Relative Degrees Of Freedom Research Articles

Design and control of a three‐degrees‐of‐freedom, in‐parallel, actuated manipulator

AbstractThe mechanics, design, and control of a 3–degrees‐of‐freedom, in‐parallel, pneumatically actuated manipulator are presented. The manipulator consists of two platforms connected by three serial chains. The kinematic design is such that the three relative degrees of freedom between the two plates allow the manipulator to accomodate uncertainties and sustain impacts while contacting and interacting with unknown environments. In particular, the manipulator is naturally compliant in translation along the approach direction as well as in rotations about axes perpendicular to the approach direction, while it is stiff in other directions. In this article, an overview of the manipulator kinematics, a description of the manipulator system and the associated hardware, and experimental results on the dynamic behavior of a prototype are presented. © 1994 John Wiley & Sons, Inc.

Influence of the counterpoise correction on the optimized relative degrees of freedom in the H-bonded complex water-formamide

The correction of the basis set superposition error by the counterpoise method has been investigated at the SCF level for the weak H-bonded water-formamide complex and the results have been compared with the uncorrected results at the SCF, post SCF and semi-empirical AM1 and MNDO levels. Our particular concern has been the determination of the three optimized relative degrees of freedom and the relative stability of threeCs geometrical conformations. The conclusions are that the counterpoise correction weakly conditions the variation in the degrees of freedom and the relative stabilities of the three conformers. The correction is obviously inadequate to describe intramolecular deformation.

Feedback loop between kinship and dominance: the macaque model

There is growing evidence that macaque social systems represent sets of coadapted traits in which strength of hierarchies and degree of nepotism covary. A framework is developed to explain the link between dominance and kinship phenomena, assuming that power brought by alliances among non-kin is allometrically related to those involving relatives. This can account for the type of social relationships observed in "despotic" systems vs. "egalitarian" ones. When social bonds are mostly founded on kinship, lineages are closed and social power generated by coalitions among relatives may reach high levels; social power frequently outweighs the fighting abilities of single individuals, and asymmetry of dominance between group members may be marked. When lineages are more open, social bonds and alliances are less kin-biased, social relationships are more equal, and as the influence of coalitions is less important, the individual retains a certain degree of freedom in relation to the power of kin-networks. Acknowledging that the balance between individual and social power is not set at the same level across different species can explain a number of variations in rules of rank inheritance and relative dominance of males and females among macaques. The framework illustrates how epigenetic processes may shape complex features of primate social systems, and offers opportunities for testing.

Mechanical Couplings—A General Geometrical Theory, Part 1: Theorems on Algebraic Loci and Couplings

In the broad category of couplings considered the two coupled bodies have either one or two relative degrees of freedom. Points, planes, and lines guided by such couplings trace a variety of spatial loci restricted by the requirement that they must all be algebraic. The order, class, or degree of such loci is related to the tracing element, and is proved to be always exactly identifiable with an invariant property of a particular coupling, here called the “feather” of the coupling. This property is central to two new theorems which unify many hitherto distinct facets of linkages. Some shortcuts are revealed to assist in more detailed study of mechanical movements.

Path integrals and optical potentials for elastic and inelastic scattering

When relative degrees of freedom are taken to traverse a fixed trajectory R(τ), the properties of Feynman path integrals are used to derive a series expansion of the logarithm of the internal state elastic scattering amplitude in terms of the internal relative coupling potential. Likewise transition amplitudes for inelastic scattering are expressed in terms of an exponential of an infinite series of 2 x 2 matrices. These results represent a reordering of the usual perturbation series of time dependent quantum mechanics to obtain a series expansion in the exponential as well as truncation from the space of all channels to that of only one or two (or more, if necessary). When the relative degrees of freedom are to be treated quantum mechanically, R(τ) is now the integration variable in a Feynman path integral. The above noted exponentiated series then correspond to the exact optical potentials for elastic and inelastic scattering within the Feynman path integral formulation of quantum mechanics.

Problems of sexuality as encountered in a general family practice.

In this brief presentation we shall attempt to identify a philosophical attitude in the development of a meaningful approach to the problems of sexuality as encountered in a general family practice. Our patient population is fairly homogeneous, mostly middle class, and semi-rural. Weare committed to the delivery of a comprehensive health care to individual and family, within the framework of a psychiatric orientation. Sexuality must be conceptualized as far more than a physical phenomenon. It is a major aspect of the total personality, related to one's emotional and social adjustment as well as to physical development. The significance of human sexuality can be fully understood only by relating it to the total adjustment pattern of the individual, within the context of family and society. An individual's sense of identity, his thinking and behavior, social and occupational activities, and many other facets of his existence are related to his total sexuality. Today, for the first time in our short history as a nation, the individual is confronted with an incredible array of competing sexual value systems. For the first time, also, he is granted a relative degree of freedom to make personal choices on a much broader spectrum than was formerly possible. Socially acceptable patterns of behavior today have a multi-variable range of normality. Since sexual behavior is a function of the total personality, sex education must concern itself with the biological, psychological, and social aspects which effect formation of person-

Nonreactive Molecular Encounters

Low-energy molecular collisions are discussed from a point of view that emphasizes the role of the internal degrees of freedom of the colliding molecules. The theory centers attention on the mechanism of energy transfer from kinetic energy of relative motion into internal energy and vice versa. It is shown that irrespective of the over-all energy transfer (which may be zero), the collision event proceeds via steps of energy migration between internal and relative degrees of freedom. This feature is absent in the available first-order theories. An approximation scheme which includes this feature even in first order is suggested, and a self-consistent-field scheme where each collision partner moves in the average field of the other partner is discussed. The migration of kinetic energy into internal degrees of freedom results in the temporary formation of bound states. Such intermediates are of importance in the study of intermolecular forces, vibrational excitations, contact charge-transfer complexes, and three-body recombinations. The collision of two hydrogen atoms is discussed in the adiabatic approximation, where the temporary bound state is due to charge redistribution. The mechanism of three-body recombination is discussed and a recombination rate constant is calculated.