden)

    Joel C. Perry

    2009-01-01

    shoulder and elbow, and nearly half of the total torque at the wrist. These results suggest that the majority of human arm joint torques are devoted to supporting the human arm position in space while compensating gravitational loads whereas a minor portion of the joint torques is dedicated to arm motion itself. A unique axial orientation at the base of the exoskeleton allowed the singular configuration of the shoulder joint to be moved towards the boundary of the human arm workspace while supporting 95% of the arm's workspace. At the same time, this orientation allowed the best exoskeleton manipulability at the most commonly used human arm configuration during ADLs. One of the potential implications of these results might be the need to compensate gravitational load during robotic-assistive rehabilitation treatment. Moreover, results of a manipulability analysis of the exoskeleton system indicate that the singular configuration of the exoskeleton system may be moved out of the human arm physiological workspace while maximising the overlap between the human arm and the exoskeleton workspaces. The collected database along with kinematic and dynamic analyses may provide a fundamental basis towards the development of assistive technologies for the human arm.

  12. 77 FR 34218 - Clothing Allowance; Correction

    Science.gov (United States)

    2012-06-11

    ... could be construed to impose a restriction that VA did not intend. This document corrects that error... medication would be eligible for a clothing allowance for each such appliance or medication if each appliance or medication ``[a]ffects a distinct article of clothing or outergarment.'' On November 16, 2011, VA...

  13. International carbon trade with constrained allowance choices

    NARCIS (Netherlands)

    Yu, S.; Weikard, H.P.; Zhu, X.; Ierland, van E.C.

    2017-01-01

    International carbon markets are advocated in order to involve more countries in an agreement for the mitigation of greenhouse gas emissions and to reduce the costs of mitigation. In this paper we develop a model where allowances are endogenously determined by each member of a carbon trade

  14. 20 CFR 435.27 - Allowable costs.

    Science.gov (United States)

    2010-04-01

    ... Employees' Benefits SOCIAL SECURITY ADMINISTRATION UNIFORM ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND... ORGANIZATIONS Post-Award Requirements Financial and Program Management § 435.27 Allowable costs. For each kind... accordance with the provisions of OMB Circular A-21, “Cost Principles for Educational Institutions.” (d...

  15. 22 CFR 226.27 - Allowable costs.

    Science.gov (United States)

    2010-04-01

    ... Relations AGENCY FOR INTERNATIONAL DEVELOPMENT ADMINISTRATION OF ASSISTANCE AWARDS TO U.S. NON-GOVERNMENTAL ORGANIZATIONS Post-award Requirements Financial and Program Management § 226.27 Allowable costs. For each kind... determined in accordance with the provisions of OMB Circular A-21, “Cost Principles for Educational...

  16. 10 CFR 600.317 - Allowable costs.

    Science.gov (United States)

    2010-01-01

    ... applicable cost principles; and (3) Less than the total value of the award. ... 10 Energy 4 2010-01-01 2010-01-01 false Allowable costs. 600.317 Section 600.317 Energy DEPARTMENT OF ENERGY (CONTINUED) ASSISTANCE REGULATIONS FINANCIAL ASSISTANCE RULES Administrative Requirements...

  17. 42 CFR 417.534 - Allowable costs.

    Science.gov (United States)

    2010-10-01

    ... typical “provider” costs, and costs (such as marketing, enrollment, membership, and operation of the HMO... principles applicable to provider costs, as set forth in § 417.536. (2) The allowability of other costs is determined in accordance with principles set forth in §§ 417.538 through 417.550. (3) Costs for covered...

  18. 40 CFR 35.6245 - Allowable activities.

    Science.gov (United States)

    2010-07-01

    ... STATE AND LOCAL ASSISTANCE Cooperative Agreements and Superfund State Contracts for Superfund Response Actions Support Agency Cooperative Agreements § 35.6245 Allowable activities. Support agency activities... CFR part 300), are eligible for funding under a support agency Cooperative Agreement. Participation in...

  19. 13 CFR 143.22 - Allowable costs.

    Science.gov (United States)

    2010-01-01

    ... to that circular 48 CFR part 31. Contract Cost Principles and Procedures, or uniform cost accounting... Financial Administration § 143.22 Allowable costs. (a) Limitation on use of funds. Grant funds may be used... grantee or subgrantee. (b) Applicable cost principles. For each kind of organization, there is a set of...

  20. 29 CFR 1470.22 - Allowable costs.

    Science.gov (United States)

    2010-07-01

    ... to that circular 48 CFR part 31. Contract Cost Principles and Procedures, or uniform cost accounting... Financial Administration § 1470.22 Allowable costs. (a) Limitation on use of funds. Grant funds may be used... grantee or subgrantee. (b) Applicable cost principles. For each kind of organization, there is a set of...

  1. 40 CFR 31.22 - Allowable costs.

    Science.gov (United States)

    2010-07-01

    ... accounting standards that comply with cost principles acceptable to the Federal agency. ... Requirements Financial Administration § 31.22 Allowable costs. (a) Limitation on use of funds. Grant funds may... the grantee or sub-grantee. (b) Applicable cost principles. For each kind of organization, there is a...

  2. 34 CFR 80.22 - Allowable costs.

    Science.gov (United States)

    2010-07-01

    ... CFR part 31. Contract Cost Principles and Procedures, or uniform cost accounting standards that comply... COOPERATIVE AGREEMENTS TO STATE AND LOCAL GOVERNMENTS Post-Award Requirements Financial Administration § 80.22... kind of organization, there is a set of Federal principles for determining allowable costs. For the...

  3. 38 CFR 43.22 - Allowable costs.

    Science.gov (United States)

    2010-07-01

    ... accounting standards that comply with cost principles acceptable to the Federal agency. ... Requirements Financial Administration § 43.22 Allowable costs. (a) Limitation on use of funds. Grant funds may... the grantee or subgrantee. (b) Applicable cost principles. For each kind of organization, there is a...

  4. 45 CFR 92.22 - Allowable costs.

    Science.gov (United States)

    2010-10-01

    ... to that circular 48 CFR Part 31. Contract Cost Principles and Procedures, or uniform cost accounting... Financial Administration § 92.22 Allowable costs. (a) Limitation on use of funds. Grant funds may be used... grantee or subgrantee. (b) Applicable cost principles. For each kind of organization, there is a set of...

  5. 7 CFR 3016.22 - Allowable costs.

    Science.gov (United States)

    2010-01-01

    ... uniform cost accounting standards that comply with cost principles acceptable to the Federal agency. ... Regulations of the Department of Agriculture (Continued) OFFICE OF THE CHIEF FINANCIAL OFFICER, DEPARTMENT OF... GOVERNMENTS Post-Award Requirements Financial Administration § 3016.22 Allowable costs. (a) Limitation on use...

  6. 33 CFR 136.217 - Compensation allowable.

    Science.gov (United States)

    2010-07-01

    ...) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND; CLAIMS PROCEDURES; DESIGNATION OF SOURCE; AND ADVERTISEMENT Procedures for Particular Claims § 136.217 Compensation... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Compensation allowable. 136.217...

  7. 33 CFR 136.205 - Compensation allowable.

    Science.gov (United States)

    2010-07-01

    ...) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND; CLAIMS PROCEDURES; DESIGNATION OF SOURCE; AND ADVERTISEMENT Procedures for Particular Claims § 136.205 Compensation... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Compensation allowable. 136.205...

  8. 33 CFR 136.223 - Compensation allowable.

    Science.gov (United States)

    2010-07-01

    ...) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND; CLAIMS PROCEDURES; DESIGNATION OF SOURCE; AND ADVERTISEMENT Procedures for Particular Claims § 136.223 Compensation... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Compensation allowable. 136.223...

  9. 40 CFR 258.74 - Allowable mechanisms.

    Science.gov (United States)

    2010-07-01

    ... institution, the owner or operator must obtain alternate financial assurance. (4) The owner or operator may... certified public accountant (or appropriate State agency) auditing its financial statement as required under... MUNICIPAL SOLID WASTE LANDFILLS Financial Assurance Criteria § 258.74 Allowable mechanisms. The mechanisms...

  10. 20 CFR 632.37 - Allowable costs.

    Science.gov (United States)

    2010-04-01

    ... otherwise indicated below, direct and indirect costs shall be charged in accordance with 41 CFR 29-70 and 41... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Allowable costs. 632.37 Section 632.37 Employees' Benefits EMPLOYMENT AND TRAINING ADMINISTRATION, DEPARTMENT OF LABOR INDIAN AND NATIVE AMERICAN...

  11. Numerical comparisons of ground motion predictions with kinematic rupture modeling

    Science.gov (United States)

    Yuan, Y. O.; Zurek, B.; Liu, F.; deMartin, B.; Lacasse, M. D.

    2017-12-01

    Recent advances in large-scale wave simulators allow for the computation of seismograms at unprecedented levels of detail and for areas sufficiently large to be relevant to small regional studies. In some instances, detailed information of the mechanical properties of the subsurface has been obtained from seismic exploration surveys, well data, and core analysis. Using kinematic rupture modeling, this information can be used with a wave propagation simulator to predict the ground motion that would result from an assumed fault rupture. The purpose of this work is to explore the limits of wave propagation simulators for modeling ground motion in different settings, and in particular, to explore the numerical accuracy of different methods in the presence of features that are challenging to simulate such as topography, low-velocity surface layers, and shallow sources. In the main part of this work, we use a variety of synthetic three-dimensional models and compare the relative costs and benefits of different numerical discretization methods in computing the seismograms of realistic-size models. The finite-difference method, the discontinuous-Galerkin method, and the spectral-element method are compared for a range of synthetic models having different levels of complexity such as topography, large subsurface features, low-velocity surface layers, and the location and characteristics of fault ruptures represented as an array of seismic sources. While some previous studies have already demonstrated that unstructured-mesh methods can sometimes tackle complex problems (Moczo et al.), we investigate the trade-off between unstructured-mesh methods and regular-grid methods for a broad range of models and source configurations. Finally, for comparison, our direct simulation results are briefly contrasted with those predicted by a few phenomenological ground-motion prediction equations, and a workflow for accurately predicting ground motion is proposed.

  12. Kinematic modeling of the Milky Way using the RAVE and GCS stellar surveys

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, S.; Bland-Hawthorn, J. [Sydney Institute for Astronomy, School of Physics, University of Sydney, Sydney, NSW 2006 (Australia); Binney, J. [Rudolf Peierls Center for Theoretical Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP (United Kingdom); Freeman, K. C. [RSAA Australian National University, Mount Stromlo Observatory, Cotter Road, Weston Creek, Canberra, ACT 72611 (Australia); Steinmetz, M.; Williams, M. E. K. [Leibniz Institut für Astrophysik Potsdam (AIP), An der Sterwarte 16, D-14482 Potsdam (Germany); Boeche, C.; Grebel, E. K. [Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, D-69120 Heidelberg (Germany); Bienaymé, O.; Siebert, A. [Observatoire astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, F-67000 Strasbourg (France); Gibson, B. K. [Jeremiah Horrocks Institute for Astrophysics and Super-computing, University of Central Lancashire, Preston PR1 2HE (United Kingdom); Gilmore, G. F.; Kordopatis, G. [Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA (United Kingdom); Helmi, A. [Kapteyn Astronomical Institute, University of Groningen, Postbus 800, 9700 AV Groningen (Netherlands); Munari, U. [INAF-Astronomical Observatory of Padova, I-36012 Asiago (VI) (Italy); Navarro, J. F. [University of Victoria, P.O. Box 3055, Station CSC, Victoria, BC V8W 3P6 (Canada); Parker, Q. A.; Reid, W. A. [Department of Physics and Astronomy, Macquarie University, Sydney, NSW 2109 (Australia); Seabroke, G. M. [Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking RH5 6NT (United Kingdom); Watson, F. [Australian Astronomical Observatory, P.O. Box 296, Epping, NSW 1710 (Australia); and others

    2014-09-20

    We investigate the kinematic parameters of the Milky Way disk using the Radial Velocity Experiment (RAVE) and Geneva-Copenhagen Survey (GCS) stellar surveys. We do this by fitting a kinematic model to the data and taking the selection function of the data into account. For stars in the GCS we use all phase-space coordinates, but for RAVE stars we use only (ℓ, b, v {sub los}). Using the Markov Chain Monte Carlo technique, we investigate the full posterior distributions of the parameters given the data. We investigate the age-velocity dispersion relation for the three kinematic components (σ {sub R}, σ{sub φ}, σ {sub z}), the radial dependence of the velocity dispersions, the solar peculiar motion (U {sub ☉}, V {sub ☉}, W {sub ☉}), the circular speed Θ{sub 0} at the Sun, and the fall of mean azimuthal motion with height above the midplane. We confirm that the Besançon-style Gaussian model accurately fits the GCS data but fails to match the details of the more spatially extended RAVE survey. In particular, the Shu distribution function (DF) handles noncircular orbits more accurately and provides a better fit to the kinematic data. The Gaussian DF not only fits the data poorly but systematically underestimates the fall of velocity dispersion with radius. The radial scale length of the velocity dispersion profile of the thick disk was found to be smaller than that of the thin disk. We find that correlations exist between a number of parameters, which highlights the importance of doing joint fits. The large size of the RAVE survey allows us to get precise values for most parameters. However, large systematic uncertainties remain, especially in V {sub ☉} and Θ{sub 0}. We find that, for an extended sample of stars, Θ{sub 0} is underestimated by as much as 10% if the vertical dependence of the mean azimuthal motion is neglected. Using a simple model for vertical dependence of kinematics, we find that it is possible to match the Sgr A* proper motion without

  13. Kinematic cross-correlation induces sensory integration across separate objects.

    Science.gov (United States)

    Debats, Nienke B; Ernst, Marc O; Heuer, Herbert

    2017-12-01

    In a basic cursor-control task, the perceived positions of the hand and the cursor are biased towards each other. We recently found that this phenomenon conforms to the reliability-based weighting mechanism of optimal multisensory integration. This indicates that optimal integration is not restricted to sensory signals originating from a single source, as is the prevailing view, but that it also applies to separate objects that are connected by a kinematic relation (i.e. hand and cursor). In the current study, we examined which aspects of the kinematic relation are crucial for eliciting the sensory integration: (i) the cross-correlation between kinematic variables of the hand and cursor trajectories, and/or (ii) an internal model of the hand-cursor kinematic transformation. Participants made out-and-back movements from the centre of a semicircular workspace to its boundary, after which they judged the position where either their hand or the cursor hit the boundary. We analysed the position biases and found that the integration was strong in a condition with high kinematic correlations (a straight hand trajectory was mapped to a straight cursor trajectory), that it was significantly reduced for reduced kinematic correlations (a straight hand trajectory was transformed into a curved cursor trajectory) and that it was not affected by the inability to acquire an internal model of the kinematic transformation (i.e. by the trial-to-trial variability of the cursor curvature). These findings support the idea that correlations play a crucial role in multisensory integration irrespective of the number of sensory sources involved. © 2017 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  14. Kinematic foot types in youth with equinovarus secondary to hemiplegia.

    Science.gov (United States)

    Krzak, Joseph J; Corcos, Daniel M; Damiano, Diane L; Graf, Adam; Hedeker, Donald; Smith, Peter A; Harris, Gerald F

    2015-02-01

    Elevated kinematic variability of the foot and ankle segments exists during gait among individuals with equinovarus secondary to hemiplegic cerebral palsy (CP). Clinicians have previously addressed such variability by developing classification schemes to identify subgroups of individuals based on their kinematics. To identify kinematic subgroups among youth with equinovarus secondary to CP using 3-dimensional multi-segment foot and ankle kinematics during locomotion as inputs for principal component analysis (PCA), and K-means cluster analysis. In a single assessment session, multi-segment foot and ankle kinematics using the Milwaukee Foot Model (MFM) were collected in 24 children/adolescents with equinovarus and 20 typically developing children/adolescents. PCA was used as a data reduction technique on 40 variables. K-means cluster analysis was performed on the first six principal components (PCs) which accounted for 92% of the variance of the dataset. The PCs described the location and plane of involvement in the foot and ankle. Five distinct kinematic subgroups were identified using K-means clustering. Participants with equinovarus presented with variable involvement ranging from primary hindfoot or forefoot deviations to deformtiy that included both segments in multiple planes. This study provides further evidence of the variability in foot characteristics associated with equinovarus secondary to hemiplegic CP. These findings would not have been detected using a single segment foot model. The identification of multiple kinematic subgroups with unique foot and ankle characteristics has the potential to improve treatment since similar patients within a subgroup are likely to benefit from the same intervention(s). Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Kinematic Analysis of a Posterior-stabilized Knee Prosthesis

    Science.gov (United States)

    Zhao, Zhi-Xin; Wen, Liang; Qu, Tie-Bing; Hou, Li-Li; Xiang, Dong; Bin, Jia

    2015-01-01

    Background: The goal of total knee arthroplasty (TKA) is to restore knee kinematics. Knee prosthesis design plays a very important role in successful restoration. Here, kinematics models of normal and prosthetic knees were created and validated using previously published data. Methods: Computed tomography and magnetic resonance imaging scans of a healthy, anticorrosive female cadaver were used to establish a model of the entire lower limbs, including the femur, tibia, patella, fibula, distal femur cartilage, and medial and lateral menisci, as well as the anterior cruciate, posterior cruciate, medial collateral, and lateral collateral ligaments. The data from the three-dimensional models of the normal knee joint and a posterior-stabilized (PS) knee prosthesis were imported into finite element analysis software to create the final kinematic model of the TKA prosthesis, which was then validated by comparison with a previous study. The displacement of the medial/lateral femur and the internal rotation angle of the tibia were analyzed during 0–135° flexion. Results: Both the output data trends and the measured values derived from the normal knee's kinematics model were very close to the results reported in a previous in vivo study, suggesting that this model can be used for further analyses. The PS knee prosthesis underwent an abnormal forward displacement compared with the normal knee and has insufficient, or insufficiently aggressive, “rollback” compared with the lateral femur of the normal knee. In addition, a certain degree of reverse rotation occurs during flexion of the PS knee prosthesis. Conclusions: There were still several differences between the kinematics of the PS knee prosthesis and a normal knee, suggesting room for improving the design of the PS knee prosthesis. The abnormal kinematics during early flexion shows that the design of the articular surface played a vital role in improving the kinematics of the PS knee prosthesis. PMID:25591565

  16. Kinematic Analysis of a Posterior-stabilized Knee Prosthesis

    Directory of Open Access Journals (Sweden)

    Zhi-Xin Zhao

    2015-01-01

    Full Text Available Background: The goal of total knee arthroplasty (TKA is to restore knee kinematics. Knee prosthesis design plays a very important role in successful restoration. Here, kinematics models of normal and prosthetic knees were created and validated using previously published data. Methods: Computed tomography and magnetic resonance imaging scans of a healthy, anticorrosive female cadaver were used to establish a model of the entire lower limbs, including the femur, tibia, patella, fibula, distal femur cartilage, and medial and lateral menisci, as well as the anterior cruciate, posterior cruciate, medial collateral, and lateral collateral ligaments. The data from the three-dimensional models of the normal knee joint and a posterior-stabilized (PS knee prosthesis were imported into finite element analysis software to create the final kinematic model of the TKA prosthesis, which was then validated by comparison with a previous study. The displacement of the medial/lateral femur and the internal rotation angle of the tibia were analyzed during 0-135° flexion. Results: Both the output data trends and the measured values derived from the normal knee′s kinematics model were very close to the results reported in a previous in vivo study, suggesting that this model can be used for further analyses. The PS knee prosthesis underwent an abnormal forward displacement compared with the normal knee and has insufficient, or insufficiently aggressive, "rollback" compared with the lateral femur of the normal knee. In addition, a certain degree of reverse rotation occurs during flexion of the PS knee prosthesis. Conclusions: There were still several differences between the kinematics of the PS knee prosthesis and a normal knee, suggesting room for improving the design of the PS knee prosthesis. The abnormal kinematics during early flexion shows that the design of the articular surface played a vital role in improving the kinematics of the PS knee prosthesis.

  17. Measurement of the magnetic moment of the 2$^{+}$ state in neutron-rich radioactive $^{72,74}$Zn using the transient field technique in inverse kinematics

    CERN Multimedia

    Kruecken, R; Speidel, K; Voulot, D; Neyens, G; Gernhaeuser, R A; Fraile prieto, L M; Leske, J

    We propose to measure the sign and magnitude of the g-factors of the first 2$^{+}$ states in radioactive neutron-rich $^{72,74}$Zn applying the transient field (TF) technique in inverse kinematics. The result of this experiment will allow to probe the $\

  18. Kinematic synthesis of adjustable robotic mechanisms

    Science.gov (United States)

    Chuenchom, Thatchai

    1993-01-01

    Conventional hard automation, such as a linkage-based or a cam-driven system, provides high speed capability and repeatability but not the flexibility required in many industrial applications. The conventional mechanisms, that are typically single-degree-of-freedom systems, are being increasingly replaced by multi-degree-of-freedom multi-actuators driven by logic controllers. Although this new trend in sophistication provides greatly enhanced flexibility, there are many instances where the flexibility needs are exaggerated and the associated complexity is unnecessary. Traditional mechanism-based hard automation, on the other hand, neither can fulfill multi-task requirements nor are cost-effective mainly due to lack of methods and tools to design-in flexibility. This dissertation attempts to bridge this technological gap by developing Adjustable Robotic Mechanisms (ARM's) or 'programmable mechanisms' as a middle ground between high speed hard automation and expensive serial jointed-arm robots. This research introduces the concept of adjustable robotic mechanisms towards cost-effective manufacturing automation. A generalized analytical synthesis technique has been developed to support the computational design of ARM's that lays the theoretical foundation for synthesis of adjustable mechanisms. The synthesis method developed in this dissertation, called generalized adjustable dyad and triad synthesis, advances the well-known Burmester theory in kinematics to a new level. While this method provides planar solutions, a novel patented scheme is utilized for converting prescribed three-dimensional motion specifications into sets of planar projections. This provides an analytical and a computational tool for designing adjustable mechanisms that satisfy multiple sets of three-dimensional motion specifications. Several design issues were addressed, including adjustable parameter identification, branching defect, and mechanical errors. An efficient mathematical scheme for

  19. Kinematics and hydrodynamics analysis of swimming anurans reveals striking inter-specific differences in the mechanism for producing thrust.

    Science.gov (United States)

    Richards, Christopher T

    2010-02-15

    This study aimed to compare the swimming kinematics and hydrodynamics within and among aquatic and semi-aquatic/terrestrial frogs. High-speed video was used to obtain kinematics of the leg joints and feet as animals swam freely across their natural range of speeds. Blade element analysis was then used to model the hydrodynamic thrust as a function of foot kinematics. Two purely aquatic frogs, Xenopus laevis and Hymenochirus boettgeri, were compared with two semi-aquatic/terrestrial frogs, Rana pipiens and Bufo americanus. The four species performed similarly. Among swimming strokes, peak stroke velocity ranged from 3.3+/-1.1 to 20.9+/-2.5, from 6.8+/-2.1 to 28.6+/-3.7 and from 4.9+/-0.5 to 20.9+/-4.1 body lengths per second (BL s(-1)) in X. laevis, H. boettgeri and R. pipiens, respectively (means +/- s.d.; N=4 frogs for each). B. americanus swam much more slowly at 3.1+/-0.3 to 7.0+/-2.0 BL s(-1) (N=3 frogs). Time-varying joint kinematics patterns were superficially similar among species. Because foot kinematics result from the cumulative motion of joints proximal to the feet, small differences in time-varying joint kinematics among species resulted in species-specific foot kinematics (therefore hydrodynamics) patterns. To obtain a simple measure of the hydrodynamically useful motion of the foot, this study uses 'effective foot velocity' (EFV): a measure of the component of foot velocity along the axis of swimming. Resolving EFV into translational and rotational components allows predictions of species-specific propulsion strategies. Additionally, a novel kinematic analysis is presented here that enables the partitioning of translational and rotational foot velocity into velocity components contributed by extension at each individual limb joint. Data from the kinematics analysis show that R. pipiens and B. americanus translated their feet faster than their body moved forward, resulting in positive net translational EFV. Conversely, translational EFV was slower than

  20. Making It Personal: Per Capita Carbon Allowances

    DEFF Research Database (Denmark)

    Fawcett, Tina; Hvelplund, Frede; Meyer, Niels I

    2009-01-01

    The Chapter highligts the importance of introducing new, efficient schemes for mitigation of global warming. One such scheme is Personal Carbon Allowances (PCA), whereby individuals are allotted a tradable ration of CO2 emission per year.This chapter reviews the fundamentals of PCA and analyzes i...... merits and problems. The United Kingdom and Denmark have been chosen as case studies because the energy situation and the institutional setup are quite different between the two countries....

  1. The US SO2 allowance trading program

    International Nuclear Information System (INIS)

    Ellerman, A.D.

    2001-01-01

    The US SO 2 Allowance Trading Program is the world's first large-scale application of a cap-and-trade mechanism for limiting emissions, and it is often cited as an example for the control of other pollutants and of greenhouse gases. Drawing upon experience with this novel approach to omissions control since 1995, this article makes five observations that address common misunderstandings about emissions trading and that are applicable to the control of greenhouse gases. First, emissions trading did not compromise environmental effectiveness, and even enhanced it. Second, the program works because of the simplicity of the compliance requirement, the unavoidably strict accountability of the system, and the complete flexibility given to emitting sources. All three go together to form what may be regarded as a virtuous circle. Third, despite fears to the contrary, allowance markets developed in response to trading opportunities. Fourth, the politics of allowance allocation can be helpful in overcoming objections to emission control measures. Finally, provisions for voluntary accession present problems of moral hazard that must be carefully considered. (author)

  2. Transverse masses and kinematic constraints: from the boundary to the crease

    International Nuclear Information System (INIS)

    Barr, Alan J.; Gripaios, Ben; Lester, Christopher G.

    2009-01-01

    We re-examine the kinematic variable m T2 and its relatives in the light of recent work by Cheng and Han. Their proof that m T2 admits an equivalent, but implicit, definition as the 'boundary of the region of parent and daughter masses that is kinematically consistent with the event hypothesis' is far-reaching in its consequences. We generalize their result both to simpler cases (m T , the transverse mass) and to more complex cases (m TGen ). We further note that it is possible to re-cast many existing and unpleasant proofs (e.g. those relating to the existence or properties of 'kink' and 'crease' structures in m T2 ) into almost trivial forms by using the alternative definition. Not only does this allow us to gain better understanding of those existing results, but it also allows us to write down new (and more or less explicit) definitions of (a) the variable that naturally generalizes m T2 to the case in which the parent or daughter particles are not identical, and (b) the inverses of m T and m T2 - which may be useful if daughter masses are known and bounds on parent masses are required. We note the implications that these results may have for future matrix-element likelihood techniques.

  3. Study of error modeling in kinematic calibration of parallel manipulators

    Directory of Open Access Journals (Sweden)

    Liping Wang

    2016-10-01

    Full Text Available Error modeling is the foundation of a kinematic calibration which is a main approach to assure the accuracy of parallel manipulators. This article investigates the influence of error model on the kinematic calibration of parallel manipulators. Based on the coupling analysis between error parameters, an identifiability index for evaluating the error model is proposed. Taking a 3PRS parallel manipulator as an example, three error models with different values of identifiability index are given. With the same parameter identification, measurement, and compensation method, the computer simulations and prototype experiments of the kinematic calibration with each error model are performed. The simulation and experiment results show that the kinematic calibration using the error model with a bigger value of identifiability index can lead to a better accuracy of the manipulator. Then, an approach of error modeling is proposed to obtain a bigger value of identifiability index. The study of this article is useful for error modeling in kinematic calibration of other parallel manipulators.

