研究者詳細 - 平木　講儒

論文 - 平木　講儒

分割表示 >> ／全件表示78 件中 1 - 78 件目

Attitude Determination and Control System Design for a 3U CubeSat to Monitor Forward Light Scattering over Earth Horizon 査読有り

Mehmet Esit, Kudakweshe Jeje , Ratatamanun Subsinchai , Rodrigo Cordova , Minh Anh Pham , Necmi Cihan Orger , Victor Schulz , Koju Hiraki , Mengu Cho

74 th International Astronautical Congress 2023年10月

Global Trajectory Optimization for Solar-Sail Propelled Mercury Rendezvous and Impact Missions 査読有り

Amirul Fiqri Abdullah, Bernd Dachwald, Renuganth Varatharajoo , Yew-Chung Chak, Koju Hiraki and Letícia Barros

6th International Symposium on Space Sailing 2023年06月

Comparative Study on Trajectory Optimization for Solar Sail Mercury Mission

Mehmet ESIT, Leticia BARROS, Koju HIRAKI

34th International Symposium on Space Technology and Science 2023年06月

Evaluation of Folding-Pattern Designs for Large-Scale Square Solar Sail

Leticia SANTOS LULA BARROS, Koju HIRAKI, Hiroki MIYAGAWA, Mehmet ESIT, Yew-chung CHAK ,Renuganth VARATHARAJOO, Amirul FIQRI ABDULLAH, Bernd DACHWALD

34th International Symposium on Space Technology and Science 2023年06月

Digital streak imaging of compressible flows 査読有り

V. Sridhar, K. Hiraki, S.L. Gai, H. Kleine

Optics and Lasers in Engineering ( Elsevier ) 160 2023年01月

Rotational Motions of Axisymmetric Blunt Body in Different Degrees of Freedom

K. Hiraki, Y. Kuronuma, M. Sakai, H. Kliene

Proceedings of 33rd International Symposium on Space Technology and Science 2022年03月

Electromagnetic Stabilization System Algorithm During Energy Restriction Mode for the Near-Symmetric Satellite 査読有り国際誌

P. Zheliabov, E. Lapkhanov, D. Faizullin, A. Kulabukhov, K. Hiraki

International Review of Aerospace Engineering 15 ( 1 ) 62 - 70 2022年02月

The Experimental Study of Ultra Fine Bubbles in Coolant on Surface Grinding 査読有り

K. Hiraki, M. Sakai, S. Tamaki, T. Watanabe, R. Takada, K. Ushijima

Proceedings of International Conference on Leading Edge Manufacturing in 21st century : LEM21 2021年11月

Effect of Solidity on Efficiency for High-Advance-Ratio Propeller 査読有り

K. Hiraki, H. Kai

Proceedings of 2021 Asia-Pacific International Symposium on Aerospace Technology 2021年11月

Damping Experiments of a Blunt Body with Rough Surfaces 査読有り

K. Hiraki, M. Sakai, H. Kleine

Proceedings of 2021 Asia-Pacific International Symposium on Aerospace Technology 2021年11月

Kite-Flying in High Altitude

HIRAKI Koju, TAKEI Ryosuke, MURAHASHI Reo

The Proceedings of the International Conference on Motion and Vibration Control ( 一般社団法人日本機械学会 ) 2020 ( 0 ) 10109 2020年01月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

<p>In order to investigate the feasibility of high-altitude flight of a kite, the static force balance on a mooring cable and a kite is considered. The kite is treated as a single-point mass and the mooring cable is divided to multiple fragments with mass. First, the kite-flying experiment is carried out to validate the analytical technique. The kite flies at a height of 94m and the measured tensile force is about 12N. Next, the flight at height of 5km is investigated analytically. Normally available polyethylene line can withstand the required load and the flight is shown possible. Moreover, it is shown that the 7km flight is also possible by using ultra-high-strength polyethylene fiber. For a higher-height flight it is not possible in the analyses made here.</p>

DOI： 10.1299/jsmeintmovic.2020.15.10109

CiNii Article

CiNii Research

その他リンク： https://ci.nii.ac.jp/naid/130008057334

Dynamic Motions of Re-Entry Bodies Induced by Rough Surface 査読有り

Koju Hiraki, Akihiro Aoki, Dmytro Faizullin, Harald Kleine

Proceedings of 32nd International Symposium of Space Technology and Science & 9th Nano-Satellite Symposium 2019年06月

Estimating sun vector based on limited in-orbit data 査読有り

Faizullin D., Hiraki K., Cho M.

