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Journal articles on the topic 'Constraint Dynamics'

Author: Grafiati

Published: 4 June 2021

Last updated: 4 February 2022

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1

Wong, R., and D. B. Cherchas. "Hybrid Constraint Space Dynamics and Control for Robot Manipulators." Journal of Vibration and Control 10, no. 11 (2004): 1563–84. http://dx.doi.org/10.1177/1077546304042025.

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In this paper we present the development of a hybrid constraint space dynamics modeling technique and position/force controller for robotic manipulator control in constrained environments. The method utilizes a constraint space dynamic model in which the model coordinates are displacement along the constraint trajectory and the normal force between the manipulator end-effector and the environment. The dynamic model is constructed by transforming the conventional joint space manipulator dynamics equations into their constraint space equivalents through the application of mapping functions, whic

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2

Nair, Manjusha, Jinesh Manchan Kannimoola, Bharat Jayaraman, Bipin Nair, and Shyam Diwakar. "Temporal constrained objects for modelling neuronal dynamics." PeerJ Computer Science 4 (July 23, 2018): e159. http://dx.doi.org/10.7717/peerj-cs.159.

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Background Several new programming languages and technologies have emerged in the past few decades in order to ease the task of modelling complex systems. Modelling the dynamics of complex systems requires various levels of abstractions and reductive measures in representing the underlying behaviour. This also often requires making a trade-off between how realistic a model should be in order to address the scientific questions of interest and the computational tractability of the model. Methods In this paper, we propose a novel programming paradigm, called temporal constrained objects, which f

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3

BATALIN, I. A., and I. V. TYUTIN. "ON THE EQUIVALENCE BETWEEN THE UNIFIED AND STANDARD VERSIONS OF CONSTRAINT DYNAMICS." Modern Physics Letters A 08, no. 39 (1993): 3757–65. http://dx.doi.org/10.1142/s0217732393003494.

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The structure of physical operators and states of the unified constraint dynamics is studied. The genuine second class constraints encoded are shown to be the superselection operators. The unified constrained dynamics is established to be physically-equivalent to the standard BFV-formalism with constraints split.

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4

Wang, J. T. "Inverse Dynamics of Constrained Multibody Systems." Journal of Applied Mechanics 57, no. 3 (1990): 750–57. http://dx.doi.org/10.1115/1.2897087.

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A method for analyzing constrained multibody systems is presented. The method is applicable to a class of problems in which the multibody system is subjected to both force and kinematic constraints. This class of problems cannot be solved by using the classical methods. The method is based upon the concept of partial velocity and generalized forces of Kane’s method to permit the choice of constraint forces for fulfilling both kinematic and force constraints. Thus, the constraint forces or moments at convenient points or bodies may be specified in any desired form. For many applications, the me

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Zurita-Gotor, Pablo, and Geoffrey K. Vallis. "Dynamics of Midlatitude Tropopause Height in an Idealized Model." Journal of the Atmospheric Sciences 68, no. 4 (2011): 823–38. http://dx.doi.org/10.1175/2010jas3631.1.

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Abstract This paper investigates the factors that determine the equilibrium state, and in particular the height and structure of the tropopause, in an idealized primitive equation model forced by Newtonian cooling in which the eddies can determine their own depth. Previous work has suggested that the midlatitude tropopause height may be understood as the intersection between a radiative and a dynamical constraint. The dynamical constraint relates to the lateral transfer of energy, which in midlatitudes is largely effected by baroclinic eddies, and its representation in terms of mean-flow prope

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6

Abramov, N. V., and R. G. Mukharlyamov. "DYNAMICS CONTROL AND CONSTRAINT STABILIZATION." Vestnik of Samara University. Natural Science Series 19, no. 9.1 (2017): 67–75. http://dx.doi.org/10.18287/2541-7525-2013-19-9.1-67-75.

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Results of researchers on dynamics modeling of the systems containing different physical elements are proposed. The construction method of the physical systems dynamics equations, providing constraints stabilization, is discussed. The problem of corresponding constraints reactions or determination of control actions is reduced to the construction of the system of differential equations, assuming that the partial integrals are given. The conditions of asymptotic stability and exponential stability an integral manifold's corresponding constraint equations are defined.