  4. Kinematics of geodesic flows in stringy black hole backgrounds

    International Nuclear Information System (INIS)

    Dasgupta, Anirvan; Nandan, Hemwati; Kar, Sayan

    2009-01-01

    We study the kinematics of timelike geodesic congruences in two and four dimensions in spacetime geometries representing stringy black holes. The Raychaudhuri equations for the kinematical quantities (namely, expansion, shear, and rotation) characterizing such geodesic flows are written down and subsequently solved analytically (in two dimensions) and numerically (in four dimensions) for specific geodesic flows. We compare between geodesic flows in dual (electric and magnetic) stringy black hole backgrounds in four dimensions, by showing the differences that arise in the corresponding evolutions of the kinematic variables. The crucial role of initial conditions and the spacetime curvature on the evolution of the kinematical variables is illustrated. Some novel general conclusions on caustic formation and geodesic focusing are obtained from the analytical and numerical findings. We also propose a new quantifier in terms of the time (affine parameter) of approach to a singularity, which may be used to distinguish between flows in different geometries. In summary, our quantitative findings bring out hitherto unknown features of the kinematics of geodesic flows, which, otherwise, would have remained overlooked, if we confined ourselves to only a qualitative analysis.

  5. General analytical shakedown solution for structures with kinematic hardening materials

    Science.gov (United States)

    Guo, Baofeng; Zou, Zongyuan; Jin, Miao

    2016-09-01

    The effect of kinematic hardening behavior on the shakedown behaviors of structure has been investigated by performing shakedown analysis for some specific problems. The results obtained only show that the shakedown limit loads of structures with kinematic hardening model are larger than or equal to those with perfectly plastic model of the same initial yield stress. To further investigate the rules governing the different shakedown behaviors of kinematic hardening structures, the extended shakedown theorem for limited kinematic hardening is applied, the shakedown condition is then proposed, and a general analytical solution for the structural shakedown limit load is thus derived. The analytical shakedown limit loads for fully reversed cyclic loading and non-fully reversed cyclic loading are then given based on the general solution. The resulting analytical solution is applied to some specific problems: a hollow specimen subjected to tension and torsion, a flanged pipe subjected to pressure and axial force and a square plate with small central hole subjected to biaxial tension. The results obtained are compared with those in literatures, they are consistent with each other. Based on the resulting general analytical solution, rules governing the general effects of kinematic hardening behavior on the shakedown behavior of structure are clearly.

  6. MODELING OF KINEMATICS OF A PLASTIC SHAPING AT CALIBRATION OF A THIN-WALLED PRECISION PIPE SINKING

    Directory of Open Access Journals (Sweden)

    E. D. Chertov

    2014-01-01

    Full Text Available Summary. The mathematical model of kinematics of a plastic shaping at the sinking of a thin-walled precision pipe applied to calibration of the ends of the unified elements of the pipeline of aircraft from titanic alloys and corrosion-resistant steel before assembly to the route by means of automatic argon-arc welding of ring joints is developed. For modeling, the power criterion of stability with use of kinematic possible fields of speeds is applied to receiving the top assessment of effort of deformation. The developed model of kinematics of a plastic current allows to receive power parameters of the main condition of process of calibration by sinking and can be used for the solution of a task on stability of process of deformation by results of comparison of power (power parameters for the main (steady and indignant states. Modeling is made in cylindrical system of coordinates by comparison of options of kinematic possible fields of the speeds of a current meeting a condition of incompressibility and kinematic regional conditions. The result of the modeling was selected discontinuous field of high-speed, in which the decrease outer radius (R occurs only by increasing the thickness of the pipe wall (t. For this option the size of pressure of sinking had the smallest value, therefore the chosen field of speeds closely to the valid. It is established that with increase in a step of giving 1 at calibration by the multisector tool the demanded pressure of sinking of q decreases. At an identical step of giving 1 pipe with the smaller relative thickness of (t/r needs to be calibrated the smaller pressure of sinking. With increase of a limit of fluidity at shift of material of pipe preparation pressure of sinking of (q increases.

  7. ISS Squat and Deadlift Kinematics on the Advanced Resistive Exercise Device

    Science.gov (United States)

    Newby, N.; Caldwell, E.; Sibonga, J.; Ploutz-Snyder, L.

    2014-01-01

    Visual assessment of exercise form on the Advanced Resistive Exercise Device (ARED) on orbit is difficult due to the motion of the entire device on its Vibration Isolation System (VIS). The VIS allows for two degrees of device translational motion, and one degree of rotational motion. In order to minimize the forces that the VIS must damp in these planes of motion, the floor of the ARED moves as well during exercise to reduce changes in the center of mass of the system. To help trainers and other exercise personnel better assess squat and deadlift form a tool was developed that removes the VIS motion and creates a stick figure video of the exerciser. Another goal of the study was to determine whether any useful kinematic information could be obtained from just a single camera. Finally, the use of these data may aid in the interpretation of QCT hip structure data in response to ARED exercises performed in-flight. After obtaining informed consent, four International Space Station (ISS) crewmembers participated in this investigation. Exercise was videotaped using a single camera positioned to view the side of the crewmember during exercise on the ARED. One crewmember wore reflective tape on the toe, heel, ankle, knee, hip, and shoulder joints. This technique was not available for the other three crewmembers, so joint locations were assessed and digitized frame-by-frame by lab personnel. A custom Matlab program was used to assign two-dimensional coordinates to the joint locations throughout exercise. A second custom Matlab program was used to scale the data, calculate joint angles, estimate the foot center of pressure (COP), approximate normal and shear loads, and to create the VIS motion-corrected stick figure videos. Kinematics for the squat and deadlift vary considerably for the four crewmembers in this investigation. Some have very shallow knee and hip angles, and others have quite large ranges of motion at these joints. Joint angle analysis showed that crewmembers

  8. The Mechanical Design of a Kinematic Mount for the Mid Infrared Instrument Focal Plane Module on the James Webb Space Telescope

    Science.gov (United States)

    Thelen, Michael P.; Moore, Donald M.

    2009-01-01

    The detector assembly for the Mid Infrared Instrument (MIRI) of the James Webb Space Telescope (JWST) is mechanically supported in the Focal Plane Module (FPM) Assembly with an efficient hexapod design. The kinematic mount design allows for precision adjustment of the detector boresight to assembly alignment fiducials and maintains optical alignment requirements during flight conditions of launch and cryogenic operations below 7 Kelvin. This kinematic mounting technique is able to be implemented in a variety of optical-mechanical designs and is capable of micron level adjustment control and stability over wide dynamic and temperature ranges.

  9. ASVCP guidelines: Allowable total error hematology.

    Science.gov (United States)

    Nabity, Mary B; Harr, Kendal E; Camus, Melinda S; Flatland, Bente; Vap, Linda M

    2018-02-11

    The purpose of this document is to provide total allowable error (TE a ) recommendations for commonly analyzed hematology measurands for veterinary personnel. These guidelines define relevant terminology and highlight considerations specific to hematology measurands. They also provide reasons and guidelines for using TE a in instrument performance evaluation, including recommendations for when the total observed error exceeds the recommended TE a . Biological variation-based quality specifications are briefly discussed. The appendix describes the derivation of the hematology TE a recommendations and provides resources for external quality assurance/proficiency testing programs and a worksheet for implementation of the guidelines. © 2018 American Society for Veterinary Clinical Pathology.

  10. Robust technique allowing manufacturing superoleophobic surfaces

    Science.gov (United States)

    Bormashenko, Edward; Grynyov, Roman; Chaniel, Gilad; Taitelbaum, Haim; Bormashenko, Yelena

    2013-04-01

    We report the robust technique allowing manufacturing of superhydrophobic and oleophobic (omniphobic) surfaces with industrial grade low density polyethylene. The reported process includes two stages: (1) hot embossing of polyethylene with micro-scaled steel gauzes; (2) treatment of embossed surfaces with cold radiofrequency plasma of tetrafluoromethane. The reported surfaces demonstrate not only pronounced superhydrophobicity but also superoleophobicity. Superoleophobicity results from the hierarchical nano-scaled topography of fluorinated polyethylene surface. The observed superoleophobicity is strengthened by the hydrophobic recovery. The stability of the Cassie wetting regime was studied.

  11. Kinematics, Dynamics, and Optimal Control of Pneumatic Hexapod Robot

    Directory of Open Access Journals (Sweden)

    Long Bai

    2017-01-01

    Full Text Available Pneumatic hexapod robot is driven by inert gas carried by itself, which has board application prospect in rescue operation of disaster conditions containing flammable gas. Cruising ability is main constraint for practical engineering application which is influenced by kinematics and dynamics character. The matrix operators and pseudospectral method are used to solve dynamics modeling and numerical calculation problem of robot under straight line walking. Kinematics model is numerically solved and relationship of body, joints, and drive cylinders is obtained. With dynamics model and kinematics boundary conditions, the optimal input gas pressure of leg swing and body moving in one step is obtained by pseudospectral method. According to action character of magnetic valve, calculation results of control inputs satisfy engineering design requirements, and cruising ability under finite gas is obtained.

  12. Kinematic analysis of parallel manipulators by algebraic screw theory

    CERN Document Server

    Gallardo-Alvarado, Jaime

    2016-01-01

    This book reviews the fundamentals of screw theory concerned with velocity analysis of rigid-bodies, confirmed with detailed and explicit proofs. The author additionally investigates acceleration, jerk, and hyper-jerk analyses of rigid-bodies following the trend of the velocity analysis. With the material provided in this book, readers can extend the theory of screws into the kinematics of optional order of rigid-bodies. Illustrative examples and exercises to reinforce learning are provided. Of particular note, the kinematics of emblematic parallel manipulators, such as the Delta robot as well as the original Gough and Stewart platforms are revisited applying, in addition to the theory of screws, new methods devoted to simplify the corresponding forward-displacement analysis, a challenging task for most parallel manipulators. Stands as the only book devoted to the acceleration, jerk and hyper-jerk (snap) analyses of rigid-body by means of screw theory; Provides new strategies to simplify the forward kinematic...

  13. Study of Concepts of Parallel Kinematics Machines for Advanced Manufacturing

    Directory of Open Access Journals (Sweden)

    M. Valášek

    2005-01-01

    Full Text Available This paper deals with possible new concepts for machine tools based on parallel kinematics for advanced manufacturing. Parallel kinematics machines (PKM enable the mechanical properties of manufacturing machines to be improved. This has been proven by several new machine tool concepts. However, this potential can be and must be increased by applying the principle of redundant actuation. This paper deals with the extension of the concepts of redundantly actuated parallel kinematics structures for five-sided five-axis machine tools and for a free-forming sheet metal forming machine. The design principles of previous successful PKMs are summarized and new concepts are proposed. The most important requirement criteria are summarized. The proposed concepts are qualitatively and initially quantitatively evaluated according to these criteria. 

  14. Forward kinematics analysis for a class of asymmetrical parallel manipulators

    Directory of Open Access Journals (Sweden)

    Qimin Xu

    2017-02-01

    Full Text Available This article focuses on the forward kinematic analysis of a class of asymmetrical parallel manipulators by the proposed elimination approach. To solve the key forward kinematic constraint equations with transcendental parameters of the manipulator, an improved elimination algorithm is presented. First, by analyzing the geometry structure of the manipulator, we find the inherent triangular-topology relations of the manipulator. Further, by utilizing the parameter transformation of angular, the key transcendental equations of forward kinematic analysis are formulated into compact polynomial ones. In this context, comparing with the screw approach by Gallardo-Alvarado suggested that the computation efficiency of our proposed approach is superior. Finally, an example of the asymmetrical variable geometry truss manipulator illustrates the effectiveness of the proposed approach.

  15. Nonlinear kinematic hardening under non-proportional loading

    International Nuclear Information System (INIS)

    Ottosen, N.S.

    1979-07-01

    Within the framework of conventional plasticity theory, it is first determined under which conditions Melan-Prager's and Ziegler's kinematic hardening rules result in identical material behaviour. Next, assuming initial isotropy and adopting the von Mises yield criterion, a nonlinear kinematic hardening function is proposed for prediction of metal behaviour. The model assumes that hardening at a specific stress point depends on the direction of the new incremental loading. Hereby a realistic response is obtained for general reversed loading, and a smooth behaviour is assured, even when loading deviates more and more from proportional loading and ultimately results in reversed loading. The predictions of the proposed model for non-proportional loading under plane stress conditions are compared with those of the classical linear kinematic model, the isotropic model and with published experimental data. Finally, the limitations of the proposaed model are discussed. (author)

  16. Kinematic Performances of a Novel TLPM Parallel Robot

    Directory of Open Access Journals (Sweden)

    Fu Jianxun

    2016-01-01

    Full Text Available This paper investigates the kinematic performances of kinematics, Jacobian, singularity and interferences of a novel six-degree-of freedom (DOF parallel manipulator. Analytical solutions of the forward position kinematics have been worked out. Three-dimensional Cartesian space generated by a stroke interval from lmin to lmax fulfils the point workspace are illustrated, and the reachable workspaces are obtained. The notion of pure translational Jacobian of constraint matrix is introduced, and two types of conventional singularities are analyzed. Finally, auxiliary vectors are introduced to determine the link interferences, shown that there are two kinds of interferences in the system, one is angle-interference in one limb, and the other is distance-interference in adjacent limbs.

  17. An instrumented spatial linkage for measuring knee joint kinematics.

    Science.gov (United States)

    Rosvold, Joshua M; Atarod, Mohammad; Frank, Cyril B; Shrive, Nigel G

    2016-01-01

    In this study, the design and development of a highly accurate instrumented spatial linkage (ISL) for kinematic analysis of the ovine stifle joint is described. The ovine knee is a promising biomechanical model of the human knee joint. The ISL consists of six digital rotational encoders providing six degrees of freedom (6-DOF) to its motion. The ISL makes use of the complete and parametrically continuous (CPC) kinematic modeling method to describe the kinematic relationship between encoder readings and the relative positions and orientation of its two ends. The CPC method is useful when calibrating the ISL, because a small change in parameters corresponds to a small change in calculated positions and orientations and thus a smaller optimization error, compared to other kinematic models. The ISL is attached rigidly to the femur and the tibia for motion capture, and the CPC kinematic model is then employed to transform the angle sensor readings to relative motion of the two ends of the linkage, and thereby, the stifle joint motion. The positional accuracy for ISL after calibration and optimization was 0.3±0.2mm (mean +/- standard deviation). The ISL was also evaluated dynamically to ensure that accurate results were maintained, and achieved an accuracy of 0.1mm. Compared to the traditional motion capture methods, this system provides increased accuracy, reduced processing time, and ease of use. Future work will be on the application of the ISL to the ovine gait and determination of in vivo joint motions and tissue loads. Accurate measurement of knee joint kinematics is essential in understanding injury mechanisms and development of potential preventive or treatment strategies. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Of gluons and gravitons. Exploring color-kinematics duality

    Energy Technology Data Exchange (ETDEWEB)

    Isermann, Reinke Sven

    2013-06-15

    In this thesis color-kinematics duality will be investigated. This duality is a statement about the kinematical dependence of a scattering amplitude in Yang-Mills gauge theories obeying group theoretical relations similar to that of the color gauge group. The major consequence of this duality is that gravity amplitudes can be related to a certain double copy of gauge theory amplitudes. The main focus of this thesis is on exploring the foundations of color-kinematics duality and its consequences. It is shown how color-kinematics duality can be made manifest at the one-loop level for rational amplitudes. A Lagrangian-based argument will be given for the validity of the double copy construction for these amplitudes including explicit examples at four points. Secondly, it is studied how color-kinematics duality can be used to improve powercounting in gravity theories. To this end the duality is reformulated in terms of linear maps. It is shown as an example how this can be used to derive the large BCFW shift behavior of a gravity integrand constructed through the duality to any loop order up to subtleties inherent to the duality that is addressed. As it becomes clear the duality implies massive cancellations with respect to the usual powercounting of Feynman graphs indicating that gravity theories are much better behaved than naively expected. As another example the linear map approach will be used to investigate the question of UV-finiteness of N=8 supergravity, and it is seen that the amount of cancellations depends on the exact implementation of the duality at loop level. Lastly, color-kinematics duality is considered from a Feynman-graph perspective reproducing some of the results of the earlier chapters thus giving non-trivial evidence for the duality at the loop level from a different perspective.

  19. Kinematic variables of table vault on artistic gymnastics

    Directory of Open Access Journals (Sweden)

    Sarah Maria Boldrini FERNANDES

    2016-03-01

    Full Text Available Abstract The table vault is an event of male and female Artistics Gymnastics. Although it can be performed in a variety of rotations and body positions in different phases, it can be separated in three groups: handspring, Yurchenko and Tsukahara. It is believed that kinematic variables of vault may vary according to group of vault or gymnast body position, but few studies compares the real differences among the three groups of vaults, comparing and describing the variables in different phases. Vault kinematic variables could be diversifying according to the approach or position of the vaulting, but little has been studied about the biomechanical differences, comparing and describing behaviours at different stages. The aim of this study was to organize critical, objective and to systematize the most relevant kinematic variables to performance on vaulting. A Meta analysis over the basis Pubmed, Sport Discus and Web of Science were performed about this issue. From the selected references, we described and analyzed the kinematics of the table vault. Vault can be characterized in seven phases of analysis. Most of the studies are descriptive, and some do not descript all phases. Differences among vault variables according to group vaults, technical level and gender were analysed only in recent studies. There still gaps of knowledge about kinematic variables of table vault, in order to provide comprehensive information about all possibilities of vaults in this gymnastic event. It is concluded that kinematic variables of table vault depends upon vault group and may be considered to the improvement of technical performance. More researches are needed to approach the coaching interface with biomechanics applicable knowledge.

  20. Of gluons and gravitons. Exploring color-kinematics duality

    International Nuclear Information System (INIS)

    Isermann, Reinke Sven

    2013-06-01

    In this thesis color-kinematics duality will be investigated. This duality is a statement about the kinematical dependence of a scattering amplitude in Yang-Mills gauge theories obeying group theoretical relations similar to that of the color gauge group. The major consequence of this duality is that gravity amplitudes can be related to a certain double copy of gauge theory amplitudes. The main focus of this thesis is on exploring the foundations of color-kinematics duality and its consequences. It is shown how color-kinematics duality can be made manifest at the one-loop level for rational amplitudes. A Lagrangian-based argument will be given for the validity of the double copy construction for these amplitudes including explicit examples at four points. Secondly, it is studied how color-kinematics duality can be used to improve powercounting in gravity theories. To this end the duality is reformulated in terms of linear maps. It is shown as an example how this can be used to derive the large BCFW shift behavior of a gravity integrand constructed through the duality to any loop order up to subtleties inherent to the duality that is addressed. As it becomes clear the duality implies massive cancellations with respect to the usual powercounting of Feynman graphs indicating that gravity theories are much better behaved than naively expected. As another example the linear map approach will be used to investigate the question of UV-finiteness of N=8 supergravity, and it is seen that the amount of cancellations depends on the exact implementation of the duality at loop level. Lastly, color-kinematics duality is considered from a Feynman-graph perspective reproducing some of the results of the earlier chapters thus giving non-trivial evidence for the duality at the loop level from a different perspective.

  1. Static Stiffness Modeling of Parallel Kinematics Machine Tool Joints

    Directory of Open Access Journals (Sweden)

    O. K. Akmaev

    2015-09-01

    Full Text Available The possible variants of an original parallel kinematics machine-tool structure are explored in this article. A new Hooke's universal joint design based on needle roller bearings with the ability of a preload setting is proposed. The bearing stiffness modeling is carried out using a variety of methods. The elastic deformation modeling of a Hook’s joint and a spherical rolling joint have been developed to assess the possibility of using these joints in machine tools with parallel kinematics.

  2. A Kinematic, Kevlar(registered) Suspension System for an ADR

    Science.gov (United States)

    Voellmer, George M.; Jackson, Michael L.; Shirron, Peter J.; Tuttle, James G.

    2003-01-01

    The High Resolution Airborne Wideband Camera (HAWC) and the Submillimeter And Far Infrared Experiment (SAFIRE) will use identical Adiabatic Demagnetization Refrigerators (ADR) to cool their bolometer detectors to 200mK and 100mK, respectively. In order to minimize thermal loads on the salt pill, a Kevlar@ suspension system is used to hold it in place. An innovative, kinematic suspension system is presented. The suspension system is unique in that it consists or two parts that can be assembled and tensioned offline, and later bolted onto the salt pill. The resulting assembly constrains each degree of freedom only once, yielding a kinematic, tensile structure.

  3. Kinematics of a relativistic particle with de Sitter momentum space

    Energy Technology Data Exchange (ETDEWEB)

    Arzano, Michele [Institute for Theoretical Physics and Spinoza Institute, Utrecht University, Leuvenlaan 4, Utrecht 3584 TD (Netherlands); Kowalski-Glikman, Jerzy, E-mail: marzano@uu.nl, E-mail: jkowalskiglikman@ift.uni.wroc.pl [Institute for Theoretical Physics, University of Wroclaw, Pl. Maxa Borna 9, Pl-50-204 Wroclaw (Poland)

    2011-05-21

    We discuss kinematical properties of a free relativistic particle with deformed phase space in which momentum space is given by (a submanifold of) de Sitter space. We provide a detailed derivation of the action, Hamiltonian structure and equations of motion for such a free particle. We study the action of deformed relativistic symmetries on the phase space and derive explicit formulae for the action of the deformed Poincare group. Finally we provide a discussion on parametrization of the particle worldlines stressing analogies and differences with ordinary relativistic kinematics.

  4. A kinematic study on (un)intentional imitation in bottlenose dolphins

    Science.gov (United States)

    Sartori, Luisa; Bulgheroni, Maria; Tizzi, Raffaella; Castiello, Umberto

    2015-01-01

    The aim of the present study was to investigate the effect of observing other’s movements on subsequent performance in bottlenose dolphins. The imitative ability of non-human animals has intrigued a number of researchers. So far, however, studies in dolphins have been confined to intentional imitation concerned with the explicit request to imitate other agents. In the absence of instruction to imitate, do dolphins (un)intentionally replicate other’s movement features? To test this, dolphins were filmed while reaching and touching a stimulus before and after observing another dolphin (i.e., model) performing the same action. All videos were reviewed and segmented in order to extract the relevant movements. A marker was inserted post hoc via software on the videos upon the anatomical landmark of interest (i.e., rostrum) and was tracked throughout the time course of the movement sequence. The movement was analyzed using an in-house software developed to perform two-dimensional (2D) post hoc kinematic analysis. The results indicate that dolphins’ kinematics is sensitive to other’s movement features. Movements performed for the “visuomotor priming” condition were characterized by a kinematic pattern similar to that performed by the observed dolphin (i.e., model). Addressing the issue of spontaneous imitation in bottlenose dolphins might allow ascertaining whether the potential or impulse to produce an imitative action is generated, not just when they intend to imitate, but whenever they watch another conspecific’s behavior. In closing, this will clarify whether motor representational capacity is a by-product of factors specific to humans or whether more general characteristics such as processes of associative learning prompted by high level of encephalization could help to explain the evolution of this ability. PMID:26300764

  5. A system to measure the kinematics during the entire ski jump sequence using inertial sensors.

    Science.gov (United States)

    Chardonnens, Julien; Favre, Julien; Cuendet, Florian; Gremion, Gérald; Aminian, Kamiar

    2013-01-04

    Three-dimensional analysis of the entire sequence in ski jumping is recommended when studying the kinematics or evaluating performance. Camera-based systems which allow three-dimensional kinematics measurement are complex to set-up and require extensive post-processing, usually limiting ski jumping analyses to small numbers of jumps. In this study, a simple method using a wearable inertial sensors-based system is described to measure the orientation of the lower-body segments (sacrum, thighs, shanks) and skis during the entire jump sequence. This new method combines the fusion of inertial signals and biomechanical constraints of ski jumping. Its performance was evaluated in terms of validity and sensitivity to different performances based on 22 athletes monitored during daily training. The validity of the method was assessed by comparing the inclination of the ski and the slope at landing point and reported an error of -0.2±4.8°. The validity was also assessed by comparison of characteristic angles obtained with the proposed system and reference values in the literature; the differences were smaller than 6° for 75% of the angles and smaller than 15° for 90% of the angles. The sensitivity to different performances was evaluated by comparing the angles between two groups of athletes with different jump lengths and by assessing the association between angles and jump lengths. The differences of technique observed between athletes and the associations with jumps length agreed with the literature. In conclusion, these results suggest that this system is a promising tool for a generalization of three-dimensional kinematics analysis in ski jumping. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Not all stars form in clusters - measuring the kinematics of OB associations with Gaia

    Science.gov (United States)

    Ward, Jacob L.; Kruijssen, J. M. Diederik

    2018-01-01

    It is often stated that star clusters are the fundamental units of star formation and that most (if not all) stars form in dense stellar clusters. In this monolithic formation scenario, low density OB associations are formed from the expansion of gravitationally bound clusters following gas expulsion due to stellar feedback. N-body simulations of this process show that OB associations formed this way retain signs of expansion and elevated radial anisotropy over tens of Myr. However, recent theoretical and observational studies suggest that star formation is a hierarchical process, following the fractal nature of natal molecular clouds and allowing the formation of large-scale associations in-situ. We distinguish between these two scenarios by characterising the kinematics of OB associations using the Tycho-Gaia Astrometric Solution catalogue. To this end, we quantify four key kinematic diagnostics: the number ratio of stars with positive radial velocities to those with negative radial velocities, the median radial velocity, the median radial velocity normalised by the tangential velocity, and the radial anisotropy parameter. Each quantity presents a useful diagnostic of whether the association was more compact in the past. We compare these diagnostics to models representing random motion and the expanding products of monolithic cluster formation. None of these diagnostics show evidence of expansion, either from a single cluster or multiple clusters, and the observed kinematics are better represented by a random velocity distribution. This result favours the hierarchical star formation model in which a minority of stars forms in bound clusters and large-scale, hierarchically-structured associations are formed in-situ.

  7. Kinematics fingerprints of leader and follower role-taking during cooperative joint actions.

    Science.gov (United States)

    Sacheli, Lucia Maria; Tidoni, Emmanuele; Pavone, Enea Francesco; Aglioti, Salvatore Maria; Candidi, Matteo

    2013-05-01

    Performing online complementary motor adjustments is quintessential to joint actions since it allows interacting people to coordinate efficiently and achieve a common goal. We sought to determine whether, during dyadic interactions, signaling strategies and simulative processes are differentially implemented on the basis of the interactional role played by each partner. To this aim, we recorded the kinematics of the right hand of pairs of individuals who were asked to grasp as synchronously as possible a bottle-shaped object according to an imitative or complementary action schedule. Task requirements implied an asymmetric role assignment so that participants performed the task acting either as (1) Leader (i.e., receiving auditory information regarding the goal of the task with indications about where to grasp the object) or (2) Follower (i.e., receiving instructions to coordinate their movements with their partner's by performing imitative or complementary actions). Results showed that, when acting as Leader, participants used signaling strategies to enhance the predictability of their movements. In particular, they selectively emphasized kinematic parameters and reduced movement variability to provide the partner with implicit cues regarding the action to be jointly performed. Thus, Leaders make their movements more "communicative" even when not explicitly instructed to do so. Moreover, only when acting in the role of Follower did participants tend to imitate the Leader, even in complementary actions where imitation is detrimental to joint performance. Our results show that mimicking and signaling are implemented in joint actions according to the interactional role of the agent, which in turn is reflected in the kinematics of each partner.