International Review of Aerospace Engineering 12 ( 2 ) 101 - 108 2019年01月

記述言語：英語掲載種別：研究論文（学術雑誌）

This paper introduces an attitude and orbit determination system, in particular a sun vector determination algorithm, for HORYU-IV nano-satellite by Kyushu Institute of Technology (Kyutech). Usually, nano-satellites cannot use sensors with high specs because of limited budget and onboard space. In order to achieve the required accuracy of attitude determination, estimation algorithms combining different sources of attitude information should be used. One of the HORYU-IV missions has required sun vector information. In order to detect the sun angle, six sun sensors, which have originally been designed and developed by the authors, and five solar panels have been used. However, due to the narrow field of view and to the saturation property of these sensors, the duration of sun detection is quite limited. At a non-detection period, a gyro sensor is used in order to propagate the attitude. However, the sensor has the bias error in its measured value. Hence, the Extended Kalman Filter has been used in order to estimate the sun vector and the bias error of gyro sensors. A simulation result shows that the algorithm can estimate the sun vector in 1deg accuracy.

DOI： 10.15866/irease.v12i2.16189

Scopus

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Simultaneous time-resolved density-sensitive visualization of high-speed flows 査読有り

Kleine H., Hiraki K., Nonaka S.

Proceedings of SPIE - The International Society for Optical Engineering 11051 2019年01月

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

By using two high-speed cameras and a slightly extended visualization setup (typically based on a Toepler system) one can generate two simultaneous time-resolved records of the same flow, where these records can be obtained with different visualization methods, different spatial and different temporal resolutions. This allows one to generate visualizations that can complement each other in various ways and thus yield a considerably increased amount of information on the observed flow.

DOI： 10.1117/12.2523565

Scopus

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Improvement of Efficiency of Darrieus Turbine by Pitch Variation 査読有り

Koju Hiraki, Katsuhiro Henzan, Koju Hifumi

Proceedings of the Thirteenth ISOPE Pacific-Asia Offshore Mechanics Symposium 2018年10月

Improvement of Self-Starting of Darrieus Turbine by Pitch Variation 査読有り

Koju Hiraki, Katsuhiro Henzan

Proceedings of the 4th Asian Wave and Tidal Energy Conferece 2018年09月

Flow Induced Motions observed in Blunt Body with Free Rotational Apparatus in Three Degrees of Freedom 査読有り

K.Hiraki, S.Otomo, A. Aoki, K. Tanaka, H. Kleine

AIAA Aviation Forum 2018年06月

Flow induced motions observed in blunt body with free rotational apparatus in three degrees of freedom 査読有り

Hiraki K., Otomo S., Tanaka K., Faizullin D., Kleine H.

2018 Fluid Dynamics Conference 2018年01月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

For an investigation of the dynamic stability of a blunt body in a wind tunnel, a free rotational apparatus in three degrees of freedom (3-DOF) is developed. This 3-DOF apparatus allows a model to rotate simultaneously about the pitch, yaw and roll axes. With this apparatus dynamic tests are carried out for a blunt in flows of various Mach numbers. In flows below Mach 0.6 the model exhibits oscillations in pitch with an amplitude of more than five degrees. Especially in the flow of Mach 0.3, it shows this oscillation not only in pitch but also in yaw. It should be noted that the model also rotates along its longitudinal axis. In the flow of Mach 0.9 no obvious oscillation is observed. In order to visualize the flow which induces such oscillations and the rotation, a combined technique of schlieren and tufts is applied. From the comparison of the flow visualization images at Mach 0.3 and 0.6, an obvious difference is found in the flow reattachment on the back surface of the model. The results by the differential-pressure measurement supports that the flow reattachment on the back surface of the model happens asymmetrically, and it generates a rolling moment.

DOI： 10.2514/6.2018-3235

Scopus

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Improvement in efficiency of Darrieus turbine by pitch variation 査読有り

Hiraki K., Henzan K., Hifumi K.

