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Artykuły w czasopismach na temat "Rolling body problem"
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Alouges, François, Yacine Chitour i Ruixing Long. "A Motion-Planning Algorithm for the Rolling-Body Problem". IEEE Transactions on Robotics 26, nr 5 (październik 2010): 827–36. http://dx.doi.org/10.1109/tro.2010.2053733.
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Chitour, Y., A. Marigo i B. Piccoli. "Quantization of the rolling-body problem with applications to motion planning". Systems & Control Letters 54, nr 10 (październik 2005): 999–1013. http://dx.doi.org/10.1016/j.sysconle.2005.02.012.
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Miftakhova, Almira, Yang-Yuan Chen i Jeng-Haur Horng. "Effect of rolling on the friction coefficient in three-body contact". Advances in Mechanical Engineering 11, nr 8 (sierpień 2019): 168781401987230. http://dx.doi.org/10.1177/1687814019872303.
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The contact problem of system of particles rolling over a viscoelastic layer bonded to the rigid half-space was considered. Particles have a spherical shape and their radiuses are distributed along Gauss. Earlier, the friction coefficient was obtained for the particles between surfaces in the relative movement of the surfaces using the three-body interaction method. In this study, the contact area was calculated for a system of particles rolling over the viscoelastic layer bonded to the half-space. Using the three-body interaction approach, the friction coefficient was calculated, taking into account the rolling of particles. The results demonstrate that the coefficient of friction, calculated using the three-body model, decreases when the rolling of particles is taken into account.
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Kennedy, Kevin F. "An Approximate Three-Dimensional Metal Flow Analysis for Shape Rolling". Journal of Engineering for Industry 110, nr 3 (1.08.1988): 223–31. http://dx.doi.org/10.1115/1.3187873.
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An approximate three-dimensional metal flow analysis for shape rolling is developed. The analysis, which is presently applicable to rod rolling, is based on an upper-bound approach in which an iterative numerical procedure is used to minimize the energy dissipation rate to obtain kinematically admissible velocity field solutions of the rolling problem. Once the velocity field and the final shape of the plastically deforming body are known, then elementary stress analysis techniques are used to determine the force related aspects of the rolling problem. It is assumed that the rolled material is rigid perfectly plastic, and only the purely mechanical aspects of the metal deformation problem in rolling are considered assuming isothermal conditions. The analysis shows good agreement with elongation and roll separating force measurements in the hot rolling of mild carbon steel for a variety of workpiece and roll cross-section geometries commonly used in rod rolling.
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Kennedy, K. F. "A Method for Analyzing Spread, Elongation and Bulge in Flat Rolling". Journal of Engineering for Industry 109, nr 3 (1.08.1987): 248–56. http://dx.doi.org/10.1115/1.3187126.
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A method for analyzing spread, elongation, and bulge in flat rolling is developed. The analysis is based on an upper-bound approach in which an iterative numerical procedure is used to minimize the energy dissipation rate for kinematically admissible velocity field solutions for the rolling problem. Once the velocity field and the final shape of the plastically deforming body are known, then elementary stress analysis techniques are used to determine the force related aspects of the rolling problem. It is assumed that the rolled material is rigid perfectly plastic, and only the purely mechanical aspects of the metal deformation problem in rolling are considered, assuming isothermal conditions. The analysis shows good agreement with spread, elongation, roll separating force, and roll torque measurements in the hot rolling of mild carbon steel. Discussion of the factors which lead to single-bulge or double-bulge deformation in flat rolling, and a suggested technique for estimating the interface friction conditions in rolling, the Flat Bar Test, are also included.
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Moghadasi, S. Reza. "Rolling of a body on a plane or a sphere: a geometric point of view". Bulletin of the Australian Mathematical Society 70, nr 2 (październik 2004): 245–56. http://dx.doi.org/10.1017/s0004972700034468.
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A pair of bodies rolling on each other is an interesting example of nonholonomic systems in control theory. Here the controllability of rolling bodies is investigated with a global approach. By using simple geometric facts, this problem has been completely solved in the special case where one of them is a plane or a sphere.