  8. Running in ostriches (Struthio camelus): three-dimensional joint axes alignment and joint kinematics.

    Science.gov (United States)

    Rubenson, Jonas; Lloyd, David G; Besier, Thor F; Heliams, Denham B; Fournier, Paul A

    2007-07-01

    Although locomotor kinematics in walking and running birds have been examined in studies exploring many biological aspects of bipedalism, these studies have been largely limited to two-dimensional analyses. Incorporating a five-segment, 17 degree-of-freedom (d.f.) kinematic model of the ostrich hind limb developed from anatomical specimens, we quantified the three-dimensional (3-D) joint axis alignment and joint kinematics during running (at approximately 3.3 m s(-1)) in the largest avian biped, the ostrich. Our analysis revealed that the majority of the segment motion during running in the ostrich occurs in flexion/extension. Importantly, however, the alignment of the average flexion/extension helical axes of the knee and ankle are rotated externally to the direction of travel (37 degrees and 21 degrees , respectively) so that pure flexion and extension at the knee will act to adduct and adbuct the tibiotarsus relative to the plane of movement, and pure flexion and extension at the ankle will act to abduct and adduct the tarsometatarsus relative to the plane of movement. This feature of the limb anatomy appears to provide the major lateral (non-sagittal) displacement of the lower limb necessary for steering the swinging limb clear of the stance limb and replaces what would otherwise require greater adduction/abduction and/or internal/external rotation, allowing for less complex joints, musculoskeletal geometry and neuromuscular control. Significant rotation about the joints' non-flexion/extension axes nevertheless occurs over the running stride. In particular, hip abduction and knee internal/external and varus/valgus motion may further facilitate limb clearance during the swing phase, and substantial non-flexion/extension movement at the knee is also observed during stance. Measurement of 3-D segment and joint motion in birds will be aided by the use of functionally determined axes of rotation rather than assumed axes, proving important when interpreting the

  9. Not all stars form in clusters - measuring the kinematics of OB associations with Gaia

    Science.gov (United States)

    Ward, Jacob L.; Kruijssen, J. M. Diederik

    2018-04-01

    It is often stated that star clusters are the fundamental units of star formation and that most (if not all) stars form in dense stellar clusters. In this monolithic formation scenario, low-density OB associations are formed from the expansion of gravitationally bound clusters following gas expulsion due to stellar feedback. N-body simulations of this process show that OB associations formed this way retain signs of expansion and elevated radial anisotropy over tens of Myr. However, recent theoretical and observational studies suggest that star formation is a hierarchical process, following the fractal nature of natal molecular clouds and allowing the formation of large-scale associations in situ. We distinguish between these two scenarios by characterizing the kinematics of OB associations using the Tycho-Gaia Astrometric Solution catalogue. To this end, we quantify four key kinematic diagnostics: the number ratio of stars with positive radial velocities to those with negative radial velocities, the median radial velocity, the median radial velocity normalized by the tangential velocity, and the radial anisotropy parameter. Each quantity presents a useful diagnostic of whether the association was more compact in the past. We compare these diagnostics to models representing random motion and the expanding products of monolithic cluster formation. None of these diagnostics show evidence of expansion, either from a single cluster or multiple clusters, and the observed kinematics are better represented by a random velocity distribution. This result favours the hierarchical star formation model in which a minority of stars forms in bound clusters and large-scale, hierarchically structured associations are formed in situ.

  10. Knee joint kinematics and kinetics during the hop and cut after soft tissue artifact suppression: Time to reconsider ACL injury mechanisms?

    Science.gov (United States)

    Smale, Kenneth B; Potvin, Brigitte M; Shourijeh, Mohammad S; Benoit, Daniel L

    2017-09-06

    The recent development of a soft tissue artifact (STA) suppression method allows us to re-evaluate the tibiofemoral kinematics currently linked to non-contact knee injuries. The purpose of this study was therefore to evaluate knee joint kinematics and kinetics in six degrees of freedom (DoF) during the loading phases of a jump lunge and side cut using this in silico method. Thirty-five healthy adults completed these movements and their surface marker trajectories were then scaled and processed with OpenSim's inverse kinematics (IK) and inverse dynamics tools. Knee flexion angle-dependent kinematic constraints defined based on previous bone pin (BP) marker trajectories were then applied to the OpenSim model during IK and these constrained results were then processed with the standard inverse dynamics tool. Significant differences for all hip, knee, and ankle DoF were observed after STA suppression for both the jump lunge and side cut. Using clinically relevant effect size estimates, we conclude that STA contamination had led to misclassifications in hip transverse plane angles, knee frontal and transverse plane angles, medial/lateral and distractive/compressive knee translations, and knee frontal plane moments between the NoBP and the BP IK solutions. Our results have substantial clinical implications since past research has used joint kinematics and kinetics contaminated by STA to identify risk factors for musculoskeletal injuries. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Kinematics and dynamics of a six-degree-of-freedom robot manipulator with closed kinematic chain mechanism

    Science.gov (United States)

    Nguyen, Charles C.; Pooran, Farhad J.

    1989-01-01

    This paper deals with a class of robot manipulators built based on the kinematic chain mechanism (CKCM). This class of CKCM manipulators consists of a fixed and a moving platform coupled together via a number of in-parallel actuators. A closed-form solution is derived for the inverse kinematic problem of a six-degre-of-freedom CKCM manipulator designed to study robotic applications in space. Iterative Newton-Raphson method is employed to solve the forward kinematic problem. Dynamics of the above manipulator is derived using the Lagrangian approach. Computer simulation of the dynamical equations shows that the actuating forces are strongly dependent on the mass and centroid of the robot links.

  12. 40 CFR 82.8 - Grant of essential use allowances and critical use allowances.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 17 2010-07-01 2010-07-01 false Grant of essential use allowances and critical use allowances. 82.8 Section 82.8 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Albemarle Bill Clark Pest Control, Inc. Burnside Services, Inc. Cardinal Professional Products Chemtura Corp...

  13. Kinematics and design of a class of parallel manipulators

    Science.gov (United States)

    Hertz, Roger Barry

    1998-12-01

    This dissertation is concerned with the kinematic analysis and design of a class of three degree-of-freedom, spatial parallel manipulators. The class of manipulators is characterized by two platforms, between which are three legs, each possessing a succession of revolute, spherical, and revolute joints. The class is termed the "revolute-spherical-revolute" class of parallel manipulators. Two members of this class are examined. The first mechanism is a double-octahedral variable-geometry truss, and the second is termed a double tripod. The history the mechanisms is explored---the variable-geometry truss dates back to 1984, while predecessors of the double tripod mechanism date back to 1869. This work centers on the displacement analysis of these three-degree-of-freedom mechanisms. Two types of problem are solved: the forward displacement analysis (forward kinematics) and the inverse displacement analysis (inverse kinematics). The kinematic model of the class of mechanism is general in nature. A classification scheme for the revolute-spherical-revolute class of mechanism is introduced, which uses dominant geometric features to group designs into 8 different sub-classes. The forward kinematics problem is discussed: given a set of independently controllable input variables, solve for the relative position and orientation between the two platforms. For the variable-geometry truss, the controllable input variables are assumed to be the linear (prismatic) joints. For the double tripod, the controllable input variables are the three revolute joints adjacent to the base (proximal) platform. Multiple solutions are presented to the forward kinematics problem, indicating that there are many different positions (assemblies) that the manipulator can assume with equivalent inputs. For the double tripod these solutions can be expressed as a 16th degree polynomial in one unknown, while for the variable-geometry truss there exist two 16th degree polynomials, giving rise to 256

  14. Interactive cervical motion kinematics: sensitivity, specificity and clinically significant values for identifying kinematic impairments in patients with chronic neck pain.

    Science.gov (United States)

    Sarig Bahat, Hilla; Chen, Xiaoqi; Reznik, David; Kodesh, Einat; Treleaven, Julia

    2015-04-01

    Chronic neck pain has been consistently shown to be associated with impaired kinematic control including reduced range, velocity and smoothness of cervical motion, that seem relevant to daily function as in quick neck motion in response to surrounding stimuli. The objectives of this study were: to compare interactive cervical kinematics in patients with neck pain and controls; to explore the new measures of cervical motion accuracy; and to find the sensitivity, specificity, and optimal cutoff values for defining impaired kinematics in those with neck pain. In this cross-section study, 33 patients with chronic neck pain and 22 asymptomatic controls were assessed for their cervical kinematic control using interactive virtual reality hardware and customized software utilizing a head mounted display with built-in head tracking. Outcome measures included peak and mean velocity, smoothness (represented by number of velocity peaks (NVP)), symmetry (represented by time to peak velocity percentage (TTPP)), and accuracy of cervical motion. Results demonstrated significant and strong effect-size differences in peak and mean velocities, NVP and TTPP in all directions excluding TTPP in left rotation, and good effect-size group differences in 5/8 accuracy measures. Regression results emphasized the high clinical value of neck motion velocity, with very high sensitivity and specificity (85%-100%), followed by motion smoothness, symmetry and accuracy. These finding suggest cervical kinematics should be evaluated clinically, and screened by the provided cut off values for identification of relevant impairments in those with neck pain. Such identification of presence or absence of kinematic impairments may direct treatment strategies and additional evaluation when needed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. JUSTIFICATION OF RATIONAL KINEMATIC CHARACTERISTICS OF MOLDING VIBRATING TABLE

    Directory of Open Access Journals (Sweden)

    P. G. Anofriev

    2016-12-01

    oscillators of table, which make it possible to obtain qualitative compaction of dry molding sand in the mold. Practical value. In the process of molding using the lost foam casting models the mold mass is increasing due to the layer-by-layer filling of the mold with molding sand. The change of mass characteristics of the mold requires operational change of the kinematic characteristics of the vibrating table – vibration acceleration. The proposed mathematical model allows determining the ranges of setting the frequency parameters of inertial oscillators of molding table at all stages of molding.

  16. Plate kinematics in the Cantabrian domain of the Pyrenean orogen

    Directory of Open Access Journals (Sweden)

    S. Tavani

    2012-09-01

    Full Text Available The Cantabrian domain represents the western portion of the Pyrenean orogen, in the area where the Iberian continental lithosphere was subducted toward the north underneath the transitional to oceanic lithosphere of the Bay of Biscay. There, the about 100 km of orogenic convergence have been mostly accommodated in the northern portion of the orogen (i.e. the retro wedge developed in the Bay of Biscay abyssal plain, while only crustal-scale folding with limited internal deformation occurred in the Cantabrian southern wedge (pro-wedge. Integrated meso- and macrostructural analyses and a reappraisal of available information from the transitional area between the Pyrenean and Cantabrian domains are presented in this work, allowing to set geometric and kinematic constraints on the entire Meso-Cenozoic history of the northern portion of the Iberian Plate, including subduction initiation and evolution in the western portion of the Pyrenean orogen.

    The structural record of the Late Jurassic to Early Cretaceous deformation stage, which was associated with rifting and seafloor spreading in the Bay of Biscay, indicates a ridge perpendicular (NNE-SSW oriented extension, with no evidence of relevant strike-slip components during rifting. A Cenozoic NNW-SSE oriented shortening stage followed, related to the limited (about 100 km north-directed subduction of the Iberian continental lithosphere underneath the transitional to oceanic lithosphere of the Bay of Biscay. Subduction led to the formation of the poorly-developed Cantabrian pro-wedge, which is laterally juxtaposed to the well-developed Pyrenean pro-wedge to the east. During this convergence stage, the structural framework in the Cantabrian pro-wedge, and particularly along its transition with the Pyrenean wedge to the east, was severely complicated by the reactivation of Paleozoic and Mesozoic inherited structures.

    Data presented in this work fully support the development of the

  17. Static And Kinematic Formulation Of Planar Reciprocal Assemblies

    DEFF Research Database (Denmark)

    Parigi, Dario; Kirkegaard, Poul Henning

    2013-01-01

    Planar reciprocal frames are two dimensional structures formed by elements joined together according to the principle of structural reciprocity. In this paper a rigorous formulation of the static and kinematic problem is proposed and developed by extending the work on pin-jointed assemblies...

  18. A Self-Instructional Program in Graphical Kinematics.

    Science.gov (United States)

    Gerald, John

    The self-instructional booklet is designed to teach basic concepts of graphical kinematics if a step-by-step procedure is followed through the various frames. Each frame is composed of three main parts: (1) a statement of information, (2) a problem to be solved or a statement to be answered, and (3) the correct response. The answer sheet form and…

  19. BEARINGS WITH THE BUILT IN DIAGNOSTIC AIDS AND OPERATED KINEMATICS

    Directory of Open Access Journals (Sweden)

    A. L. Savchenko

    2012-01-01

    Full Text Available The concept and possible variants of mechatronic bearings designs of the fourth generation with sensors of angular position and tiny vibroresonance drives for kinematics management during the working process, with built-in diagnostics aid functioning on the basis of the analysis of separator rotation speed fluctuations have been offered.

  20. Different Kinematics of Knees with Varus and Valgus Deformities.

    Science.gov (United States)

    Baier, C; Benditz, A; Koeck, F; Keshmiri, A; Grifka, J; Maderbacher, G

    2018-03-01

    Few data exist of kinematics of knees with varus and valgus deformities combined with osteoarthritis. The purpose of this study was to reveal different (1) tibiofemoral kinematics, (2) medial and lateral gaps, and (3) condylar liftoff of osteoarthritic knees with either varus or valgus deformity before and after total knee arthroplasty (TKA). For this purpose, 40 patients for TKA were included in this study, 23 knees with varus deformity and 17 knees with valgus deformity. All patients underwent computer navigation, and kinematics was assessed before making any cuts or releases and after implantation. Osteoarthritic knees with valgus deformity showed a significant difference in tibia rotation relative to the femur with flexion before and after TKA, whereas knees with varus deformity did not. Knees with a valgus deformity showed femoral external rotation in extension and femoral internal rotation in flexion, whereas knees with a varus deformity revealed femoral internal rotation in extension and femoral external rotation in flexion. In both groups, gaps increased after TKA. Condylar liftoff was not observed in the varus deformity group after TKA. In the valgus deformity group, condylar liftoff was detected after TKA at knee flexion of 50 degrees and more. This study revealed significant differences in tibiofemoral kinematics between osteoarthritic knees with a varus or valgus deformity before and after TKA. Valgus deformities showed a paradoxic movement pattern. These in vivo intraoperative results need to be confirmed using fluoroscopic or radiographic three-dimensional matching before and after TKA. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  1. Using Robotics in Kinematics Classes: Exploring Braking and Stopping Distances

    Science.gov (United States)

    Brockington, Guilherme; Schivani, Milton; Barscevicius, Cesar; Raquel, Talita; Pietrocola, Maurício

    2018-01-01

    Research in the field of physics teaching has revealed high school students' difficulties in establishing relations between kinematic equations and real movements. Moreover, there are well-known and significant challenges in their comprehension of graphic language content. Thus, this article explores a didactic activity which utilized robotics in…

  2. Static and kinematic formulation of planar reciprocal assemblies

    DEFF Research Database (Denmark)

    Parigi, Dario; Sassone, Mario; Kirkegaard, Poul Henning

    2014-01-01

    Planar reciprocal frames are two dimensional structures formed by elements joined together according to the principle of structural reciprocity. In this paper a rigorous formulation of the static and kinematic problem is proposed and developed extending the theory of pin-jointed assemblies...

  3. Adding Image Constraints to Inverse Kinematics for Human Motion Capture

    Science.gov (United States)

    Jaume-i-Capó, Antoni; Varona, Javier; González-Hidalgo, Manuel; Perales, Francisco J.

    2009-12-01

    In order to study human motion in biomechanical applications, a critical component is to accurately obtain the 3D joint positions of the user's body. Computer vision and inverse kinematics are used to achieve this objective without markers or special devices attached to the body. The problem of these systems is that the inverse kinematics is "blinded" with respect to the projection of body segments into the images used by the computer vision algorithms. In this paper, we present how to add image constraints to inverse kinematics in order to estimate human motion. Specifically, we explain how to define a criterion to use images in order to guide the posture reconstruction of the articulated chain. Tests with synthetic images show how the scheme performs well in an ideal situation. In order to test its potential in real situations, more experiments with task specific image sequences are also presented. By means of a quantitative study of different sequences, the results obtained show how this approach improves the performance of inverse kinematics in this application.

  4. Is Active Tectonics on Madagascar Consistent with Somalian Plate Kinematics?

    Science.gov (United States)

    Stamps, D. S.; Kreemer, C.; Rajaonarison, T. A.

    2017-12-01

    The East African Rift System (EARS) actively breaks apart the Nubian and Somalian tectonic plates. Madagascar finds itself at the easternmost boundary of the EARS, between the Rovuma block, Lwandle plate, and the Somalian plate. Earthquake focal mechanisms and N-S oriented fault structures on the continental island suggest that Madagascar is experiencing east-west oriented extension. However, some previous plate kinematic studies indicate minor compressional strains across Madagascar. This inconsistency may be due to uncertainties in Somalian plate rotation. Past estimates of the rotation of the Somalian plate suffered from a poor coverage of GPS stations, but some important new stations are now available for a re-evaluation. In this work, we revise the kinematics of the Somalian plate. We first calculate a new GPS velocity solution and perform block kinematic modeling to evaluate the Somalian plate rotation. We then estimate new Somalia-Rovuma and Somalia-Lwandle relative motions across Madagascar and evaluate whether they are consistent with GPS measurements made on the island itself, as well as with other kinematic indicators.

  5. Effect of balance exercise on selected kinematic gait variables in ...

    African Journals Online (AJOL)

    The purpose of this study was to investigate the effect of balance exercise on some selected kinematic gait parameters in patients with knee joint osteoarthritis. Forty subjects (18 men and 22 women) participated in the study.They were divided into two groups: Group 1 (experimental) that was treated with balance exercises, ...

  6. Test-retest reliability of knee kinematics measurement during gait ...

    African Journals Online (AJOL)

    ACLR) is crucial to minimize the risk of joint degeneration. To achieve this, it is essential that the chosen measurement method can accurately assess knee kinematics and detect the changes in multi-planes of motion. However to date, limited ...

  7. Kinematics and simulation methods to determine the target thickness

    International Nuclear Information System (INIS)

    Rosales, P.; Aguilar, E.F.; Martinez Q, E.

    2001-01-01

    Making use of the kinematics and of the particles energy loss two methods for calculating the thickness of a target are described. Through a computer program and other of simulation in which parameters obtained experimentally are used. Several values for a 12 C target thickness were obtained. It is presented a comparison of the obtained values with each one of the used programs. (Author)

  8. ARGOS - IV. The kinematics of the Milky Way bulge

    Science.gov (United States)

    Ness, M.; Freeman, K.; Athanassoula, E.; Wylie-de-Boer, E.; Bland-Hawthorn, J.; Asplund, M.; Lewis, G. F.; Yong, D.; Lane, R. R.; Kiss, L. L.; Ibata, R.

    2013-07-01

    We present the kinematic results from our ARGOS spectroscopic survey of the Galactic bulge of the Milky Way. Our aim is to understand the formation of the Galactic bulge. We examine the kinematics of about 17 400 stars in the bulge located within 3.5 kpc of the Galactic Centre, identified from the 28 000 star ARGOS survey. We aim to determine if the formation of the bulge has been internally driven from disc instabilities as suggested by its boxy shape, or if mergers have played a significant role as expected from lambda cold dark matter simulations. From our velocity measurements across latitudes b = -5°, - 7.5° and -10° we find the bulge to be a cylindrically rotating system that transitions smoothly out into the disc. From observations of 3 fields at b = +10, the kinematics of the bulge show North-South symmetry about the major axis. Within the bulge, we find a kinematically distinct metal-poor population ([Fe/H] ARGOS Paper III (mean [Fe/H] ≈ -0.25 and [Fe/H] ≈ +0.15, respectively) demonstrate that they are likely to share a common formation origin and are distinct from the more metal-poor populations of the thick disc and halo which are co-located inside the bulge. We do not exclude an underlying merger generated bulge component but our results favour bulge formation from instabilities in the early thin disc.

  9. Statics and kinematics of discrete Cosserat-type granular materials

    NARCIS (Netherlands)

    Kruyt, Nicolaas P.

    2003-01-01

    A theoretical framework is presented for the statics and kinematics of discrete Cosserat-type granular materials. In analogy to the force and moment equilibrium equations for particles, compatibility equations for closed loops are formulated in the two-dimensional case for relative displacements and

  10. Can co-activation reduce kinematic variability? A simulation study.

    NARCIS (Netherlands)

    Selen, L.P.J.; Beek, P.J.; van Dieen, J.H.

    2005-01-01

    Impedance modulation has been suggested as a means to suppress the effects of internal 'noise' on movement kinematics. We investigated this hypothesis in a neuro-musculo-skeletal model. A prerequisite is that the muscle model produces realistic force variability. We found that standard Hill-type

  11. Planetary Nebulae as kinematic and dynamical tracers of galaxy halos

    NARCIS (Netherlands)

    Coccato, Lodovico; Napolitano, Nicola; Arnaboldi, Magda; Cortesi, Arianna; Romanowsky, Aaron; Gerhard, Ortwin; Merrifield, Michael; Kuijken, Konrad; Freeman, Ken; Douglas, Nigel

    2015-01-01

    The kinematics and dynamical properties of galaxy halos are difficult to measure, given the faint stellar surface brightness that characterizes those regions. Gas-rich systems such as spiral galaxies can be probed using the radio emission of their gas component. Early type galaxies contain less gas,

  12. Modern techniques in galaxy kinematics : Results from planetary nebula spectroscopy

    NARCIS (Netherlands)

    Romanowsky, AJ; Douglas, NG; Kuijken, K; Arnaboldi, M; Gerssen, J; Merrifield, MR; Kwok, S; Dopita, M; Sutherland, R

    2003-01-01

    We have observed planetary nebulae (PNe) in several early-type galaxies using new techniques on 4- to 8-meter-class telescopes. We obtain the first large data sets (greater than or similar to 100 velocities each) of PN kinematics in galaxies at greater than or similar to 15 Mpc, and present some

  13. Differences in Soccer Kick Kinematics between Blind Players and Controls

    Science.gov (United States)

    Giagazoglou, Paraskevi; Katis, Athanasios; Kellis, Eleftherios; Natsikas, Christos

    2011-01-01

    The purpose of the current study was to examine the kinematic differences during instep soccer kicks between players who were blind and sighted controls. Eleven male soccer players who were blind and nine male sighted performed instep kicks under static and dynamic conditions. The results indicated significantly higher (p less than 0.05) ball…

  14. Soft tissue artifact in canine kinematic gait analysis

    NARCIS (Netherlands)

    Schwencke, M.; Smolders, L.A.; Bergknut, N.; Gustas, P.; Meij, B.P.; Hazewinkel, H.A.W.

    2012-01-01

    Vet Surg. 2012 Oct;41(7):829-37. doi: 10.1111/j.1532-950X.2012.01021.x. Soft tissue artifact in canine kinematic gait analysis. Schwencke M, Smolders LA, Bergknut N, Gustås P, Meij BP, Hazewinkel HA. Source Department of Clinical Sciences of Companion Animals,, Faculty of Veterinary Medicine,

  15. Effects of load on good morning kinematics and EMG activity

    Directory of Open Access Journals (Sweden)

    Andrew David Vigotsky

    2015-01-01

    Full Text Available Many strength and conditioning coaches utilize the good morning (GM to strengthen the hamstrings and spinal erectors. However, little research exists on its electromyography (EMG activity and kinematics, and how these variables change as a function of load. The purpose of this investigation was to examine how estimated hamstring length, integrated EMG (IEMG activity of the hamstrings and spinal erectors, and kinematics of the lumbar spine, hip, knee, and ankle are affected by changes in load. Fifteen trained male participants (age = 24.6 ± 5.3 years; body mass = 84.7 ± 11.3 kg; height = 180.9 ± 6.8 cm were recruited for this study. Participants performed five sets of the GM, utilizing 50, 60, 70, 80, and 90% of one-repetition maximum (1RM in a randomized fashion. IEMG activity of hamstrings and spinal erectors tended to increase with load. Knee flexion increased with load on all trials. Estimated hamstring length decreased with load. However, lumbar flexion, hip flexion, and plantar flexion experienced no remarkable changes between trials. These data provide insight as to how changing the load of the GM affects EMG activity, kinematic variables, and estimated hamstring length. Implications for hamstring injury prevention are discussed. More research is needed for further insight as to how load affects EMG activity and kinematics of other exercises.

  16. Hallux valgus surgery affects kinematic parameters during gait.

    Science.gov (United States)

    Klugarova, Jitka; Janura, Miroslav; Svoboda, Zdenek; Sos, Zdenek; Stergiou, Nicholas; Klugar, Miloslav

    2016-12-01

    The aim of our study was to compare spatiotemporal parameters and lower limb and pelvis kinematics during the walking in patients with hallux valgus before and after surgery and in relation to a control group. Seventeen females with hallux valgus, who underwent first metatarsal osteotomy, constituted our experimental group. The control group consisted of thirteen females. Kinematic data during walking were obtained using the Vicon MX system. Our results showed that hallux valgus before surgery affects spatiotemporal parameters and lower limb and pelvis kinematics during walking. Hallux valgus surgery further increased the differences that were present before surgery. Specifically after hallux valgus surgery, the walking speed decreased even more (p=0.09, η 2 =0.19) while step time increased (p=0.002, η 2 =0.44) on both legs. The maximum ankle plantar flexion of the operated leg during toe-off decreased to a greater extend (p=0.03, η 2 =0.26). The asymmetry in the hip and the pelvis movements in the frontal plane (present preoperatively) persisted after surgery. Hallux valgus is not an isolated problem of the first ray, which could be just surgically addressed by correcting the foot's alignment. It is a long-term progressive malfunction of the foot affecting the entire kinematic chain of the lower extremity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Kinematics of a high-redshift galaxy: A case study

    Directory of Open Access Journals (Sweden)

    Ćirković M.M.

    2000-01-01

    Full Text Available A kinematics of a z = 2.81 galaxy toward bright QSO 0528-250, as inferred from the absorption spectroscopy is discussed. There are sufficient arguments for a far-reaching conclusion that we are observing an older, uninvolved version of the local Galactic interstellar medium.

  18. A digital database of wrist bone anatomy and carpal kinematics.

    Science.gov (United States)

    Moore, Douglas C; Crisco, Joseph J; Trafton, Theodore G; Leventhal, Evan L

    2007-01-01

    The skeletal wrist consists of eight small, intricately shaped carpal bones. The motion of these bones is complex, occurs in three dimensions, and remains incompletely defined. Our previous efforts have been focused on determining the in vivo three-dimensional (3-D) kinematics of the normal and abnormal carpus. In so doing we have developed an extensive database of carpal bone anatomy and kinematics from a large number of healthy subjects. The purpose of this paper is to describe that database and to make it available to other researchers. CT volume images of both wrists from 30 healthy volunteers (15 males and 15 females) were acquired in multiple wrist positions throughout the normal range of wrist motion. The outer cortical surfaces of the carpal bones, radius and ulna, and proximal metacarpals were segmented and the 3-D motion of each bone was calculated for each wrist position. The database was constructed to include high-resolution surface models, measures of bone volume and shape, and the 3-D kinematics of each segmented bone. The database does not include soft tissues of the wrist. While there are numerous digital anatomical databases, this one is unique in that it includes a large number of subjects and it contains in vivo kinematic data as well as the bony anatomy.

  19. KINEMATIC DETERMINANTS OF EARLY ACCELERATION IN FIELD SPORT ATHLETES

    Directory of Open Access Journals (Sweden)

    Robert G. Lockie

    2003-12-01

    Full Text Available Acceleration performance is important for field sport athletes that require a high level of repeat sprint ability. Although acceleration is widely trained for, there is little evidence outlining which kinematic factors delineate between good and poor acceleration. The aim of this study was to investigate the kinematic differences between individuals with fast and slow acceleration. Twenty field sport athletes were tested for sprint ability over the first three steps of a 15m sprint. Subjects were filmed at high speed to determine a range of lower body kinematic measures. For data analysis, subjects were then divided into relatively fast (n = 10 and slow (n = 10 groups based on their horizontal velocity. Groups were then compared across kinematic measures, including stride length and frequency, to determine whether they accounted for observed differences in sprint velocity. The results showed the fast group had significantly lower (~11-13% left and right foot contact times (p < .05, and an increased stride frequency (~9%, as compared to the slow group. Knee extension was also significantly different between groups (p < .05. There was no difference found in stride length. It was concluded that those subjects who are relatively fast in early acceleration achieve this through reduced ground contact times resulting in an improved stride frequency. Training for improved acceleration should be directed towards using coaching instructions and drills that specifically train such movement adaptations

  20. Kinematic fitting of neutral current events at HERA

    International Nuclear Information System (INIS)

    Chaves, H.; Seifert, R.J.; Zech, G.

