Kinematic Connection Research Articles

A kinematic study of planetary nebulae in the dwarf irregular galaxy IC10

We present positions, kinematics, and the planetary nebula luminosity function (PNLF) for 35 planetary nebulae (PNe) in the nearest starburst galaxy IC10 extending out to 3kpc from the galaxy's centre. We take advantage of the deep imaging and spectroscopic capabilities provided by the spectrograph FOCAS on the 8.2m Subaru telescope. The PN velocities were measured through the slitless-spectroscopy technique, which allows us to explore the kinematics of IC10 with high precision. Using these velocities, we conclude that there is a kinematic connection between the HI envelope located around IC10 and the galaxy's PN population. By assuming that the PNe in the central regions and in the outskirts have similar ages, our results put strong observational constraints on the past tidal interactions in the Local Group. This is so because by dating the PN central stars, we, therefore, infer the epoch of a major episode of star formation likely linked to the first encounter of the HI extended envelope with the galaxy. Our deep [OIII] images also allow us to use the PNLF to estimate a distance modulus of 24.1+/-0.25, which is in agreement with recent results in the literature based on other techniques.

Elements of Synthesis and Experiment for Parallel Robots

Parallel robots have received special interest due to their advantages over conventional serial mechanisms: high rigidity, high load capacity, high velocity and high precision. The parallel robot is a mechatronic system and requires to be designed in the spirit of the mechatronic philosophy. The use of a parallel robot in a given application requires a careful analysis of the structure and of the indispensable parameters. Structural synthesis of mechanisms for parallel robots is addressed in detail. This paper proposes a method of structural synthesis of the parallel robotic mechanism according to the concept of the mechatronic philosophy and of the kinematic connections. The authors offer a system for analyzing the robot performances based on the3D CompuGaugeequipment.

PERFECT AND IMPERFECT NONHOLONOMIC KINEMATIC CONNECTIONS OF THE ROAD WHEEL WITH SURFACE

In the work there are various types of equations describing nonholonomic kinematic connections of the road wheel with the supporting surface. The authors deal with evidence of the adequacy of the results of the pilot studies, and provide justification for the use of each equation type.

THE STRUCTURAL SYNTHESIS OF THE PARALLEL ROBOTS

Parallel robots have received special interest due to their advantages over conventional serial mechanisms: high rigidity, high load capacity, high velocity and high precision. Parallel robot is a mechatronic system and requires to be designed in the spirit of mechatronic philosophy. This paper proposes a method of structural synthesis of parallel robotic mechanism according to the concept of mechatronic philosophy and of the kinematic connections.The V design model - V design cycle - is adopted. The methodology considers an iterative process corresponding to the stages of product design development. During the design process, one cannot consider a universal parallel robot due to the reduced workload. The use of a parallel robot in a given application requires careful analysis of the structure and of the indispensable parameters. Structural synthesis of mechanisms for parallel robots is addressed in detail.The kinematic connections are defined and classified; the conceptual mode of operation and the structural analysis of the mechanisms are noted. Principles of structural synthesis using the concept of the kinematic connections are discussed; edifying examples of planar and spatial parallel robot structures for this synthesis are summarized.http://dx.doi.org/10.5755/j01.mech.17.3.505

Planetary nebulae as tracers of the kinematic structure of the starburst galaxy IC 10

AbstractThe Local Group dwarf irregular galaxy IC 10 is the nearest starburst galaxy (at 725 kpc) and presents extended and complex HI kinematics. It is believed that IC 10 is still experiencing an intense and very recent burst of star formation, likely triggered by infalling gas from an extended envelope which is counter-rotating with respect to the galaxy proper rotation. In this contribution we summarize our preliminary results (Gonçalves et al. 2011, in prep.) obtained by performing a kinematic analysis of the PN population of IC 10. Our aim is to explore the kinematic connection of its intermediate to old stellar populations with that obtained from HI observations. Some PNe were found at large galactocentric distances and could therefore represent a trace of past tidal interactions.