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Chepchurov, Mihail, Alexander Sumskoy, Julia Zhigulina i Denis Podpryatov. "Distortion identification of the cylindrical part form of technological units". Automation and modeling in design and management 2022, nr 4 (21.12.2022): 29–36. http://dx.doi.org/10.30987/2658-6436-2022-4-29-36.
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The paper deals with the issues arising during the technological unit operation, in particular, the geometric characteristics control of large parts of the units. The main types of rolling the surface wear of cylindrical elements of various technological equipment are given (according to GOST 24642-81, GOST 18322-2016). The equipment wear patterns due to the operating conditions and the unit design, as well as differences in the part shape distortion with the roundness loss are highlighted. It is revealed that the uneven wear of the rolling surface of the technological cylindrical parts causes shape distortion. Considering this, the profile of a conditional round part in cross section relative to one centre is modelled. The appearance of ovality is accepted as the main defect of cylindrical parts. A calculation scheme is presented for constructing the distortion of the cylindrical body profile located on two round supports. An algorithm for computing the radii centre displacement is presented. Theoretical calculations and the algorithm are confirmed by a virtual kinematic model that displays rolling a non-circular body on two idlers. The method described in the paper for obtaining a visual kinematic model, based on an analytical description of rolling a non-circular body, is proposed to be used as a direct problem of searching for instantaneous centres of rotation. The kinematic model obtained by solving the direct problem can be applied for training a neural network that processes the measurement results of a real rolling body
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Sönmez, Murat. "A Study on the Combined Effect of Axle Friction and Rolling Resistance". International Journal of Mechanical Engineering Education 31, nr 2 (kwiecień 2003): 101–7. http://dx.doi.org/10.7227/ijmee.31.2.2.
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Many textbooks on mechanics for engineering students and engineers consider the concepts of rolling resistance and axle friction separately, expecting readers to combine the given analysis for each of them in determining, for instance, the magnitude of the force needed to move a railroad car. However, this requires a thorough free-body diagram analysis and, since examples are not typically included in the textbooks, students may have difficulty solving such problems. This study represents the solution of the problem in terms of both the dry axle friction and the rolling resistance. It is also suggested as a good synthesis problem that may be considered in teaching the effect of dry friction to engineering students.
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Spector, A. A., i R. C. Batra. "Rolling/Sliding of a Vibrating Elastic Body on an Elastic Substrate". Journal of Tribology 118, nr 1 (1.01.1996): 147–52. http://dx.doi.org/10.1115/1.2837070.
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The rolling/sliding in the presence of friction of a vibrating elastic body on an elastic substrate is studied. It is shown that the longitudinal components of the velocity of the center of mass of the body and of the resultant frictional force are not affected by the vibration process. However, the normal vibration of the body influences the slip velocities and the distribution of frictional forces. For the problem of a harmonically oscillating long cylinder rolling/sliding on the flat surface of an elastic substrate, the time histories of the width of the contact zone and the length of adhesion subzone are computed. It is shown that the local frictional forces and slip velocities oscillate, and that the set of admissible values of the external frictional forces and moments providing the rolling/sliding regime is smaller under conditions of normal vibrations than that when the cylinder does not vibrate.
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Spector, A., i R. C. Batra. "On the Motion of an Elastic Body Rolling/Sliding on an Elastic Substrate". Journal of Tribology 117, nr 2 (1.04.1995): 308–14. http://dx.doi.org/10.1115/1.2831248.
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The three-dimensional evolutionary problem of rolling/sliding of a linear elastic body on a linear elastic substrate is studied. The inertial properties of the body regarded as rigid are accounted for. By employing an asymptotic analysis, it is shown that the process can be divided into two phases: transient and quasistationary. An expression for the frictional force as a function of the externally applied forces and moments, and inertial properties of the body is derived. For an ellipsoid rolling/sliding on a linear elastic substrate, numerical results for the frictional force distribution, slip/adhesion subareas, and the evolution of the slip velocity are given.