    1993-01-01

    The measurement of the scaling variables in deep inelastic scattering at HERA can be improved considerably by constraining the scattered electrons and the produced hadrons to energy-momentum conservation. It is shown how unobserved particles moving down the beam pipe and initial state radiation can be included in the kinematics. The particle momenta are adjusted in a linear least squares fit. (orig.)

  1. Motor control in complex regional pain syndrome: A kinematic analysis

    NARCIS (Netherlands)

    Schilder, J.C.M.; Schouten, A.C.; Perez, R.S.G.M.; Huygen, F.J.P.M.; Dahan, A.; Noldus, L.P.J.J.; van Hilten, J.J.; Marinus, J.

    2012-01-01

    This study evaluated movement velocity, frequency, and amplitude, as well as the number of arrests in three different subject groups, by kinematic analysis of repetitive movements during a finger tapping (FT) task. The most affected hands of 80 patients with complex regional pain syndrome (CRPS)

  2. Ambulatory Assesment of Hand Kinematics, using an instrumented glove

    NARCIS (Netherlands)

    Kortier, H.G.; Schepers, H. Martin; Sluiter, Victor IJzebrand; Veltink, Petrus H.; Leardini, A.; Stagni, R.

    2012-01-01

    Inertial and magnetic sensors, attached to various segments of the human hand, can be used to measure movements of the hand. This paper proposes a new method to assess hand kinematics by applying an Extended Kalman Filter in which prior information of the hand is fused with actual measurements

  3. Advance knowledge effects on kinematics of one-handed catching

    NARCIS (Netherlands)

    Tijtgat, P.T.L.; Bennett, S.J.; Savelsbergh, G.J.P.; de Clercq, D.; Lenoir, M.

    2010-01-01

    The purpose of this experiment was to examine the effects of advance knowledge on the kinematics of one-handed catching. Balls were launched from a distance of 8.4 m by a ball-projection machine with adjustable launching speed. Fifteen skilled ball catchers caught 160 balls with their preferred hand

  4. Primate Anatomy, Kinematics, and Principles for Humanoid Design

    Science.gov (United States)

    Ambrose, Robert O.; Ambrose, Catherine G.

    2004-01-01

    The primate order of animals is investigated for clues in the design of Humanoid Robots. The pursuit is directed with a theory that kinematics, musculature, perception, and cognition can be optimized for specific tasks by varying the proportions of limbs, and in particular, the points of branching in kinematic trees such as the primate skeleton. Called the Bifurcated Chain Hypothesis, the theory is that the branching proportions found in humans may be superior to other animals and primates for the tasks of dexterous manipulation and other human specialties. The primate taxa are defined, contemporary primate evolution hypotheses are critiqued, and variations within the order are noted. The kinematic branching points of the torso, limbs and fingers are studied for differences in proportions across the order, and associated with family and genus capabilities and behaviors. The human configuration of a long waist, long neck, and short arms is graded using a kinematic workspace analysis and a set of design axioms for mobile manipulation robots. It scores well. The re emergence of the human waist, seen in early Prosimians and Monkeys for arboreal balance, but lost in the terrestrial Pongidae, is postulated as benefiting human dexterity. The human combination of an articulated waist and neck will be shown to enable the use of smaller arms, achieving greater regions of workspace dexterity than the larger limbs of Gorillas and other Hominoidea.

  5. Relation between shoulder proprioception, kinematics and pain after stroke

    NARCIS (Netherlands)

    Niessen, M. H M; Veeger, H. E J; Meskers, C.G.; Koppe, P.A.; Konijnenbelt, M.H.; Janssen, T. W J

    2010-01-01

    Purpose: To identify a possible relationship between chronic Post-Stroke Shoulder Pain (PSSP), scapular resting pose and shoulder proprioception. Methods: A total of 21 inpatients with stroke and 10 healthy control subjects were included and kinematics and proprioception of both shoulders were

  6. Deceleration system for kinematic linkages of positioning

    Science.gov (United States)

    Stan, G.

    2017-08-01

    Flexible automation is used more and more in various production processes, so that both machining itself on CNC machine tools and workpiece handling means are performed through programming the needed working cycle. In order to obtain a successful precise positioning, each motion degree needs a certain deceleration before stopping at a programmed point. The increase of motion speed of moving elements within the manipulators structure depends directly on deceleration duty quality before the programmed stop. Proportional valves as well as servo-valves that can perform hydraulic decelerations are well known, but they feature several disadvantages, such as: high price, severe conditions for oil filtering and low reliability under industrial conditions. This work presents a new deceleration system that allows adjustment of deceleration slope according to actual conditions: inertial mass, speed etc. The new solution of hydraulic decelerator allows its integration to a position loop or its usage in case of positioning large elements that only perform fixed cycles. The results being obtained on the positioning accuracy of a linear axis using the new solution of the hydraulic decelerator are presented, too. The price of the new deceleration system is much lower compared to the price of proportional valves or servo-valves.

  7. Functional clinical typology of the foot and kinematic gait parameters

    Directory of Open Access Journals (Sweden)

    Jitka Marenčáková

    2016-06-01

    Full Text Available Background: The foot plays a key role in a standing posture, walking and running performance. Changes in its structure or function may alter upper segments of kinematic chain which can lead to formation of musculoskeletal disorders. Although functional clinical typology provides a complex view of foot kinesiology there is a lack of knowledge and evidence about influences of different foot types on human gait. Objective: The aim of the study was to analyse differences of kinematic gait parameters of lower extremity joints and pelvis between functional clinical foot types in healthy young men. Methods: Three-dimensional kinematic analysis by the Vicon Motion Capture MX System device in synchronization with 2 Kistler force platforms was used to obtain kinematic data from 18 healthy men (mean age 23.2 ± 1.9 years. The functional clinical foot type was clinically examined and sorted into 3 basic foot type groups - forefoot varus (FFvar, rearfoot varus (RFvar and forefoot valgus (FFvalg. Peak angular values and range of an angular displacement in all of three movement planes were analysed for pelvis, hip, knee and ankle joint. For statistical analysis of kinematic gait parameters differences between foot types Mann Whitney U test at a statistical significance level p < .05 and Cohen's coefficient d for effect size were used. Results: This study showed that functional clinical foot type can affect kinematic parameters of gait in the joints of the lower limb and pelvis. Significant differences were presented in the FFvar in comparison with other two foot type groups with middle and high size of effect. The most alterations were observed in pelvis area and in a sagittal plane of movement. Nevertheless, significant differences between FFvalg and RFvar foot types were not noticed. Conclusions: Functional clinical foot typology provides one of the possible methods to describe foot structure and function. Our results showed that foot type could

  8. Ex vivo kinematic studies of a canine unlinked semi-constrained hybrid total elbow arthroplasty system.

    Science.gov (United States)

    Lorenz, N D; Channon, S; Pettitt, R; Smirthwaite, P; Innes, J F

    2015-01-01

    Introduction of the Sirius® canine total elbow arthroplasty system, and presentation of the results of a passive range-of-motion analysis based on ex vivo kinematic studies pre-and post-implantation. Thoracic limbs (n = 4) of medium sized dogs were harvested by forequarter amputation. Plain orthogonal radiographs of each limb were obtained pre- and post-implantation. Limbs were prepared by placement of external fixator pins and Kirschner wires into the humerus and radius. Each limb was secured into a custom-made box frame and retro-reflective markers were placed on the exposed ends of the pins and wires. Each elbow was manually moved through five ranges-of-motion manoeuvres. Data collected included six trials of i) full extension to full flexion and ii) pronation and supination in 90° flexion; a three-dimensional motion capture system was used to collect and analyse the data. The Sirius elbow prosthesis was subsequently implanted and the same measurements were repeated. Data sets were tested for normality. Paired t-tests were used for comparison of pre- and post-implantation motion parameters. Kinematic analysis showed that the range-of-motion (mean and SD) for flexion and extension pre-implantation was 115° ± 6 (range: 25° to 140°). The range-of-motion in the sagittal plane post-implantation was 90° ± 4 (range: 36° to 130°) and this reduction was significant (p = 0.0001). The ranges-of-motion (mean and SD) for supination and pronation at 90° were 50° ± 5, whereas the corresponding mean ranges-of-motion post-implantation were 38° ± 6 (p = 0.0188). Compared to a normal elbow, the range-of-motion was reduced. Post-implantation, supination and pronation range-of-motion was significantly reduced at 90° over pre-implantation values. These results provide valuable information regarding the effect of the Sirius system on ex vivo kinematics of the normal canine elbow joint. Further, this particular ex vivo model allowed for satisfactory and repeatable

  9. 3-D subduction dynamics in the western Pacific: Mantle pressure, plate kinematics, and dynamic topography.

    Science.gov (United States)

    Holt, A. F.; Royden, L.; Becker, T. W.; Faccenna, C.

    2017-12-01

    While it is well established that the slab pull of negatively buoyant oceanic plates is the primary driving force of plate tectonics, the dynamic "details" of subduction have proved difficult to pin down. We use the Philippine Sea Plate region of the western Pacific as a site to explore links between kinematic observables (e.g. topography and plate motions) and the dynamics of the subduction system (e.g. mantle flow, mantle pressure). To first order, the Philippine Sea Plate can be considered to be the central plate of a double slab system containing two slabs that dip in the same direction, to the west. This subduction configuration presents the opportunity to explore subduction dynamics in a setting where two closely spaced slabs interact via subduction-induced mantle flow and stresses transmitted through the intervening plate. We use a 3-D numerical approach (e.g. Holt et al., 2017), augmented by semi-analytical models (e.g. Jagoutz et al., 2017), to develop relationships between dynamic processes and kinematic properties, including plate velocities, lithospheric stress state, slab dip angles, and topography. When combined with subduction zone observables, this allows us to isolate the first order dynamic processes that are in operation in the Philippine Sea Plate region. Our results suggest that positive pressure build-up occurs in the asthenosphere between the two slabs (Izu-Bonin-Mariana and Ryukyu-Nankai), and that this is responsible for producing much of the observed kinematic variability in the region, including the steep dip of the Pacific slab at the Izu-Bonin-Mariana trench, as compared to the flat dip of the Pacific slab north of Japan. We then extend our understanding of the role of asthenospheric pressure to examine the forces responsible for the plate kinematics and dynamic topography of the entire Western Pacific subduction margin(s). References:Holt, A. F., Royden, L. H., Becker, T. W., 2017. Geophys. J. Int., 209, 250-265Jagoutz, O., Royden, L

  10. Software Development for the Kinematic Analysis of a Lynx 6 Robot Arm

    OpenAIRE

    Baki Koyuncu; Mehmet Güzel

    2007-01-01

    The kinematics of manipulators is a central problem in the automatic control of robot manipulators. Theoretical background for the analysis of the 5 Dof Lynx-6 educational Robot Arm kinematics is presented in this paper. The kinematics problem is defined as the transformation from the Cartesian space to the joint space and vice versa. The Denavit-Harbenterg (D-H) model of representation is used to model robot links and joints in this study. Both forward and inverse kinematics solutions for th...

  11. Development of a parametric kinematic model of the human hand and a novel robotic exoskeleton.

    Science.gov (United States)

    Burton, T M W; Vaidyanathan, R; Burgess, S C; Turton, A J; Melhuish, C

    2011-01-01

    This paper reports the integration of a kinematic model of the human hand during cylindrical grasping, with specific focus on the accurate mapping of thumb movement during grasping motions, and a novel, multi-degree-of-freedom assistive exoskeleton mechanism based on this model. The model includes thumb maximum hyper-extension for grasping large objects (~> 50 mm). The exoskeleton includes a novel four-bar mechanism designed to reproduce natural thumb opposition and a novel synchro-motion pulley mechanism for coordinated finger motion. A computer aided design environment is used to allow the exoskeleton to be rapidly customized to the hand dimensions of a specific patient. Trials comparing the kinematic model to observed data of hand movement show the model to be capable of mapping thumb and finger joint flexion angles during grasping motions. Simulations show the exoskeleton to be capable of reproducing the complex motion of the thumb to oppose the fingers during cylindrical and pinch grip motions. © 2011 IEEE

  12. Uncertainty measurement with the kinematic telescopic bar during industrial robot inaccuracy tests

    Directory of Open Access Journals (Sweden)

    Józwik Jerzy

    2017-01-01

    Full Text Available Abstract. The subject of this article is the assessment of measurement uncertainty with the kinematic telescopic bar QC20-W in the accuracy test of MOTOMAN HP20 industrial robot. The measurements were performed to determine the statistical uncertainty of error measurement using the system applied. Analysed in tests was the robot’s ability to recreate a circular outline through standard, complex and extended measurement of uncertainty measurement. The obtained results were served to perform rapid evaluation of robot inaccuracy. These uncertainties were based on the information included in the device calibration certificate (estimated with method B but also on the basis of measurements and statistical data (estimated with method A. These components of the uncertainty budget take relatively small values (uc=0.818÷4.130; U=1.636÷8.260 for k=2, which proves that a properly selected method was applied to the research task. The method of research and calculation precisely identified key uncertainties allowing for an objective assessment of the industrial robot errors carried out with Renishaw the kinematic telescopic bar.

  13. Feeding Kinematics, Suction, and Hydraulic Jetting Performance of Harbor Seals (Phoca vitulina)

    Science.gov (United States)

    Marshall, Christopher D.; Wieskotten, Sven; Hanke, Wolf; Hanke, Frederike D.; Marsh, Alyssa; Kot, Brian; Dehnhardt, Guido

    2014-01-01

    The feeding kinematics, suction and hydraulic jetting capabilities of captive harbor seals (Phoca vitulina) were characterized during controlled feeding trials. Feeding trials were conducted using a feeding apparatus that allowed a choice between biting and suction, but also presented food that could be ingested only by suction. Subambient pressure exerted during suction feeding behaviors was directly measured using pressure transducers. The mean feeding cycle duration for suction-feeding events was significantly shorter (0.15±0.09 s; Pfeeding events (0.18±0.08 s). Subjects feeding in-water used both a suction and a biting feeding mode. Suction was the favored feeding mode (84% of all feeding events) compared to biting, but biting comprised 16% of feeding events. In addition, seals occasionally alternated suction with hydraulic jetting, or used hydraulic jetting independently, to remove fish from the apparatus. Suction and biting feeding modes were kinematically distinct regardless of feeding location (in-water vs. on-land). Suction was characterized by a significantly smaller gape (1.3±0.23 cm; Pfeeding events. Harbor seals displayed a wide repertoire of behaviorally flexible feeding strategies to ingest fish from the feeding apparatus. Such flexibility of feeding strategies and biomechanics likely forms the basis of their opportunistic, generalized feeding ecology and concomitant breadth of diet. PMID:24475170

  14. The kinematic preshaping of triggered self-adaptive linkage-driven robotic fingers

    Directory of Open Access Journals (Sweden)

    L. Birglen

    2011-02-01

    Full Text Available In this paper, the issue of the kinematic – as opposed to dynamic – preshaping of self-adaptive robotic fingers driven by linkages is discussed. A method to obtain designs of these fingers capable of various behaviours during their closing motions is presented. The method is based on using triggered passive elements in carefully selected joints of the finger and the selection or optimization of geometric parameters to obtain particular kinematic relationships between the motions of the phalanges. This method is very general and can be applied to any self-adaptive robotic finger in order to obtain many different types of closing motions. Examples given in this paper are focusing on two different preshaping motions, the first one aims at allowing pinch grasps while the second mimics a human finger. The fundamental aim of this paper is to show that various preshapings of self-adaptive fingers are possible, not just one, and to give two step-by-step examples.

    This paper was presented at the IFToMM/ASME International Workshop on Underactuated Grasping (UG2010, 19 August 2010, Montréal, Canada.

  15. Kinematical and dynamical aspects of higher-spin bound-state equations in holographic QCD

    Energy Technology Data Exchange (ETDEWEB)

    de Téramond, Guy F.; Dosch, Hans Günter; Brodsky, Stanley J.

    2013-04-01

    In this paper we derive holographic wave equations for hadrons with arbitrary spin starting from an effective action in a higher-dimensional space asymptotic to anti–de Sitter (AdS) space. Our procedure takes advantage of the local tangent frame, and it applies to all spins, including half-integer spins. An essential element is the mapping of the higher-dimensional equations of motion to the light-front Hamiltonian, thus allowing a clear distinction between the kinematical and dynamical aspects of the holographic approach to hadron physics. Accordingly, the nontrivial geometry of pure AdS space encodes the kinematics, and the additional deformations of AdS space encode the dynamics, including confinement. It thus becomes possible to identify the features of holographic QCD, which are independent of the specific mechanisms of conformal symmetry breaking. In particular, we account for some aspects of the striking similarities and differences observed in the systematics of the meson and baryon spectra.

  16. Quantifying the performance of jet definitions for kinematic reconstruction at the LHC

    International Nuclear Information System (INIS)

    Cacciari, Matteo; Rojo, Juan; Salam, Gavin P.; Soyez, Gregory

    2008-01-01

    We present a strategy to quantify the performance of jet definitions in kinematic reconstruction tasks. It is designed to make use exclusively of physical observables, in contrast to previous techniques which often used unphysical Monte Carlo partons as a reference. It is furthermore independent of the detailed shape of the kinematic distributions. We analyse the performance of 5 jet algorithms over a broad range of jet-radii, for sources of quark jets and gluon jets, spanning the energy scales of interest at the LHC, both with and without pileup. The results allow one to identify optimal jet definitions for the various scenarios. They confirm that the use of a small jet radius (R ≅ 0.5) for quark-induced jets at moderate energy scales, O(100 GeV), is a good choice. However, for gluon jets and in general for TeV scales, there are significant benefits to be had from using larger radii, up to R ∼> 1. This has implications for the span of jet-definitions that the LHC experiments should provide as defaults for searches and other physics analyses.

  17. Mechanical versus kinematical shortening reconstructions of the Zagros High Folded Zone (Kurdistan region of Iraq)

    Science.gov (United States)

    Frehner, Marcel; Reif, Daniel; Grasemann, Bernhard

    2012-06-01

    This paper compares kinematical and mechanical techniques for the palinspastic reconstruction of folded cross sections in collision orogens. The studied area and the reconstructed NE-SW trending, 55.5 km long cross section is located in the High Folded Zone of the Zagros fold-and-thrust belt in the Kurdistan region of Iraq. The present-day geometry of the cross section has been constructed from field as well as remote sensing data. In a first step, the structures and the stratigraphy are simplified and summarized in eight units trying to identify the main geometric and mechanical parameters. In a second step, the shortening is kinematically estimated using the dip domain method to 11%-15%. Then the same cross section is used in a numerical finite element model to perform dynamical unfolding simulations taking various rheological parameters into account. The main factor allowing for an efficient dynamic unfolding is the presence of interfacial slip conditions between the mechanically strong units. Other factors, such as Newtonian versus power law viscous rheology or the presence of a basement, affect the numerical simulations much less strongly. If interfacial slip is accounted for, fold amplitudes are reduced efficiently during the dynamical unfolding simulations, while welded layer interfaces lead to unrealistic shortening estimates. It is suggested that interfacial slip and decoupling of the deformation along detachment horizons is an important mechanical parameter that controlled the folding processes in the Zagros High Folded Zone.

  18. Online Kinematic and Dynamic-State Estimation for Constrained Multibody Systems Based on IMUs

    Directory of Open Access Journals (Sweden)

    José Luis Torres-Moreno

    2016-03-01

    Full Text Available This article addresses the problems of online estimations of kinematic and dynamic states of a mechanism from a sequence of noisy measurements. In particular, we focus on a planar four-bar linkage equipped with inertial measurement units (IMUs. Firstly, we describe how the position, velocity, and acceleration of all parts of the mechanism can be derived from IMU signals by means of multibody kinematics. Next, we propose the novel idea of integrating the generic multibody dynamic equations into two variants of Kalman filtering, i.e., the extended Kalman filter (EKF and the unscented Kalman filter (UKF, in a way that enables us to handle closed-loop, constrained mechanisms, whose state space variables are not independent and would normally prevent the direct use of such estimators. The proposal in this work is to apply those estimators over the manifolds of allowed positions and velocities, by means of estimating a subset of independent coordinates only. The proposed techniques are experimentally validated on a testbed equipped with encoders as a means of establishing the ground-truth. Estimators are run online in real-time, a feature not matched by any previous procedure of those reported in the literature on multibody dynamics.

  19. Smartphones as Integrated Kinematic and Dynamic Sensors for Amusement Park Physics Applications

    Science.gov (United States)

    Peterson, Stephanie; Dennison, J. R.

    2010-10-01

    USU has hosted Physics Day at Lagoon and has attracted more than 120,000 secondary educators and students over 21 years. During this educational day, students explore basic physics concepts and apply their classroom content outdoors, in real world applications. As part of the event, USU's Physics Department provides curriculum to be used at Lagoon, in similar outside venues, and in the classroom. One such educational instrument, which is a primary focus of this work, is student workbooks filled with activities ranging from very simple to more advanced topics. Workbooks cover the properties of waves, relative velocity, and acceleration, topics which have historically challenged students and future topics include kinematics, energy, and forces. The topics were selected based on requests from teachers throughout the Intermountain Region and identified deficiencies in student performance on core curriculum assessments. An innovative approach is to identify physical application of iPhone and Android smartphone software technologies, which make use of dynamic and kinematic sensors. These technologies will allow students to realize their ability to do quantitative physics calculations anywhere, anytime; a smart device which is highly salable to today's teenage learners. This also provides an exciting approach to more fully engage students in learning physics concepts.

  20. Automated Kinematics Equations Generation and Constrained Motion Planning Resolution for Modular and Reconfigurable Robots

    Energy Technology Data Exchange (ETDEWEB)

    Pin, Francois G.; Love, Lonnie L.; Jung, David L.

    2004-03-29

    Contrary to the repetitive tasks performed by industrial robots, the tasks in most DOE missions such as environmental restoration or Decontamination and Decommissioning (D&D) can be characterized as ''batches-of-one'', in which robots must be capable of adapting to changes in constraints, tools, environment, criteria and configuration. No commercially available robot control code is suitable for use with such widely varying conditions. In this talk we present our development of a ''generic code'' to allow real time (at loop rate) robot behavior adaptation to changes in task objectives, tools, number and type of constraints, modes of controls or kinematics configuration. We present the analytical framework underlying our approach and detail the design of its two major modules for the automatic generation of the kinematics equations when the robot configuration or tools change and for the motion planning under time-varying constraints. Sample problems illustrating the capabilities of the developed system are presented.

  1. The relationship between lumbar spine kinematics during gait and low-back pain in transfemoral amputees.

    Science.gov (United States)

    Morgenroth, David C; Orendurff, Michael S; Shakir, Ali; Segal, Ava; Shofer, Jane; Czerniecki, Joseph M

    2010-08-01

    Low-back pain is an important cause of secondary disability in transfemoral amputees. The primary aim of our study is to assess the differences in lumbar spine kinematics during gait between transfemoral amputees with and without low-back pain. Lumbar spine kinematics in three planes were measured when the subjects walked in a motion analysis laboratory. Nine transfemoral amputees with low-back pain, eight transfemoral amputees without low-back pain, and six healthy, nonamputee subjects participated. The Amputee Pain and Amputee No Pain groups were essentially the same in terms of all demographic and potentially confounding variable measures. Transfemoral amputees with low-back pain showed greater transverse plane rotational excursion in their lumbar spine during walking when compared with transfemoral amputees without low-back pain (P = 0.029; effect size = 1.03). There were no significant differences in sagittal or coronal plane lumbar spine excursions during walking between these two groups. Although our study design does not allow for proving causation, increased transverse plane rotation has been associated with intervertebral disc degeneration, suggesting that increased transverse plane rotation secondary to walking with a prosthetic limb may be a causative factor in the etiology of low-back pain in transfemoral amputees. Identifying differences in lumbar motion can lead to potential preventative and therapeutic intervention strategies.

  2. The kinematics of the California sea lion foreflipper during forward swimming

    International Nuclear Information System (INIS)

    Friedman, C; Leftwich, M C

    2014-01-01

    To determine the two-dimensional kinematics of the California sea lion foreflipper during thrust generation, a digital, high-definition video is obtained using a non-research female sea lion at the Smithsonian National Zoological Park in Washington, DC. The observational videos are used to extract maneuvers of interest—forward acceleration from rest using the foreflippers and banked turns. Single camera videos are analyzed to digitize the flipper during the motions using 10 points spanning root to tip in each frame. Digitized shapes were then fitted with an empirical function that quantitatively allows for both comparison between different claps, and for extracting kinematic data. The resulting function shows a high degree of curvature (with a camber of up to 32%). Analysis of sea lion acceleration from rest shows thrust production in the range of 150–680 N and maximum flipper angular velocity (for rotation about the shoulder joint) as high as 20 rad s −1 . Analysis of turning maneuvers indicate extreme agility and precision of movement driven by the foreflipper surfaces. (paper)

  3. Simulation, experimental validation and kinematic optimization of a Stirling engine using air and helium

    International Nuclear Information System (INIS)

    Bert, Juliette; Chrenko, Daniela; Sophy, Tonino; Le Moyne, Luis; Sirot, Frédéric

    2014-01-01

    A Stirling engine with nominal output power of 1 kW is tested using air and helium as working gases. The influence of working pressure, engine speed and temperature of the hot source is studied, analyzing instantaneous gas pressure as well as instantaneous and stationary temperature at different positions to derive the effective power. A zero dimensional finite-time thermodynamic, three zones model of a generic Stirling engine is developed and successfully validated against experimental gas temperature and pressure in each zone, providing the effective power. This validation underlines the interest of different working gases as well as different geometric configurations for different applications. Furthermore, the validated model allows parametric studies of the engine, with regard to geometry, working gas and engine kinematics. It is used in order to optimize the kinematic of a Stirling engine for different working points and gases. - Highlights: • A Stirling engine of 1 kW is tested using air and helium as working gas. • Effects of working pressure, speed and temperature on power are studied. • A zero dimensional finite-time thermodynamic, three zones model of it is validated. • The validated model is used for parametric studies and optimization of the engine

  4. Does Confucianism allow for body donation?

    Science.gov (United States)

    Jones, D Gareth; Nie, Jing-Bao

    2018-01-16

    Confucianism has been widely perceived as a major moral and cultural obstacle to the donation of bodies for anatomical purposes. The rationale for this is the Confucian stress on xiao (filial piety), whereby individuals' bodies are to be intact at death. In the view of many, the result is a prohibition on the donation of bodies to anatomy departments for the purpose of dissection. The role of dissection throughout the development of anatomy within a Confucian context is traced, and in contemporary China the establishment of donation programs and the appearance of memorial monuments is noted. In reassessing Confucian attitudes, the stress laid on a particular interpretation of filial piety is questioned, and an attempt is made to balance this with the Confucian emphasis on a moral duty to those outside one's immediate family. The authors argue that the fundamental Confucian norm ren (humaneness or benevolence) allows for body donation as people have a moral duty to help others. Moreover, the other central Confucian value, li (rites), offers important insights on how body donation should be performed as a communal activity, particularly the necessity of developing ethically and culturally appropriate rituals for body donation. In seeking to learn from this from a Western perspective, it is contended that in all societies the voluntary donation of bodies is a deeply human activity that is to reflect the characteristics of the community within which it takes place. This is in large part because it has educational and personal repercussions for students. Anat Sci Educ. © 2018 American Association of Anatomists. © 2018 American Association of Anatomists.