13th ISOPE Pacific/Asia Offshore Mechanics Symposium, PACOMS 2018 315 - 318 2018年01月

担当区分：筆頭著者記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

In order to improve the performance of Darrieus turbine, the pitch angles of the blades are varied and tested in a low-speed wind tunnel. First, the pitch angles of the blades are varied with an interval of 15 degrees, to evaluate the possibility of the improvement. The tested tip-speed ratio is ranged from 0.5 to 2.8, which covers the peak of the power, and the generated torque is measured by a torque meter. However, none of the blades exceed the performance of zero-pitched blade. Then, the pitch angles of the blades are varied but with an interval of 2 degrees. As a result, it is found that the blades with pitch angle of 4 and 6 degrees give the highest torque, especially in a tip-speed ratio over 1. By changing the pitch angle of the blade from 0 to 6 degrees, the peak value of the power coefficients is improved by more than 30 percent.

Scopus

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Development of Dragonfly-Like Flapping Robot 査読有り

Kizu T., Inoue M., Yoshino K., Hiraki K.

Proceedings - 4th International Conference on Applied Computing and Information Technology, 3rd International Conference on Computational Science/Intelligence and Applied Informatics, 1st International Conference on Big Data, Cloud Computing, Data Science and Engineering, ACIT-CSII-BCD 2016 87 - 92 2017年05月

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

In this study, we aimed to develop a dragonfly-like flapping robot with four wings and achieve advanced flight such as hovering and sudden turn. We developed a two-wings-flapping-robot that links the flapping motion moving the wing up and down and feathering motion twisting the wing and perform at the same time. Next, we investigated the performance of the developed robot whether it's possible to control it. In the end, in order to control the vertical of the aircraft we modeled the robot and simulated.

DOI： 10.1109/ACIT-CSII-BCD.2016.028

Scopus

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Flow visualization around a rotating body in a wind tunnel 査読有り

Hiraki K., Zaitsu D., Yanaga Y., Kleine H.

Proceedings of SPIE - The International Society for Optical Engineering 10328 2017年01月

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

© 2017 SPIE. The rotational behavior of capsule-shaped models is investigated in the transonic wind tunnel of JAXA. A special support is developed to allow the model to rotate around the pitch, yaw and roll axes. This 3-DOF free rotational mounting apparatus achieves the least frictional torque from the support and the instruments. Two types of capsule models are prepared, one is drag type (SPH model) and the other is lift type (HTV-R model). The developed mounting apparatus is used in the wind tunnel tests with these capsule models. In a flow of Mach 0.9, the SPH model exhibits oscillations in pitch and yaw, and it rolls half a turn during the test. Similarly, the HTV-R model exhibits pitch and yaw oscillations in a flow of Mach 0.5. Moreover, it rolls multiple times during the test. In order to investigate the flow field around the capsule, the combined technique of color schlieren and surface tufts is applied. This visualization clearly shows the flow reattachment on the back surface of a capsule, which is suspected to induce the rapid rolling motion.

DOI： 10.1117/12.2271143

Scopus

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Relative dynamics and motion control of nanosatellite formation flying 査読有り

Pimnoo A., Hiraki K.

Advances in Space Research 57 ( 7 ) 1476 - 1493 2016年04月

記述言語：英語掲載種別：研究論文（学術雑誌）

Orbit selection is a necessary factor in nanosatellite formation mission design/meanwhile, to keep the formation, it is necessary to consume fuel. Therefore, the best orbit design for nanosatellite formation flying should be one that requires the minimum fuel consumption. The purpose of this paper is to analyse orbit selection with respect to the minimum fuel consumption, to provide a convenient way to estimate the fuel consumption for keeping nanosatellite formation flying and to present a simplified method of formation control. The formation structure is disturbed by J2 gravitational perturbation and other perturbing accelerations such as atmospheric drag. First, Gauss' Variation Equations (GVE) are used to estimate the essential ΔV due to the J2 perturbation and atmospheric drag. The essential ΔV presents information on which orbit is good with respect to the minimum fuel consumption. Then, the linear equations which account for J2 gravitational perturbation of Schweighart-Sedwick are presented and used to estimate the fuel consumption to maintain the formation structure. Finally, the relative dynamics motion is presented as well as a simplified motion control of formation structure by using GVE.

