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A unified dynamic model for locomotion and manipulation of a snake-like robot based on differential geometry

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Science China(Information Sciences) 2011年第2期54卷 318-333页

作者： WANG ZhiFeng1,3, MA ShuGen1,2, LI Bin1 & WANG YueChao1 1State Key Laboratory of robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, China 2department of robotics, ritsumeikan university, Shiga-ken 52.-8577, japan 3Graduate university of Chinese Academy of Sciences, Beijing 100039, China 1. State Key Laboratory of robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China3. Graduate University of Chinese Academy of Sciences Beijing 100039 China2. Department of Robotics Ritsumeikan University Shiga-ken 525-8577 Japan

A snake-like robot, whose body is a seried-wound articulated mechanism, can move in various environments. In addition, when one end is fixed on a base, the robot can manipulate objects. A method of dynamic modeling for locomotion and manipulation of the snake-like robot is developed in order to unify the dynamic equations of two states. The transformation from locomotion to manipulation is a mechanism reconfiguration, that is, the robot in locomotion has not a fixed base, but it in manipulation has one. First, a virtual structure method unifies the two states in mechanism (e.g., an embedding in the configuration space); second, the product-of-exponentials formula describes the kinematics; third, the dynamics of locomotion and manipulation are established in a Riemannian manifold; finally, based on the analysis of the dynamic model, the dynamics of manipulation can be directly degenerated from those of locomotion, and this degeneration relation is proved through using the Gauss equations. In the differential geometry formulation, this method realizes the unification of the dynamics of locomotion and manipulation. According to a geometrical point of view, the unified dynamic model for locomotion and manipulation is considered as a submanifold problem endowed with geometric meaning. In addition, the unified model offers an insight into the dynamics of the snake-like robot beyond the dynamic model separately established for locomotion or manipulation.

关键词： snake-like robot dynamics unified model differential geometry locomotion manipulation

Oxidation of Hastelloy-XR Alloy for Corrosion-Resistant Glass-Coating

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Journal of Materials Science & Technology 2003年第1期19卷 19-22页

作者： Rong TU and Takashi GOTOInstitute for Materials Research, Tohoku university, Sendai 980-8577, japan Inst. for Mat. Res. Tohoku Univ. Sendai 980-8577 Japan

The oxidation behavior of Hastelloy-XR alloy was investigated to obtain the optimum surface condition for corrosion-resistant glass-coatings. The surface morphology of oxide scales changed significantly with variation of temperatureand oxygen partial pressure (po2 ). The oxidation kinetics was mainly parabolic independent of oxidation *** oxide scales were consisted of inner Cr2O3 and outer spinel layers. The phase component of spinel layers wereMn1.5Cr1.5O4 and (Mn,Ni)(Cr,Fe)2O4 for the oxygen partial pressures po210 kPa, *** optimum oxidation condition to obtain an oxide scale for well-adhered glass-coating to the substrate was 1248 Kand po2 =0.01 kPa for the oxidation time of 43 ks.

关键词： Oxidation Hastelloy-XR alloy Glass coating

Shear Strength Behavior of Two Landfill Clay Liners

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Journal of China university of Geosciences 2002年第3期13卷 260-265页

作者： Jian Wenxing Engineering Faculty, China university of Geosciences, Wuhan 430074 Masashi Kamon Toru Inui department of Global Environmental Engineering, Graduate School of Engineering, Kyoto university,Kyoto, 606 8501, japan Takeshi Katsumi department of Civil Engineering, ritsumeikan university, kusatsu, Shiga, 52. 8577, japan Engineering Faculty China University of Geosciences Wuhan 430074 department of Global Environmental Engineering Graduate School of Engineering Kyoto UniversityKyoto 606-8501 Japan department of Civil Engineering Ritsumeikan University Kusatsu Shiga 525-8577 Japan

Direct shear tests were conducted to obtain both the shear strength ofcompacted clay liners (CCLs) specimens and the interface shear strength between compacted clay linerand base soil. These experiments were conducted under the conditions of five different watercontents. The experimental results show that shear strength of both CCLs and CCLs/base interfacedecreases with the increase in the water content of CCLs and base soil. In addition, the considerateconcentration of NaCl in leachate has no deteriorating effect on the shear strength of *** shear tests were also conducted on clay liner specimens to obtain total and effective shearstrength under a fast compression. The shear strength parameters with total stress are φ=18. 5°and c=30 kPa for clay-bentonite, and φ=48. 5° and c=90 kPa for sand-bentonite and those witheffective stress are φ'= 27. 2° and c'=25 kPa for clay-bentonite, and φ'=35° and c'=100 kPa forsand-bentonite, respectively. These results indicate that the compacted clay-bentonite shows normalconsolidation, but that the compacted sand-bentonite exhibits over-consolidation.