Rozprawy doktorskie na temat "Rolling body problem"
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Manríquez, Peñafiel Ronald. "Local approximation by linear systems and Almost-Riemannian Structures on Lie groups and Continuation method in rolling problem with obstacles". Electronic Thesis or Diss., université Paris-Saclay, 2022. https://theses.hal.science/tel-03716186.
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L'objectif de cette thèse est d'étudier deux sujets en géométrie sub-Riemannienne. D'une part, l'approximation locale d'une structure presque riemannienne aux points singuliers, et d'autre part, le système cinématique d’une variété à 2 dimensions roulant (sans torsion ni glissement) sur le plan euclidien avec des régions interdites. Une structure presque riemannienne de dimension n peut être définie localement par n champs vectoriels satisfaisant la condition de rang de l'algèbre de Lie, jouant le rôle d'un cadre orthonormé. L'ensemble des points où ces champs vectoriels sont colinéaires est appelé l'ensemble singulier Z. Aux points de tangence, c'est-à-dire aux points où l'espace linéaire engendré par champs vectoriels est égale à l'espace tangent de Z, l'approximation nilpotente peut être remplacée par l'approximation solvable. Dans cette thèse, sous des conditions génériques, nous établissons l'ordre d'approximation de la distance originale par d ̃ (la distance induite par l'approximation solvable) et nous prouvons que d ̃ est plus proche que la distance induite par l'approximation nilpotente de la distance originale. En ce qui concerne les structures des systèmes d'approximation, l'algèbre de Lie générée par cette nouvelle famille de champs vectoriels est de dimension finie et solvable (dans le cas générique). De plus, l'approximation solvable est équivalente à un ARS linéaire sur un espace homogène ou un groupe de Lie. D'autre part, les systèmes non-holonomes ont attiré l'attention de nombreux auteurs de différentes disciplines pour leurs applications variées, principalement en robotique. Le problème du corps roulant (sans glissement ni rotation) d'une variété riemannien bidimensionnel sur une autre variété peut être écrit comme un système non-holonomique. De nombreuses méthodes, algorithmes et techniques ont été développés pour le résoudre. Une implémentation numérique de la méthode de continuation pour résoudre le problème dans lequel une surface convexe roule sur le plan euclidien avec des régions interdites (ou obstacles) sans glisser ou tourner est effectuée. Plusieurs exemples sont illustrésThe aim of this thesis is to study two topics in sub-Riemannian geometry. On the one hand, the local approximation of an almost-Riemannian structure at singular points, and on the other hand, the kinematic system of a 2-dimensional manifold rolling (without twisting or slipping) on the Euclidean plane with forbidden regions. A n-dimensional almost-Riemannian structure can be defined locally by n vector fields satisfying the Lie algebra rank condition, playing the role of an orthonormal frame. The set of points where these vector fields are colinear is called the singular set (Z). At tangency points, i.e., points where the linear span of the vector fields is equal to the tangent space of Z, the nilpotent approximation can be replaced by the solvable one. In this thesis, under generic conditions, we state the order of approximation of the original distance by d ̃ (the distance induced by the solvable approximation), and we prove that d ̃ is closer than the distance induced by the nilpotent approximation to the original distance. Regarding the structure of the approximating system, the Lie algebra generated by this new family of vector fields is finite-dimensional and solvable (in the generic case). Moreover, the solvable approximation is equivalent to a linear ARS on a homogeneous space or a Lie group. On the other hand, nonholonomic systems have attracted the attention of many authors from different disciplines for their varied applications, mainly in robotics. The rolling-body problem (without slipping or spinning) of a 2-dimensional Riemannian manifold on another one can be written as a nonholonomic system. Many methods, algorithms, and techniques have been developed to solve it. A numerical implementation of the Continuation Method to solve the problem in which a convex surface rolls on the Euclidean plane with forbidden regions (or obstacles) without slipping or spinning is performed. Several examples are illustrated
Części książek na temat "Rolling body problem"
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Hill, R. "Two-Dimensional Problems Of Steady Motion". W The Mathematical Theory Of Plasticity, 161–212. Oxford University PressOxford, 1998. http://dx.doi.org/10.1093/oso/9780198503675.003.0007.