DOI： 10.1016/j.asr.2016.01.004

Scopus

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Relative dynamics and motion control of nanosatellite formation flying 査読有り

Ammarin Pimnoo, Koju Hiraki

Advances In Space Research 57 1476 - 1493 2016年01月

Hovering test of flapping robot using circular flight device 査読有り

Hiraki K., Mie N., Yoshino K., Inoue M.

MOVIC 2014 - 12th International Conference on Motion and Vibration Control 2014年01月

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

© 2014 The Japan Society of Mechanical Engineers. For the purpose of simulating a flight of a flapping vehicle a test device with a circular flight has been developed. The device provides us a flight speed, the trimmed pitch angle and the generated lift force which can be derived from the angle of a vertical arm. Thanks to this device, the appropriate parameters to achieve a stable flight can be set in advance without damaging a vehicle, such as the flapping frequency, the feathering angle and the elevator angle. In the present paper the deriviation of the lift and pitching moment generated by a flapping motion is described.

Scopus

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Multi degree-of-freedom technique for dynamic characteristics of atmospheric entry capsule 査読有り

Hiraki K., Yasuoka K., Kleine H.

31st AIAA Applied Aerodynamics Conference 2013年09月

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

The dynamic characteristics of a model of an atmospheric entry vehicle were investigated in a transonic wind tunnel. The models were allowed to rotate freely in the tunnel and two kinds of the test devices were prepared with different degrees of freedom. The 1-DOF device allowed the model to rotate only around the pitch axis, and the 3-DOF device allowed the model to rotate around the pitch, yaw and roll axes. The dynamic tests were carried out in flows of Mach 0.5 and 0.9. Both the 1-DOF and 3-DOF tests gave the similar results on the damping properties in pitch and yaw axes. The rapid rolling behavior was also recognized in the 3-DOF test which was seemingly related to the energy conversion from the pitch to yaw axis.

Scopus

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Post-flight analysis of Hayabusa; asteroid sample return capsule 査読有り

Inatani Y., Ishii N., Yamada T., Hiraki K., Yamada K., Suzuki T., Fujita K.

Advances in the Astronautical Sciences 146 685 - 696 2013年04月

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

HAYABUSA(MUSES-C); an asteroid explorer returned to the earth after the 7 years of lengthy and troubled voyage, and its capsule reenters into the Earth's atmosphere. It performed a safe reentry flight and recovery. For the design of the capsule, many considerations were made due to its higher entry velocity and higher aerodynamic heating than those of normal reentry from earth orbit. Taking into account the required functions throughout the orbital flight, reentry flight, and descent/recovery phase, the capsule was deigned, tested, manufactured and flight demonstrated finally. The paper presents the concept of the design and qualification approach of the small space capsule of the asteroid sample and return mission. And presented are how the reentry flight was performed and a brief overview of the post flight analysis primarily for these design validation purposes and for the better understanding of the flight results.

Scopus

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Counter-rotating type tidal-stream power unit playing favorable features in various ocean circumstances 査読有り

Usui Y., Takaki K., Kanemoto T., Hiraki K.

ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE) 6 B 2013年01月

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

The authors have invented the unique counter-rotating type tidal-stream power unit, which is composed of the tandem propellers and the double rotational armature type peculiar generator without the traditional stator. In the unit of the downstream type, the front and the rear propellers counter-drive the outer and the inner armatures of the peculiar generator respectively, in keeping the rotational torque counter-balanced between both propellers/armatures. This paper discusses and verifies experimentally the almighty features of the power unit. The axial force acting on the pillar increases naturally with the increase of not only the stream velocity but also the drag of the tandem propellers. Besides, the tandem propellers bring the symmetrical vertical force from side to side though the single propeller brings the force in one direction. The counter-balanced torque makes it possible to moor the power unit with only one cable/wire/rope, and the behavior of the submerged unit was confirmed experimentally. Copyright © 2013 by ASME.

DOI： 10.1115/IMECE2013-66001

Scopus

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Demonstrative power generation by twin-runner darrieus turbine in Kanmon strait 査読有り

Hiraki K., Wakita R., Kanemeoto T., Yagami R., Takao M.