Crazy heart: kinematics of the “star pile” in Abell 545

We study the structure and internal kinematics of the "star pile" in Abell 545 - a low surface brightness structure lying in the center of the cluster.We have obtained deep long-slit spectroscopy of the star pile using VLT/FORS2 and Gemini/GMOS, which is analyzed in conjunction with deep multiband CFHT/MEGACAM imaging. As presented in a previous study the star pile has a flat luminosity profile and its color is consistent with the outer parts of elliptical galaxies. Its velocity map is irregular, with parts being seemingly associated with an embedded nucleus, and others which have significant velocity offsets to the cluster systemic velocity with no clear kinematical connection to any of the surrounding galaxies. This would make the star pile a dynamically defined stellar intra-cluster component. The complicated pattern in velocity and velocity dispersions casts doubts on the adequacy of using the whole star pile as a dynamical test for the innermost dark matter profile of the cluster. This status is fulfilled only by the nucleus and its nearest surroundings which lie at the center of the cluster velocity distribution.

Tectonic implications of transtensional supradetachment basin development in an extension‐parallel transfer zone: the Kocaçay Basin, western Anatolia, Turkey

ABSTRACTThe Kocaçay Basin (KÇB) is a key area in western Anatolia – a well‐known extended terrane where regional segmentation has received limited attention – for investigating strike‐slip faults kinematically linked to detachment faults. In this paper, we present results of an integrated sedimentologic, stratigraphic, and structural study of Miocene alluvial fan/fan‐delta/lacustrine deposits that accumulated in the KÇB, a NE‐trending basin with connections to the Menderes Metamorphic Core Complex (MCC). We mapped and evaluated most of the key faults in the KÇB, many for the first time, and recognised different deformation events in the study area near the E margin of the MCC. We also present field evidence for kinematic connections between low‐angle normal and strike‐slip faults which were developed in an intermittently active basement‐involved transfer zone in western Anatolia. We find that the KÇB contains a detailed record of Miocene transtensional sedimentation and volcanism that accompanied exhumation of the MCC. Structural data reveal that the basin was initially formed by transtension (D1 phase) and subsequently uplifted and deformed, probably as a result of early Pliocene wrench‐ to extension‐dominated deformation (D2 phase) overprinted by Plio‐Quaternary extensional tectonics (D3 phase). These results are consistent with progressive deformation wherein the axis of maximum extension remained in the horizontal plane but the intermediate and maximum shortening axes switched position in the vertical plane. Combining our results with published studies, we propose a new working hypothesis that the KÇB was a transtensional supradetachment basin during the Miocene. The hypothesis could provide new insights into intermittently active extension‐parallel zone of weakness in western Anatolia.These results also suggest that the termination of low‐angle normal fault systems within an extension parallel transfer zone may have resulted in a transtensional depressions which are different from classical supradetachment basins with respect to the sedimentation and deformational pattern of the basin infills.

The kinematic connection between galaxies and dark matter haloes

Using estimates of dark halo masses from satellite kinematics, weak gravitational lensing, and halo abundance matching, combined with the Tully-Fisher and Faber-Jackson relations, we derive the mean relation between the optical, V_opt, and virial, V_200, circular velocities of early- and late-type galaxies at redshift z~0. For late-type galaxies V_opt ~ V_200 over the velocity range V_opt=90-260 km/s, and is consistent with V_opt = V_maxh (the maximum circular velocity of NFW dark matter haloes in the concordance LCDM cosmology). However, for early-type galaxies V_opt \ne V_200, with the exception of early-type galaxies with V_opt simeq 350 km/s. This is inconsistent with early-type galaxies being, in general, globally isothermal. For low mass (V_opt < 250 km/s) early-types V_opt > V_maxh, indicating that baryons have modified the potential well, while high mass (V_opt > 400 km/s) early-types have V_opt < V_maxh. Folding in measurements of the black hole mass - velocity dispersion relation, our results imply that the supermassive black hole - halo mass relation has a logarithmic slope which varies from ~1.4 at halo masses of ~10^{12} Msun/h to ~0.65 at halo masses of 10^{13.5} Msun/h. The values of V_opt/V_200 we infer for the Milky Way and M31 are lower than the values currently favored by direct observations and dynamical models. This offset is due to the fact that the Milky Way and M31 have higher V_opt and lower V_200 compared to typical late-type galaxies of the same stellar masses. We show that current high resolution cosmological hydrodynamical simulations are unable to form galaxies which simultaneously reproduce both the V_opt/V_200 ratio and the V_opt-M_star (Tully-Fisher/Faber-Jackson) relation.