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Abstract In this and the two following chapters the ideas and techniques of Chapter VI a.re applied to the solution of a variety of problems of plane strain. We begin with problems of steady motion, in which the stress and velocitydo not vary at anyfixed point (referred to some coordinate system which may be at rest or moving uniformly). This condition is fulfilled in continuous processes of shaping metals, for example rolling, drawing, and extrusion. The approximation by the plastic-rigid body is likely to be good since the strains are usually large; the error due to the neglect of work-hardening can be largely removed by a simple correction factor, as we shall see. While the two-dimensional theory is strictly valid only for wide blocks or sheets, as in strip-rolling, it gives a useful qualitative picture of the deformation in such processes as the drawing of wire or the extrusion of rod; it will be shown, too, that the theoretical results, suitably modified, frequently provide a. close estimate of the energy consumption.
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Kobayashi, Shiro, Soo-Ik Oh i Taylan Altan. "Preform Design in Metal Forming". W Metal Forming and the Finite-Element Method. Oxford University Press, 1989. http://dx.doi.org/10.1093/oso/9780195044027.003.0018.
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Preform design in metal forming refers to the design of an initial shape of the workpiece that, when it has undergone an associated forming process, forms the required product shape with desired property successfully without formation of defects and without excessive waste of materials. A carefully selected preform can contribute significantly to the reduction of the production costs. Preform design problems are encountered in various metal-forming processes, such as closed-die forging, shell nosing, rolling, and sheet-metal forming. Design of an optimal preform shape requires simultaneous determination of optimal process conditions. However, we are here concerned with the determination of the best preform shape under a given set of process conditions. In this chapter, a new method of “backward tracing” is introduced as an alternative approach to the solution of preform design, and the applications of this method to some specific processes are discussed. Similarly to the forward simulation technique, the backward tracing method uses the finite-element method. The forward simulation technique has been discussed in the previous chapters. Backward tracing refers to the prediction of the part configuration at any stage in a deformation process, when the final part geometry and process conditions are given. The concept is illustrated in Fig. 15.1. At time t = t0, the geometrical configuration x0 of a deforming body is represented by a point Q. The point Q is arrived at from the point P, whose configuration is given as x0–1 at t = t0–1, through the displacement field during a time-step Δt, namely, x0 = x0–1 + u0–1 Δt, where u0–1 is the velocity field at t = t0–1. Therefore, the problem is to determine u0–1, based on the information (x0) at point Q. The solution scheme is as follows: taking a loading solution u0 (forward) at Q, a first estimate of P can be made according to P(1) = x0 – u0 Δt.
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Chambers, Marcie L., John K. Hewitt, Stephanie Schmitz, Robin P. Corley i David W. Fulker. "Height, Weight, and Body Mass Index". W Infancy to Early Childhood, 292–306. Oxford University PressNew York, NY, 2001. http://dx.doi.org/10.1093/oso/9780195130126.003.0022.
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Abstract Being overweight or obese is a health problem of increasing concern in indus trialized societies. The prevalence of being overweight in the United States appears to be rising both in adults (Kuczmarski et al., 1994) and in children (Gortmaker et al., 1987). Obesity in childhood is predictive of obesity in adult hood (Rolland-Cachera et al., 1987), and being overweight or obese is related to morbidity for a variety of diseases, including non-insulin-dependent diabetes, hypertension, and coronary heart disease (Hubert et al., 1983; Pi-Sunyer, 1991; Van Hallie, 1985;) as well as being associated with reduced longevity (Lew, 1985; Lew and Garfinkel, 1979).