Proceedings of the International Offshore and Polar Engineering Conference 725 - 729 2012年09月

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

In order to make the electrical-power generation feasible under the lower tidal-current condition the twin-runner Darreus water-turbine was developed. The counter rotations of twin runners are expected to increase the power output. In the water-tunnel tests using a subscale model the revolution numbers were increased up to 120 percent of those at the single-runner configuration. The current-accelerating devices were also investigated. Based on the obtained results, the design of the experimental demonstrator was carried out, which can generate 1.4-kW of electric power. The power generation test is slated to start from March 2012 at Kanmon strait. Copyright © 2012 by the International Society of Offshore and Polar Engineers (ISOPE).

Scopus

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Demonstrative Power Generation by Twin-Runner Darrieus Turbine in Kanmon Strait 査読有り

Koju Hiraki, Ryo Wakita, Toshiaki Kanemoto, Ryoich Yagami, Manabu Takao

Conference Proceedings: The Twenty-second (2012) International Offshore and Polar Engineering Conference 2012年06月

Thrust measurement of deployable propeller for powered paraglider in mars atmosphere 査読有り

Hiraki K., Tashima S., Namikawa M.

Proceedings of the 18th Australasian Fluid Mechanics Conference, AFMC 2012 2012年01月

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

A preliminary design of a propeller of the powered paraglider for Mars exploration was conducted. The blade design was made with the computational method developed by Adkins and Liebeck. In order to obtain the necessary thrust of 7.88N, the propeller diameter was computed to 1.0m. Thus, the propeller should be retracted in an entry probe, and it should have self-deploying capability. A one-fourth scaled model of the propeller was fabricated to demonstrate its capability and thrust. The special thrust-measurement device was designed for a wind-tunnel test. Some disagreement was found in the comparison between the measured and predicted thrust. In order to clarify the reason of the discrepancy the aerodynamic data of the wing in low Reynolds number environment were obtained in the wind tunnel. Based on the data obtained the thrust prediction was redone. The agreement was improved and it validated the design process of the blade in this study.

Scopus

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Reynolds-averaged navier-stokes computation of transonic projectiles in ground effect 査読有り

Carriage K., Young J., Kleine H., Hiraki K.

Proceedings of the 18th Australasian Fluid Mechanics Conference, AFMC 2012 2012年01月

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

As a transonic projectile passes near a solid object, its surrounding flow field changes quite considerably: the bow shock naturally adopts a strong solution and pushes forward from its freeflight position, and the projectile's wake is pulled down towards the object. These phenomena were first captured separately by schlieren imaging techniques during live fire and wind tunnel testing. A subsequent computational study, performed in Fluent at a free stream pressure of 72 kPa and for a projectile Mach number of 1.1, demonstrated that the presence of the wall introduces aerodynamic forces whose magnitude and direction can become significant for the subsequent projectile trajectory. The lift force was found to be up to ten percent of the projectile's drag, and may be either positive or negative depending on the proximity to the ground. Similarly, the coefficient of moment may be either positive or negative with a neutral point that does not coincide with the point of zero lift. The results are pertinent to many fields including aircraft weapons release and low level operations, wing-in-ground effect vehicles, and vehicles designed to challenge the land speed record.

Scopus

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Lift-force Measurement for Hovering Flight of Four-Winged Flapping Micro Aerial Vehicle 査読有り

Koju Hiraki, Kazuki Fujii

Proceedings of ASME-JSME-KSME Joint Fluids Engineering Conference 2011 2011年07月

Separated flow around a rotating gyroball 招待有り査読有り

Koju Hiraki, Kota Ishitsu, Keisuke Yamada

Journal of Visualization 14 201 - 211 2011年04月

Particle damping with granular materials for multi degree of freedom system 招待有り査読有り

Masanobu Inoue, Isao Yokomichi, Koju Hiraki

Shock and Vibration 18 ( 1-2 ) 245 - 256 2011年02月

Scientific Application and Design of Small Unmanned Aircraft Systems 査読有り

Andreas Scholtz,Thomas Krueger,Claus-Sebastian Wilkens,Koju Hiraki,Peter Voersmann

AIAC14 Fourteenth Australian International Aerospace Congress 2011年02月

Experimental study on dynamic instability of re-entry capsule-shaped body using pressure sensitive paint 査読有り

Sugimoto D., Nagai H., Asai K., Hiraki K.

