检索结果-南通市图书馆

Image-based autonomous navigation of Hayabusa2 using artificial landmarks: The design and brief in-flight results of the first landing on asteroid Ryugu

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Astrodynamics 2020年第2期4卷 89-103页

作者： Naoko Ogawa Fuyuto Terui Yuya Mimasu Kent Yoshikawa Go Ono Seiji Yasuda Kota Matsushima Tetsuya Masuda Hiroki Hihara Junpei Sano Takashi Matsuhisa Satoshi Danno manabu yamada Yasuhiro Yokota Yuto Takei Takanao Saiki Yuichi Tsuda Japan Aerospace Exploration Agency Sagamihara252-5210Japan NEC Corporation Fuchu183-8501Japan NEC Space Technologies Ltd.Fuchu183-8551Japan Systems Engineering Consultants Co. Ltd.Tokyo158-0097Japan Planetary Exploration Research Center Chiba Institute of TechnologyNarashino275-0016Japan

Hayabusa2 is an asteroid sample return mission carried out by the Japan Aerospace Exploration *** spacecraft was launched in 2014 and arrived at the target asteroid Ryugu on June 27,*** the 1.5-year proximity phase,several critical operations(including two landing/sampling operations)were successfully *** were based on autonomous image-based descent and landing *** paper describes an imagebased autonomous navigation scheme of the Hayabusa2 mission using artificial landmarks named target markers(TMs).Its basic algorithm,and the in-flight results of the first touchdown and its rehearsal,are shown.

关键词： Hayabusa2 Ryugu image-based navigation target marker tracking

The deep-space multi-object orbit determination system and its application to Hayabusa2’s asteroid proximity operations

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Astrodynamics 2020年第4期4卷 377-392页

作者： Hiroshi Takeuchi Kent Yoshikawa Yuto Takei Yusuke Oki Shota Kikuchi Hitoshi Ikeda Stefania Soldini Naoko Ogawa Yuya Mimasu Go Ono Fuyuto Terui Naoya Sakatani manabu yamada Toru Kouyama Shingo Kameda Takanao Saiki Yuichi Tsuda Institute of Space and A stronautical Science Japan A erospace Exploration AgencySagamihara 252-5210Japan The Graduate University for Aduanced Studies Hayama 240-0193Japan Research and Development Directorate Japan Aerospace Exploration AgencySagamihara 252-5210Japan University of Liverpool Liverpool L693BXUK Chiba Institute of Technology Narashino 275-0016Japan National Institute of Aduanced Industrial Science and Technology Koto-ku 135-0064Japan Rikkyo University Toshima-ku 171-8501Japan

The deep-space multi-object orbit determination system(DMOODS)and its application in the asteroid proximity operation of the Hayabusa2 mission are *** was developed by the Japan Aerospace Exploration Agency(JAXA)for the primary purpose of determining the trajectory of deep-space spacecraft for JAXA’s planetary *** weighted least-squares batch filter is used for the orbit estimator of *** orbit estimator supports more than 10 data types,some of which are used for relative trajectory measurements between multiple space objects including natural satellites and small *** system consists of a set of computer programs running on Linux-based consumer PCs on the ground,which are used for orbit determination and the generation of radiometric tracking data,such as delta differential one-way ranging and doppler tracking *** the asteroid proximity phase of Hayabusa2,this system played an essential role in operations that had very strict navigation requirements or operations in which few optical data were obtained owing to special constraints on the spacecraft attitude or distance from the *** example is orbit determination during the solar conjunction phase,in which the navigation accuracy is degraded by the effect of the solar *** large range bias caused by the solar corona was accurately estimated with DMOODS by combining light detection and ranging(LIDAR)and ranging measurements in the superior solar conjunction phase of *** the orbiting operations of target markers and the MINERVA-II2 rover,the simultaneous estimation of six trajectories of four artificial objects and a natural object was made by *** type of simultaneous orbit determination of multi-artificial objects in deep-space has never been accomplished before.