Streszczenia konferencji na temat "Rolling body problem"
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Alouges, Francois, Yacine Chitour i Ruixing Long. "A motion planning algorithm for the rolling-body problem". W 2009 Joint 48th IEEE Conference on Decision and Control (CDC) and 28th Chinese Control Conference (CCC 2009). IEEE, 2009. http://dx.doi.org/10.1109/cdc.2009.5400393.
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Kurasov, Dmitriy. "KINEMATIC POSSIBILITIES OF "GEARED" CLOSED ROLLING BODY SYSTEMS". W PROBLEMS OF APPLIED MECHANICS. Bryansk State Technical University, 2020. http://dx.doi.org/10.30987/conferencearticle_5fd1ed039e5272.57017138.
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In technology, mechanisms are widespread that convert rotary motion into reciprocating or oscillatory. They are most often used in combination with gearboxes. Both of these functions can be performed by one mechanism - an eccentric bearing. The article discusses the problem of studying the kinematic capabilities and rational parametric relationships of various modifications of gear eccentric bearings (EPB).
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Sari, O. Taylan, George G. Adams i Sinan Mu¨ftu¨. "The Sliding and Rolling of a Cylinder at the Nano-Scale". W ASME/STLE 2004 International Joint Tribology Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/trib2004-64347.
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The behavior of a nano-scale cylindrical body (e.g. a fiber), lying on a substrate and acted upon by a combination of normal and tangential forces, is the subject of this investigation. As the scale decreases to the nano level, adhesion becomes an important issue in this contact problem. Thus this investigation treats the two-dimensional plane strain elastic deformation of both the cylinder and the substrate during a rolling/sliding motion, including the effect of adhesion using the Maugis model. For the initiation of sliding, the Mindlin approach is used, whereas for rolling, the Carter approach is utilized. Each case is modified for nano-scale effects by including the effect of adhesion on the contact area and by using the adhesion theory of friction for the friction stress. Analytical results are given for the normal and tangential loading problems, including the initiation of sliding and rolling in terms of dimensionless quantities representing adhesion, cylinder size, and applied forces.
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Rajendran, Suresh, i C. Guedes Soares. "Numerical Investigation of Parametric Rolling of a Container Ship in Regular and Irregular Waves". W ASME 2017 36th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/omae2017-62490.
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Parametric rolling of a post-Panamax C11 class containership in regular and irregular waves is numerically investigated using body nonlinear time domain methods based on strip theory. The Froude-Krylov and the hydrostatic forces are calculated for the exact wetted surface area under the undisturbed incident wave profile. Two kinds of formulations are used for calculation of the radiation forces. The first one employs a linear radiation force in which the frequency dependent hydrodynamic coefficients are calculated for mean position of the sections at mean water level. The second formulation calculates the hydrodynamic coefficients for the exact submerged depth of ship sections under the undisturbed incident wave profile, and hence called as body nonlinear radiation force. The numerical results from the aforementioned formulations are compared with each other, and also with experimental results obtained from a wave tank in both regular and irregular waves. For all the cases in regular waves, the vulnerability to parametric rolling is clearly identified by the numerical models, even though a few discrepancies are observed in the estimation of the severity (maximum roll angle) of the problem. In this paper, the effects of the linear and body nonlinear radiation forces on the numerical calculation of parametric rolling of a container ship and the ability of the numerical methods to identify parametric rolling are investigated.
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Nguyen, Van Duong, Gim Song Soh, Shaohui Foong i Kristin Wood. "Localization of a Miniature Spherical Rolling Robot Using IMU, Odometry and UWB". W ASME 2018 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/detc2018-85548.
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Robots that rolls with a spherical body or spherical robots, exhibits a high degree of mobility and amazing recovery capability from collisions while traversing in the environment. However, the localization of spherical robots in a GPS-denied environment for Intelligent Surveillance and Reconnaissance (ISR) task is a challenging problem due to the complexity of its system dynamics and the limited available sensors technology to sense out of the spherical shell. In our prior work, a kinematic localization technique based on odometry and inertial measurement unit (IMU) sensing was proposed and implemented onto our miniature spherical robot Virgo, for pose estimation. However, it suffers from errors due to slippages during locomotion or as a result of the collision. In this paper, we present a solution to this problem by the inclusion of an additional ultra-wideband (UWB) sensor and fuse it with our kinematic pose estimator using Extended Kalman Filter for indoor localization. Experiments are conducted on a multi-waypoint trajectory to verify its validity and had shown to improve localization performance.