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7

Yang, Xiaohui, Xiaolong Zhang, Shaoping Xu, Yihui Ding, Kun Zhu, and Xiaoping Liu. "An Approach to the Dynamics and Control of Uncertain Robot Manipulators." Algorithms 12, no. 3 (2019): 66. http://dx.doi.org/10.3390/a12030066.

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In this paper, a novel constraint-following control for uncertain robot manipulators that is inspired by analytical dynamics is developed. The motion can be regarded as external constraints of the system. However, it is not easy to obtain explicit equations for dynamic modeling of constrained systems. For a multibody system subject to motion constraints, it is a common practice to introduce Lagrange multipliers, but using these to obtain explicit dynamical equations is a very difficult task. In order to obtain such equations more simply, motion constraints are handled here using the Udwadia-Ka

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8

Cyril, X., J. Angeles, and A. Misra. "DYNAMICS OF FLEXIBLE MULTIBODY MECHANICAL SYSTEMS." Transactions of the Canadian Society for Mechanical Engineering 15, no. 3 (1991): 235–56. http://dx.doi.org/10.1139/tcsme-1991-0014.

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In this paper the formulation and simulation of the dynamical equations of multibody mechanical systems comprising of both rigid and flexible-links are accomplished in two steps: in the first step, each link is considered as an unconstrained body and hence, its Euler-Lagrange (EL) equations are derived disregarding the kinematic couplings; in the second step, the individual-link equations, along with the associated constraint forces, are assembled to obtain the constrained dynamical equations of the multibody system. These constraint forces are then efficiently eliminated by simple matrix mult

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9

Horwitz, L. P., and F. Rohrlich. "Limitations of constraint dynamics." Physical Review D 31, no. 4 (1985): 932–33. http://dx.doi.org/10.1103/physrevd.31.932.

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10

Nikravesh, P. E., O. K. Kwon, and R. A. Wehage. "Euler Parameters in Computational Kinematics and Dynamics. Part 2." Journal of Mechanisms, Transmissions, and Automation in Design 107, no. 3 (1985): 366–69. http://dx.doi.org/10.1115/1.3260723.

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In this paper a methodology for formulating kinematic constraint equations and equations of motion for constrained mechanical systems is presented. Constraint equations and transformation matrices are expressed in terms of Euler parameters. The kinematic velocity and acceleration equations, and the equations of motion are expressed in terms of physical angular velocity of the bodies. An algorithm for solving the constrained equations of motion using a constraint stabilization technique is reviewed. Significant reduction in computation time can be achieved with this formulation and the accompan

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11

Lidström, P. "Kinematics for unilateral constraints in multibody dynamics." Mathematics and Mechanics of Solids 22, no. 8 (2016): 1654–87. http://dx.doi.org/10.1177/1081286516642270.

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This paper is concerned with the kinematics of unilateral constraints in multibody dynamics. These constraints are related to the contact between parts and the principle of impenetrability of matter and have the property that they may be active, in which case they give rise to constraint forces, or passive, in which case they do not give rise to constraint forces. In order to check whether the constraint is active or passive a distance function between parts of the multibody is required. The paper gives a rigorous definition of the distance function and derives certain of its properties. The u

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12

Dyadichev, Valery, Andrey Kolesnikov, Aleksandr Dyadichev, Ekaterina Dyadicheva, Sergey Menyuk, and Svitlana Chornobay. "Mathematical Model of Coextrusion Molding of Polymer-concrete Building Structures." E3S Web of Conferences 97 (2019): 02014. http://dx.doi.org/10.1051/e3sconf/20199702014.

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The research identifies the optimality criterion of the technological process of the coextrusion molding of polymer-concrete building structures in the form of volumetric capacity as the correlation between forms quantity and technological cycle time. The set of parameters value constraints is made. The set consists of kinematic constraints, extruder’s maximum power constrain, maximum motor torque constraint for the extruder trouble-free operation, constraint on the stress rate of the shift between layers, constraint on product cooling time, and minimum melt viscosity constraint. As a result,

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13

Samanta, B. "Dynamics of Flexible Multibody Systems Using Bond Graphs and Lagrange Multipliers." Journal of Mechanical Design 112, no. 1 (1990): 30–35. http://dx.doi.org/10.1115/1.2912575.