关键词： shear strength behavior direct shear test CU triaxial compression test compacted clay liner landfill

Spin Trapping of the Phosphorus-centered Radicals Generated from Hydrogen Abstraction Reaction by 2,2-Diphenyl-1-picrylhydrazyl

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Chemical Research in Chinese Universities 2000年第4期16卷 313-319页

作者： Yoshimi Sueishi and Yuko Nishihara (department of Chemistry, Faculty of Science, Okayama university, 3-1-1 Tsushima Naka, Okayama 700-8530, japan) Okayama Univ Fac Sci Dept Chem Okayama 7008530 Japan

Two kinds of the phosphorus-centered radicals produced from hydrogen atomion by 2, 2-diphenyl-1-picrylhydrazyl(DPPH were trapped by N-tert-butyl-α-phenylnitrone(PBN) and 5, 5-dimethyl-1-pyrroline N-oxide (DMPO), and investigated by means of EPR spectroscopy. The spin adducts with a characteristic hyperfine coupling constant(hfcc) caused by a phosphorus atom were observed. Based on the hfcc values caused by the phosphorus and hydrogen atoms, the con formational positions of the adducts trapped by PBN and DMPO are discussed.

关键词： EPR Spin trap Phosphorus-centered radical

CONVERGENCE OF CHORIN-MARSDEN FOR MULA FOR THENAVIER-STOKES EQUATIONS ON CONVEX DOMAINS

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Journal of Computational Mathematics 1999年第1期17卷 73-88页

作者： Lung-an Ying(Research institute for Mathematical Sciences, Kyoto university, japan department of Mathematics, Peking university, Beijing 100871, China) Peking Univ Dept Math Beijing 100871 Peoples R China Kyoto Univ Math Sci Res Inst Kyoto Japan

We prove the convergence of the Chorin-Marsden product formula for solving the initial-boundary value problems of the Navier-Stokes equations on convex domains. As a particular case we consider the case of the half pl... 详细信息

关键词： Navier Stokes equation vortex method fractional step method convergence

DETECTION OF TRANSIENT SIGNAL USING THE DISCRETE WAVELET TRANSFORM

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国防科技大学学报 1995年第3期17卷 114-118,125页

作者： Liu Zheng(department of Information Electronics,Faculty of Engineering,Nagoya university, Nagoya, 464,japan)

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关键词：信号检测瞬态信号 DWT

Study on the two and three-parameter working stability regions of 3Y-TZP suspension

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Science China(Technological Sciences) 2006年第5期49卷 547-568页

作者： CHEN Youqiang1, 2, ZHANG Xinni3, CHEN Sha’ou3 & QI Ping3 1. department of Chemistry, Qingdao university, Qingdao 266071, China 2. department of Chemistry, Tsinghua university, Beijing 100084, China 3. department of Physics, Qingdao university, Qingdao 266071, China 1. department of Chemistry Qingdao University Qingdao 266071 China 2. department of Chemistry Tsinghua University Beijing 100084 China 3. department of Physics Qingdao University Qingdao 266071 China