Evidence for an active shear zone in southern Nevada linking the Wasatch fault to the Eastern California shear zone

Previous studies have shown that ~5% of the Pacifi c‐North America relative plate motion is accommodated in the eastern part of the Great Basin (western United States). Near the Wasatch fault zone and other nearby faults, deformation is currently concentrated within a narrow zone of extension coincident with the eastern margin of the northern Basin and Range. Farther south, the pattern of active deformation implied by faulting and seismicity is more enigmatic. To assess how present-day strain is accommodated farther south and how this relates to the regional kinematics, we analyze data from continuous global positioning system (GPS) stations and model the strain rate tensor fi eld using the horizontal GPS velocities and earthquake focal mechanisms. The results indicate an ~100-km-wide zone of ~3.3 mm/yr extension at 40.5°N that broadens southward from the Wasatch fault zone to a width of >400 km at 36°N. This broadening involves at least one zone of localized extension in northwestern Arizona that encroaches into the southwestern plateau, and an eastnortheast‐trending sinistral shear zone (the Pahranagat shear zone) through southern Nevada. This shear zone may accommodate as much as 1.8 mm/yr, and is a key feature that enables westward transfer of extension, thereby providing a kinematic connection between the Wasatch fault zone and the Eastern California shear zone.

Geometry of a mechanism with a higher pair in the form of two elliptical tori

This paper presents one of the problems of kinematic analysis of one degree of freedom single-loop spatial mechanism. The problem lies in geometric modeling of mechanisms in such a manner that a model may cover as many structures which include the most common kinematic connection of links as possible. As a result of this approach, a model of a three-link mechanism with a higher kinematic pair consisting of two elliptical tori was obtained. Particular cases of this model are kinematic structures which, after meeting some conditions, become models of mechanisms with revolute, prismatic, cylindrical, spherical pairs or universal joint. In this way, a model of such a mechanism was created where detailed mechanisms are obtained through a change of parameter values.

Variety and connectivity in kinematic chains

Abstract The enumeration of kinematic chains, also known as number synthesis, has been used for at least the past four decades as a means of finding better mechanisms for some predefined purpose. In practice, however, enumeration can be difficult to implement since the number of kinematic chains generated is often too large to manually consider the individual merits of each chain. For this reason, the concepts of variety and connectivity can be used to classify kinematic chains according to the constraints required as described in the literature. In this regard, this paper presents three new results. First, a redefinition of the concepts of variety and connectivity in an algorithmic form is introduced. Second, a set of important relations between connectivity and variety, introduced by Tischler et al. in [C.R. Tischler, A.E. Samuel, K.H. Hunt, Kinematic chains for robot hands: Part 2 kinematic constraints, classification, connectivity, and actuation, Mechanism and Machine Theory 30 (8) (1995) 1217–1239] as conjectures lacking formal proofs, are stated as theorems in this paper and formally proved. Finally, a new algorithm is proposed for the computation of the variety of a kinematic chain; this algorithm includes other parameters such as connectivity and redundancy.