关键词： orbit determination optical navigation gravity measurements superior solar conjunction delta differential one-way ranging(delta-DOR)

Orbit insertion strategy of Hayabusa2’s rover with large release uncertainty around the asteroid Ryugu

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Astrodynamics 2020年第4期4卷 309-329页

作者： Yusuke Oki Kent Yoshikawa Hiroshi Takeuchi Shota Kikuchi Hitosi Ikeda Daniel JScheeres Jay WMcMahon Junichiro Kawaguchi Yuto Takei Yuya Mimasu Naoko Ogawa Go Ono Fuyuto Terui manabu yamada Toru Kouyama Shingo K ameda Kazuya Yoshida Kenji Nagaoka Tetsuo Yoshimitsu Takanao Saiki Yuichi Tsuda Japan A erospace Exploration Agency T'sukuba 305-8505Japan Japan Aerospace Exploration Agency Sagamihara 252-5210Japan University of Colorado BoulderCO 80309USA Planetary Exploration Research Center Chiba Institute of TechnologyNarashino 275-0016Japan National Institute of Aduanced Industrial Science and Technology Koto-ku 135-0064Japan Rikkyo University Toshima-ku 171-8501Japan Department of A erospace Engineering Tohoku UniversitySendai 980-8579Japan Kyushu Institute of Technology Kitakyusyu 804-8550Japan

This paper describes the orbit design of the deployable payload Rover 2 of MINERVA-II,installed on the Hayabusa2 *** Rover 2 did not have surface exploration capabilities,the operation team decided to experiment with a new strategy for its deployment to the *** rover was ejected at a high altitude and made a semi-hard landing on the surface of the asteroid Ryugu after several *** on the orbital analysis around Ryugu,the expected collision speed was tolerable for the rover to function *** the rover could not control its position,its motion was entirely governed by the initial ***,the largest challenge was to insert the rover into a stable orbit(despite its large release uncertainty),and avoid its escape from Ryugu due to an environment strongly perturbed by solar radiation pressure and gravitational *** study investigates the solution space of the orbit around Ryugu and evaluates the orbit’s robustness by utilizing Monte Carlo simulations to determine the orbit insertion *** analyzing the flight data of the rover operation,we verified that the rover orbited Ryugu for more than one period and established the possibility of a novel method for estimating the gravity of an asteroid.

关键词： solar radiation pressure augmented elliptic Hill three-body problem gravitational irregularity

Motion reconstruction of the small carry-on impactor aboard Hayabusa2

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Astrodynamics 2020年第4期4卷 289-308页

作者： Takanao Saiki Yuya Mimasu Yuto Takei manabu yamada Hirotaka Sawada K azunori Ogawa Naoko Ogawa Hiroshi Takeuchi Akira Miura Yuri Shimaki Koji Wada Rie Honda Yasuhiro Yokota Kei Shirai Naruhisa Sano Hirohito Ohtsuka Go Ono Kent Yoshikawa Shota Kikuchi Chikako Hirose Yukio Yamamoto Takahiro Iwata Masahiko Arakawa Seiji Sugita Satoshi Tanaka Fuyuto Terui Makoto Yoshikawa Satoru Nakazawa Sei-ichiro Watanabe Yuichi Tsuda Japan Aerospace Exploration Agency Sagamihara 252-5210Japan Chiba Institute of Technology Narashino 275-0016Japan Kobe University K obe 657-8501Japan The Graduate University for Aduanced Studies Sagamihara 252-5210Japan Kochi University Kochi 780-8520Japan IHI Aerospace Co. LtdTomioka 370-2398Japan The University of Tokyo Tokyo 113-0033Japan Nagoya University Nagoya 464-8601Japan

Subsurface exploration is one of the most ambitious scientific objectives of the Hayabusa2 mission.A small device called small carry-on impactor(SCI)was developed to create an artificial crater on the surface of asteroid *** enables us to sample subsurface materials,which will provide a window to the *** physical properties of the resulting crater are also useful for understanding the internal structure of *** understanding of the crater and ejecta properties,including the depth of excavation of subsurface materials,requires accurate information on impact *** particular,the impact angle is a critical factor because it greatly influences the size and shape of the *** April 5,2019,the Hayabusa2 spacecraft deployed the SCI at 500 m of altitude above the asteroid *** SCI gradually reduced its altitude,and it shot a 2 kg copper projectile into the asteroid 40 min after *** the position of the released SCI is essential for determining the impact *** study describes the motion reconstruction of the SCI based on the actual operation *** results indicate that the SCI was released with high accuracy.