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A procedure is presented to study the dynamics of interconnected flexible systems using bond graphs. The concept of Lagrange multipliers, which are commonly used in analysis of constrained systems, is introduced in the procedure. The overall motions of each of the component bodies are described in terms of large rigid body motions and small elastic vibrations. Bond graphs are used to represent both rigid body and flexible dynamics of each body in a unified manner. Bond graphs of such sub-systems are coupled to one another satisfying the kinematic constraints at the interfaces to get the overal

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14

Seifried, R., and W. Blajer. "Analysis of servo-constraint problems for underactuated multibody systems." Mechanical Sciences 4, no. 1 (2013): 113–29. http://dx.doi.org/10.5194/ms-4-113-2013.

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Abstract. Underactuated multibody systems have fewer control inputs than degrees of freedom. In trajectory tracking control of such systems an accurate and efficient feedforward control is often necessary. For multibody systems feedforward control by model inversion can be designed using servo-constraints. So far servo-constraints have been mostly applied to differentially flat underactuated mechanical systems. Differentially flat systems can be inverted purely by algebraic manipulations and using a finite number of differentiations of the desired output trajectory. However, such algebraic sol

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15

Ider, S. K., and F. M. L. Amirouche. "Coordinate Reduction in the Dynamics of Constrained Multibody Systems—A New Approach." Journal of Applied Mechanics 55, no. 4 (1988): 899–904. http://dx.doi.org/10.1115/1.3173739.

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In this paper a new theorem for the generation of a basis for the null space of a rectangular matrix, with m linearly independent rows and n (n > m) columns is presented. The method is based on Gaussian row operations to transform the constraint Jacobian matrix to an uptriangular matrix. The Gram-Schmidt process is then utilized to identify basis vectors orthogonal to the uptriangular matrix. A complement orthogonal array which forms the basis for the null space for which the algebraic constraint equations are satisfied is then formulated. An illustration of the theorem application to const

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16

Costalunga, Alessandro, and Luca Consolini. "Synthesis of virtual holonomic constraints for obtaining stable constraint dynamics." Automatica 93 (July 2018): 262–73. http://dx.doi.org/10.1016/j.automatica.2018.03.030.

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17

Miller, Kenneth D., and David J. C. MacKay. "The Role of Constraints in Hebbian Learning." Neural Computation 6, no. 1 (1994): 100–126. http://dx.doi.org/10.1162/neco.1994.6.1.100.

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Models of unsupervised, correlation-based (Hebbian) synaptic plasticity are typically unstable: either all synapses grow until each reaches the maximum allowed strength, or all synapses decay to zero strength. A common method of avoiding these outcomes is to use a constraint that conserves or limits the total synaptic strength over a cell. We study the dynamic effects of such constraints. Two methods of enforcing a constraint are distinguished, multiplicative and subtractive. For otherwise linear learning rules, multiplicative enforcement of a constraint results in dynamics that converge to th

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18

Hemami, Hooshang, and Bostwick F. Wyman. "Rigid Body Dynamics, Constraints, and Inverses." Journal of Applied Mechanics 74, no. 1 (2005): 47–56. http://dx.doi.org/10.1115/1.2178359.

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Rigid body dynamics are traditionally formulated by Lagrangian or Newton-Euler methods. A particular state space form using Euler angles and angular velocities expressed in the body coordinate system is employed here to address constrained rigid body dynamics. We study gliding and rolling, and we develop inverse systems for estimation of internal and contact forces of constraint. A primitive approximation of biped locomotion serves as a motivation for this work. A class of constraints is formulated in this state space. Rolling and gliding are common in contact sports, in interaction of humans

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19

BERTHELIN, FLORENT, PIERRE DEGOND, VALERIE LE BLANC, SALISSOU MOUTARI, MICHEL RASCLE, and JULIEN ROYER. "A TRAFFIC-FLOW MODEL WITH CONSTRAINTS FOR THE MODELING OF TRAFFIC JAMS." Mathematical Models and Methods in Applied Sciences 18, supp01 (2008): 1269–98. http://dx.doi.org/10.1142/s0218202508003030.