  5. Upper-limb kinematic reconstruction during stroke robot-aided therapy.

    Science.gov (United States)

    Papaleo, E; Zollo, L; Garcia-Aracil, N; Badesa, F J; Morales, R; Mazzoleni, S; Sterzi, S; Guglielmelli, E

    2015-09-01

    The paper proposes a novel method for an accurate and unobtrusive reconstruction of the upper-limb kinematics of stroke patients during robot-aided rehabilitation tasks with end-effector machines. The method is based on a robust analytic procedure for inverse kinematics that simply uses, in addition to hand pose data provided by the robot, upper arm acceleration measurements for computing a constraint on elbow position; it is exploited for task space augmentation. The proposed method can enable in-depth comprehension of planning strategy of stroke patients in the joint space and, consequently, allow developing therapies tailored for their residual motor capabilities. The experimental validation has a twofold purpose: (1) a comparative analysis with an optoelectronic motion capturing system is used to assess the method capability to reconstruct joint motion; (2) the application of the method to healthy and stroke subjects during circle-drawing tasks with InMotion2 robot is used to evaluate its efficacy in discriminating stroke from healthy behavior. The experimental results have shown that arm angles are reconstructed with a RMSE of 8.3 × 10(-3) rad. Moreover, the comparison between healthy and stroke subjects has revealed different features in the joint space in terms of mean values and standard deviations, which also allow assessing inter- and intra-subject variability. The findings of this study contribute to the investigation of motor performance in the joint space and Cartesian space of stroke patients undergoing robot-aided therapy, thus allowing: (1) evaluating the outcomes of the therapeutic approach, (2) re-planning the robotic treatment based on patient needs, and (3) understanding pathology-related motor strategies.

  6. Effects of Dynamical Evolution on Globular Clusters’ Internal Kinematics

    Science.gov (United States)

    Tiongco, Maria; Vesperini, Enrico; Varri, Anna Lisa

    2018-01-01

    The synergy between recent photometric, spectroscopic, and astrometric studies is revealing that globular clusters deviate from the traditional picture of dynamically simple and single stellar population systems. Complex kinematical features such as velocity anisotropy and rotation, and the existence of multiple stellar populations are some of the key observational findings. My thesis work has aimed to build a theoretical framework to interpret these new observational results and to understand their link with a globular cluster’s dynamical history.I have focused on the study of the evolution of globular clusters' internal kinematics, as driven by two-body relaxation, and the interplay between internal angular momentum and the external Galactic tidal field. With a specifically-designed, large survey of direct N-body simulations, I have explored the three-dimensional structure of the velocity space of tidally-perturbed clusters, by characterizing their degree of anisotropy and their rotational properties. These studies have proved that a cluster's kinematical properties contain a distinct imprints of the cluster’s initial structural properties, dynamical history, and tidal environment. By relaxing a number of simplifying assumptions that are traditionally imposed, I have also showed how the interplay between a cluster's internal evolution and the interaction with the host galaxy can produce complex morphological and kinematical properties, such as a counter-rotating core and a twisting of the projected isodensity contours.Building on this fundamental understanding, I have then studied the dynamics of multiple stellar populations in globular clusters, with attention to the largely unexplored role of angular momentum. I have analyzed the evolution of clusters with stellar populations characterized by different initial structural and kinematical properties to determine how long these differences are preserved, and in what cases they could still be observable in

  7. STRUCTURAL IDENTIFICATION OF DISTINCT INVERSIONS OF PLANAR KINEMATIC CHAINS

    Directory of Open Access Journals (Sweden)

    Dr. Shubhashis Sanyal

    2011-12-01

    Full Text Available 0 0 1 171 979 International Islamic University 8 2 1148 14.0 Normal 0 false false false EN-US JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Times New Roman";} Inversions are various structural possibilities of a kinematic chain. The number of inversions depends on the number of links of a kinematic chain. At the stage of structural synthesis, identification of distinct structural inversions of a particular type of kinematic chain is necessary. Various researchers have proposed methods for identification of distinct inversions. Present method based on Link joint connectivity is proposed to identify the distinct inversions of a planar kinematic chain. Method is tested successfully on single degree and multiple degree of freedom planar kinematic chains. ABSTRAK: Penyonsangan merupakan kebarangkalian pelbagai struktur suatu rangkaian kinematik. Jumlah songsangan bergantung kepada jumlah hubungan suatu rangkaian kinematik. Pada peringkat sintesis struktur, pengenalan songsangan struktur yang berbeza untuk suatu jenis rangkaian kinematik adalah perlu. Ramai penyelidik telah mencadangkan pelbagai kaedah pengenalan songsangan yang berbeza. Kaedah terkini berdasarkan hubungan kesambungan bersama telah dicadangkan untuk mengenalpasti songsangan yang berbeza dalam suatu satah rangkaian kinematik.

  8. Circular arc snakes and kinematic surface generation

    KAUST Repository

    Barton, Michael

    2013-05-01

    We discuss the theory, discretization, and numerics of curves which are evolving such that part of their shape, or at least their curvature as a function of arc length, remains unchanged. The discretization of a curve as a smooth sequence of circular arcs is well suited for such purposes, and allows us to reduce evolution of curves to the evolution of a control point collection in a certain finite-dimensional shape space. We approach this evolution by a 2-step process: linearized evolution via optimized velocity fields, followed by optimization in order to exactly fulfill all geometric side conditions. We give applications to freeform architecture, including "rationalization" of a surface by congruent arcs, form finding and, most interestingly, non-static architecture. © 2013 The Author(s) Computer Graphics Forum © 2013 The Eurographics Association and Blackwell Publishing Ltd.

  9. Wheel skid correction is a prerequisite to reliably measure wheelchair sports kinematics based on inertial sensors

    NARCIS (Netherlands)

    Van der Slikke, R.M.A.; Berger, M.A.M.; Bregman, D.J.J.; Veeger, H.E.J.

    2015-01-01

    Accurate knowledge of wheelchair kinematics during a match could be a significant factor in performance improvement in wheelchair basketball. To date, most systems for measuring wheelchair kinematics are not suitable for match applications or lack detail in key kinematic outcomes. This study

  10. Towards a naturalistic brain-machine interface: hybrid torque and position control allows generalization to novel dynamics.

    Directory of Open Access Journals (Sweden)

    Pratik Y Chhatbar

    Full Text Available Realization of reaching and grasping movements by a paralytic person or an amputee would greatly facilitate her/his activities of daily living. Towards this goal, control of a computer cursor or robotic arm using neural signals has been demonstrated in rodents, non-human primates and humans. This technology is commonly referred to as a Brain-Machine Interface (BMI and is achieved by predictions of kinematic parameters, e.g. position or velocity. However, execution of natural movements, such as swinging baseball bats of different weights at the same speed, requires advanced planning for necessary context-specific forces in addition to kinematic control. Here we show, for the first time, the control of a virtual arm with representative inertial parameters using real-time neural control of torques in non-human primates (M. radiata. We found that neural control of torques leads to ballistic, possibly more naturalistic movements than position control alone, and that adding the influence of position in a hybrid torque-position control changes the feedforward behavior of these BMI movements. In addition, this level of control was achievable utilizing the neural recordings from either contralateral or ipsilateral M1. We also observed changed behavior of hybrid torque-position control under novel external dynamic environments that was comparable to natural movements. Our results demonstrate that inclusion of torque control to drive a neuroprosthetic device gives the user a more direct handle on the movement execution, especially when dealing with novel or changing dynamic environments. We anticipate our results to be a starting point of more sophisticated algorithms for sensorimotor neuroprostheses, eliminating the need of fully automatic kinematic-to-dynamic transformations as currently used by traditional kinematic-based decoders. Thus, we propose that direct control of torques, or other force related variables, should allow for more natural

  11. Parametric Method to Define Area of Allowable Configurations while Changing Position of Restricted Zones

    Science.gov (United States)

    Pritykin, F. N.; Nefedov, D. I.; Rogoza, Yu A.; Zinchenko, Yu V.

    2018-03-01

    The article presents the findings related to the development of the module for automatic collision detection of the manipulator with restricted zones for virtual motion modeling. It proposes the parametric method for specifying the area of allowable joint configurations. The authors study the cases when restricted zones are specified using the horizontal plane or front-projection planes. The joint coordinate space is specified by rectangular axes in the direction of which the angles defining the displacements in turning pairs are laid off. The authors present the results of modeling which enabled to develop a parametric method for specifying a set of cross-sections defining the shape and position of allowable configurations in different positions of a restricted zone. All joint points that define allowable configurations refer to the indicated sections. The area of allowable configurations is specified analytically by using several kinematic surfaces that limit it. A geometric analysis is developed based on the use of the area of allowable configurations characterizing the position of the manipulator and reported restricted zones. The paper presents numerical calculations related to virtual simulation of the manipulator path performed by the mobile robot Varan when using the developed algorithm and restricted zones. The obtained analytical dependencies allow us to define the area of allowable configurations, which is a knowledge pool to ensure the intelligent control of the manipulator path in a predefined environment. The use of the obtained region to synthesize a joint trajectory makes it possible to correct the manipulator path to foresee and eliminate deadlocks when synthesizing motions along the velocity vector.

  12. Kinematics and trajectory synthesis of manipulation robots

    CERN Document Server

    Vukobratović, Miomir

    1986-01-01

    A few words about the series "Scientific Fundamentals of Robotics" should be said on the occasion of publication of the present monograph. This six-volume series has been conceived so as to allow the readers to master a contemporary approach to the construction and synthesis of con­ trol for manipulation ~obots. The authors' idea was to show how to use correct mathematical models of the dynamics of active spatial mecha­ nisms for dynamic analysis of robotic systems, optimal design of their mechanical parts based on the accepted criteria and imposed constraints, optimal choice of actuators, synthesis of dynamic control algorithms and their microcomputer implementation. In authors' oppinion this idea has been relatively successfully realized within the six-volume mono­ graphic series. Let us remind the readers of the books of this series. Volumes 1 and 2 are devoted to the dynamics and control algorithms of manipulation ro­ bots, respectively. They form the first part of the series which has a certain topic...

  13. Autonomous Kinematic Calibration of the Robot Manipulator with a Linear Laser-Vision Sensor

    Science.gov (United States)

    Kang, Hee-Jun; Jeong, Jeong-Woo; Shin, Sung-Weon; Suh, Young-Soo; Ro, Young-Schick

    This paper presents a new autonomous kinematic calibration technique by using a laser-vision sensor called "Perceptron TriCam Contour". Because the sensor measures by capturing the image of a projected laser line on the surface of the object, we set up a long, straight line of a very fine string inside the robot workspace, and then allow the sensor mounted on a robot to measure the point intersection of the line of string and the projected laser line. The data collected by changing robot configuration and measuring the intersection points are constrained to on a single straght line such that the closed-loop calibration method can be applied. The obtained calibration method is simple and accurate and also suitable for on-site calibration in an industrial environment. The method is implemented using Hyundai VORG-35 for its effectiveness.

  14. OPTIMASS: A Package for the Minimization of Kinematic Mass Functions with Constraints

    CERN Document Server

    Cho, Won Sang; Kim, Doojin; Lim, Sung Hak; Matchev, Konstantin T.; Moortgat, Filip; Pape, Luc; Park, Myeonghun

    2016-01-01

    Reconstructed mass variables, such as $M_2$, $M_{2C}$, $M_T^\\star$, and $M_{T2}^W$, play an essential role in searches for new physics at hadron colliders. The calculation of these variables generally involves constrained minimization in a large parameter space, which is numerically challenging. We provide a C++ code, OPTIMASS, which interfaces with the MINUIT library to perform this constrained minimization using the Augmented Lagrangian Method. The code can be applied to arbitrarily general event topologies and thus allows the user to significantly extend the existing set of kinematic variables. We describe this code and its motivation and demonstrate its use in the analysis of the fully leptonic decay of pair-produced top quarks using the $M_2$ variables.

  15. Kinematical analysis with the Emulsion Cloud Chamber in the OPERA experiment

    CERN Document Server

    Di Capua, F

    2010-01-01

    The OPERA experiment aims at measuring for the first time neutrino oscil- lation in appearance mode through the detection of ni-tau in an almost pure niμ beam produced at CERN SPS (CNGS), 730 km far from the detector. The ni-tau appearance signal is identified through the measurement of the decay daughter particles of the " lepton produced in CC ni-tau interactions. Since the short-lived " particle has, at the energy of the beam, an average decay length shorter than a 1 mm, a micrometric detection resolution is needed. The OPERA appara- tus is hybrid, using nuclear emulsion as high precision tracker and electronic detectors for the time stamp, event localization in the target and muon recon- struction. The Emulsion Cloud Chamber technique fulfils the requirement of a microscopic resolution together with a large target mass. The kinematical analysis allowed by this technique is described.

  16. Performance improvement for GPS single frequency kinematic relative positioning under poor satellite visibility.

    Science.gov (United States)

    Chen, Wantong

    2016-01-01

    Reliable ambiguity resolution in difficult environments such as during setting/rising events of satellites or during limited satellite visibility is a significant challenge for GPS single frequency kinematic relative positioning. Here, a recursive estimation method combining both code and carrier phase measurements was developed that can tolerate recurrent satellite setting/rising and accelerate initialization in motion. We propose an ambiguity dimension expansion method by utilizing the partial ambiguity relevance of previous and current observations. In essence, this method attempts to integrate all useful information into the recursive estimation equation and performs a better least squares adjustment. Using this method, the success rate of the extended ambiguity estimation is independent of the satellite setting and shows robust performance despite poor satellite visibility. Our model allows integration of other useful information into the recursive process. Actual experiments in urban environments demonstrate that the proposed algorithm can improve the reliability and availability of relative positioning.

  17. Behaviour and kinematics of continuous ram filtration in bowhead whales (Balaena mysticetus)

    DEFF Research Database (Denmark)

    Simon, Malene Juul; Johnson, Mark; Madsen, Peter Teglberg

    2009-01-01

    rate of approximately 3 m3 s-1, amounting to some 2000 tonnes of water and prey filtered per dive. We conclude that a food niche of dense, slow-moving zooplankton prey has led balaenids to evolve locomotor and filtering systems adapted to work against a high drag at swimming speeds of less than 0......, or they must swim at slow speeds while filtering to reduce drag and oxygen consumption. Using digital tags with three-axis accelerometers, we studied bowhead whales feeding off West Greenland and present here, to our knowledge, the first detailed data on the kinematics and swimming behaviour of a balaenid...... whale filter feeding at depth. Bowhead whales employ a continuous fluking gait throughout the bottom phase of foraging dives, moving at very slow speeds (less than 1 m s-1), allowing them to filter feed continuously at depth. Despite the slow speeds, the large mouth aperture provides a water filtration...

  18. Studying the Kinematic Behavior of Coronal Mass Ejections and Other Solar Phenomena using the Time-Convolution Mapping Method

    Science.gov (United States)

    Hess Webber, Shea A.; Thompson, Barbara J.; Kwon, Ryun Young; Ireland, Jack

    2018-01-01

    An improved understanding of the kinematic properties of CMEs and CME-associated phenomena has several impacts: 1) a less ambiguous method of mapping propagating structures into their inner coronal manifestations, 2) a clearer view of the relationship between the “main” CME and CME-associated brightenings, and 3) an improved identification of the heliospheric sources of shocks, Type II bursts, and SEPs. We present the results of a mapping technique that facilitates the separation of CMEs and CME-associated brightenings (such as shocks) from background corona. The Time Convolution Mapping Method (TCMM) segments coronagraph data to identify the time history of coronal evolution, the advantage being that the spatiotemporal evolution profiles allow users to separate features with different propagation characteristics. For example, separating “main” CME mass from CME-associated brightenings or shocks is a well-known obstacle, which the TCMM aids in differentiating. A TCMM CME map is made by first recording the maximum value each individual pixel in the image reaches during the traversal of the CME. Then the maximum value is convolved with an index to indicate the time that the pixel reached that value. The TCMM user is then able to identify continuous “kinematic profiles,” indicating related kinematic behavior, and also identify breaks in the profiles that indicate a discontinuity in kinematic history (i.e. different structures or different propagation characteristics). The maps obtained from multiple spacecraft viewpoints (i.e., STEREO and SOHO) can then be fit with advanced structural models to obtain the 3D properties of the evolving phenomena. We will also comment on the TCMM's further applicability toward the tracking of prominences, coronal hole boundaries and coronal cavities.

  19. Act on Numbers: Numerical Magnitude Influences Selection and Kinematics of Finger Movement

    Directory of Open Access Journals (Sweden)

    Rosa Rugani

    2017-08-01

    Full Text Available In the past decade hand kinematics has been reliably adopted for investigating cognitive processes and disentangling debated topics. One of the most controversial issues in numerical cognition literature regards the origin – cultural vs. genetically driven – of the mental number line (MNL, oriented from left (small numbers to right (large numbers. To date, the majority of studies have investigated this effect by means of response times, whereas studies considering more culturally unbiased measures such as kinematic parameters are rare. Here, we present a new paradigm that combines a “free response” task with the kinematic analysis of movement. Participants were seated in front of two little soccer goals placed on a table, one on the left and one on the right side. They were presented with left- or right-directed arrows and they were instructed to kick a small ball with their right index toward the goal indicated by the arrow. In a few test trials participants were presented also with a small (2 or a large (8 number, and they were allowed to choose the kicking direction. Participants performed more left responses with the small number and more right responses with the large number. The whole kicking movement was segmented in two temporal phases in order to make a hand kinematics’ fine-grained analysis. The Kick Preparation and Kick Finalization phases were selected on the basis of peak trajectory deviation from the virtual midline between the two goals. Results show an effect of both small and large numbers on action execution timing. Participants were faster to finalize the action when responding to small numbers toward the left and to large number toward the right. Here, we provide the first experimental demonstration which highlights how numerical processing affects action execution in a new and not-overlearned context. The employment of this innovative and unbiased paradigm will permit to disentangle the role of nature and culture

  20. Kinematic modeling of mobile robot with rocker-bogie link structure

    Science.gov (United States)

    Gang, Taig-Gi; Yi, Soo-Yeong

    2005-12-01

    A method for kinematic modeling of a mobile robot with rocker-bogie link mechanism was described. By using the well-known concept of the instantaneous coordinates, it derives the kinematic model for the full six degree of freedom motion including the x, y, and z motions and the pitch, roll, and yaw rotations. The kinematic model here implies both of the forward and the inverse kinematic equations. The forward kinematic equation with the wheel Jacobian matrices can be used to obtain the robot position and orientation from the measured wheel velocities and the rocker-bogie joint angles. On the contrary, the inverse kinematic equation implies a resulting robot motions consisting of body velocity and turning rate from the individual wheel velocities. Through the computer simulation, the kinematic model of the mobile robot was verified.

  1. Kinematics and Kinetics of Youth Baseball Catchers and Pitchers

    Directory of Open Access Journals (Sweden)

    Gretchen Oliver

    2015-09-01

    Full Text Available The purpose of this study was to compare the throwing kinematics and kinetics of youth catchers and pitchers. It was hypothesized that catchers and pitchers would exhibit differences throughout the throwing motion. Descriptive statistics were used to investigate kinematics during the four events of throwing: foot contact (FC, maximum shoulder external rotation (MER, ball release (BR and maximum shoulder internal rotation (MIR. Additionally, kinetics were investigated within phases of the events: Phase 1 (cocking; FC to MER, Phase 2 (acceleration; MER to BR and Phase 3 (deceleration; BR to MIR. Results revealed significant difference in torso flexion, lateral flexion, pelvis lateral flexion and segment velocities between the catchers and pitchers. Based on data from the current study, it appears that the youth catchers execute their throw as they have been instructed. It is unclear if the throwing mechanics displayed by these youth are efficient for a catcher, thus further investigation is needed to determine long-term injury susceptibility.

  2. Effect of environmental pH on sperm kinematic characteristics

    DEFF Research Database (Denmark)

    Alipour, Hiva; Dardmeh, Fereshteh; Dissing, Marianne Charlotte

    2015-01-01

    Semen preparation medium have an important role in assisted reproduction techniques and their composition influences sperm binding and motility. Some studies have assessed the influence of pH on sperm kinetics. However, no study to date has assessed the effect of environmental pH on subtle...... differences in the details of the sperm movement (kinematics) of human sperm provided by computerized sperm analysis systems. This study was designed to assess the effect of two different media pH levels on kinematic parameters of the human sperm. Samples were prepared using the 40%/80% Pureception (Sage, USA....... Linearity and Wobble showed significant difference after 24 hours. This study demonstrated a difference in the sperm motion pattern and velocity in different environmental pH levels. Based on these findings, further investigations are required to elucidate knowledge about possible effect of marginal p...

  3. D2 Delta Robot Structural Design and Kinematics Analysis

    Science.gov (United States)

    Yang, Xudong; wang, Song; Dong, Yu; Yang, Hai

    2017-12-01

    In this paper, a new type of Delta robot with only two degrees of freedom is proposed on the basis of multi - degree - of - freedom delta robot. In order to meet our application requirements, we have carried out structural design and analysis of the robot. Through SolidWorks modeling, combined with 3D printing technology to determine the final robot structure. In order to achieve the precise control of the robot, the kinematics analysis of the robot was carried out. The SimMechanics toolbox of MATLAB is used to establish the mechanism model, and the kinematics mathematical model is used to simulate the robot motion control in Matlab environment. Finally, according to the design mechanism, the working space of the robot is drawn by the graphic method, which lays the foundation for the motion control of the subsequent robot.

  4. Radiative distortion of kinematic edges in cascade decays

    Directory of Open Access Journals (Sweden)

    M. Beneke

    2017-07-01

    Full Text Available Kinematic edges of cascade decays of new particles produced in high-energy collisions may provide important constraints on the involved particles' masses. For the exemplary case of gluino decay g˜→qq¯χ˜ into a pair of quarks and a neutralino through a squark resonance, we study the hadronic invariant mass distribution in the vicinity of the kinematic edge. We perform a next-to-leading order calculation in the strong coupling αs and the ratio of squark width and squark mass Γq˜/mq˜, based on a systematic expansion in Γq˜/mq˜. The separation into hard, collinear and soft contributions elucidates the process-dependent and universal features of distributions in the edge region, represented by on-shell decay matrix elements, universal jet functions and a soft function that depends on the resonance propagator and soft Wilson lines.

  5. A novel mechanism for emulating insect wing kinematics

    International Nuclear Information System (INIS)

    Seshadri, Pranay; Benedict, Moble; Chopra, Inderjit

    2012-01-01

    A novel dual-differential four-bar flapping mechanism that can accurately emulate insect wing kinematics in all three degrees of freedom (translation, rotation and stroke plane deviation) is developed. The mechanism is specifically designed to be simple and scalable such that it can be utilized on an insect-based flapping wing micro air vehicle. Kinematic formulations for the wing stroke position, pitch angle and coning angle for this model are derived from first principles and compared with a 3D simulation. A benchtop flapping mechanism based on this model was designed and built, which was also equipped with a balance for force measurements. 3D motion capture tests were conducted on this setup to demonstrate the capability of generating complex figure-of-eight flapping motions along with dynamic pitching. The dual-differential four-bar mechanism was implemented on a light-weight vehicle that demonstrated tethered hover. (paper)

  6. Kinematical Compatibility Conditions for Vorticity Across Shock Waves

    Science.gov (United States)

    Baty, Roy

    2015-11-01

    This work develops the general kinematical compatibility conditions for vorticity across arbitrary shock waves in compressible, inviscid fluids. The vorticity compatibility conditions are derived from the curl of the momentum equation using singular distributions defined on two-dimensional shock wave surfaces embedded in three-dimensional flow fields. The singular distributions are represented as generalized differential operators concentrated on moving shock wave surfaces. The derivation of the compatibility conditions for vorticity requires the application of second-order generalized derivatives and elementary tensor algebra. The well-known vorticity jump conditions across a shock wave are then shown to follow from the general kinematical compatibility conditions for vorticity by expressing the flow field velocity in vectorial components normal and tangential to a shock surface.

  7. A kinematic model for Bayesian tracking of cyclic human motion

    Science.gov (United States)

    Greif, Thomas; Lienhart, Rainer

    2010-01-01

    We introduce a two-dimensional kinematic model for cyclic motions of humans, which is suitable for the use as temporal prior in any Bayesian tracking framework. This human motion model is solely based on simple kinematic properties: the joint accelerations. Distributions of joint accelerations subject to the cycle progress are learned from training data. We present results obtained by applying the introduced model to the cyclic motion of backstroke swimming in a Kalman filter framework that represents the posterior distribution by a Gaussian. We experimentally evaluate the sensitivity of the motion model with respect to the frequency and noise level of assumed appearance-based pose measurements by simulating various fidelities of the pose measurements using ground truth data.

  8. A School Experiment in Kinematics: Shooting from a Ballistic Cart

    Science.gov (United States)

    Kranjc, T.; Razpet, N.

    2011-10-01

    Many physics textbooks start with kinematics. In the lab, students observe the motions, describe and make predictions, and get acquainted with basic kinematics quantities and their meaning. Then they can perform calculations and compare the results with experimental findings. In this paper we describe an experiment that is not often done, but is interesting and attractive to students—the ballistic cart, i.e., the shooting of a ball from a cart moving along a slope. For that, one has to be familiar with one-dimensional uniform motion and one-dimensional motion with constant acceleration, as well as curvilinear motion that is a combination of such motions.1,2 The experimental results confirm theoretical predictions.

  9. A Model of Parallel Kinematics for Machine Calibration

    DEFF Research Database (Denmark)

    Pedersen, David Bue; Bæk Nielsen, Morten; Kløve Christensen, Simon

    2016-01-01

    . This research identifies that the rapid lift and repositioning capabilities of delta robots can reduce defects on extruded 3D printed parts when compared to traditional Cartesian motion systems. This is largely due to the fact that repositioning is so rapid that the extruded strand is instantly broken......Parallel kinematics have been adopted by more than 25 manufacturers of high-end desktop 3D printers [Wohlers Report (2015), p.118] as well as by research projects such as the WASP project [WASP (2015)], a 12 meter tall linear delta robot for Additive Manufacture of large-scale components...... the operator with a strong tool for easing this task. The kinematics and calibration of delta robots, in particular, are less researched than that of traditional Cartesian robots, for which tried-and-true methods for calibrating are well known. A forwards and reverse virtual model of a delta robot has been...

  10. On use of radial evanescence remain term in kinematic hardening

    International Nuclear Information System (INIS)

    Geyer, P.

    1995-01-01

    This paper presents the interest which lies in non-linear kinematic hardening rule with radial evanescence remain term as proposed for modelling multiaxial ratchetting. From analytical calculations in the case of the tension/torsion test, this ratchetting is compared with that proposed by Armstrong and Frederick. A modification is then proposed for Chaboche's elastoplastic model with two non-linear kinematic variables, by coupling the two types of hardening by means of two scalar parameters. Identification of these two parameters returns to speculate on the directions of strain in order to adjust the ratchetting to experimental observations. Using biaxial ratchetting tests on stainless steel 316 L specimens at ambient temperature, it is shown that satisfactory modelling of multiaxial ratchetting is obtained. (author). 4 refs., 5 figs

  11. [Advances on biomechanics and kinematics of sprain of ankle joint].

    Science.gov (United States)

    Zhao, Yong; Wang, Gang

    2015-04-01

    Ankle sprains are orthopedic clinical common disease, accounting for joint ligament sprain of the first place. If treatment is not timely or appropriate, the joint pain and instability maybe develop, and even bone arthritis maybe develop. The mechanism of injury of ankle joint, anatomical basis has been fully study at present, and the diagnostic problem is very clear. Along with the development of science and technology, biological modeling and three-dimensional finite element, three-dimensional motion capture system,digital technology study, electromyographic signal study were used for the basic research of sprain of ankle. Biomechanical and kinematic study of ankle sprain has received adequate attention, combined with the mechanism research of ankle sprain,and to explore the the biomechanics and kinematics research progress of the sprain of ankle joint.