Star Formation Across the Taffy Bridge: UGC 12914/15

We present Berkeley-Illinois-Maryland Association (BIMA) two-field mosaic CO (1–0) images of the Taffy galaxies (UGC 12914/15), which show the distinct taffy-like radio continuum emission bridging the two spiral disks. Large amounts of molecular gas (1.4 × 1010 M⊙, using the standard Galactic CO-to-H2 conversion applicable to Galactic disk giant molecular clouds) were clearly detected throughout the taffy bridge between the two galaxies, which, as in the more extreme case of H I, presumably results from a head-on collision between the two galaxies. The highest CO concentration between the two galaxies corresponds to the Hα source in the taffy bridge near the intruder galaxy UGC 12915. This H II region is also associated with the strongest source of radio continuum in the bridge and shows both morphological and kinematic connections to UGC 12915. The overall CO distribution of the entire system agrees well with that of the radio continuum emission, particularly in the taffy bridge. This argues for the star formation origin of a significant portion of the radio continuum emission. Compared with the H I morphology and kinematics, which are strongly distorted owing to the high-speed collision, CO better defines the orbital geometry and impact parameter of the interaction, as well as the disk properties (e.g., rotation, orientation) of the progenitor galaxies. Based on the 20 cm–to–CO ratio maps, we conclude that the starburst sites are primarily located in UGC 12915 and the Hα source in the bridge and show that the molecular gas in the taffy bridge is forming into stars with star formation efficiency comparable to that of the target galaxy UGC 12914 and similar to that in the Galactic disk.

An automated search for compact high–velocity clouds in the Leiden/Dwingeloo Survey

We describe an automated search through the Leiden/Dwingeloo Hi Survey (LDS) for high-velocity clouds north of= 28. From the general catalog we extract a sample of relatively small (less than about 8) and isolated high-velocity clouds, CHVCs: anomalous-velocity Hi clouds which are sharply bounded in angular extent with no kinematic or spatial connection to other Hi features down to a limiting column density of 1:5 10 18 cm 2 . This column density is an order of magnitude lower than the critical Hi column density,2 10 19 cm 2 , (e.g. Maloney 1993) where the ionized fraction is thought to increase dramatically due to the extragalactic radiation field. As such, these objects are likely to provide their own shielding to ionizing radiation. Their small angular size, of less than about 1 FWHM, might then imply substantial distances, since the partially ionized Hi skin in a power-law ionizing photon field has a typical exponential scale-length of 1 kpc (e.g. Corbelli & Salpeter 1993). The automated search algorithm has been applied to the HIPASS and to the Leiden/Dwingeloo data sets. The results from the LDS are described here; Putman et al. (2002) describe application of this algorithm to the HIPASS material. We identify 67 CHVCs in the LDS which satisfy stringent requirements on isolation, and an additional 49 objects which satisfy somewhat less stringent requirements. Independent confirmation is available for all of these objects, either from earlier data in the literature or from new observations made with the Westerbork Synthesis Radio Telescope and reported here. The catalog includes 54 of the 65 CHVCs listed by Braun & Burton (1999) on the basis of a visual search of the LDS data.

The Kinematic Connection between absorbing Gas toward QSOs and Galaxies at Intermediate Redshift

We present complementary data on five intermediate-redshift (0.44 ? z ? 0.66) Mg II-absorbing galaxies, combining high spatial resolution imaging from the Hubble Space Telescope, high-resolution quasi-stellar object (QSO) spectroscopy from the Keck High Resolution Echelle Spectrometer, and galaxy kinematics from intermediate-resolution spectroscopy using the Keck Low-Resolution Imaging Spectrometer. These data allow a direct comparison of the kinematics of gas at large galactocentric impact parameters with the galaxy kinematics obtained from the faint galaxy spectroscopy. All five galaxies appear to be relatively normal spirals, with measured rotation curves yielding circular velocities in the range 100 ? vc ? 260 km s-1. The QSO sight lines have projected impact parameters to the absorbing galaxies in the range 14.5 h-1 kpc ? d ? 75 h-1 kpc; the galaxies have inclination angles with respect to the line of sight ranging from 40? to 75?. We find that in four of the five cases examined, the velocities of all of the Mg II-absorption components lie entirely to one side of the galaxy systemic redshift. The fifth case, for which the galaxy is much less luminous than the other four, has narrow absorption centered at zero velocity with respect to systemic, despite having the largest disk inclination angle in the sample. These observations are consistent with rotation being dominant for the absorbing-gas kinematics; however, the total range of velocities observed is inconsistent with simple disk rotation in every case. Simple kinematic models that simultaneously explain both the systemic offset of the absorbing material relative to the galaxy redshifts and the total velocity width spanned by the absorption require either extremely thick rotating gas layers, rotation velocities that vary with z-height above the extrapolation of the galactic plane, or both. In any case, our small sample suggests that rotating halo gas is a common feature of intermediate-redshift spiral galaxies and that the kinematic signature of rotation dominates over radial infall or outflow even for gas well away from the galactic plane. We discuss possible explanations for this behavior and compare our observations with possible local analogs.