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Recently, Berthelin et al.,4 introduced a traffic-flow model describing the formation and the dynamics of traffic jams. This model which consists of a Constrained Pressureless Gas Dynamics system assumes that the maximal density constraint is independent of the velocity. However, in practice, the distribution of vehicles on a highway depends on their velocity. In this paper, a more realistic model namely the Second Order Model with Constraints (in short SOMC) is proposed, derived from the Aw and Rascle model,1 which takes into account this feature. Moreover, when the maximal density constraint

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20

Roland, C. M., and K. L. Ngai. "Constraint dynamics and chemical structure." Journal of Non-Crystalline Solids 172-174 (September 1994): 868–75. http://dx.doi.org/10.1016/0022-3093(94)90591-6.

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21

Arimoto, Suguru, Morio Yoshida, Masahiro Sekimoto, and Kenji Tahara. "A Riemannian-Geometry Approach for Modeling and Control of Dynamics of Object Manipulation under Constraints." Journal of Robotics 2009 (2009): 1–16. http://dx.doi.org/10.1155/2009/892801.

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A Riemannian-geometry approach for modeling and control of dynamics of object manipulation under holonomic or non-holonomic constraints is presented. First, position/force hybrid control of an endeffector of a multijoint redundant (or nonredundant) robot under a holonomic constraint is reinterpreted in terms of “submersion” in Riemannian geometry. A force control signal constructed in the image space of the constraint gradient is regarded as a lifting (or pressing) in the direction orthogonal to the kernel space. By means of the Riemannian distance on the constraint submanifold, stability of p

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22

Chou, Glen, Dmitry Berenson, and Necmiye Ozay. "Learning constraints from demonstrations with grid and parametric representations." International Journal of Robotics Research 40, no. 10-11 (2021): 1255–83. http://dx.doi.org/10.1177/02783649211035177.

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We extend the learning from demonstration paradigm by providing a method for learning unknown constraints shared across tasks, using demonstrations of the tasks, their cost functions, and knowledge of the system dynamics and control constraints. Given safe demonstrations, our method uses hit-and-run sampling to obtain lower cost, and thus unsafe, trajectories. Both safe and unsafe trajectories are used to obtain a consistent representation of the unsafe set via solving an integer program. Our method generalizes across system dynamics and learns a guaranteed subset of the constraint. In additio

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23

Lee, K. "Analysis of the dynamic contact between rotating spur gears by finite element and multi-body dynamics techniques." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 215, no. 4 (2001): 423–35. http://dx.doi.org/10.1243/0954406011520850.

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A numerical method is presented for the dynamic contact analysis of spur gears rotating with very high angular speeds. For each gear an elastic tooth of distributed mass is connected to a rigid disc with kinematic constraints, and finite element formulations are used for the equations of motion of the teeth. The velocity and acceleration as well as the position of the contact point sliding on the mating gear teeth are precisely computed by simultaneously using the motions of a pair of rotating tooth surfaces. The equations of motion subjected to the kinematic constraint and contact condition a

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24

Yoon, Sugjoon, Robert M. Howe, and Donald T. Greenwood. "Constraint violation stabilization using gradient feedback in constrained dynamics simulation." Journal of Guidance, Control, and Dynamics 15, no. 6 (1992): 1467–74. http://dx.doi.org/10.2514/3.11410.

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25

Wösle, M., and F. Pfeiffer. "Dynamics of Multibody Systems Containing Dependent Unilateral Constraints with Friction." Journal of Vibration and Control 2, no. 2 (1996): 161–92. http://dx.doi.org/10.1177/107754639600200203.