  12. Kinematic analysis of a televised medial ankle sprain

    Directory of Open Access Journals (Sweden)

    Francesca E. Wade

    2018-04-01

    Full Text Available Ankle sprains are one of the most prevalent athletic injuries. Prior work has investigated lateral ankle sprains, but research on generally more severe medial sprains is lacking. This case report performs a kinematic analysis using novel motion analysis methods on a non-contact medial ankle sprain. Peak eversion (50° occurred 0.2 seconds following ground contact, maximum velocity of 426°/s, while peak dorsiflexion (64° occurred with a greater maximum velocity (573°/s. The combination of dorsiflexion at ground contact and rapid eversion is associated with a non-contact eversion sprain. This study provides a quantitative analysis of the eversion ankle sprain injury mechanism. Keywords: Athletic injury, Biomechanics, Ankle injury, Kinematics

  13. VRACK: measuring pedal kinematics during stationary bike cycling.

    Science.gov (United States)

    Farjadian, Amir B; Kong, Qingchao; Gade, Venkata K; Deutsch, Judith E; Mavroidis, Constantinos

    2013-06-01

    Ankle impairment and lower limb asymmetries in strength and coordination are common symptoms for individuals with selected musculoskeletal and neurological impairments. The virtual reality augmented cycling kit (VRACK) was designed as a compact mechatronics system for lower limb and mobility rehabilitation. The system measures interaction forces and cardiac activity during cycling in a virtual environment. The kinematics measurement was added to the system. Due to the constrained problem definition, the combination of inertial measurement unit (IMU) and Kalman filtering was recruited to compute the optimal pedal angular displacement during dynamic cycling exercise. Using a novel benchmarking method the accuracy of IMU-based kinematics measurement was evaluated. Relatively accurate angular measurements were achieved. The enhanced VRACK system can serve as a rehabilitation device to monitor biomechanical and physiological variables during cycling on a stationary bike.

  14. Visualized kinematics code for two-body nuclear reactions

    Science.gov (United States)

    Lee, E. J.; Chae, K. Y.

    2016-05-01

    The one or few nucleon transfer reaction has been a great tool for investigating the single-particle properties of a nucleus. Both stable and exotic beams are utilized to study transfer reactions in normal and inverse kinematics, respectively. Because many energy levels of the heavy recoil from the two-body nuclear reaction can be populated by using a single beam energy, identifying each populated state, which is not often trivial owing to high level-density of the nucleus, is essential. For identification of the energy levels, a visualized kinematics code called VISKIN has been developed by utilizing the Java programming language. The development procedure, usage, and application of the VISKIN is reported.

  15. The broad line region of AGN: Kinematics and physics

    Directory of Open Access Journals (Sweden)

    Popović L.Č.

    2006-01-01

    Full Text Available In this paper a discussion of kinematics and physics of the Broad Line Region (BLR is given. The possible physical conditions in the BLR and problems in determination of the physical parameters (electron temperature and density are considered. Moreover, one analyses the geometry of the BLR and the probability that (at least a fraction of the radiation in the Broad Emission Lines (BELs originates from a relativistic accretion disk.

  16. Interaction Between Leg Muscle Performance and Sprint Acceleration Kinematics

    Directory of Open Access Journals (Sweden)

    Lockie Robert G.

    2015-12-01

    Full Text Available This study investigated relationships between 10 m sprint acceleration, step kinematics (step length and frequency, contact and flight time, and leg muscle performance (power, stiffness, strength. Twenty-eight field sport athletes completed 10 m sprints that were timed and filmed. Velocity and step kinematics were measured for the 0-5, 5-10, and 0-10 m intervals to assess acceleration. Leg power was measured via countermovement jumps (CMJ, a fivebound test (5BT, and the reactive strength index (RSI defined by 40 cm drop jumps. Leg stiffness was measured by bilateral and unilateral hopping. A three-repetition maximum squat determined strength. Pearson’s correlations and stepwise regression (p ≤ 0.05 determined velocity, step kinematics, and leg muscle performance relationships. CMJ height correlated with and predicted velocity in all intervals (r = 0.40-0.54. The 5BT (5-10 and 0-10 m intervals and RSI (5-10 m interval also related to velocity (r = 0.37-0.47. Leg stiffness did not correlate with acceleration kinematics. Greater leg strength related to and predicted lower 0-5 m flight times (r = -0.46 to -0.51, and a longer 0-10 m step length (r = 0.38. Although results supported research emphasizing the value of leg power and strength for acceleration, the correlations and predictive relationships (r2 = 0.14-0.29 tended to be low, which highlights the complex interaction between sprint technique and leg muscle performance. Nonetheless, given the established relationships between speed, leg power and strength, strength and conditioning coaches should ensure these qualities are expressed during acceleration in field sport athletes.

  17. GPS with Real Time Kinematics on Communicator 200

    OpenAIRE

    Erlendsdottír, Linda Malin

    2012-01-01

    In today’s heavy-duty vehicles, autonomous systems are used to increase comfort and security by intervening or partially taking over the driver’s tasks. Examples of such existing systems are ABS (Anti Blocking System), EPS (Electronic Stability Program) and ACC (Autonomous Cruise Control). With access to accurate vehicle position these autonomous systems can be developed much further. One way to increase the accuracy is to use Real Time Kinematics (RTK) satellite navigation, which uses data f...

  18. From movement kinematics to social cognition: the case of autism

    Science.gov (United States)

    2016-01-01

    The way in which we move influences our ability to perceive, interpret and predict the actions of others. Thus movements play an important role in social cognition. This review article will appraise the literature concerning movement kinematics and motor control in individuals with autism, and will argue that movement differences between typical and autistic individuals may contribute to bilateral difficulties in reciprocal social cognition. PMID:27069049

  19. Kinematic viscosity of unstimulated whole saliva in healthy young adults.

    Science.gov (United States)

    Foglio-Bonda, A; Pattarino, F; Foglio-Bonda, P L

    2014-10-01

    To analyze kinematic viscosity and pH of unstimulated whole saliva, evaluate possible variations after sampling, identify any gender differences and detect possible correlations between them. The sample consisted of sixty-four healthy young adults (37 females and 27 males, mean age 25.2 years). Saliva was collected using the spitting method at 11:00 am. Kinematic viscosity was determined with a capillary viscometer (ViscoClock, Schott-Geräte Mainz, Germany) equipped with a micro-Ubbelohde capillary. Viscosity and pH were measured at a temperature of 36 °C in a thermostatic bath. Viscosity and pH data were evaluated almost simultaneously at six different times after sampling in order to identify any variations due to aging. The data were statistically analyzed using Student's t test and Wilcoxon-Mann-Whitney test. In total sample kinematic viscosity was 1.40 cSt (SD = 0.39; RSD % = 27.81), in the male and female groups was 1.33 cSt (SD = 0.35, RSD% = 26.31) and 1.45 cSt (SD = 0.41, RSD % = 28.45) respectively; the difference was not statistically significant. Viscosity decreased exponentially as a function of time after sampling then reaching a plateau around 1.12 cSt, while the pH values increased linearly. There was a trend of pH to decrease while viscosity decreases. Kinematic viscometry could be a valid tool to evaluate salivary viscosity. Degradation of saliva after sampling affects viscosity and slightly pH. The use of capillary viscometer to evaluate salivary aging needs more improvements. Further studies are required to investigate and explain the effects of different techniques to reduce the film forming on the air/liquid interface during measurement.

  20. Kinematics and kinetics during walking in individuals with gluteal tendinopathy.

    Science.gov (United States)

    Allison, Kim; Wrigley, Tim V; Vicenzino, Bill; Bennell, Kim L; Grimaldi, Alison; Hodges, Paul W

    2016-02-01

    Lateral hip pain during walking is a feature of gluteal tendinopathy but little is known how walking biomechanics differ in individuals with gluteal tendinopathy. This study aimed to compare walking kinematics and kinetics between individuals with and without gluteal tendinopathy. Three-dimensional walking-gait analysis was conducted on 40 individuals aged 35 to 70 years with unilateral gluteal tendinopathy and 40 pain-free controls. An analysis of covariance was used to compare kinematic and kinetic variables between groups. Linear regression was performed to investigate the relationship between kinematics and external hip adduction moment in the gluteal tendinopathy group. Individuals with gluteal tendinopathy demonstrated a greater hip adduction moment throughout stance than controls (standardized mean difference ranging from 0.60 (first peak moment) to 0.90 (second peak moment)). Contralateral trunk lean at the time of the first peak hip adduction moment was 1.2 degrees greater (P=0.04), and pelvic drop at the second peak hip adduction moment 1.4 degrees greater (P=0.04), in individuals with gluteal tendinopathy. Two opposite trunk and pelvic strategies were also identified within the gluteal tendinopathy group. Contralateral pelvic drop was significantly correlated with the first (R=0.35) and second peak (R=0.57) hip adduction moment, and hip adduction angle with the second peak hip adduction moment (R=-0.36) in those with gluteal tendinopathy. Individuals with gluteal tendinopathy exhibit greater hip adduction moments and alterations in trunk and pelvic kinematics during walking. Findings provide a basis to consider frontal plane pelvic control in the management of gluteal tendinopathy. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. On the kinematics of the two-photon Cherenkov effect

    International Nuclear Information System (INIS)

    Afanas'ev, G.N.; Stepanovskij, Yu.P.

    2003-01-01

    We study the kinematics of the two-photon Cherenkov effect. In the general case, the emission angles of two photons satisfy certain inequalities and the corresponding radiation intensities are rather diffused. In special cases, when the above inequalities reduce to equalities, the emission angles of two photons are fixed and the corresponding radiation intensities should have sharp maxima at these angles. This makes easier the experimental study of the two-photon Cherenkov effect

  2. Static Stiffness Modeling of Parallel Kinematics Machine Tool Joints

    OpenAIRE

    O. K. Akmaev; B. A. Enikeev; A. I. Nigmatullin

    2015-01-01

    The possible variants of an original parallel kinematics machine-tool structure are explored in this article. A new Hooke's universal joint design based on needle roller bearings with the ability of a preload setting is proposed. The bearing stiffness modeling is carried out using a variety of methods. The elastic deformation modeling of a Hook’s joint and a spherical rolling joint have been developed to assess the possibility of using these joints in machine tools with parallel k...

  3. Role of local field potentials in encoding hand movement kinematics.

    Science.gov (United States)

    Witte, Matthias

    2011-10-01

    How the brain orchestrates the musculoskeletal system to produce complex three-dimensional movements is still poorly understood. Despite first promising results in brain-machine interfaces that translate cortical activity to control output, there is an ongoing debate about which brain signals provide richest information related to movement planning and execution. Novel results by Bansal and colleagues (2011) now suggest that neuronal spiking and local field potentials jointly encode kinematics during skilled reach and grasp movements.

  4. Kinematic Characterization of Left Ventricular Chamber Stiffness and Relaxation

    Science.gov (United States)

    Mossahebi, Sina

    Heart failure is the most common cause of hospitalization today, and diastolic heart failure accounts for 40-50% of cases. Therefore, it is critical to identify diastolic dysfunction at a subclinical stage so that appropriate therapy can be administered before ventricular function is further, and perhaps irreversibly impaired. Basic concepts in physics such as kinematic modeling provide a unique method with which to characterize cardiovascular physiology, specifically diastolic function (DF). The advantage of an approach that is standard in physics, such as the kinematic modeling is its causal formulation that functions in contrast to correlative approaches traditionally utilized in the life sciences. Our research group has pioneered theoretical and experimental quantitative analysis of DF in humans, using both non-invasive (echocardiography, cardiac MRI) and invasive (simultaneous catheterization-echocardiography) methods. Our group developed and validated the Parametrized Diastolic Filling (PDF) formalism which is motivated by basic physiologic principles (LV is a mechanical suction pump at the mitral valve opening) that obey Newton's Laws. PDF formalism is a kinematic model of filling employing an equation of motion, the solution of which accurately predicts all E-wave contours in accordance with the rules of damped harmonic oscillatory motion. The equation's lumped parameters---ventricular stiffness, ventricular viscoelasticity/relaxation and ventricular load---are obtained by solving the 'inverse problem'. The parameters' physiologic significance and clinical utility have been repeatedly demonstrated in multiple clinical settings. In this work we apply our kinematic modeling approach to better understand how the heart works as it fills in order to advance the relationship between physiology and mathematical modeling. Through the use of this modeling, we thereby define and validate novel, causal indexes of diastolic function such as early rapid filling energy

  5. Interaction Between Leg Muscle Performance and Sprint Acceleration Kinematics.

    Science.gov (United States)

    Lockie, Robert G; Jalilvand, Farzad; Callaghan, Samuel J; Jeffriess, Matthew D; Murphy, Aron J

    2015-12-22

    This study investigated relationships between 10 m sprint acceleration, step kinematics (step length and frequency, contact and flight time), and leg muscle performance (power, stiffness, strength). Twenty-eight field sport athletes completed 10 m sprints that were timed and filmed. Velocity and step kinematics were measured for the 0-5, 5-10, and 0-10 m intervals to assess acceleration. Leg power was measured via countermovement jumps (CMJ), a five-bound test (5BT), and the reactive strength index (RSI) defined by 40 cm drop jumps. Leg stiffness was measured by bilateral and unilateral hopping. A three-repetition maximum squat determined strength. Pearson's correlations and stepwise regression (p ≤ 0.05) determined velocity, step kinematics, and leg muscle performance relationships. CMJ height correlated with and predicted velocity in all intervals (r = 0.40-0.54). The 5BT (5-10 and 0-10 m intervals) and RSI (5-10 m interval) also related to velocity (r = 0.37-0.47). Leg stiffness did not correlate with acceleration kinematics. Greater leg strength related to and predicted lower 0-5 m flight times (r = -0.46 to -0.51), and a longer 0-10 m step length (r = 0.38). Although results supported research emphasizing the value of leg power and strength for acceleration, the correlations and predictive relationships (r(2) = 0.14-0.29) tended to be low, which highlights the complex interaction between sprint technique and leg muscle performance. Nonetheless, given the established relationships between speed, leg power and strength, strength and conditioning coaches should ensure these qualities are expressed during acceleration in field sport athletes.

  6. Manipulation of the kinematic chain using visual biofeedback

    OpenAIRE

    Mulloy, Franky; Mullineaux, David; Irwin, Gareth

    2016-01-01

    Feedback has been shown to be an influential component in skill development, yet this has not been assessed in movements involving an explosive proximal to distal sequencing pattern. Novices (n=14) were introduced to a lunge touch task. Visual biofeedback were given on the timing and magnitude of rear leg kinematics. Results showed that those who received feedback adapted their movement patterns by developing extension velocity magnitudes in a summative pattern (pre v post, mean ± SD peak ank...

  7. A kinematic fit method for all-photon events

    International Nuclear Information System (INIS)

    Du Shuxian; Yuan Changzheng; Chinese Academy of Sciences, Beijing

    2006-01-01

    An improved kinematic fit method is developed for analyzing all-photon events, where the interaction point is unknown. The fitting algorithm is checked with Monte Carlo samples to ensure that the fitting program works properly. This is applied to the Monte Carlo simulated ψ(2S) decays. A higher efficiency is achieved. This method can be generally applied to analyzing all-photon events at electron-positron collider. (authors)

  8. Upper extremity kinematics of flat serve in tennis | Bingul | South ...

    African Journals Online (AJOL)

    The purpose of the present study was to examine of the effects of upper body kinematics on the ball velocity at the impact phase of a tennis flat serve. 15 elite male tennis players were recruited to participate in this study (mean age 18.4±3.3 years, mean height 182.3±5.6cm, mean weight 72.2±7.9kg), of which five were from ...

  9. Variations in Kinematics during Clinical Gait Analysis in Stroke Patients

    OpenAIRE

    Boudarham, Julien; Roche, Nicolas; Pradon, Didier; Bonnyaud, C?line; Bensmail, Djamel; Zory, Raphael

    2013-01-01

    In addition to changes in spatio-temporal and kinematic parameters, patients with stroke exhibit fear of falling as well as fatigability during gait. These changes could compromise interpretation of data from gait analysis. The aim of this study was to determine if the gait of hemiplegic patients changes significantly over successive gait trials. Forty two stroke patients and twenty healthy subjects performed 9 gait trials during a gait analysis session. The mean and variability of spatio-tem...

  10. MALT90 Kinematic Distances to Dense Molecular Clumps

    Energy Technology Data Exchange (ETDEWEB)

    Whitaker, J. Scott [Physics Department, Boston University, 590 Commonwealth Avenue, Boston, MA 02215 (United States); Jackson, James M.; Sanhueza, Patricio; Stephens, Ian W. [Institute for Astrophysical Research, Boston University, Boston, MA 02215 (United States); Rathborne, J. M. [CSIRO Astronomy and Space Science, P.O. Box 76, Epping NSW 1710 (Australia); Foster, J. B. [Department of Astronomy, Yale University, P.O. Box 28101, New Haven, CT 06520-8101 (United States); Contreras, Y. [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden (Netherlands); Longmore, S. N., E-mail: scott@bu.edu [Astrophysics Research Institute, Liverpool John Moores University, Egerton Wharf, Birkenhead CH41 1LD (United Kingdom)

    2017-10-01

    Using molecular-line data from the Millimetre Astronomy Legacy Team 90 GHz Survey (MALT90), we have estimated kinematic distances to 1905 molecular clumps identified in the ATLASGAL 870 μ m continuum survey over the longitude range 295° <  l  < 350°. The clump velocities were determined using a flux-weighted average of the velocities obtained from Gaussian fits to the HCO{sup +}, HNC, and N{sub 2}H{sup +} (1–0) transitions. The near/far kinematic distance ambiguity was addressed by searching for the presence or absence of absorption or self-absorption features in 21 cm atomic hydrogen spectra from the Southern Galactic Plane Survey. Our algorithm provides an estimation of the reliability of the ambiguity resolution. The Galactic distribution of the clumps indicates positions where the clumps are bunched together, and these locations probably trace the locations of spiral arms. Several clumps fall at the predicted location of the far side of the Scutum–Centaurus arm. Moreover, a number of clumps with positive radial velocities are unambiguously located on the far side of the Milky Way at galactocentric radii beyond the solar circle. The measurement of these kinematic distances, in combination with continuum or molecular-line data, now enables the determination of fundamental parameters such as mass, size, and luminosity for each clump.

  11. Evidence for halo kinematics among cool carbon-rich dwarfs

    Science.gov (United States)

    Farihi, J.; Arendt, A. R.; Machado, H. S.; Whitehouse, L. J.

    2018-04-01

    This paper reports preliminary yet compelling kinematical inferences for N ≳ 600 carbon-rich dwarf stars that demonstrate around 30% to 60% are members of the Galactic halo. The study uses a spectroscopically and non-kinematically selected sample of stars from the SDSS, and cross-correlates these data with three proper motion catalogs based on Gaia DR1 astrometry to generate estimates of their 3-D space velocities. The fraction of stars with halo-like kinematics is roughly 30% for distances based on a limited number of parallax measurements, with the remainder dominated by the thick disk, but close to 60% of the sample lie below an old, metal-poor disk isochrone in reduced proper motion. An ancient population is consistent with an extrinsic origin for C/O >1 in cool dwarfs, where a fixed mass of carbon pollution more readily surmounts lower oxygen abundances, and with a lack of detectable ultraviolet-blue flux from younger white dwarf companions. For an initial stellar mass function that favors low-mass stars as in the Galactic disk, the dC stars are likely to be the dominant source of carbon-enhanced, metal-poor stars in the Galaxy.

  12. Inverse Kinematics for Industrial Robots using Conformal Geometric Algebra

    Directory of Open Access Journals (Sweden)

    Adam L. Kleppe

    2016-01-01

    Full Text Available This paper shows how the recently developed formulation of conformal geometric algebra can be used for analytic inverse kinematics of two six-link industrial manipulators with revolute joints. The paper demonstrates that the solution of the inverse kinematics in this framework relies on the intersection of geometric objects like lines, circles, planes and spheres, which provides the developer with valuable geometric intuition about the problem. It is believed that this will be very useful for new robot geometries and other mechanisms like cranes and topside drilling equipment. The paper extends previous results on inverse kinematics using conformal geometric algebra by providing consistent solutions for the joint angles for the different configurations depending on shoulder left or right, elbow up or down, and wrist flipped or not. Moreover, it is shown how to relate the solution to the Denavit-Hartenberg parameters of the robot. The solutions have been successfully implemented and tested extensively over the whole workspace of the manipulators.

  13. Kinematics of Mass Transport Deposits revealed by magnetic fabrics

    Science.gov (United States)

    Weinberger, R.; Levi, T.; Alsop, G. I.; Marco, S.

    2017-08-01

    The internal deformation and movement directions of Mass Transport Deposits (MTDs) are key factors in understanding the kinematics and dynamics of their emplacement. Although these are relatively easy to recover from well-bedded sediments, they are more difficult to deduce from massive beds without visible strain markers. In order to test the applicability of using anisotropy of magnetic susceptibility (AMS) to determine MTD movement, we compare AMS fabrics, with structural measurements of visible kinematic indicators. Our case study involves the structural analysis of slumped lake sediments extensively exposed in MTDs within the Dead Sea Basin. Structural analyses of MTDs outcropping for >100 km reveal radial transport directions toward the basin depocenter. We show that the AMS fabrics display the same transport directions as inferred from structural analyses. Based on this similarity, we outline a robust procedure to obtain the transport direction of slumped MTDs from AMS fabrics. Variations in the magnetic fabrics and anisotropies in fold-thrust systems within the slumps match the various structural domains. We therefore suggest that magnetic fabrics and anisotropy variations in drill cores may reflect internal deformation within the slumps rather than different slumps. Obtaining magnetic fabrics from MTDs provides a viable way to infer the transport directions and internal deformation of MTDs and reconstruct the basin depocenter in ancient settings. The present results also have implications beyond the kinematics of MTDs, as their geometry resembles fold-thrust systems in other geological settings, scales, and tectonic environments.

  14. Abundances of heavy elements in the kinematic stellar substructures

    Science.gov (United States)

    Ženovienė, R.; Stonkutė, E.; Tautvaišienė, G.; Nordström, B.

    We study the chemical composition of two kinematically identified groups of stars in the Galactic disc. Based on dynamical properties these stars were suspected to belong to disrupted satellites. Using high resolution spectra obtained with the spectrograph FIES at the Nordic Optical Telescope, La Palma, we determine detailed elemental abundances of elements and look for possible chemical signatures that might give information about the formation history of these possibly accreted kinematic groups of stars. Our results reveal that abundances of chemical elements produced mainly by the r-process are overabundant and those mainly produced by the s-process are the same as in Galactic thin-disc dwarfs and models. The similar elemental abundance patterns were observed in the Galactic thick-disc stars. Similar chemical composition of project stars and the thick-disc stars might suggest that their formation histories are linked. The homogeneous chemical composition inside each of the groups together with their kinematic properties provide additional evidences of their common origin and possible relation to ancient merging events.

  15. Effects of contracture on gait kinematics: A systematic review.

    Science.gov (United States)

    Attias, Michael; Chevalley, Odile; Bonnefoy-Mazure, Alice; De Coulon, Geraldo; Cheze, Laurence; Armand, Stéphane

    2016-03-01

    Contractures of a major joint in the lower limbs may impair human walking in addition to other daily living activities. A contracture is defined as the inability of a joint to perform the full range of motion and excessive resistance during passive mobilization of the joint. Few studies have reported methods describing how to evaluate contractures. Understanding the association among all of these studies seems essential to improve patient management. Therefore, we conducted a systematic review on this topic to elucidate the influence of contractures on gait kinematics. An electronic search in the literature will be conducted. Studies were screened by title and abstract and full texts were evaluated secondarily for definitive inclusion. The quality of the included studies was assessed independently by the two review authors with the Modified Quality Assessment Checklist. The included studies were separated into three categories: pathological contracture versus healthy controls (descriptive), simulated contracture versus healthy controls (experimental), and pre- and post-kinematics after surgical muscle lengthening (surgery). From a total of 4402 references, 112 original articles were selected, and 28 studies were identified in this systematic review. No significant difference between raters was observed on the total score of the Modified Quality Assessment Checklist. Contractures influence walking depending on the location (muscle) and the contracture level (muscle-tendon length). After giving a definition of contracture, this review identified some contracture alterations, such as plantarflexion, knee flexion and hip flexion contractures, with a kinematic description and presented possible different compensations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. KINEMATIC AND KINETIC VARIABLES DIFFER BETWEEN KETTLEBELL SWING STYLES.

    Science.gov (United States)

    Bullock, Garrett S; Schmitt, Abigail C; Shutt, Jason M; Cook, Gray; Butler, Robert J

    2017-06-01

    Kettlebell (KB) and indian club swings (ICS) are used diversely for developing strength and power. It has been proposed that multiple swing techniques can be used interchangeably to elicit similar adaptations within performance training. Hypothesis/Purpose: It was hypothesized that there will be not be a difference in peak joint angles between types of swings. Furthermore, given the nature of the overhead kettlebell swing (OKS), it was hypothesized that the OKS will be associated with a greater cycle time and a greater vertical impulse compared to shoulder height swing (SKS) and ICS. The purpose of this study was to analyze the kinematics and kinetics of the SKS, OKS, and ICS. Cross-sectional cohort. Fifteen healthy subjects underwent 3D biomechanical analysis for assessment of kinematic and kinetic data. Subjects performed two trials of ten repetitions at full effort for each swing in a randomized order using either a standard set of 0.45 kg indian clubs or sex specific KB loads (Female = 12kg, Male = 20kg). Lower extremity sagittal plane kinematics and kinetics were analyzed for peak values during the down and up portions of the swing patterns. Statistical analyses were carried out utilizing one-way ANOVAs ( p power training. 2.

  17. Gait Kinematics in Individuals with Acute and Chronic Patellofemoral Pain.

    Science.gov (United States)

    Fox, Aaron; Ferber, Reed; Saunders, Natalie; Osis, Sean; Bonacci, Jason

    2018-03-01

    This study aimed to identify the discriminating kinematic gait characteristics between individuals with acute and chronic patellofemoral pain (PFP) and healthy controls. Ninety-eight runners with PFP (39 male, 59 female) and 98 healthy control runners (38 male, 60 female) ran on a treadmill at a self-selected speed while three-dimensional lower limb kinematic data were collected. Runners with PFP were split into acute (n = 25) and chronic (n = 73) subgroups on the basis of whether they had been experiencing pain for less or greater than 3 months, respectively. Principal component analysis and linear discriminant analysis were used to determine the combination of kinematic gait characteristics that optimally separated individuals with acute PFP and chronic PFP and healthy controls. Compared with controls, both the acute and chronic PFP subgroups exhibited greater knee flexion across stance and greater ankle dorsiflexion during early stance. The acute PFP subgroup demonstrated greater transverse plane hip motion across stance compared with healthy controls. In contrast, the chronic PFP subgroup demonstrated greater frontal plane hip motion, greater knee abduction, and reduced ankle eversion/greater ankle inversion across stance when compared with healthy controls. This study identified characteristics that discriminated between individuals with acute and chronic PFP when compared with healthy controls. Certain discriminating characteristics were shared between both the acute and chronic subgroups when compared with healthy controls, whereas others were specific to the duration of PFP.

  18. INFLUENCE OF GONARTHROSIS ON KINEMATICS INDICATORS OF THE KNEE JOINT

    Directory of Open Access Journals (Sweden)

    S. I. Loginov

    2016-01-01

    Full Text Available Aim. To establish peculiarity of the influence of gonarthrosis on kinematics indices of the knee joint at people at the age of 45–60 with the help of markless motion method.Materials and methods. In the research 81 people took part. In the group of the control entered 42 people without symptomatic evidences of gonarthrosis, in the experimental group – 39 people with gonarthrosis of the 1 and 2 degrees at the age of 40 to 65. With the help of the markless motion method and software Brekel Pro Body» was made biomechanical analysis of the kinematics of knee joints.Results. It is established that people at the age of 40 to 65, suffering with gonarthrosis have authentically more angular moments of lateral mode of motions and rotations in knee joints.Conclusion. Under analysis of the kinematics of knee joints, between the control and the experimental groups were fixed significant differences (t-test, p < 0,01. Besides there were fixed differences between dominant and non-dominant limbs, which mean that the force of muscles of lower limbs can also be a modificative factor, which influences on the strain in joints that potentially can lead to the development and/or advance of degenerative damage in the knee joint. 

