Analysis of balance control methods based on inverted pendulum for legged robots

Methods of balance control for a legged robot, the model of which is presented as a two-section inverted pendulum, are considered. The following balance methods for humanoid robots are analysed: the parallel algorithm of the network operator method; the method of natural synergies; the method of fuzzy control, the spherical inverted pendulum mode, a dual length linear inverted pendulum method. The best of these methods will be used in the development of the Russian anthropomorphic robot Antares

ISSUES CONCERNING PROTECTION OF THE VINE FAMILY (FAMILY <i> VITACEAE </i> JUSS.) IN THE RUSSIAN FAR EAST

Analyzing classification features of vines of the family Vitaceae Juss. in the Russian Far East (RFE) confirms the need for their protection within the region. Protection should be extended to species of the rarity categories 1, 2 and 3. For the RFE (as a whole) these are the species: Ampelopsis japonica (Thunb.) Makino, Parthenocissus tricuspidata (Siebold & Zucc.) Planch. - 1; Ampelopsis heterophylla (Thunb.) Siebold & Zucc. - 2; Ampelopsis brevipedunculata (Maxim.) Trautv., Vitis coignetiae Pulliat ex Planch. - 3; and Vitis amurensis Rupr. - 4. Our field studies in the territory of the Russian Far East have allowed us to assess the condition of a number of woody vines in natural habitats, clarify the distribution and propose measures for conservation of their gene pool. It is recommended to supplement the list of nature reserves and sanctuaries with a number of areas where woody vines occur

Magnetic relaxation in finite two-dimensional nanoparticle ensembles

We study the slow phase of thermally activated magnetic relaxation in finite two-dimensional ensembles of dipolar interacting ferromagnetic nanoparticles whose easy axes of magnetization are perpendicular to the distribution plane. We develop a method to numerically simulate the magnetic relaxation for the case that the smallest heights of the potential barriers between the equilibrium directions of the nanoparticle magnetic moments are much larger than the thermal energy. Within this framework, we analyze in detail the role that the correlations of the nanoparticle magnetic moments and the finite size of the nanoparticle ensemble play in magnetic relaxation.Comment: 21 pages, 4 figure

Energy Flow Puzzle of Soliton Ratchets

We study the mechanism of directed energy transport for soliton ratchets. The energy flow appears due to the progressive motion of a soliton (kink) which is an energy carrier. However, the energy current formed by internal system deformations (the total field momentum) is zero. We solve the underlying puzzle by showing that the energy flow is realized via an {\it inhomogeneous} energy exchange between the system and the external ac driving. Internal kink modes are unambiguously shown to be crucial for that transport process to take place. We also discuss effects of spatial discretization and combination of ac and dc external drivings.Comment: 4 pages, 3 figures, submitted to PR

The arions generation by magnetodipole waves of pulsars and magnetars in a constant magnetic field

The influence of the gravitational fields of pulsars and magnetars on the arion emission during the propagation of magnetodipole waves in a constant magnetic field has been evaluated. The solution of the equation was obtained and the flux of arions emitted by magnetodipole waves during their propagation in a constant magnetic field was found. It is shown that the amplitude of the born arion wave at a distance from the source of magnetodipole radiation of a pulsar or magnetar $(r\to\infty)$ in the considered case tends to a constant value. The intensity of the arion emission in the solid angle element and the amount of arion energy $\overline{I}$, emitted in all directions per unit time grow quadratically with increasing distance, traveled by the magnetodipole radiation of a pulsar or magnetar in a constant magnetic field. Such growth of the energy of the born arion wave is due to the fact that in the considered problem constant magnetic field is defined in the whole space. In reality, the galactic and intergalactic magnetic fields can be represented in this form only in regions of space of finite dimensions, outside of which the force lines of their induction vector are curved. Therefore, it is possible to apply these results only in a region of space for which $r\leq L_{coh}<\infty$, where $L_{coh}$ is the coherence length, the distance at which the force lines of the induction vector can be considered as straight lines. An estimate for the value of the coupling constant of photons with arions is obtained