Degree of Freedom

KHR-I has been developed on the purpose of research about biped walking. It has 21 DOF without hands and head, which has 12 DOF in legs, 1 DOF in torso, and 8 DOF in arms. The objective of KHR-2 (41 DOF) was to develop the humanoid which can walk on the living-floor with human-like appearance and movement. KHR-3 has the purpose that it has more human-like features, movements and human-friendly character. Mechanical design of KHR-3 is presented on this paper. The design concept, lower body design, upper body design and actuator selection of joints are included in this paper. We have developed and published KHR-I and 2 in last three years. KHR3 platform is based on KHR-2. It has 41 degree of freedom (DOF), 125 cm height, and 55 kg weight. The differences from KHR-2 are mechanical stiffness and detailed design of the frame in the mechanical point of view. Stiffness of the frame is increased and detailed design about joints and link frame has been modified or redesigned. We introduced exterior art design concept on KHR-2 in beginning, and the concept has been implemented on KHR-3 in mechanical design stage

We present a new approach to path planning, called the "Ariadne's clew algorithm". It is designed to find paths in high-dimensional continuous spaces and applies to robots with many degrees of freedom in static, as well as dynamic environments - ones where obstacles may move. The Ariadne's clew algorithm comprises two sub-algorithms, called SEARCH and EXPLORE, applied in an interleaved

We calculate the incoherent resonant and non-resonant scattering production of sterile neutrinos in the early universe. We find ranges of sterile neutrino masses, vacuum mixing angles, and initial lepton numbers which allow these species to constitute viable hot, warm, and cold dark matter (HDM, WDM, CDM) candidates which meet observational constraints. The constraints considered here include energy loss in core collapse supernovae, energy density limits at big bang nucleosynthesis, and those stemming from sterile neutrino decay: limits from observed cosmic microwave background anisotropies, diffuse extragalactic background radiation, and Li-6/D overproduction. Our calculations explicitly include matter effects, both effective mixing angle suppression and enhancement (MSW resonance), as well as quantum damping. We for the first time properly include all finite temperature effects, dilution resulting from the annihilation or disappearance of relativistic degrees of freedom, and the scattering-rate-enhancing effects of particle-antiparticle pairs (muons, tauons, quarks) at high temperature in the early universe.

We use gas-dynamical simulations of galaxy clusters to compare their X-ray and strong lensing properties. Special emphasis is laid on mass estimates. The cluster masses range between 6x10^14 and 4x10^15 M_solar, and they are examined at redshifts between 1 and 0. We compute the X-ray emission of the intracluster gas by thermal bremsstrahlung, add background contamination, and mimic imaging and spectral observations with current X-ray telescopes. Although the beta model routinely provides excellent fits to the X-ray emission profiles, the derived masses are typically biased low because of the restricted range of radii within which the fit can be done. For beta values of ~2/3, which is the average in our numerically simulated sample, the mass is typically underestimated by ~40 per cent. The masses of clusters that exhibit pronounced substructure are often substantially underestimated. We suggest that the ratio between peak temperature and emission-weighted average cluster temperature may provide a good indicator for ongoing merging and, therefore, for unreliable mass estimates. X-ray mass estimates are substantially improved if we fit a King density profile rather than the beta model to the X-ray emission, thereby dropping the degree of freedom associated with beta. Clusters selected for their strong lensing properties are typically dynamically more active than typical clusters. Bulk flows in the intracluster gas contain a larger than average fraction of the internal energy of the gas in such objects, hence the measured gas temperatures are biased low. The bulk of the optical depth for arc formation is contributed by clusters with intermediate rather than high X-ray luminosity. Arcs occur predominantly in clusters that exhibit substructure and are not in an equilibrium state. Finally, we explain why the X-ray emission of some observed arc clusters is cooler than predicted from the arc geometry. All clusters for which this happens in our simulations show structure in velocity space, indicating ongoing merging along the line of sight. The temperature discrepancy is probably a projection effect.

Structural analysis plays a crucial role during the designing of mechanism. Structural analysis of kinematic chain deals with connection among the members of kinematic chain and its mobility. In the present work efforts has been made to provide adequate solution of structural analysis of kinematic chain by considering the example of twelve link mechanism. With the help of graph theory the structure of the kinematic chain is shown by its kinematic graph in which the links shows the vertices and the joints shows the edges. The kinematic graph is then represented by incidence matrix or adjacency matrix. This matrix shows the connection between the links. Then a simple method is applied on the matrix to determine the coefficient of characteristic polynomial equation. Finally for mobility analytic test is performed to find whether kinematic chain possess total, fractioned, or partial degree of freedom.

All over the world it can be noticed that product miniaturisation is a central theme in product development for different application areas. In robotics scientific research, one of the most important approaches is concerning the increase of the positioning accuracy by the use of parallel structures [3], [4], [5]. In this paper some variants of parallel robots and micro-robots with three, four and five degrees of freedom are presented, which are used for manipulation within high precision assembling processes. The corresponding kinematic models have been developed. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The authors discuss the overall structural design of a self-contained hydraulic six-legged machine, called MECANT I, which has been constructed for studying possible applications of legged vehicles in natural environments, like forests. First, the main mechanical solutions and control hardware of the machine are presented. The systematic approach to the motion planning of a legged vehicle and some algorithmical features are discussed. The special features of the leg control are presented. The use of a simulator in the design work is discussed, and the main principles of the control software structure, which supports fast software design and testing, are presented. Some continuing research topics and the present situation are discussed

An interpretation of the cold fission events in thermal-neutron-induced fission of heavy nuclei is given. The descent from the saddle point is considered as a dynamical process with reversible coupling between collective and intrinsic degrees of freedom. The distribution function for the collective variables is expressed as a product of two terms: the adiabatical and the dynamical factors. A simple model for symmetric fission to study the mass distribution is presented. As example, the calculations are performed for the nucleus 264Fm. Gross features of the cold fission are discussed as well as the dependence of the theoretical mass distribution on the parameters of the model.

We present a general approach to incorporate hadronic as well as quark degrees of freedom in a unified approach. This approach implements the correct degrees of freedom at high as well as low temperatures and densities. An effective Polyakov loop field serves as the order parameter for deconfinement. We employ a well-tested hadronic flavor-SU(3) model based on a chirally symmetric formulation that reproduces properties of ground state nuclear matter and yields good descriptions of nuclei and hypernuclei. Excluded volume effects simulating the finite size of the hadrons drive the transition to quarks at high temperatures and densities. We study the phase structure of the model and the transition to the quark gluon plasma and compare results to lattice gauge calculations.

We consider planning and control problems for underactuated manipulators, a special instance of mechanical systems having fewer input commands than degrees of freedom. This class includes robots with passive joints, elastic joints, or flexible links. Structural control properties are investigated, showing that manipulators with passive joints in the absence of gravity are the most difficult to control. With reference to