48th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition 2010年12月

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

Re-entry capsule with flat body shapes tends to be dynamically unstable in the transonic speed range, and sometimes fall into self-exited pitching oscillation. In this study, the Phase Lock Method with a fast-responding Pressure-Sensitive Paint (PSP) has been employed to visualize unsteady pressure distribution on a capsule model undergoing the pitching motion. In addition, the pressure fluctuation was measured using time-series high-speed camera PSP images. Analysis of the PSP results together with pitch angle measurement has revealed that the phase delay of the base surface pressure acts as dynamically unstable moment in the low pitch angles. © 2010 by the American Institute of Aeronautics and Astronautics, Inc.

Scopus

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Improvement of straight-bladed vertical-axis water turbine for tidal current power generation 査読有り

Hiraki K., Wakita R., Inoue M.

Proceedings of the 9th (2010) ISOPE Pacific/Asia Offshore Mechanics Symposium, PACOMS-2010 169 - 174 2010年12月

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

Considering the tidal-current power generation in a narrow strait, a water turbine of vertical axis is preferred, since the multiple-stage system is applicable in the depth direction. The straight bladed vertical axis water turbine (S-VAWT) is appropriate in such system because of its simplicity in manufacture. On purpose to improve the performance of the S-VAWT a Gurney flap was attached on the trailing edge of the rotor blades. The modified turbine was tested in both the wind and water tunnels. Consequently, the attachment of the Gurney flap on the lower surface is effective to enhance the dynamic characteristics of the S-VAWT. Copyright © 2010 by The International Society of Offshore and Polar Engineers.

Scopus

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Improvement of Straight-bladed Vertical-axis Water Turbine for Tidal Current Power Generation 査読有り

Koju Hiraki,Ryo Wakita,Masanobu Inoue

The Ninth (2010) ISOPE Pacific/Asia Offshore Mechanics Symposium PACOMS-2010 2010年11月

トンボに着想を得た4枚翼型羽ばたき機の省エネルギ飛行について査読有り

平木講儒,藤井和希,緒方尚樹

可視化情報学会誌 30 ( 119 ) 16 - 21 2010年10月

Projectiles in Transonic Ground Effect 査読有り

Harald Kleine,Koju Hiraki,Benjamin Oakes,John Young,Hideaki Kusano,Yoshifumi Inatani

The 29th International Congress on High-Speed Imaging and Photonics 2010年09月

Self-Excited Oscillation of Blunt Bodies in Transonic Flow 査読有り

Koju Hiraki,　Harald Kleine,Kenji Mishima,Hirotaka Maruyama,Kazuya Kitamura,Tetsuya Hayashida,Jun Yonai,Hideaki Kusano

The 29th International Congress on High-Speed Imaging and Photonics 2010年09月

Separated Flow around a rotating Gyroball 査読有り

Koju Hiraki,Kota Ishitsu,Keisuke Yamada

14th International Symposium on Flow Visualization 2010年06月

The efficient-flight of four-wing ornithopter 査読有り

Hiraki K., Fujii K., Naoki O.

Proceedings of 2010 Asia-Pacific International Symposium on Aerospace Technology, APISAT 2010 95 - 98 2010年01月

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

Inspired by a dragonfly, which sometimes appears to quit wing-beating, a possibility of a flight with either fore-wing or hind-wing beating of our four-winged flapping vehicle was pursued, in order to achieve the more efficient flight. The wind-tunnel tests were carried out to determine which wing was appropriate to quit, by measuring the lift force on the fixed wing, which was placed in front of or behind the flapping wing. It revealed that the generated lift on the fixed fore-wing showed the dependency inversely to the flapping of the hind-wing. It indicated that the fore-wing is better to fix.

Scopus

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Preliminary study and experiments on water landing of the Japanese ISS cargo return vehicle using a ram-air parachute 査読有り

Ito M., Hiraki K.

Proceedings of 2010 Asia-Pacific International Symposium on Aerospace Technology, APISAT 2010 636 - 639 2010年01月

記述言語：英語掲載種別：研究論文（国際会議プロシーディングス）

This paper reports the status of a preliminary study and experiments on a water landing of the Japanese ISS cargo return vehicle using a ram-air parachute. Our final target of the study is to use a ram-air parachute for the future human space transportation system as an autonomous precision gliding and soft land landing technology to predetermined conventional landing sites, such as those in the Japanese islands. The purpose of applying the ram-air parachute to the ISS cargo return vehicle is to demonstrate the feasibility and practicability of a ram-air parachute for a reentry vehicle from space. We also demonstrate the water landing capability as a contingency landing scenario of the future human space transportation system. To compare the characteristics of a gliding water landing by a ram-air parachute with a non-gliding vertical landing, some cases of water landing tests using a miniature model of a ram-air parachute and a capsule were conducted. Using the results of the tests, we confirmed the effects of impact attenuation by gliding landings. In addition, we found that an optimization of a water landing approach using flare control is important to minimize the impact loads during water landings.