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In couplings of machines and mechanisms, backlash and friction phenomena are always occurring. Whether stick-slip phenomena take place depends on the structure of such couplings. These processes can be modeled as multibody systems with a time-varying topology. Making use of Lagrange multiplier methods with a mathematical formulation of the contact problem is very efficient for large systems with many constraints. The differential-algebraic equations of a system are transformed into a resolvable mathematical form by means of contact laws. In the following, rigid multibody systems with dependent

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26

Askar, S. S., A. Ibrahim, and A. A. Elsadany. "Dynamics of a Heterogeneous Constraint Profit Maximization Duopoly Model Based on an Isoelastic Demand." Complexity 2021 (March 27, 2021): 1–14. http://dx.doi.org/10.1155/2021/6687544.

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A Cournot duopoly game is a two-firm market where the aim is to maximize profits. It is rational for every company to maximize its profits with minimal sales constraints. As a consequence, a model of constrained profit maximization (CPM) occurs when a business needs to be increased with profit minimal sales constraints. The CPM model, in which companies maximize profits under the minimum sales constraints, is an alternative to the profit maximization model. The current study constructs a duopoly game based on an isoelastic demand and homogeneous goods with heterogeneous strategies. In the even

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Udwadia, Firdaus E., and Phailaung Phohomsiri. "Explicit Poincaré equations of motion for general constrained systems. Part I. Analytical results." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 463, no. 2082 (2007): 1421–34. http://dx.doi.org/10.1098/rspa.2007.1825.

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This paper gives the general constrained Poincaré equations of motion for mechanical systems subjected to holonomic and/or nonholonomic constraints that may or may not satisfy d'Alembert's principle at each instant of time. It also extends Gauss's principle of least constraint to include quasi-accelerations when the constraints are ideal, thereby expanding the compass of this principle considerably. The new equations provide deeper insights into the dynamics of multi-body systems and point to new ways for controlling them.

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Kim, J. K., I. S. Chung, and B. H. Lee. "Determination of the Feedback Coefficients for the Constraint Violation Stabilization Method." Proceedings of the Institution of Mechanical Engineers, Part C: Mechanical Engineering Science 204, no. 4 (1990): 233–42. http://dx.doi.org/10.1243/pime_proc_1990_204_101_02.

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A constraint violation stabilization method has been used to solve a mixed set of algebraic and differential equations formulated for the dynamic analysis of a constrained mechanical system. However, the absence of a clear-cut method for determining the feedback coefficients associated with this method makes it unattractive and unreliable for its user. This paper presents a method for determining the optimal feedback coefficients which minimize the propagation of constraint violation. This method is based on the stability analysis for the error propagation dynamics of the modified constrained

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29

Ngai, K. L., C. M. Roland, and A. F. Yee. "A Constraint Dynamics Approach to Rubber Elasticity." Rubber Chemistry and Technology 66, no. 5 (1993): 817–26. http://dx.doi.org/10.5254/1.3538346.

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Abstract The coupling model of relaxation is applied to crosslinked rubber, with a connection drawn between the dynamics of network junctions and statistical mechanics derived rubber elasticity theory. The suggestion that unifying concepts must underlie dynamical models and thermodynamic theories is shown to be supported by analyses of recent 31P NMR spectroscopy measurements by Shi, Dickinson, MacKnight and Chien on polytetrahydrofuran networks and of our mechanical relaxation data on stretched and unstretched polycarbonate.

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Gottwald, G. A. "Controlling balance in an ensemble Kalman filter." Nonlinear Processes in Geophysics 21, no. 2 (2014): 417–26. http://dx.doi.org/10.5194/npg-21-417-2014.

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Abstract. We present a method to control unbalanced fast dynamics in an ensemble Kalman filter by introducing a weak constraint on the imbalance in a spatially sparse observational network. We show that the balance constraint produces significantly more balanced analyses than ensemble Kalman filters without balance constraints and than filters implementing incremental analysis updates (IAU). Furthermore, our filter with the weak constraint on imbalance produces good rms error statistics which outperform those of ensemble Kalman filters without balance constraints for the fast fields.

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Chang, Bo Yan, Guo Guang Jin, Jian Sheng Dai, and Jin Tian Yun. "The Dynamics Analysis of Metamorphic Mechanisms Based on Fully Cartesian Coordinates Method." Advanced Materials Research 139-141 (October 2010): 2391–96. http://dx.doi.org/10.4028/www.scientific.net/amr.139-141.2391.