关键词： small body exploration Hayabusa2 kinetic impact artificial crater motion reconstruction

Correction to: Orbit insertion strategy of Hayabusa2’s rover with large release uncertainty around the asteroid Ryugu

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Astrodynamics 2021年第2期5卷 183-183页

作者： Yusuke Oki Kent Yoshikawa Hiroshi Takeuchi Shota Kikuchi Hitosi Ikeda Daniel J.Scheeres Jay W.McMahon Junichiro Kawaguchi Yuto Takei Yuya Mimasu Naoko Ogawa Go Ono Fuyuto Terui manabu yamada Toru Kouyama Shingo Kameda Kazuya Yoshida Kenji Nagaoka Tetsuo Yoshimitsu Takanao Saiki Yuichi Tsuda Japan Aerospace Exploration Agency Tsukuba305-8505Japan Japan Aerospace Exploration Agency Sagamihara252-5210Japan University of Colorado BoulderCO80309USA Planetary Exploration Research Center Chiba Institute of TechnologyNarashino275-0016Japan National Institute of Advanced Industrial Science and Technology Koto-ku135-0064Japan Rikkyo University Toshima-ku171-8501Japan Department of Aerospace Engineering Tohoku UniversitySendai980-8579Japan Kyushu Institute of Technology Kitakyusyu804-8550Japan

Correction to:Oki,Y.,Yoshikawa,K.,Takeuchi,*** *** insertion strategy of Hayabusa2's rover with large release uncertainty around the asteroid *** 2020,4(4):309-329 https://***/10.1007/s42064-020-0080-y The article“Orbit insertion strategy of Hayabusa2’s rover with large release uncertainty around the asteroid Ryugu”written by Yusuke Oki,Kent Yoshikawa,Hiroshi Takeuchi et al.,was originally published electronically on the publisher’s internet portal(currently SpringerLink)on 05 November 2020 without open *** publication in Volume 4,Issue 4,page 309–329,the author(s)decided to opt for Open Choice and to make the article an open access publication.

关键词： asteroid insertion release

The effect of the 18R-LPSO phase on the fatigue behavior of extruded Mg/LPSO two-phase alloy through a comparative experimental-numerical study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2021年第1期9卷 130-143页

作者： Fabien Briffod Takayuki Shiraiwa manabu Enoki Department of Materials Engineering The University of Tokyo7-3-1 HongoBunkyo-kuTokyo 113-8656Japan

The fatigue behavior of four extruded Mg-Y-Zn alloys containing different volume fractions of long-period stacking ordered(LPSO)grains was investigated through a comparative study combining experiments and crystal plasticity finite element *** controlled low-cycle fatigue experiments were conducted at different strain amplitudes and revealed a limited cyclic hardening in Mg_(89)Zn_(4)Y_(7)alloy or softening in Mg_(99.2)Zn_(0.2)Y_(0.6)and Mg_(97)Zn_(1)Y_(2)alloys.A decrease in the fatigue life against the plastic strain with the increase in LPSO phase volume fraction was observed and was related the limited ductility of extruded LPSO ***-strain hysteresis curves were used to calibrate and validate a crystal plasticity model taking into account twinning and *** interaction of the different phases on the distribution of local micro-mechanical fields at the grain scale was then analyzed on synthetic microstructures under strain-controlled *** twinning activity was predicted in coarse unrecrystallized grains and tended to disappear with the increase in the LPSO phase volume ***-like facets observed in LPSO grains were related to high tensile stress,especially at the Mg/LPSO interface,due to the limited number of deformation mechanisms in LPSO crystal to accommodate out-of-basal plane *** increase of the fatigue limit with the increase in LPSO phase volume fraction was finally associated with the decreasing presence of coarse unrecrystallizedα-Mg grains due to a higher dynamic recrystallization activity during the extrusion process.