Scopus

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Particle Damping with Granular Materials for Multi Degree of Freedom System 査読有り

Masanobu Inoue,Isao Yokomichi,Koju Hiraki,Takeharu Tsuruta

2nd International Conference on Vibro-Impact Systems 2010年01月

小型パラフォイルを利用した自律飛行システム査読有り

平木講儒,井上昌信

日本航空宇宙学会誌 57 ( 671 ) 341 - 346 2009年12月

Development of Autonomous Flight Systems with Small Parafoil 査読有り

Koju Hiraki,Masanobu Inoue

20th AIAA Aerodynamic Deceleratory Systems Technology Conference 2009年05月

Flow Instability Induced by Spiked Bodies 査読有り

Koju Hiraki,Harald Kleine,Hirotaka Maruyama,Tetsuya Hayashida,Kazuya Kitamura,Jun Yonai,Takashi Nakajima,Goji Etoh

Proceedings of SPIE: 28th International Congress on High-Speed Imaging and Photonics 7126 71260K.1 - 71260K.8 2009年02月

Reentry Motion and Aerodynamics of the MUSES-C Sample Return Capsule 査読有り

Nobuaki Ishii,Tetsuya Yamada,Koju Hiraki,Yoshifumi Inatani

Transactions of the Japan Society for Aeronautical and Space Sciences 51 ( 172 ) 65 - 70 2008年08月

気球を利用した無重力実験のための機体開発とそのフライト結果査読有り

澤井秀次郎,橋本樹明,坂井真一郎,坂東信尚,小林弘明,藤田和央,吉光徹雄,石川毅彦,稲富裕光,福家英之,鎌田幸男,星野慎二,田島賢一,門岡昇平,上原聡,小島孝之,上野誠也,宮路幸二,坪井伸幸,平木講儒,鈴木宏二郎,松島清穂,中田孝

日本航空宇宙学会論文集 56 ( 654 ) 339 - 346 2008年07月

Cavitation induced by low-speed underwater impact 査読有り

H. Kleine,S. Tepper,K. Takehara,T.G. Etoh,K. Hiraki

International Symposium on Shock Waves 2007年07月

Balloon-Drop Test for Evaluation of Guiding Performance of Small-Parafoil Flight System 査読有り

Koju Hiraki,Koichiro Kawazoe,Takayuki Imoto,Masanobu Inoue

19th AIAA Aerodynamic Decelerator Systems Technology Conference 2007年05月

Visual Determination of the Onset of Irregular Blast Wave Reflection 査読有り

H Kleine,K Hiraki,E Timofeev，K Ohashi,H Maruyama，T Hayashida,J Yonai,K Kitamura,T Nakajima,A Gojani,K Takayama,T Etoh

27th International Congress on High Speed Photography and Photonics 2006年09月

Visualization of the Unsteady Flow Field around Spiked Concave Bodies in Supersonic Flow 査読有り

Koju Hiraki,Harald Kliene,Hirotaka Maruyama,Tetsuya Hayashida,Kazuya Kitamura,Jun Yonai,Takashi Nakajima,Takeharu Etoh

12th International Symposium on Flow Visualization 2006年09月

An Experimental Study of Micro Air Vehicle with Flapping and Feathering Wings by a Single Motor 査読有り

Koju Hiraki,Naofumi Goto,Tsunanori Okubo,Koichiro Kawazoe,Keisuke Yamada,Yasuaki Nishii,Kazuoki Harada,Masanobu Inoue

The 3rd International Symposium on Aero Aqua Bio-Mechanisms 2006年07月

Transonic Dynamic Instability of Blunt-nosed Recovery Vehicle Validated by Actual Reentry Flight 査読有り