  19. Pa2 kinematic bond in translational parallel manipulators

    Directory of Open Access Journals (Sweden)

    A. Hernández

    2018-01-01

    Full Text Available The Pa2 pair is composed of two intertwined articulated parallelograms connecting in parallel two links of a kinematic chain. This pair has two translational degrees of freedom leading to a translational plane variable with the position. Currently, the Pa2 pair appears in conceptual designs presented in recent papers. However, its practical application is very limited. One of the reasons for this can be the high number of redundant constraints it has. But, it has to be considered that most of them can be eliminated by replacing wisely the revolute joints by spherical joints. On the other side, the structure of the Pa2 pair contributes to increase the global stiffness of the kinematic chain in which it is mounted. Also, its implementation is a promising alternative to the problematic passive prismatic joints. In this paper, the Pa2 pairs are used in the design of a 3 − P Pa2 parallel manipulator. The potentiality of this design is evaluated and proven after doing the following analyses: direct and inverse kinematics, singularity study, and workspace computation and assessment.

  20. The kinematic features of motorcycles in congested urban networks.

    Science.gov (United States)

    Lee, Tzu-Chang; Polak, John W; Bell, Michael G H; Wigan, Marcus R

    2012-11-01

    The aim of this paper is to compare the kinematic features of motorcycles with those of passenger cars in urban traffic. The hypothesis that motorcycles' capability to swerve in urban traffic contributes to their seemingly assertive behaviour is examined. Data for this study were collected in afternoon peak hours at Central London using video recorders. Detailed information on the trajectories of 2109 vehicles (including 477 motorcycles and 1293 passenger cars) was extracted from the video images and the observable kinematic features were analysed. In addition, a model describing the longitudinal following behaviour of motorcycles was employed to analyse the impacts of motorcycles' swerving behaviour. The model was calibrated using Markov Chain Monte Carlo (MCMC) numerical methods. The observable kinematic features show that in comparison to passenger cars, motorcycles have shorter safety gaps, higher speeds and severer acceleration and deceleration rates reflecting their generally much higher power to weight ratios and usage of available braking power. However, the data also support the hypothesis that motorcyclists maintain a considerable safety margin as they have the ability to avoid a collision by swerving away. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Analysis of a closed-kinematic chain robot manipulator

    Science.gov (United States)

    Nguyen, Charles C.; Pooran, Farhad J.

    1988-01-01

    Presented are the research results from the research grant entitled: Active Control of Robot Manipulators, sponsored by the Goddard Space Flight Center (NASA) under grant number NAG-780. This report considers a class of robot manipulators based on the closed-kinematic chain mechanism (CKCM). This type of robot manipulators mainly consists of two platforms, one is stationary and the other moving, and they are coupled together through a number of in-parallel actuators. Using spatial geometry and homogeneous transformation, a closed-form solution is derived for the inverse kinematic problem of the six-degree-of-freedom manipulator, built to study robotic assembly in space. Iterative Newton Raphson method is employed to solve the forward kinematic problem. Finally, the equations of motion of the above manipulators are obtained by employing the Lagrangian method. Study of the manipulator dynamics is performed using computer simulation whose results show that the robot actuating forces are strongly dependent on the mass and centroid locations of the robot links.

  2. The Effect of Direction on Cursor Moving Kinematics

    Directory of Open Access Journals (Sweden)

    Chiu-Ping Lu

    2012-02-01

    Full Text Available There have been only few studies to substantiate the kinematic characteristics of cursor movement. In this study, a quantitative experimental research method was used to explore the effect of moving direction on the kinematics of cursor movement in 24 typical young persons using our previously developed computerized measuring program. The results of multiple one way repeated measures ANOVAs and post hoc LSD tests demonstrated that the moving direction had effects on average velocity, movement time, movement unit and peak velocity. Moving leftward showed better efficiency than moving rightward, upward and downward from the kinematic evidences such as velocity, movement unit and time. Moreover, the unique pattern of the power spectral density (PSD of velocity (strategy for power application explained why the smoothness was still maintained while moving leftward even under an unstable situation with larger momentum. Moreover, the information from this cursor moving study can guide us to relocate the toolbars and icons in the window interface, especially for individuals with physical disabilities whose performances are easily interrupted while controlling the cursor in specific directions.

  3. Kinematic gait patterns in healthy runners: A hierarchical cluster analysis.

    Science.gov (United States)

    Phinyomark, Angkoon; Osis, Sean; Hettinga, Blayne A; Ferber, Reed

    2015-11-05

    Previous studies have demonstrated distinct clusters of gait patterns in both healthy and pathological groups, suggesting that different movement strategies may be represented. However, these studies have used discrete time point variables and usually focused on only one specific joint and plane of motion. Therefore, the first purpose of this study was to determine if running gait patterns for healthy subjects could be classified into homogeneous subgroups using three-dimensional kinematic data from the ankle, knee, and hip joints. The second purpose was to identify differences in joint kinematics between these groups. The third purpose was to investigate the practical implications of clustering healthy subjects by comparing these kinematics with runners experiencing patellofemoral pain (PFP). A principal component analysis (PCA) was used to reduce the dimensionality of the entire gait waveform data and then a hierarchical cluster analysis (HCA) determined group sets of similar gait patterns and homogeneous clusters. The results show two distinct running gait patterns were found with the main between-group differences occurring in frontal and sagittal plane knee angles (Pgait strategies. These results suggest care must be taken when selecting samples of subjects in order to investigate the pathomechanics of injured runners. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Variations in Kinematics during Clinical Gait Analysis in Stroke Patients

    Science.gov (United States)

    Boudarham, Julien; Roche, Nicolas; Pradon, Didier; Bonnyaud, Céline; Bensmail, Djamel; Zory, Raphael

    2013-01-01

    In addition to changes in spatio-temporal and kinematic parameters, patients with stroke exhibit fear of falling as well as fatigability during gait. These changes could compromise interpretation of data from gait analysis. The aim of this study was to determine if the gait of hemiplegic patients changes significantly over successive gait trials. Forty two stroke patients and twenty healthy subjects performed 9 gait trials during a gait analysis session. The mean and variability of spatio-temporal and kinematic joint parameters were analyzed during 3 groups of consecutive gait trials (1–3, 4–6 and 7–9). Principal component analysis was used to reduce the number of variables from the joint kinematic waveforms and to identify the parts of the gait cycle which changed during the gait analysis session. The results showed that i) spontaneous gait velocity and the other spatio-temporal parameters significantly increased, and ii) gait variability decreased, over the last 6 gait trials compared to the first 3, for hemiplegic patients but not healthy subjects. Principal component analysis revealed changes in the sagittal waveforms of the hip, knee and ankle for hemiplegic patients after the first 3 gait trials. These results suggest that at the beginning of the gait analysis session, stroke patients exhibited phase of adaptation,characterized by a “cautious gait” but no fatigue was observed. PMID:23799100

  5. Accurate isotopic fission yields of electromagnetically induced fission of 238U measured in inverse kinematics at relativistic energies

    Science.gov (United States)

    Pellereau, E.; Taïeb, J.; Chatillon, A.; Alvarez-Pol, H.; Audouin, L.; Ayyad, Y.; Bélier, G.; Benlliure, J.; Boutoux, G.; Caamaño, M.; Casarejos, E.; Cortina-Gil, D.; Ebran, A.; Farget, F.; Fernández-Domínguez, B.; Gorbinet, T.; Grente, L.; Heinz, A.; Johansson, H.; Jurado, B.; Kelić-Heil, A.; Kurz, N.; Laurent, B.; Martin, J.-F.; Nociforo, C.; Paradela, C.; Pietri, S.; Rodríguez-Sánchez, J. L.; Schmidt, K.-H.; Simon, H.; Tassan-Got, L.; Vargas, J.; Voss, B.; Weick, H.

    2017-05-01

    SOFIA (Studies On Fission with Aladin) is a novel experimental program, dedicated to accurate measurements of fission-fragment isotopic yields. The setup allows us to fully identify, in nuclear charge and mass, both fission fragments in coincidence for the whole fission-fragment range. It was installed at the GSI facility (Darmstadt), to benefit from the relativistic heavy-ion beams available there, and thus to use inverse kinematics. This paper reports on fission yields obtained in electromagnetically induced fission of 238U.

  6. Gait in adolescent idiopathic scoliosis: kinematics and electromyographic analysis.

    Science.gov (United States)

    Mahaudens, P; Banse, X; Mousny, M; Detrembleur, C

    2009-04-01

    Adolescent idiopathic scoliosis (AIS) is a progressive growth disease that affects spinal anatomy, mobility, and left-right trunk symmetry. Consequently, AIS can modify human locomotion. Very few studies have investigated a simple activity like walking in a cohort of well-defined untreated patients with scoliosis. The first goal of this study is to evaluate the effects of scoliosis and scoliosis severity on kinematic and electromyographic (EMG) gait variables compared to an able-bodied population. The second goal is to look for any asymmetry in these parameters during walking. Thirteen healthy girls and 41 females with untreated AIS, with left thoracolumbar or lumbar primary structural curves were assessed. AIS patients were divided into three clinical subgroups (group 1 40 degrees). Gait analysis included synchronous bilateral kinematic and EMG measurements. The subjects walked on a treadmill at 4 km/h (comfortable speed). The tridimensional (3D) shoulder, pelvis, and lower limb motions were measured using 22 reflective markers tracked by four infrared cameras. The EMG timing activity was measured using bipolar surface electrodes on quadratus lumborum, erector spinae, gluteus medius, rectus femoris, semitendinosus, tibialis anterior, and gastrocnemius muscles. Statistical comparisons (ANOVA) were performed across groups and sides for kinematic and EMG parameters. The step length was reduced in AIS compared to normal subjects (7% less). Frontal shoulder, pelvis, and hip motion and transversal hip motion were reduced in scoliosis patients (respectively, 21, 27, 28, and 22% less). The EMG recording during walking showed that the quadratus lumborum, erector spinae, gluteus medius, and semitendinosus muscles contracted during a longer part of the stride in scoliotic patients (46% of the stride) compared with normal subjects (35% of the stride). There was no significant difference between scoliosis groups 1, 2, and 3 for any of the kinematic and EMG parameters, meaning

  7. On use of radial evanescence remain term in kinematic hardening

    International Nuclear Information System (INIS)

    Geyer, P.

    1995-10-01

    A fine modelling of the material' behaviour can be necessary to study the mechanical strength of nuclear power plant' components under cyclic loads. Ratchetting is one of the last phenomena for which numerical models have to be improved. We discuss in this paper on use of radial evanescence remain term in kinematic hardening to improve the description of ratchetting in biaxial loading tests. It's well known that Chaboche elastoplastic model with two non linear kinematic hardening variables initially proposed by Armstrong and Frederick, usually over-predicts accumulation of ratchetting strain. Burlet and Cailletaud proposed in 1987 a non linear kinematic rule with a radial evanescence remain term. The two models lead to identical formulation for proportional loadings. In the case of a biaxial loading test (primary+secondary loading), Burlet and Cailletaud model leads to accommodation, when Chaboche one's leads to ratchetting with a constant increment of strain. So we can have an under-estimate with the first model and an over-estimate with the second. An easy method to improve the description of ratchetting is to combine the two kinematic rules. Such an idea is already used by Delobelle in his model. With analytical results in the case of tension-torsion tests, we show in a first part of the paper, the interest of radial evanescence remain term in the non linear kinematic rule to describe ratchetting: we give the conditions to get adaptation, accommodation or ratchetting and the value of the strain increment in the last case. In the second part of the paper, we propose to modify the elastoplastic Chaboche model by coupling the two types of hardening by means of two scalar parameters which can be identified independently on biaxial loading tests. Identification of these two parameters returns to speculate on the directions of strain in order to adjust the ratchetting to experimental observations. We use the experimental results on the austenitic steel 316L at room

  8. Digital video, learning styles, and student understanding of kinematics graphs

    Science.gov (United States)

    Hein, Teresa Lee

    1997-12-01

    Student ability to analyze and interpret motion graphs following laboratory instruction that utilized interactive digital video as well as traditional instructional techniques was investigated. Research presented suggested that digital video tools serve to motivate students and may be an effective mechanism to enhance student understanding of motion concepts. Two laboratory exercises involving motion concepts were developed for this study. Students were divided into two instructional groups. The treatment group used digital video techniques and the control group used traditional techniques to perform the laboratory exercises. Student understanding of motion concepts were assessed, in part, using the Test of Understanding Graphs-Kinematics. Other assessment measures included student responses to a set of written graphical analysis questions and two post-lab activities. Possible relationships between individual learning style preferences and student understanding of motion concepts were also addressed. Learning style preferences were assessed using the Productivity Environmental Preference Survey prior to the instructional treatments. Students were asked to comment in writing about their learning styles before and after they were given the learning style assessment. Student comments revealed that the results they received from Productivity Environmental Preference Survey accurately reflected their learning styles. Results presented in this study showed that no significant relationship exists between students' learning style preferences and their ability to interpret motion graphs as measured by scores on the Test of Understanding Graphs-Kinematics. In addition, the results showed no significant difference between instructional treatment and mean scores on the Test of Understanding Graphs-Kinematics. Analysis of writing activities revealed that students in the treatment group responded more effectively than students in the control group to graphical interpretation

  9. Zooming in on Extreme Environments: Using JVLA Observations and Kinematic Models of Arp 220 to Study Physical Conditions in ULIRGs

    Science.gov (United States)

    Zschaechner, Laura K.; Walter, Fabian; Ott, Juergen; Momjian, Emmanuel; Meier, David S.

    2015-01-01

    Using new Jansky VLA capabilities we observe Arp 220, the nearest ULIRG. With a high star formation rate similar to high-z galaxies, but at a close distance from the Milky Way, Arp 220 allows us to explore these extreme conditions at high resolution. With the availability of high-frequency (K, Ka, and Q band) receivers and wide bandwidths, we detect multiple line species, in particular multiple metastable ammonia inversions which are excellent tracers of kinetic temperature and density. Conditions and composition vary greatly throughout Arp 220, especially when offset from the two bright nuclei. By characterizing the temperature and density throughout the system, we can better understand the conditions associated with high star formation rates, which can then be applied to ULIRGs at high-z. Additionally, the strength and isolation of some lines allows for detailed kinematic modeling in both absorption and emission, allowing us to isolate anomalous material and characterize the dynamics of the system.

  10. Acoustic and tongue kinematic vowel space in speakers with and without dysarthria.

    Science.gov (United States)

    Lee, Jimin; Littlejohn, Meghan Anne; Simmons, Zachary

    2017-04-01

    The purpose is to investigate acoustic and tongue body kinematic vowel dispersion patterns and vowel space in speakers with and without dysarthria secondary to amyotrophic lateral sclerosis (ALS). Acoustic and tongue kinematic vowel spaces were examined at the same time sampling point using electromagnetic articulography in 11 speakers with dysarthria secondary to ALS and 11 speakers without dysarthria. Tongue kinematic data were collected from the tongue body sensor (∼25 mm posterior from the tongue apex). A number of acoustic and tongue body kinematic variables were tested. The result showed that the acoustic and tongue kinematic vowel dispersion patterns are different between the groups. Acoustic and tongue body kinematic vowel spaces are highly correlated; however, unlike acoustic vowel space, tongue body kinematic vowel space was not significantly different between the groups. Both acoustic and tongue kinematic vowel dispersion patterns are sensitive to the group difference, especially with high vowels. The tongue kinematic vowel space approach is too crude to differentiate the speakers with dysarthria secondary to ALS from speakers without dysarthria. To examine tongue range of motion in speakers with dysarthria, a more refined articulatory kinematic approach needs to be examined in the future.

  11. Differences between kinematic synergies and muscle synergies during two-digit grasping

    Directory of Open Access Journals (Sweden)

    Michele eTagliabue

    2015-03-01

    Full Text Available The large number of mechanical degrees of freedom of the hand is not fully exploited during actual movements such as grasping. Usually, angular movements in various joints tend to be coupled, and EMG activities in different hand muscles tend to be correlated. The occurrence of covariation in the former was termed kinematic synergies, in the latter muscle synergies. This study addresses two questions: (i Whether kinematic and muscle synergies can simultaneously accommodate for kinematic and kinetic constraints. (ii If so, whether there is an interrelation between kinematic and muscle synergies. We used a reach-grasp-and-pull paradigm and recorded the hand kinematics as well as 8 surface EMGs. Subjects had to either perform a precision grip or side grip and had to modify their grip force in order to displace an object against a low or high load. The analysis was subdivided into three epochs: reach, grasp-and-pull, and static hold. Principal component analysis (PCA, temporal or static was performed separately for all three epochs, in the kinematic and in the EMG domain. PCA revealed that (i Kinematic- and muscle-synergies can simultaneously accommodate kinematic (grip type and kinetic task constraints (load condition. (ii Upcoming grip and load conditions of the grasp are represented in kinematic- and muscle-synergies already during reach. Phase plane plots of the principal muscle-synergy against the principal kinematic synergy revealed (iii that the muscle-synergy is linked (correlated, and in phase advance to the kinematic synergy during reach and during grasp-and-pull. Furthermore (iv, pair-wise correlations of EMGs during hold suggest that muscle-synergies are (in part implemented by coactivation of muscles through common input. Together, these results suggest that kinematic synergies have (at least in part their origin not just in muscular activation, but in synergiestic muscle activation. In short: kinematic synergies may result from muscle

  12. 49 CFR 230.24 - Maximum allowable stress.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Maximum allowable stress. 230.24 Section 230.24... Allowable Stress § 230.24 Maximum allowable stress. (a) Maximum allowable stress value. The maximum allowable stress value on any component of a steam locomotive boiler shall not exceed 1/4 of the ultimate...

  13. Kinematic analysis of modern dance movement “stag jump” within the context of impact loads, injury to the locomotor system and its prevention

    Science.gov (United States)

    Gorwa, Joanna; Dworak, Lechosław B.; Michnik, Robert; Jurkojć, Jacek

    2014-01-01

    Background This paper presents a case study of kinematic analysis of the modern dance movement known as the “stag jump”. Detailed analysis of the kinematic structure of this movement as performed by the dancers, accompanied by measurements of impact forces during landing, will allow the authors to determine, in subsequent model-based research phases, the forces acting in knee joints of the lower landing limb. Material/Methods Two professional modern dancers participated in the study: a male and a female. The study consisted in recording the values of ground reaction and body motion, and then determining and analyzing kinematic parameters of performed movements. Results The results of measurement of joint angles in the landing lower limb, pelvis, and foot position in relation to the ground, as well as the level of vertical components of ground reaction, provided insight into the loading response phase of the “stag jump”. The measurements and obtained results show differences between the man and woman in ground reactions and kinematic quantities. Conclusions The results obtained during the research may be used in the development and teaching of dancing movements. Training sessions, carried out in the biomechanical laboratory, with active participation of dancing teachers, could form a basis for a prevention model of injuries and physical overloads occurring within this occupational group. Primary differences in the “stag jump” performance technique probably result from the different educational path the man and the woman went through. PMID:24971626

  14. Kinematic analysis of modern dance movement "stag jump" within the context of impact loads, injury to the locomotor system and its prevention.

    Science.gov (United States)

    Gorwa, Joanna; Dworak, Lechosław B; Michnik, Robert; Jurkojć, Jacek

    2014-06-27

    This paper presents a case study of kinematic analysis of the modern dance movement known as the "stag jump". Detailed analysis of the kinematic structure of this movement as performed by the dancers, accompanied by measurements of impact forces during landing, will allow the authors to determine, in subsequent model-based research phases, the forces acting in knee joints of the lower landing limb. Two professional modern dancers participated in the study: a male and a female. The study consisted in recording the values of ground reaction and body motion, and then determining and analyzing kinematic parameters of performed movements. The results of measurement of joint angles in the landing lower limb, pelvis, and foot position in relation to the ground, as well as the level of vertical components of ground reaction, provided insight into the loading response phase of the "stag jump". The measurements and obtained results show differences between the man and woman in ground reactions and kinematic quantities. The results obtained during the research may be used in the development and teaching of dancing movements. Training sessions, carried out in the biomechanical laboratory, with active participation of dancing teachers, could form a basis for a prevention model of injuries and physical overloads occurring within this occupational group. Primary differences in the "stag jump" performance technique probably result from the different educational path the man and the woman went through.

  15. Evidence-based recommendations for musculoskeletal kinematic 4D-CT studies using wide area-detector scanners: a phantom study with cadaveric correlation

    Energy Technology Data Exchange (ETDEWEB)

    Gondim Teixeira, Pedro Augusto; Formery, Anne-Sophie; Blum, Alain [CHRU-Nancy Hopital Central, Service d' Imagerie Guilloz, Nancy (France); Hossu, Gabriela [Universite de Lorraine, IADI U947, Nancy (France); INSERM, CIC-IT 1433, Nancy (France); Winninger, Daniel [IDCmem, Nancy (France); Batch, Toufik [Hopital de Mercy, Service de Radiologie, Metz (France); Gervaise, Alban [Legouest Military Instruction Hospital, Medical Imaging Department, Metz (France)

    2017-02-15

    To establish evidence-based recommendations for musculoskeletal kinematic 4D-CT on wide area-detector CT. In order to assess factors influencing image quality in kinematic CT studies, a phantom consisting of a polymethylmethacrylate rotating disk with round wells of different sizes was imaged with various acquisition protocols. Cadaveric acquisitions were performed on the ankle joint during motion in two different axes and at different speeds to allow validation of phantom data. Images were acquired with a 320 detector-row CT scanner and were evaluated by two readers. Motion artefacts were significantly correlated with various parameters (movement axis, distance to centre, rotation speed and volume acquisition speed) (p < 0.0001). The relation between motion artefacts and distance to motion fulcrum was exponential (R{sup 2} 0.99). Half reconstruction led to a 23 % increase in image noise and a 40 % decrease in motion artefacts. Cadaveric acquisitions confirmed phantom data. Based on these findings, high tube rotation speed and half reconstruction are recommended for kinematic CT. The axis of motion significantly influences image artefacts and should be considered in patient training and evaluation of acquisition protocol suitability. This study provides evidence-based recommendations for musculoskeletal kinematic 4D-CT. (orig.)

  16. A DETAILED MORPHO-KINEMATIC MODEL OF THE ESKIMO, NGC 2392: A UNIFYING VIEW WITH THE CAT'S EYE AND SATURN PLANETARY NEBULAE

    International Nuclear Information System (INIS)

    García-Díaz, Ma. T.; López, J. A.; Steffen, W.; Richer, M. G.

    2012-01-01

    The three-dimensional and kinematic structure of the Eskimo nebula, NGC 2392, has been notoriously difficult to interpret in detail given its complex morphology, multiple kinematic components and its nearly pole-on orientation along the line of sight. We present a comprehensive, spatially resolved, high-resolution, long-slit spectroscopic mapping of the Eskimo planetary nebula. The data consist of 21 spatially resolved, long-slit echelle spectra tightly spaced over the Eskimo and along its bipolar jets. This data set allows us to construct a velocity-resolved [N II] channel map of the nebula with a resolution of 10 km s –1 that disentangles its different kinematic components. The spectroscopic information is combined with Hubble Space Telescope images to construct a detailed three-dimensional morpho-kinematic model of the Eskimo using the code SHAPE. With this model we demonstrate that the Eskimo is a close analog to the Saturn and the Cat's Eye nebulae, but rotated 90° to the line of sight. Furthermore, we show that the main characteristics of our model apply to the general properties of the group of elliptical planetary nebulae with ansae or FLIERS, once the orientation is considered. We conclude that this kind of nebula belongs to a class with a complex common evolutionary sequence of events.

  17. Analysing the Hydraulic Actuator-based Knee Unit Kinematics and Correlating the Numerical Results and Walking Human Knee Joint Behavior

    Directory of Open Access Journals (Sweden)

    K. A. Trukhanov

    2014-01-01

    Full Text Available State-of-the-art machinery development enables people with lost lower limb to continue their previous life despite a loss. International companies dealing with this area pursue a minimization of human behaviour problems because of amputation. Researches to create an optimal design of the artificial knee joint are under way.The work task was to define analytical relationships of changing kinematic parameters of the human walking on the flat surface such as an angle of the knee joint, knee point (moment, definition of reduced knee actuator (A load, as well as to compare obtained results with experimental data.As an A in created design, the article proposes to use a controlled shock absorber based on the hydraulic cylinder.A knee unit is a kinematic two-tier mechanism. One of the mechanism links performs rotational motion, and the other is rotation-translational to provide a rotation of the first one.When studying the hydraulic actuator device dynamics, as a generalized coordinate a coordinate of the piston x (or ρ position is chosen while in the study of link movements an angle β is preferable.Experimental data are obtained for a human with the body weight of 57.6 kg walking on the flat surface to estimate a value of the knee joint angle, speed, acceleration, torque, and capacity in the knee joint and are taken from the published works of foreign authors.A trigonometric approximation was used for fitting the experimental data. The resulting dependence of the reduced load on the stock of A is necessary to perform the synthesis of A. The criterion for linear mechanisms mentioned in the D.N. Popov’s work is advisable to use as a possible criterion for optimization of A.The results obtained are as follows:1. Kinematics linkage mechanism is described using relationships for dependencies of its geometrical parameters, namely a cylinder piston stroke x (or ρ and a links angle β.2. Obtained polynomials of kinematic relationships allow a synthesis of

  18. The role of mechanics and kinematics on the Arctic sea ice decline

    Science.gov (United States)

    Weiss, J.

    2011-12-01

    IPCC AR4 climate models unforeseen the recent Arctic sea ice decline, either in terms of extent or thinning rate. Owing to the complexity of the Arctic basin as a physical system involving many interacting processes and feedbacks (negative or positive), several tracks are currently followed to try to improve the representation of these processes. Here we focus on the representation of sea ice mechanics and kinematics (drift, deformation). Indeed, the spectacular evolution of the Arctic sea ice cover is not restricted to the shrinking of ice extent or to thinning. Kinematics is affected as well, and its evolution plays a central role in the changes underwent nowadays in the Arctic ocean. As observed from buoy drift data, the sea ice mean speed increased at a rate of 9% per decade from 1979 to 2007, whereas the mean deformation rate increased by more than 50% per decade over the same period. These two aspects of recent sea ice evolution, i.e. strong decline and accelerated kinematics, are likely intimately coupled. Increasing deformation means stronger fracturing, hence more lead opening and a decreasing albedo. As a result, ocean warming, in turn, favors sea ice thinning in summer and delays refreezing in early winter, i.e. strengthens sea ice decline. This thinning decreases the mechanical strength, therefore allowing even more fracturing, hence larger speed and deformation. A consequence is the acceleration of sea ice export through Fram or Nares Strait with a significant impact on sea ice mass balance. The coupling between the ice state (thickness and concentration) and ice velocity is unexpectedly weak in most IPCC AR4 models. In particular, sea ice drifts faster during the months when it is thick and packed than when it is thin, contrary to what is observed; also models with larger long-term thinning trends do not show higher drift acceleration. This weak coupling behavior (i) suggests that the positive feedbacks mentioned above are underestimated, and (ii) can

  19. Wingbeat kinematics and motor control of yaw turns in Anna's hummingbirds (Calypte anna).

    Science.gov (United States)

    Altshuler, Douglas L; Quicazán-Rubio, Elsa M; Segre, Paolo S; Middleton, Kevin M

    2012-12-01

    The biomechanical and neuromuscular mechanisms used by different animals to generate turns in flight are highly variable. Body size and body plan exert some influence, e.g. birds typically roll their body to orient forces generated by the wings whereas insects are capable of turning via left-right wingbeat asymmetries. Turns are also relatively brief and have low repeatability, with almost every wingbeat serving a different function throughout the change in heading. Here we present an analysis of Anna's hummingbirds (Calypte anna) as they fed continuously from an artificial feeder revolving around the outside of the animal. This setup allowed for examination of sustained changes in yaw without requiring any corresponding changes in pitch, roll or body position. Hummingbirds sustained yaw turns by expanding the wing stroke amplitude of the outer wing during the downstroke and by altering the deviation of the wingtip path during both downstroke and upstroke. The latter led to a shift in the inner-outer stroke plane angle during the upstroke and shifts in the elevation of the stroke plane and in the deviation of the wingtip path during both strokes. These features are generally more similar to how insects, as opposed to birds, turn. However, time series analysis also revealed considerable stroke-to-stroke variation. Changes in the stroke amplitude and the wingtip velocity were highly cross-correlated, as were changes in the stroke deviation and the elevation of the stroke plane. As was the case for wingbeat kinematics, electromyogram recordings from pectoral and wing muscles were highly variable, but no correlations were found between these two features of motor control. The high variability of both kinematic and muscle activation features indicates a high level of wingbeat-to-wingbeat adjustments during sustained yaw. The activation timing of the muscles was more repeatable than the activation intensity, which suggests that the former may be constrained by harmonic

  20. A novel probe design to study wetting front kinematics during forced convective quenching

    Energy Technology Data Exchange (ETDEWEB)

    Vergara-Hernandez, H.J.; Hernandez-Morales, B. [Facultad de Quimica, Departamento de Ingenieria Metalurgica, Universidad Nacional Autonoma de Mexico, Circuito Interior s/n, Mexico, DF 04510 (Mexico)

    2009-07-15

    The kinematics of the wetting front, i.e., the loci of the boundary between stable vapor film and the presence of bubbles, during quenching operations largely determines the evolution of the microstructural and displacement fields which, in turn, control the properties of the quenched product. Thus, it is important to develop techniques that allow its precise characterization. To this end, a novel probe design (conical-end cylinder) was coupled with an experimental set-up that guarantees fully developed flow to study wetting front kinematics during forced convective quenching of AISI 304 stainless steel probes in water at 60 C, flowing at 0.20 and 0.60 m/s. Conventional probes (flat-end cylinder) were also quenched for comparison. The wetting front was not symmetric when flat-end cylindrical probes were quenched, even for fully developed flow and relatively low values of quenchant velocity. Computer simulation of the vorticity field near the probe base (considering an isothermal system at ambient temperature) showed that there is a significant vorticity gradient in that region which may favour the chaotic collapse of the vapor film. In contrast, a similar calculation did not show any noticeable vorticity gradient for the conical-end cylindrical probe even at high quenchant velocities. The conical-end cylindrical probe and a fully developed flow ensured that the vapor film collapsed uniformly around the probe due to the fact that the formation of the wetting front was concentrated, initially, at the probe tip. This condition permits a constant advance of the wetting front and a stable transition between boiling regimes, facilitating the study of the kinematics of the wetting front. For the experimental conditions studied the following parameters were derived: (1) wetting front velocity, (2) nucleate boiling length, (3) duration of the nucleate boiling stage and (4) width of the vapor film. The duration of the nucleate boiling stage could be estimated using existing

  1. Radiographic-directed local coordinate systems critical in kinematic analysis of walking in diabetes-related medial column foot deformity.