We determined the variation tendency of viscosity (η) at various solids load- ing (α) for 3Y-TZP suspension as a function of dispersant concentration (Cw) using vis- cosity measurement, measured the diameter of particles as a function of Cw in very dilute suspension using light scattering method, and obtained the surface features of the sedi- ment of suspension with different Cw using SEM. We also discussed the influence of the microstructure of adsorbed polymer layers on particles and their interactions in the dis- persing medium on the stability of suspension. Then two different stable states and two different unstable states for 3Y-TZP suspension were given. Accordingly, the (Cw, η), (Cw, α), and (α, η) two-parameter, and (Cw, α, η) three-parameter stability maps were con- structed. Based on the DLVO theory calculations, the dispersant concentration, particle distance (r), and interparticle potential energy (VT) maps with various solids loading for 3Y-TZP aqueous suspension were also constructed. In (Cw, r) two-parameter coordinate system, the stable motion region map for particles was established. The Cw, α, and VT,max (the highest potential energy) surface of the potential barrier map was obtained through calculation and simulation on the basis of the surfaces of Cw, r, VT maps introduced above. The (Cw, α) two-parameter stability map was then obtained from the Cw, α, VT,max map. The results showed that this theoretical map can qualitatively prove the experimentally obtained results—the existence of different dispersed states of particles in suspension system and the variation tendency of suspension stability with changing each parame- ter—were reasonable.

关键词： 3Y-TZP, suspension, stability, DLVO theory, interparticle potential energy.

Solidification of Municipal Solid Waste Incineration FlyAsh with Cement and Its Leaching Behaviors of Heavy Metals

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Journal of Wuhan university of Technology(Materials Science) 2003年第1期18卷 55-60,68页

作者：余其俊 SouthChinauniversityofTechnology

The solidifying effect of cement addition on municipal solid waste incineration fly ash (MSWFA for short,collected from the gas exhaust system of MSW incinerator),the interaction of MSWFA with cement and water and the leaching of heavy metals from cement solidified MSWFA are *** main results show that:(1) when MSWFA is mixed with cement and water,H 2 evolution,the formation and volume expansion of AFt will take place,the volume expansion can be reduced by ground rice husk ash addition;(2) heavy metals do leach from cement solidified MSWFA and at lower pH more leaching will occur;(3) compared with cement-solidified fly ash,the leachate of solidified MSWFA is with higher heavy metal contents;(4) with the increment of cement addition leached heavy metals are decreased;and (5) concentrations of Zn,Mn,Cu and Cd in all the leachates can meet the relevant Standards of japan,but as the regulations for soil and groundwater protection of japan are concerned,precautions against the leaching of Pb,Cl - and Cr 6+ and so on are needed.

关键词： municipal solid waste fly ash leaching heavy metals environmental impact

Macro- and microstructural changes in hydrogenated TiMn_2 and Ta

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中国有色金属学会会刊：英文版 2002年第4期12卷 695-701页

作者： S. Semboshi, N. Masahashi, S. Hanada (Institute for Materials Research, Tohoku university, Sendai 980 8577, japan) Institute for Materials Research Tohoku University 日本 Sendai 980-8577

Binary TiMn 2 alloys with various compositions were arc melted in an Ar atmosphere. These alloys consist of TiMn 2 and a small amount of TiMn depending on alloy composition. Annealed Ti 59.4% Mn exhibits the greatest capacity for hydrogen absorption and the smallest degradation of capacity during repeated hydrogen absorption and desorption. No apparent macro and microstructural changes are observed in Ti 59.4% Mn by repeated hydrogenation of 30 cycles. At Mn content higher than 59.4% Mn, the formation of nano sized Ti hydride and the lattice expansion due to retained interstitial hydrogen were confirmed in repeatedly hydrogenated alloys. Pulverized powders were refined in all the alloys with increasing the number of repeated hydrogenation cycles. Many onion like cracks are introduced in annealed pure Ta with 100?μm equi axed grains by holding at 1?473?K followed by furnace cooling to room temperature in a hydrogen atmosphere, but no crack is observed after holding at 1?473?K in a hydrogen atmosphere followed by furnace cooling in an Ar atmosphere. It is concluded that the surface activation is attained in a hydrogen atmosphere at 1?473?K and multiple cracking occurs by absorbing a large amount of hydrogen at lower temperature. Volume expansion and dislocations generated by hydrogenation and hydride formation are responsible for multiple cracking. Hydrogen induced multiple cracking in Ta occurs in the following sequence: hydrogen absorption, lattice expansion, hydride formation, and crack nucleation and propagation. Powder fabrication of Ta by hydrogenation is discussed in comparison with the hydrogen pulverization of intermetallic alloys.

关键词：宏观结构显微结构贮氢合金 TiMn2 钽