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Cakdi, Sabri, Scott Cummings i John Punwani. "Heavy Haul Coal Car Wheel Load Environment: Rolling Contact Fatigue Investigation". W 2015 Joint Rail Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/jrc2015-5640.
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Railway wheels and rails do not achieve full wear life expectancy due to the combination of wear, plastic deformation, and surface, subsurface, and deep subsurface cracks. Sixty-seven percent of wheel replacement and maintenance in North America is associated with tread damage [1]. Spalling and shelling are the two major types of wheel tread damage observed in railroad operations. Spalling and slid flat defects occur due to skidded or sliding wheels caused by, in general, unreleased brakes. Tread shelling (surface or shallow subsurface fatigue) occurs due to cyclic normal and traction loads that can generate rolling contact fatigue (RCF). Shelling comprises about half of tread damage related wheel replacement and maintenance. The annual problem size associated with wheel tread RCF is estimated to be in the tens of millions of dollars. The total cost includes maintenance, replacement, train delays and fuel consumption. To study the conditions under which RCF damage accumulates, a 36-ton axle load aluminum body coal car was instrumented with a high accuracy instrumented wheelset (IWS), an unmanned data acquisition (UDAC) system, and a GPS receiver. This railcar was sent to coal service between a coal mine and power plant, and traveled approximately 1,300 miles in the fully loaded condition on each trip. Longitudinal, lateral, and vertical wheel-rail forces were recorded continuously during four loaded trips over the same route using the same railcar and instrumentation. The first two trips were conducted with non-steering 3-piece trucks and the last two trips were conducted with passive steering M-976 compliant trucks to allow comparison of the wheel load environment and RCF accumulation between the truck types. RCF initiation predictions were made using “Shakedown Theory” [2]. Conducting two trips with each set of trucks allowed for analysis of the effects of imbalance speed conditions (cant deficiency or excess cant) at some curves on which the operating speeds varied significantly between trips.
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Trinkle, J. C. "Formulation of Multibody Dynamics as Complementarity Problems". W ASME 2003 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/detc2003/vib-48342.
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Multibody systems with rigid bodies and unilateral contacts are difficult to simulate due to discontinuities associated with gaining and losing contacts and stick-slip transitions. Methods for simulating such systems fall into two categories: penalty methods and complementarity methods. The former calculate penetration depths of virtual rigid bodies at every time step and compute restoring forces to repair penetrations, while the latter assume that the bodies are truly rigid and compute contact forces that prevent penetration from occurring at all. In this paper, we are concerned with complementarity methods. We present an instantaneous formulation of the equations of motion of multi-rigid-body systems with frictional contacts as a complementarity problem. The unknowns in this formulation are accelerations and forces at the contacts. Since it is known that this model does not always admit a finite solution, it is problematic to use it directly in an integration scheme. This fact motivates the discrete-time formulation presented second. Although the discrete-time formulation also takes the form of a complementarity problem, it does not suffer from non-existence, and thus it is suitable for simulation. Numerical results are compared to the exact solution for a sphere initially sliding, then rolling, on a horizontal plane.
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Cheung, L. W., K. C. Lau, Flora F. Leung, Donald N. F. Ip, Henry G. H. Chow, Philip W. Y. Chiu i Y. Yam. "Distal Joint Rotation Mechanism for Endoscopic Robot Manipulation". W The Hamlyn Symposium on Medical Robotics: "MedTech Reimagined". The Hamlyn Centre, Imperial College London London, UK, 2022. http://dx.doi.org/10.31256/hsmr2022.74.