NH3in the Central 10 pc of the Galaxy. I. General Morphology and Kinematic Connections between the Circumnuclear Disk and Giant Molecular Clouds

New Very Large Array images of NH3 (1, 1), (2, 2), and (3, 3) emission in the central 10 pc of the Galaxy trace filamentary streams of gas, several of which appear to feed the circumnuclear disk (CND). The NH3 images have a spatial resolution of 165 × 145 and have better spatial sampling than previous NH3 observations. The images show the southern streamer, 50 km s-1 cloud, and new features including a western streamer, 6 pc in length, and a ridge, which connects to the CND. NH3 (3, 3) emission is very similar to 1.2 mm dust emission, indicating that NH3 traces column density well. Ratios of the NH3 (2, 2) to (1, 1) line intensities give an estimate of the temperature of the gas and indicate high temperatures close to the nucleus and CND. The new data cover a velocity range of 270 km s-1, including all velocities observed in the CND, with a resolution of 9.8 km s-1. Previous NH3 observations with higher resolution did not cover the entire range of velocities seen in the CND. The large-scale kinematics of the CND do not resemble a coherent ring or disk. We see evidence for a high-velocity cloud within a projected distance of 50'' (2 pc), which is only seen in NH3 (3, 3) and is likely to be hot. Comparison to 6 cm continuum emission reveals that much of the NH3 emission traces the outer edges of Sagitarrius A East and was probably pushed outward by this expanding shell. The connection between the northern ridge (which appears to be swept up by Sgr A East) and the CND indicates that Sgr A East and the CND are in close proximity to each other. Kinematic evidence for these connections is presented in this paper, while the full kinematic analysis of the central 10 pc will be presented in our next paper.

Container spaces and functional features for top-down 3D layout design

Although there have been many advances in computer-aided modelling techniques and representations of mechanical parts, there are areas where exact modelling is a handicap. One of these is 3D layout design. Here, simpler models are useful for initial design sketches to verify kinematic behaviour and organise product structure before the detailed component design phase begins. A commitment to exact, or close approximational geometry too early can imply a commitment to form before functionality has been finalised. This paper describes a system for top-down 3D layout design based on simple conceptual elements which can be used as a basis for visualisation, discussion, definition of product structure and kinematic functionality in the conceptual design phase before the embodiment or detailing begins. This tool forms a bridge between the abstract nature of the conceptual design phase and the geometric nature of the embodiment phase. The 3D layout module uses design spaces with simple geometry and kinematic connections to represent a product. The design spaces act as containers or envelopes within which the final component design is to be realised. The kinematic connections allow the behaviour of the product to be simulated to gain more information (such as overall component dimensions and areas of potential collisions) for the detailed design phase. In addition the paper describes the design process based on the proposed 3D layout design system and contrasts this with the traditional design process. An industrial case study is presented to illustrate the following advantages of the proposed approach: (i) the design process proceeds faster because unnecessary layout parameter and constraint modifications are avoided since kinematic functionality verification precedes the detail design, (ii) the design process can produce better designs since alternative solution principles can be explored early in the design process. Theoretical issues are discussed concerning kinematic constraint inheritance during design space decomposition and concerning computer support for non-rigid design spaces.