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Because of special structure and dynamic behavior, the dynamic equations of metamorphic mechanism are variable during the process of configuration change. In order to combine dynamics analysis and structure design of metamorphic mechanisms intimately, a new method of forming dynamic model of metamorphic mechanisms is proposed based on fully Cartesian coordinate’s method and the relation between origin mechanism and sub-configuration. A new concept named origin constraint equation is introduced which can be converted into constraint equations of each sub-configuration easily by adding correspon

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Jain, Abhinandan, Calvin Kuo, Paramsothy Jayakumar, and Jonathan Cameron. "Constraint Embedding for Vehicle Suspension Dynamics." Archive of Mechanical Engineering 63, no. 2 (2016): 193–213. http://dx.doi.org/10.1515/meceng-2016-0011.

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Abstract The goal of this research is to achieve close to real-time dynamics performance for allowing auto-pilot in-the-loop testing of unmanned ground vehicles (UGV) for urban as well as off-road scenarios. The overall vehicle dynamics performance is governed by the multibody dynamics model for the vehicle, the wheel/terrain interaction dynamics and the onboard control system. The topic of this paper is the development of computationally efficient and accurate dynamics model for ground vehicles with complex suspension dynamics. A challenge is that typical vehicle suspensions involve closed-ch

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Dean, Thomas J., G. Dale Meyer, and Julio DeCastro. "Determinants of New-Firm Formations in Manufacturing Industries: Industry Dynamics, Entry Barriers, and Organizational Inertia." Entrepreneurship Theory and Practice 17, no. 2 (1993): 49–60. http://dx.doi.org/10.1177/104225879301700205.

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This article utilizes the Ideas of Austrian economists, Industrial organization economists, and organization theorists to build a model of new-firm creation In manufacturing industries. Market dynamics create disequilibrium and profit opportunities for entrepreneurs. Whether available opportunities are exploited by existing firms, or through the founding of new firms Is dependent on the constraints on each of these types of entrepreneurs. Entry barriers tend to constrain new firms and therefore decrease the relative occurrence of new business formations. Organizational Inertia acts as a constr

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GEURTS, BERNARD J., and FREDERIK W. WIEGEL. "SIMULATION OF THE DYNAMICS OF A MACROMOLECULE IN A RANDOM CONSTRAINT CAGE." Modern Physics Letters B 01, no. 01n02 (1987): 57–60. http://dx.doi.org/10.1142/s0217984987000089.

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We determine the centre of mass diffusion coefficient D and the chain relaxation time T of a macromolecule diffusing through a random constraint cage. This cage models the average topological constraints on the motion of a particular polymer, imposed by the other polymers in the system. The constraint cage consists of regularly spaced constraint lines on a cubic lattice which are “active” with a probability p and absent with a probability 1−p. To a good approximation D≈A(p)N−α(p) and T≈B(p)Nβ(p) if N≫1. The exponents α and β show two regions of very rapid change at pc,1≈0.30 and at pc,2≈0.98.

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Wu, S. C., and E. J. Haug. "A Substructure Technique for Dynamics of Flexible Mechanical Systems With Contact-Impact." Journal of Mechanical Design 112, no. 3 (1990): 390–98. http://dx.doi.org/10.1115/1.2912620.

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A substructure synthesis method is proposed to account for contact-impact effects in flexible components of mechanical systems. Components that may come into contact are divided into substructures, on each of which local deformation modes are defined to describe deformation fields of components. Constraint modes and fixed interface normal modes are used to account for elastic deformation within each substructure. A constraint addition-deletion technqiue is used to determine when contact occurs, account for the effect of contact constraints during the period of contact, and delete constraints a

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English, A. D., Paul T. Inglefield, Alan A. Jones, and Yong Zhu. "Polymer segmental dynamics and entanglement constraint." Polymer 39, no. 2 (1998): 309–13. http://dx.doi.org/10.1016/s0032-3861(97)00286-3.

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37

Phillips, J. C. "Constraint theory and hierarchical protein dynamics." Journal of Physics: Condensed Matter 16, no. 44 (2004): S5065—S5072. http://dx.doi.org/10.1088/0953-8984/16/44/004.