K. Hiraki,S. Matsuda,K. Ijichi,T. Abe

56th International Astronautical Congress 2005年10月

Measurements on Slight Rolling Torque Acting on A Slender Body 査読有り

平木　講儒

21st International Congress on Instrumentation in Aerospace Simulation Facilities 2005年09月

Lateral-Directional Characteristics of Parafoil Obtained from Sled and Free-Flight Experiments 査読有り

K Hiraki,Y Mizuta,Y Saito,M Inoue

18th AIAA Aerodynamic Decelerators Systems Technology Conference 2005年05月

High-speed time-resolved color schlieren visualization of shock wave phenomena 査読有り

H Kleine,K Hiraki,H Maruyama,T Hayashida,J Yonai,K Kitamura,Y Kondo,TG Etoh

Shock Waves 14 ( 5-6 ) 333 - 341 2005年04月

サンプルリターンカプセルの研究と開発査読有り

稲谷芳文,石井信明,山田哲哉,平木講儒

日本航空宇宙学会誌 53 ( 619 ) .248 - 255 2005年04月

小惑星サンプルリターンカプセルの空気力学査読有り

稲谷芳文,石井信明,山田哲哉,平木講儒

ながれ ( 24 ) 297 - 305 2005年04月

Attitude Stability of Blunt-Body Capsules in Hypersonic Rarefied Regime 査読有り

Kazuhisa Fujita,Yoshifumi Inatani,Koju Hiraki

Journal of Spacecraft and Rockets 41 ( 6 ) 925 - 931 2004年11月

Supersonic Flow over Double Cone Geometries 査読有り

Harald Kleine,Koju Hiraki

24th International Symposium on Shock Waves 2004年07月

Dynamic Behavior of the Shock Wave Formed around a Reflector in Supersonic Flow 査読有り

Koju Hiraki,Harald Kleine

24th International Symposium on Shock Waves 2004年07月

Preliminary Study on a MAV with Flapping Wing 査読有り

Tunanori Ohkubo,Yuji Fukunaga,Msanobu Inoue,Koju Hiraki

24th International Symposium on Space Technology and Science 2004年06月

Experimental Study on Dynamic Behavior of Spin-Type Solar-Sail 査読有り

Tomohiro Fujie,Yoshiyuki Mizuta,Koju Hiraki,Masanobu Inoue

24th International Symposium on Space Technology and Science 2004年06月

Experimental Approach to identify the Longitudinal and Lateral Stability of Flexible Parafoil 査読有り

平木　講儒

AIAA 2003-2145 2003年04月

Transonic Dynamic Instability of Disk-shaped Capsule

未入力

The Institute of Space and Astronautical Science Report SP No.17 2003年04月

The Aerodynamic Data Base for Asteroid Sample Return Capsule

未入力

The Institute of Space and Astronautical Science Report SP No.17 2003年04月

Aerodynamic Stability of Parafoil 査読有り

未入力

Proceedings of the 23rd International Symposium on Space Technology and Science 2002年04月

Numerical Analysis of Dynamic Stability of a Reentry Capsule at Transonic Speeds(Jointly Authored) 査読有り

平木　講儒

AIAA Journal 39 ( 4 ) 646 - 653 2001年04月

The Experimental Study of Correlation between Base Pressure and Attitude Motion of Reentry Capsule 査読有り

平木　講儒

Proceedings of the Twenty-second International Symposium on Space Technology and Science 894 - 899 2000年04月

Experimental Study on Dynamic Instability of Capsule-shaped Body

平木　講儒

ISAS Report ( No.103 ) 1999年04月

カプセル型物体の動的不安定性についての実験的研究

平木　講儒

宇宙科学研究所報告 ( 第103 ) 1999年04月

Dynamic Stability of MUSES-C Capsule 査読有り

平木　講儒

Proceedings of the Twenty-first International Symposium on Space Technology and Science 945 - 950 1998年04月

Flow Measurement around Rigid Parachute-like Bodies in Supersonic Free Stream(Jointly Authored) 査読有り

平木　講儒

AIAA CP976 429 - 438 1997年04月

An Arc-Heated High Enthalpy Test Facility for Thermal Protection Studies(Jointly Authored)

平木　講儒

The Institute of Space and Astronautical Science Report ( 664 ) 1996年04月

再突入環境模擬装置と気流計測技術（）査読有り

未入力

日本航空宇宙学会誌第４３巻 ( 第４９９号 ) 1995年04月

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