A Procedure of Mechanical Testing of Materials in Installations with Screw Loading Devices

We present a new engineering solution of the problem of smooth realization of a prescribed law of loading of a specimen under extreme conditions with the help of a screw loading device. The new idea realized in the structure of the screw loading device is to use the kinematic connection of the screw and nut with separate drives. We improve the mode of operation of the device by applying the unidirectional rotation of the screw and nut with different angular velocities. The specialized system of automatic control over the screw loading device enables one to load the specimen without the appearance of backlashes in the power kinematic chain and nonsmooth axial motion of the screw at strain rates close to zero.

Optimal control for principal kinematic systems on lie groups

Abstract In this paper we present a simplified formulation of the necessary conditions for optimal controls of principal kinematic systems evolving on Lie groups. This class of systems is particularly meaningful because a number of different types of locomotion systems, such as kinematic snakes, paramecia, inchworms, mobile carts, and even the falling cat, can be represented in this form. Furthermore, it is shown that for systems on Abelian Lie groups, the equations describing the optimal control inputs take on an even simpler form, based purely on the curvature of the kinematic connection describing the locomotion. These ideas are presented with several examples, including the cylinder (paramecium) swimming at low Reynolds' number and a normal form for TV-trailer systems.

Kinematic chains for robot hands—II. Kinematic constraints, classification, connectivity, and actuation

The work in this paper follows on from Part 1. We now consider the specific example of robot hands and identify several kinematic constraints of these devices. The method for number synthesis of kinematic chains in Part 1 is applied in several different ways in order to synthesise chains suitable for application as robot hands; several examples of the structures so found are presented. So as to identify those kinematic chains that are more promising than others, the new concept of minimal sets of kinematic chains is defined. Another new concept, the variety of a kinematic chain, is defined and used to make generalisations about relative connectivity within kinematic chains, which has application in the selection of actuated pairs. Fractionation of kinematic chains is reviewed in light of the concept of variety. The work presented here has application far beyond the number synthesis of alternative structures for robot hands.

Late Jurassic blueschist facies pebbles from the Western Carpathian orogenic wedge and paleostructural implications for Western Tethys evolution

In spite of the absence of ophiolitic slices at the surface, some traces of the lost Tethys ocean are recorded along the Pieniny Klippen Belt (PKB), a narrow décollement thrust system sutured at the transpressive boundary between the Outer and Inner Carpathians. The enigmatic precollisional evolution of Western Carpathians can be deciphered from some late Albian to Campanian flysch conglomerates which display chrome spinel grains, ophiolitic detritus and pebbles of blueschist facies tholeiitic metabasalts yielding a 40Ar/39Ar plateau age of 155.4±0.6 Ma. Other detrital components are represented by extrabasinal pebbles of limestones, arc volcanics, and igneous to metamorphic basement rocks from southern sources. Our results suggest a markedly northward extension of the sublongitudinal Triassic Vardar (Meliata) Ocean and its subduction since the late Middle Jurassic, supposedly balanced westward by coeval spreading in the Ligurian‐Piedmont basin of the Apennine‐Western Alpine Tethys. A lateral kinematic connection between these diachronous and roughly parallel Tethys branches was provided on the north by a left‐lateral east‐west trending shear zone running from the Swiss‐Austrian Penninic domain to the Northern Carpathians. This reconstruction replaces the classic model of two paired North Penninic and South Penninic oceanic basins and eastern homologues with the Briançonnais‐Hochstegen and Czorstin microcontinents in between. The Late Jurassic‐Early Cretaceous evolution of the Carpathian active margin was characterized by subduction metamorphism and accretion of a wide orogenic wedge; in this time, the shallowing to deeply subsiding basins inferred from facies analyses on the sedimentary units of the PKB were likely floored by individual sections of the growing wedge. Later, some exhuming blueschist ophiolitic units of the wedge were uplifted to the surface and functioned in the Albian‐Campanian as an “exotic ridge” supplying clasts to the forearc basin. Finally, the colliding wedge became a cryptic paleostructure when, since the latest Cretaceous, it disappeared beneath the Inner Carpathian orogenic lid and was incorporated within the eastward moving infrastructure of the Carpathian orocline.