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Bailey, A. G., C. P. Lowe, and A. P. Sutton. "Efficient constraint dynamics using MILC SHAKE." Journal of Computational Physics 227, no. 20 (2008): 8949–59. http://dx.doi.org/10.1016/j.jcp.2008.07.002.

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Jarzębowska, Elżbieta, Andrzej Urbaś, and Krzysztof Augustynek. "Analysis of Influence of a Crane Flexible Supports, Link Flexibility, and Joint Friction on Vibration Associated with Programmed Motion Execution." Journal of Vibration Engineering & Technologies 8, no. 2 (2019): 337–50. http://dx.doi.org/10.1007/s42417-019-00186-1.

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Abstract Background The paper presents vibration analysis of dynamic models of systems with flexible mechanical components, friction modeled and subjected to position and kinematic programmed constraints, which can be imposed as control goals, work or service task demands. Methods The constrained dynamics is derived using an automated computational procedure dedicated to constrained systems. The procedure was successfully implemented to rigid system models. A class of systems composed of flexible parts and subjected to programmed motions is considered in the paper. Their motion analysis has to

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Li, Chenming, Han Zhao, Shengchao Zhen, et al. "Trajectory Tracking Control of Parallel Manipulator Based on Udwadia-Kalaba Approach." Mathematical Problems in Engineering 2017 (December 14, 2017): 1–12. http://dx.doi.org/10.1155/2017/8975743.

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There have been many approaches for achieving the trajectory tracking control of parallel manipulator. However, these approaches are complex for calculating Lagrangian multipliers. In this paper, unlike the former approaches, a new approach of trajectory tracking control which is based on Udwadia-Kalaba approach is presented. Using this methodology, we can obtain a concise and explicit equation of motion and consider holonomic and nonholonomic constraint whether it is ideal or nonideal simultaneously. The most important difference is that we divide constraints into structural constraints and p

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Enferadi, Javad, and Mohammad Tavakolian. "Lagrangian Dynamics Analysis of a XY-Theta Parallel Robotic Machine Tool." Periodica Polytechnica Mechanical Engineering 61, no. 2 (2017): 107. http://dx.doi.org/10.3311/ppme.9368.

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Dynamics of a highly stiff parallel machine tool is the subject of this paper. High stiffness, good accuracy, relatively large workspace and free of singularities on the whole workspace makes the manipulator suitable for machining applications as an XY-Theta precision table. First, obtaining kinematics constraints, inverse kinematics analysis and velocity analysis are performed. Next, using six redundant generalized coordinates, we obtain Lagrangian of the manipulator. Also, a Lagrangian approach is proposed to obtain dynamics equations of the machine tool using three Lagrangian multipliers. T

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Tahouni, Amin, Mehdi Mirzaei, and Behrouz Najjari. "Applied nonlinear control of vehicle stability with control and state constraints." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 234, no. 1 (2019): 191–211. http://dx.doi.org/10.1177/0954407019848858.

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For the vehicle dynamic control system, to guarantee directional stability in risky maneuvers, the side-slip angle should be restricted to the admissible range when the yaw rate tracks the proposed desired response for enhanced steerability. Meanwhile, the control input of the external yaw moment produced by asymmetric braking forces should be calculated in the practical range according to the capacity of tire forces. In the present study, a novel constrained controller with input and state constraints is developed. To this aim, a cost function consisting of predicted continuous response of ya

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Liu, Fei, Jingrui Zhang, and Quan Hu. "A modified constraint force algorithm for flexible multibody dynamics with loop constraints." Nonlinear Dynamics 90, no. 3 (2017): 1885–906. http://dx.doi.org/10.1007/s11071-017-3770-0.

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Maolin, Liao, Yan Yao, and Liu Yang. "Optimization of the Vibro-Impact Capsule System for Promoting Progression Speed." MATEC Web of Conferences 148 (2018): 10002. http://dx.doi.org/10.1051/matecconf/201814810002.