    Science.gov (United States)

    Hastings, Mary K; Woodburn, James; Mueller, Michael J; Strube, Michael J; Johnson, Jeffrey E; Beckert, Krista S; Stein, Michelle L; Sinacore, David R

    2014-01-01

    Diabetic foot deformity onset and progression maybe associated with abnormal foot and ankle motion. The modified Oxford multi-segmental foot model allows kinematic assessment of inter-segmental foot motion. However, there are insufficient anatomical landmarks to accurately representation the alignment of the hindfoot and forefoot segments during model construction. This is most notable for the sagittal plane which is referenced parallel to the floor, allowing comparison of inter-segmental excursion but not capturing important sagittal hind-to-forefoot deformity associated with diabetic foot disease and can potentially underestimate true kinematic differences. The purpose of the study was to compare walking kinematics using local coordinate systems derived from the modified Oxford model and the radiographic directed model which incorporated individual calcaneal and 1st metatarsal declination pitch angles for the hindfoot and forefoot. We studied twelve participants in each of the following groups: (1) diabetes mellitus, peripheral neuropathy and medial column foot deformity (DMPN+), (2) DMPN without medial column deformity (DMPN-) and (3) age- and weight-match controls. The modified Oxford model coordinate system did not identify differences between groups in the initial, peak, final, or excursion hindfoot relative to shank or forefoot relative to hindfoot dorsiflexion/plantarflexion during walking. The radiographic coordinate system identified the DMPN+ group to have an initial, peak and final position of the forefoot relative to hindfoot that was more dorsiflexed (lower arch phenotype) than the DMPN- group (pfoot deformity reveals segmental motion occurring upon alignment indicative of a lower arch. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Quantifying kinematic differences between land and water during squats, split squats, and single-leg squats in a healthy population.

    Directory of Open Access Journals (Sweden)

    Anna C Severin

    Full Text Available Aquatic exercises can be used in clinical and sporting disciplines for both rehabilitation and sports training. However, there is limited knowledge on the influence of water immersion on the kinematics of exercises commonly used in rehabilitation and fitness programs. The aim of this study was to use inertial sensors to quantify differences in kinematics and movement variability of bodyweight squats, split squats, and single-leg squats performed on dry land and whilst immersed to the level of the greater trochanter. During two separate testing sessions, 25 active healthy university students (22.3±2.9 yr. performed ten repetitions of each exercise, whilst tri-axial inertial sensors (100 Hz recorded their trunk and lower body kinematics. Repeated-measures statistics tested for differences in segment orientation and speed, movement variability, and waveform patterns between environments, while coefficient of variance was used to assess differences in movement variability. Between-environment differences in segment orientation and speed were portrayed by plotting the mean difference ±95% confidence intervals (CI throughout the tasks. The results showed that the depth of the squat and split squat were unaffected by the changed environment while water immersion allowed for a deeper single leg squat. The different environments had significant effects on the sagittal plane orientations and speeds for all segments. Water immersion increased the degree of movement variability of the segments in all exercises, except for the shank in the frontal plane, which showed more variability on land. Without compromising movement depth, the aquatic environment induces more upright trunk and shank postures during squats and split squats. The aquatic environment allows for increased squat depth during the single-leg squat, and increased shank motions in the frontal plane. Our observations therefore support the use of water-based squat tasks for rehabilitation as

  3. Quantifying kinematic differences between land and water during squats, split squats, and single-leg squats in a healthy population.

    Science.gov (United States)

    Severin, Anna C; Burkett, Brendan J; McKean, Mark R; Wiegand, Aaron N; Sayers, Mark G L

    2017-01-01

    Aquatic exercises can be used in clinical and sporting disciplines for both rehabilitation and sports training. However, there is limited knowledge on the influence of water immersion on the kinematics of exercises commonly used in rehabilitation and fitness programs. The aim of this study was to use inertial sensors to quantify differences in kinematics and movement variability of bodyweight squats, split squats, and single-leg squats performed on dry land and whilst immersed to the level of the greater trochanter. During two separate testing sessions, 25 active healthy university students (22.3±2.9 yr.) performed ten repetitions of each exercise, whilst tri-axial inertial sensors (100 Hz) recorded their trunk and lower body kinematics. Repeated-measures statistics tested for differences in segment orientation and speed, movement variability, and waveform patterns between environments, while coefficient of variance was used to assess differences in movement variability. Between-environment differences in segment orientation and speed were portrayed by plotting the mean difference ±95% confidence intervals (CI) throughout the tasks. The results showed that the depth of the squat and split squat were unaffected by the changed environment while water immersion allowed for a deeper single leg squat. The different environments had significant effects on the sagittal plane orientations and speeds for all segments. Water immersion increased the degree of movement variability of the segments in all exercises, except for the shank in the frontal plane, which showed more variability on land. Without compromising movement depth, the aquatic environment induces more upright trunk and shank postures during squats and split squats. The aquatic environment allows for increased squat depth during the single-leg squat, and increased shank motions in the frontal plane. Our observations therefore support the use of water-based squat tasks for rehabilitation as they appear to

  4. Kinematic Precise Point Positioning Using Multi-Constellation Global Navigation Satellite System (GNSS Observations

    Directory of Open Access Journals (Sweden)

    Xidong Yu

    2017-01-01

    Full Text Available Multi-constellation global navigation satellite systems (GNSSs are expected to enhance the capability of precise point positioning (PPP by improving the positioning accuracy and reducing the convergence time because more satellites will be available. This paper discusses the performance of multi-constellation kinematic PPP based on a multi-constellation kinematic PPP model, Kalman filter and stochastic models. The experimental dataset was collected from the receivers on a vehicle and processed using self-developed software. A comparison of the multi-constellation kinematic PPP and real-time kinematic (RTK results revealed that the availability, positioning accuracy and convergence performance of the multi-constellation kinematic PPP were all better than those of both global positioning system (GPS-based PPP and dual-constellation PPP. Multi-constellation kinematic PPP can provide a positioning service with centimetre-level accuracy for dynamic users.

  5. Exploring the Origin of Kinematically Irregular Galaxies with MaNGA

    Science.gov (United States)

    Stark, David Vincent; Bundy, Kevin; Westfall, Kyle; Bershady, Matthew; Cheung, Edmond; Soler, Juan; Brinchmann, Jarle; Abraham, Roberto; Bizyaev, Dmitry; Masters, Karen; Weijmans, Anne-Marie; Chen, Yanmei; Jin, Yifei; Drory, Niv; Lopes, Alexandre Roman; Law, David

    2018-01-01

    Deviations from normal rotation in galaxies may have a number of potential drivers, including tidal interactions, gas inflows/outflows, spiral structure, bar/oval distortions, or other internally generated instabilities. Thanks to new massive IFU surveys like MaNGA, we can now characterize the gas and stellar kinematics of thousands of galaxies in the local universe, enabling statistical analyses on the frequency of disturbed kinematics, their origin, and their impact on their host galaxies. We present a census of kinematics in MaNGA using a modified version of the Radon transform to map radial variations in kinematic position angles (PA). We discuss the frequency of kinematically irregular disks, and describe commonly observed patterns in radial PA profiles. In order to constrain the drivers of these kinematic signatures, we analyze how they correlate with galaxy mass, environment, star formation history, and gas-phase metallicity.

  6. Dynamic Modelling of Tooth Deformation Using Occlusal Kinematics and Finite Element Analysis.

    Directory of Open Access Journals (Sweden)

    Stefano Benazzi

    Full Text Available Dental biomechanics based on finite element (FE analysis is attracting enormous interest in dentistry, biology, anthropology and palaeontology. Nonetheless, several shortcomings in FE modeling exist, mainly due to unrealistic loading conditions. In this contribution we used kinematics information recorded in a virtual environment derived from occlusal contact detection between high resolution models of an upper and lower human first molar pair (M1 and M1, respectively to run a non-linear dynamic FE crash colliding test.MicroCT image data of a modern human skull were segmented to reconstruct digital models of the antagonistic right M1 and M1 and the dental supporting structures. We used the Occlusal Fingerprint Analyser software to reconstruct the individual occlusal pathway trajectory during the power stroke of the chewing cycle, which was applied in a FE simulation to guide the M1 3D-path for the crash colliding test.FE analysis results showed that the stress pattern changes considerably during the power stroke, demonstrating that knowledge about chewing kinematics in conjunction with a morphologically detailed FE model is crucial for understanding tooth form and function under physiological conditions.Results from such advanced dynamic approaches will be applicable to evaluate and avoid mechanical failure in prosthodontics/endodontic treatments, and to test material behavior for modern tooth restoration in dentistry. This approach will also allow us to improve our knowledge in chewing-related biomechanics for functional diagnosis and therapy, and it will help paleoanthropologists to illuminate dental adaptive processes and morphological modifications in human evolution.

  7. Kinematic vorticity number – a tool for estimating vortex sizes and circulations

    Directory of Open Access Journals (Sweden)

    Lisa Schielicke

    2016-02-01

    Full Text Available The influence of extratropical vortices on a global scale is mainly characterised by their size and by the magnitude of their circulation. However, the determination of these properties is still a great challenge since a vortex has no clear delimitations but is part of the flow field itself. In this work, we introduce a kinematic vortex size determination method based on the kinematic vorticity number Wk to atmospheric flows. Wk relates the local rate-of-rotation to the local rate-of-deformation at every point in the field and a vortex core is identified as a simply connected region where the rotation prevails over the deformation. Additionally, considering the sign of vorticity in the extended Wk-method allows to identify highs and lows in different vertical layers of the atmosphere and to study vertical as well as horizontal vortex interactions. We will test the Wk-method in different idealised -D (superposition of two lows/low and jet and real -D flow situations (winter storm affecting Europe and compare the results with traditional methods based on the pressure and the vorticity fields. In comparison to these traditional methods, the Wk-method is able to extract vortex core sizes even in shear-dominated regions that occur frequently in the upper troposphere. Furthermore, statistics of the size and circulation distributions of cyclones will be given. Since the Wk-method identifies vortex cores, the identified radii are subsynoptic with a broad peak around 300–500 km at the 1000 hPa level. However, the total circulating area is not only restricted to the core. In general, circulations are in the order of 107 m2/s with only a few cyclones in the order of 108 m2/s.

  8. Muscle activity influence on the kinematics of the cervical spine in frontal tests.

    Science.gov (United States)

    Dehner, Christoph; Schick, Sylvia; Kraus, Michael; Scola, Alexander; Hell, Wolfram; Kramer, Michael

    2013-01-01

    The question of muscle activity influence on the cervical spine kinematics during rear-end and frontal crash events has been discussed. Less data are available concerning frontal collisions. Therefore, the objective of this study was to investigate the influence of the ventral and dorsal neck muscles on the cervical spine kinematics during simulated frontal sled collisions. A frontal collision with a velocity change (delta V) of 10.2 km/h was simulated in a sled test with 10 healthy subjects (7 female; 3 male). A high-speed camera and accelerometers recorded the motion and acceleration data. The activity of the sternocleidomastoid muscles was recorded with surface electrodes. To avoid cross-talk, an intramuscular recording of the semispinalis capitis muscles was performed with fine-wire electrodes. The sequence of both muscle activities was reproducible in all subjects. The maximal force of the sternocleidomastoid muscle was observed after a median of 152 ms, with 0 defining the time of the trigger signal. With earlier onset of muscle force, maximal dorsal horizontal acceleration of the head (r = -0.600) was reached later and the ventral translation (r = -0.733) and flexion movement (r = -0.755) set in earlier. The maximal force of the semispinalis capitis muscle was observed after a median of 160 ms. If the duration of muscle force was longer, the maximal head flexion (r = 0.685) and the maximal ventral head translation (r = 0.738) were reached later. The sternocleidomastoid muscle force is mainly associated with the horizontal head acceleration and influences the onset of the flexion and translation motion. To summarize, these temporal correlations allow the conclusion that the semispinalis capitis muscle force is mainly associated with the angular head acceleration and influences the duration of the flexion and translation motion.

  9. A Kinematic Calibration Process for Flight Robotic Arms

    Science.gov (United States)

    Collins, Curtis L.; Robinson, Matthew L.

    2013-01-01

    The Mars Science Laboratory (MSL) robotic arm is ten times more massive than any Mars robotic arm before it, yet with similar accuracy and repeatability positioning requirements. In order to assess and validate these requirements, a higher-fidelity model and calibration processes were needed. Kinematic calibration of robotic arms is a common and necessary process to ensure good positioning performance. Most methodologies assume a rigid arm, high-accuracy data collection, and some kind of optimization of kinematic parameters. A new detailed kinematic and deflection model of the MSL robotic arm was formulated in the design phase and used to update the initial positioning and orientation accuracy and repeatability requirements. This model included a higher-fidelity link stiffness matrix representation, as well as a link level thermal expansion model. In addition, it included an actuator backlash model. Analytical results highlighted the sensitivity of the arm accuracy to its joint initialization methodology. Because of this, a new technique for initializing the arm joint encoders through hardstop calibration was developed. This involved selecting arm configurations to use in Earth-based hardstop calibration that had corresponding configurations on Mars with the same joint torque to ensure repeatability in the different gravity environment. The process used to collect calibration data for the arm included the use of multiple weight stand-in turrets with enough metrology targets to reconstruct the full six-degree-of-freedom location of the rover and tool frames. The follow-on data processing of the metrology data utilized a standard differential formulation and linear parameter optimization technique.

  10. Phalangeal joints kinematics during ostrich (Struthio camelus locomotion

    Directory of Open Access Journals (Sweden)

    Rui Zhang

    2017-01-01

    Full Text Available The ostrich is a highly cursorial bipedal land animal with a permanently elevated metatarsophalangeal joint supported by only two toes. Although locomotor kinematics in walking and running ostriches have been examined, these studies have been largely limited to above the metatarsophalangeal joint. In this study, kinematic data of all major toe joints were collected from gaits with double support (slow walking to running during stance period in a semi-natural setup with two selected cooperative ostriches. Statistical analyses were conducted to investigate the effect of locomotor gait on toe joint kinematics. The MTP3 and MTP4 joints exhibit the largest range of motion whereas the first phalangeal joint of the 4th toe shows the largest motion variability. The interphalangeal joints of the 3rd and 4th toes present very similar motion patterns over stance phases of slow walking and running. However, the motion patterns of the MTP3 and MTP4 joints and the vertical displacement of the metatarsophalangeal joint are significantly different during running and slow walking. Because of the biomechanical requirements, osctriches are likely to select the inverted pendulum gait at low speeds and the bouncing gait at high speeds to improve movement performance and energy economy. Interestingly, the motions of the MTP3 and MTP4 joints are highly synchronized from slow to fast locomotion. This strongly suggests that the 3rd and 4th toes really work as an “integrated system” with the 3rd toe as the main load bearing element whilst the 4th toe as the complementary load sharing element with a primary role to ensure the lateral stability of the permanently elevated metatarsophalangeal joint.

  11. Galactic masers: Kinematics, spiral structure and the disk dynamic state

    Science.gov (United States)

    Rastorguev, A. S.; Utkin, N. D.; Zabolotskikh, M. V.; Dambis, A. K.; Bajkova, A. T.; Bobylev, V. V.

    2017-04-01

    We applied the currently most comprehensive version of the statistical-parallax technique to derive kinematical parameters of the maser sample with 136 sources. Our kinematic model comprises the overall rotation of the Galactic disk and the spiral density-wave effects. We take into account the variation of radial velocity dispersion with Galactocentric distance. The best description of the velocity field is provided by the model with constant radial and vertical velocity dispersions, $(\\sigma U0, \\sigma W0) \\approx (9.4 \\pm 0.9~, 5.9 \\pm 0.8)~ km/s$. We compute flat Galactic rotation curve over the Galactocentric distance interval from 3 to 15 kpc and find the local circular rotation velocity to be $ V_0 \\approx (235-238)$~ km/s $\\pm 7$~ km/s. We also determine the parameters of the four-armed spiral pattern (pitch angle $i \\approx (-10.4 \\pm 0.3)^\\circ$ and the phase of the Sun $\\chi_0 \\approx (125 \\pm 10) ^\\circ$). The radial and tangential spiral perturbations are about $f_R \\approx (-6.9 \\pm 1.4)$~km/s, $f_\\Theta \\approx (+2.8 \\pm 1.0$) ~km/s. The kinematic data yield a solar Galactocentric distance of $R_0 \\approx (8.24 \\pm 0.12)~kpc$. Based on rotation curve parameters and the asymmetric drift we Infer the exponential disk scale $H_D \\approx (2.7 \\pm 0.2)$ ~kpc under assumption of marginal stability of the intermediate-age disk, and finally we estimate the minimum local surface disk density, $\\Sigma (R_0) > (26 \\pm 3) ~ M_\\odot pc^{-2}$.

  12. Kinematic classification of non-interacting spiral galaxies

    Science.gov (United States)

    Wiegert, Theresa; English, Jayanne

    2014-01-01

    Using neutral hydrogen (HI) rotation curves of 79 galaxies, culled from the literature, as well as measured from HI data, we present a method for classifying disk galaxies by their kinematics. In order to investigate fundamental kinematic properties we concentrate on non-interacting spiral galaxies. We employ a simple parameterized form for the rotation curve in order to derive the three parameters: the maximum rotational velocity, the turnover radius and a measure of the slope of the rotation curve beyond the turnover radius. Our approach uses the statistical Hierarchical Clustering method to guide our division of the resultant 3D distribution of galaxies into five classes. Comparing the kinematic classes in this preliminary classification scheme to a number of galaxy properties, we find that our class containing galaxies with the largest rotational velocities has a mean morphological type of Sb/Sbc while the other classes tend to later types. Other trends also generally agree with those described by previous researchers. In particular we confirm correlations between increasing maximum rotational velocity and the following observed properties: increasing brightness in B-band, increasing size of the optical disk (D25) and increasing star formation rate (as derived using radio continuum data). Our analysis also suggests that lower velocities are associated with a higher ratio of the HI mass over the dynamical mass. Additionally, three galaxies exhibit a drop in rotational velocity amplitude of ≳20% after the turnover radius. However recent investigations suggest that they have interacted with minor companions which is a common cause for declining rotation curves.

  13. Generic robotic kinematic generator for virtual environment interfaces

    Science.gov (United States)

    Flueckiger, Lorenzo; Piguet, Laurent; Baur, Charles

    1996-12-01

    The expansion of robotic systems' performance, as well as the need for such machines to work in complex environments (hazardous, small, distant, etc.), involves the need for user interfaces which permit efficient teleoperation. Virtual Reality based interfaces provide the user with a new method for robot task planning and control: he or she can define tasks in a very intuitive way by interacting with a 3D computer generated representation of the world, which is continuously updated thanks to multiple sensors fusion and analysis. The Swiss Federal Institute of Technology has successfully tested different kinds of teleoperations. In the early 90s, a transatlantic teleoperation of a conventional robot manipulator with a vision feedback system to update the virtual world was achieved. This approach was then extended to perform teleoperation of several mobile robots (Khepera, Koala) as well as to control microrobots used for microsystems' assembly in the micrometer range. One of the problems encountered with such an approach is the necessity to program a specific kinematic algorithm for each kind of manipulator. To provide a more general solution, we started a project aiming at the design of a 'kinematic generator' (CINEGEN) for the simulation of generic serial and parallel mechanical chains. With CINEGEN, each manipulator is defined with an ascii file description and its attached graphics files; inserting a new manipulator simply requires a new description file, and none of the existing tools require modification. To have a real time behavior, we have chosen a numerical method based on the pseudo-Jacobian method to generate the inverse kinematics of the robot. The results obtained with an object-oriented implementation on a graphic workstation are presented in this paper.

  14. Kinematic Origins of Motor Inconsistency in Expert Pianists.

    Directory of Open Access Journals (Sweden)

    Kenta Tominaga

    Full Text Available For top performers, including athletes and musicians, even subtle inconsistencies in rhythm and force during movement production decrease the quality of performance. However, extensive training over many years beginning in childhood is unable to perfect dexterous motor performance so that it is without any error. To gain insight into the biological mechanisms underlying the subtle defects of motor actions, the present study sought to identify the kinematic origins of inconsistency of dexterous finger movements in musical performance. Seven highly-skilled pianists who have won prizes at international piano competitions played a short sequence of tones with the right hand at a predetermined tempo. Time-varying joint angles of the fingers were recorded using a custom-made data glove, and the timing and velocity of the individual keystrokes were recorded from a digital piano. Both ridge and stepwise multiple regression analyses demonstrated an association of the inter-trial variability of the inter-keystroke interval (i.e., rhythmic inconsistency with both the rotational velocity of joints of the finger used for a keystroke (i.e., striking finger and the movement independence between the striking and non-striking fingers. This indicates a relationship between rhythmic inconsistency in musical performance and the dynamic features of movements in not only the striking finger but also the non-striking fingers. In contrast, the inter-trial variability of the key-descending velocity (i.e., loudness inconsistency was associated mostly with the kinematic features of the striking finger at the moment of the keystroke. Furthermore, there was no correlation between the rhythmic and loudness inconsistencies. The results suggest distinct kinematic origins of inconsistencies in rhythm and loudness in expert musical performance.

  15. Kinematic Origins of Motor Inconsistency in Expert Pianists.

    Science.gov (United States)

    Tominaga, Kenta; Lee, André; Altenmüller, Eckart; Miyazaki, Fumio; Furuya, Shinichi

    2016-01-01

    For top performers, including athletes and musicians, even subtle inconsistencies in rhythm and force during movement production decrease the quality of performance. However, extensive training over many years beginning in childhood is unable to perfect dexterous motor performance so that it is without any error. To gain insight into the biological mechanisms underlying the subtle defects of motor actions, the present study sought to identify the kinematic origins of inconsistency of dexterous finger movements in musical performance. Seven highly-skilled pianists who have won prizes at international piano competitions played a short sequence of tones with the right hand at a predetermined tempo. Time-varying joint angles of the fingers were recorded using a custom-made data glove, and the timing and velocity of the individual keystrokes were recorded from a digital piano. Both ridge and stepwise multiple regression analyses demonstrated an association of the inter-trial variability of the inter-keystroke interval (i.e., rhythmic inconsistency) with both the rotational velocity of joints of the finger used for a keystroke (i.e., striking finger) and the movement independence between the striking and non-striking fingers. This indicates a relationship between rhythmic inconsistency in musical performance and the dynamic features of movements in not only the striking finger but also the non-striking fingers. In contrast, the inter-trial variability of the key-descending velocity (i.e., loudness inconsistency) was associated mostly with the kinematic features of the striking finger at the moment of the keystroke. Furthermore, there was no correlation between the rhythmic and loudness inconsistencies. The results suggest distinct kinematic origins of inconsistencies in rhythm and loudness in expert musical performance.

  16. Multiobjective Optimum Design of a 3-RRR Spherical Parallel Manipulator with Kinematic and Dynamic Dexterities

    DEFF Research Database (Denmark)

    Wu, Guanglei

    2012-01-01

    This paper deals with the kinematic synthesis problem of a 3-RRR spherical parallel manipulator, based on the evaluation criteria of the kinematic, kinetostatic and dynamic performances of the manipulator. A multiobjective optimization problem is formulated to optimize the structural and geometric...... parameters of the spherical parallel manipulator. The proposed approach is illustrated with the optimum design of a special spherical parallel manipulator with unlimited rolling motion. The corresponding optimization problem aims to maximize the kinematic and dynamic dexterities over its regular shaped...

  17. On The Dynamics And Kinematics Of Two Fluid Phase Flow In Porous Media

    Science.gov (United States)

    2015-06-16

    SECURITY CLASSIFICATION OF: A model formulated in terms of both conservation and kinematic equations for phases and interfaces in two- fuid - phase flow in a...terms of both conservation and kinematic equations for phases and interfaces in two- fuid - phase flow in a porous medium system is summarized...principles. Models based on both conservation and kinematic equations can describe multiphase flow with varying fidelity. When only phase-based equa

  18. Digital Hardware Realization of Forward and Inverse Kinematics for a Five-Axis Articulated Robot Arm

    OpenAIRE

    Hai Linh, Bui Thi; Kung, Ying-Shieh

    2015-01-01

    When robot arm performs a motion control, it needs to calculate a complicated algorithm of forward and inverse kinematics which consumes much CPU time and certainty slows down the motion speed of robot arm. Therefore, to solve this issue, the development of a hardware realization of forward and inverse kinematics for an articulated robot arm is investigated. In this paper, the formulation of the forward and inverse kinematics for a five-axis articulated robot arm is derived firstly. Then, the...

  19. Kinematic Analysis of 2-DOF Planer Robot Using Artificial Neural Network

    OpenAIRE

    Jolly Shah; S.S.Rattan; B.C.Nakra

    2011-01-01

    Automatic control of the robotic manipulator involves study of kinematics and dynamics as a major issue. This paper involves the forward and inverse kinematics of 2-DOF robotic manipulator with revolute joints. In this study the Denavit- Hartenberg (D-H) model is used to model robot links and joints. Also forward and inverse kinematics solution has been achieved using Artificial Neural Networks for 2-DOF robotic manipulator. It shows that by using artificial neural networ...

  20. Nonpartonic Effects in Pion Electroproduction in the Hermes Kinematical Region

    International Nuclear Information System (INIS)

    Uleshchenko, V.; Szczurek, A.

    2002-01-01

    The presentation is concerned with higher twist corrections of nonpartonic origin to semi-inclusive observables in the kinematical region relevant for the HERMES experiment. We demonstrate a strong impact of the VDM-like interaction and the exclusive production of ρ 0 meson on the extraction of the (anti)d - (anti)u asymmetry from charged pion DIS multiplicities. We also show that it is the exclusive- ρ 0 channel which accounts for the experimentally observed effect of the excess of charged over neutral pions produced at large z. (author)