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Robot-assisted Minimally Invasive Surgery (MIS) and Natural Orifice Transluminal Endoscopic Surgery (NOTES) are commonly adopted in Gastro-Intestinal (GI) cancer treatment with Endoscopic Submucosal Dissection (ESD). While using fully flexible cable- driven robots brings benefits to patients such as lower rate of complications and shorter healing time, the engineering challenges, for example, size and stiffness, manufacturability and sensorless environment, limit functionalities of robotic instruments and surgery performance. The rolling feature, rotation along the wrist of the instrument, is a good-to-have feature for surgical procedures with orientational and positional requirements such as tractioning and suturing with graspers. In traditional laparoscopy, rolling can be achieved by rotating the long straight rod of the instruments, which is straightforward and effective. However, this is not commonly found in cable-driven endoscopic robotic systems due to mechanical limit for linear-to-rolling motion conversion at distal-end and unmodelled friction resisting torque transmission from proximal-end. Generally, researchers have three approaches to this problem. First, rotate the endoscope or overtube and the instrument together [1] [2]. However, this is not favorable to both surgeon and patient since rotating a twisted endoscope inside a patient’s body requires a large amount of torque and rubbing would create discomfort to the patient. Second, rotate the torque coil or backbone of the instrument [3] [4]. Because friction inside the endoscope is unpredicted and rotation is coupled with roll, pitch, and yaw motion, sophisticated modeling, shape/orientation sensing feedback may be required for robotic automation. Third, develop a distal mechanism to convert cable linear motion into axial rotation [5] [6]. With this method, the coupling problem is solved and power transmission efficiency is improved but a larger and more complicated design is required, and an extra-rigid segment is usually unavoidable. The performance depends greatly on design and implementation. This paper aims to demonstrate a scalable distal joint rotation mechanism for continuum endoscopic robots that can increase instrument dexterity and manipulability to ease the work of surgeons.
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Vantsevich, V. V., A. D. Zakrevskij i S. V. Kharytonchyk. "Heavy-Duty Truck: Inverse Dynamics and Performance Control". W ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-42659.
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Inverse dynamics approach has been developed to optimize a highway, heavy-duty truck vehicle dynamics and performance. Using the developed approach, a math model of the multi-body truck system was developed to optimize power distributions to the drive wheels in probabilistic road conditions including macro- and micro-profiles of the road, distributions of the friction coefficient and rolling resistance. The optimization of wheel power distributions was treated as a multi-criterion problem to provide the truck with required energy/fuel efficiency, traction and velocity operational properties, turnability, stability of motion, and handling. Criteria of the listed truck operational properties were organized in a computer algorithm and computer simulations were implemented. Based on optimal combinations of wheel power distributions, an algorithm for integrated control of driveline power dividing units, wheel brakes and fuel feeding was developed.
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Murakami, Hidenori, i Takeyuki Ono. "A Variational Derivation of Equations of Motion With Contact Constraints Using SE(3)". W ASME 2018 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/imece2018-87126.
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For rigid-body systems subjected to non-holonomic constraints, a streamlined method is presented to derive a minimum number of analytical equations of motion. To illustrate the method, a rolling disk problem is considered. In kinematics, an orthonormal coordinate system is attached to the center of mass together with additional coordinate systems introduced to define the connection path. For each coordinate system, a moving frame is defined by explicitly writing the coordinate vector basis and the position vector of the origin, whereby the attitude of the coordinate vector basis and the coordinates of the origin are compactly stored in a 4 × 4 frame connection matrix of the special Euclidean group, SE(3). Contact velocity constraints are transformed to pfaffians to obtain the associated variational constraints. In kinetics, the principle of virtual work is employed. The desired equations of motion are obtained by expressing the translational and angular velocities at the center of mass as the linear functions of the generalized velocities with the coefficients stored in [B]-matrix, and reducing it to [B*]-matrix after incorporating the contact constraints. The method can be easily extended to multi-body systems with both holonomic and non-holonomic constraints.