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This paper studies the dynamics of vibro-impact capsule systems with one-sided and double-sided constraints under variations of control parameters, including frequency of excitation, mass ratio, and stiffness ratio. The aim of this study is to optimize the progression speed of the capsule system. Extensive comparisons reveal that the capsule system with one-sided constraint is better than the one with double-sided constraints in terms of progression speed. Moreover, the system’s period-one one-right-impact motion is proved as the ideal vibration condition due to its lowest energy consumption f

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Chen, D. C., A. A. Shabana, and J. Rismantab-Sany. "Generalized Constraint and Joint Reaction Forces in the Inverse Dynamics of Spatial Flexible Mechanical Systems." Journal of Mechanical Design 116, no. 3 (1994): 777–84. http://dx.doi.org/10.1115/1.2919450.

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In both the augmented and recursive formulations of the dynamic equations of flexible mechanical systems, the inerita, constraints, and applied forces must be properly defined. The inverse dynamics is a commonly used approach for the force analysis of mechanical systems. In this approach, the system is kinematically driven using specified motion trajectories, and the objective is to determine the driving forces and torques. In flexible body dynamics, however, a force that acts at a point on the deformable body is equipollent to a system, defined at another point, that consists of the same forc

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Soma, Mifiamba, and Somdouda Sawadogo. "Boundary Sentinel with Given Sensitivity in Population Dynamics Problem and Parameters Identification." European Journal of Pure and Applied Mathematics 12, no. 3 (2019): 1277–96. http://dx.doi.org/10.29020/nybg.ejpam.v12i3.3479.

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The notion of sentinels with given sensitivity was introduced by J.L.Lions [11] in order to identify parameters in the problem of pollution ruled by a parabolic equation. He proves that the existence of such sentinels is reduced to the solution of exact controllability problem with constraints on the state. In population dynamics model, we reconsider this notion of sentinels in a more general framework. We prove the existence of the boundary sentinels by solving a boundarynull-controllability problem with constraint on the control. Our results use Carleman inequality which is adapted to the co

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CRASMAREANU, MIRCEA, and IULIAN STOLERIU. "NONHOLONOMIC DYNAMICS OF SECOND ORDER AND THE HEISENBERG SPINNING PARTICLE." International Journal of Geometric Methods in Modern Physics 09, no. 07 (2012): 1220010. http://dx.doi.org/10.1142/s0219887812200101.

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The equations of motion for the associated constrained Lagrangian to a nonholonomic Lagrangian of second order are computed. The spinning particle subject to the Heisenberg constraint is treated as example and its dynamics is completely described.

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Shao, Xing-Guo, Zhen-Cai Zhu, Qing-Guo Wang, Peter CY Chen, Bin Zi, and Guo-Hua Cao. "Non-smooth dynamical analysis and experimental validation of the cable-suspended parallel manipulator." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 226, no. 10 (2012): 2456–66. http://dx.doi.org/10.1177/0954406211435585.

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The cable-suspended parallel manipulator replaces the rigid links of traditional parallel robot. The unilateral property of the cable complicates the dynamic analysis of such manipulator and further induces difficulty in control problem. The set-valued tension law is proposed to model the unilateral constraint of the cable, and the dynamics of cable-suspended parallel manipulator is analyzed in the framework of non-smooth dynamics. The resulting non-smooth dynamics model consists of a set of differential–algebraic equations with inequality constraints. Its solution is found by the Moreau midpo

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Brown, David. "The Force of Constraint in Predictor-Corrector Algorithms for Shake Constraint Dynamics." Molecular Simulation 18, no. 6 (1997): 339–48. http://dx.doi.org/10.1080/08927029708024129.

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Rawlings, Craig M. "Cognitive Authority and the Constraint of Attitude Change in Groups." American Sociological Review 85, no. 6 (2020): 992–1021. http://dx.doi.org/10.1177/0003122420967305.

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Are individuals’ attitudes constrained such that it is difficult to change one attitude without also changing other attitudes? Given a lack of longitudinal studies in real-world settings, it remains unclear if individuals have coherent attitude systems at all—and, if they do, what produces attitude constraint. I argue and show that groups can endogenously produce attitude constraint via cognitive authorities. Within groups, cognitive authorities explicitly link attitudes and generate feelings of connectedness among members, thereby facilitating the interpersonal processing of attitudes. Using

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