关键词： Magnesium alloy Fatigue Long-period stacking ordered phase Crystal plasticity Finite element method

Effect of End Plates on the Performence of a Wells Turbine for Wave Energy Conversion

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2006年第4期15卷 319-323页

作者： manabu Takao Toshiaki Setoguchi YoichiKinoue KenjiKaneko Department of Mechanical Engineering Matsue National College of Technology 14-4 Nishiikuma-choMatsue-shiShimane 690-8518Japan Institute of Ocean Energy Saga University1 Honjo-machiSaga-shiSaga 840-8502Japan Department of Mechanical Engineering Saga University1 Honjo-machiSaga-shiSaga 840-8502Japan

In order to improve the performance of the Wells turbine for wave energy conversion, the effect of end plates on the turbine characteristics has been investigated experimentally by model testing under steady flow conditions. The end plate attached to the tip of the original rotor blade is slightly larger than the original blade profile. The characteristics of the Wells turbine with end plates have been compared with those of the original Wells turbine, i.e., the turbine without end plate. As a result, it has been concluded that the characteristics of the Wells turbine with end plates are superior to those of the original Wells turbine and the characteristics are dependent on the size and position of end plate. Furthermore, the effect of annular plate on the turbine performance, which encircles the turbine and is attached to the tip, was investigated as an additional experiment. However, its device was not effective in improving the turbine characteristics.

关键词： fluid machinery natural energy Wells turbine end plate wave energy conversion ocean energy.

Cubic Spiral Transition Matching G^(2) Hermite End Conditions

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Numerical Mathematics(Theory,Methods and Applications) 2011年第4期4卷 525-536页

作者： Zulfiqar Habib manabu Sakai COMSATS Institute of Information Technology Department of Computer ScienceDefense RoadOff Raiwind RoadLahorePakistan Department of Mathematics&Computer Science Koorimoto 1-21-35Kagoshima 890-0065Japan

This paper explores the possibilities of very simple analysis on derivation of spiral regions for a single segment of cubic function matching positional,tangential,and curvature end *** are curves of monotone curvature with constant sign and have the potential advantage that the minimum and maximum curvature exists at their end ***,spirals are free from singularities,inflection points,and local curvature *** properties make the study of spiral segments an interesting problem both in practical and aesthetic applications,like highway or railway designing or the path planning of non-holonomic mobile *** main contribution is to simplify the procedure of existence methods while keeping it stable and providing flexile constraints for easy applications of spiral segments.

关键词： Path planning spiral cubic Bézier G2 Hermite Computer-Aided Design(CAD) computational geometry

Comparing salinity tolerance in embryonic and larval development of two species of water strider, Aquarius paludum and Gerris latiabdominis （Hemiptera： Gerridae）

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Insect Science 2013年第4期20卷 524-530页

作者： manabu Kishi Tetsuo Harada Kenji Fujisaki Laboratory of Insect Ecology Graduate School of Agriculture Kyoto University Laboratory of Environmental Physiology Faculty ofEducation Kochi University Kochi Japan

Water strider Aquarius paludum （Fabricius） is a cosmopolitan species colonizes mainly freshwater but occasionally brackish habitats throughout the Palearctic and Oriental regions. Water strider Gerris latiabdominis （Miyamoto） is a common species in Japan lives in temporary habitats as freshwater paddy fields. These two species often occur syntopically. We investigated differences in the developmental response to brackish water during embryonic and larval stages between the two species. Eggs were exposed to 0-1.8% NaC1 solutions within 24 h of oviposition. Larvae of G. latiabdominis were exposed to salinities of 0, 0.5%, and 0.9% from the first instar until adult emergence. Limits of NaC1 concentration for hatching were 1.3% and 1.0% for A. paludum and G. latiabdominis, respectively. The hatching rate of G. latiabdominis was lower than that ofA. paludum at salinities 〉0.9%. The period of embryonic development of G. latiabdominis was more prolonged than that ofA. paludum at a given salinity. Although the salinity tolerance of G. latiabdominis was lower than that ofA. paludum, our results suggest G. latiabdominis has the physiological capacity to expand into brackish waters. High and low salinity tolerances of A. paludum and G. latiabdominis, respectively, reflect the relatively wide range of habitat salinities utilized by A. paludum and the relatively restricted habitats preferred by G. latiabdominis. The high salinity tolerance ofA. paludum could be an important factor contributing to their cosmopolitan distribution because high tolerance to salinity means the possibility of them to be dispersed via ocean or sea to other continents and islands.

关键词： embryo larva salinity tolerance water strider