著者
小林 啓二
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会誌 (ISSN:00214663)
巻号頁・発行日
vol.64, no.10, pp.305-308, 2016

<p>日本では,総務省消防庁,災害派遣医療チーム(DMAT),自衛隊等の災害対応機関が運用する災害救援航空機による救援活動が頻繁に発生している.宇宙航空研究開発機構(JAXA)が研究開発を進めてきた「災害救援航空機情報共有ネットワーク(D-NET)」の目的は,①「より安全かつ効率的な救援航空機の運用を実現するために災害対応機関間での情報共有を実現する」,②「共有された情報に基づいて機種や装備等に応じた最適な任務割当支援を行う」ことである.JAXAは,機上及び地上システムの開発を行い,災害対応機関と連携して実運用下での有効性評価を実施してきた.その結果,D-NETを活用することにより,無駄時間(任務割当待ち時間,離着陸許可までの時間,給油待ち時間等)や異常接近確率を従来方式と比較して50%以上削減可能であることを確認した.研究開発されたD-NET技術のうち,特に有効性が認められたものについては民間企業等に技術移転され,実運用で使用されてきている.現在は,ヘリコプタのみではなく,陸域観測技術衛星(ALOS-2)や無人機などで観測された災害情報も共有化し,ヘリコプタによる救援活動の計画立案に役立てるシステムの研究開発(D-NET2)を進めている.</p>
著者
故山名 正夫 伊藤 光
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会誌 (ISSN:00214663)
巻号頁・発行日
vol.25, no.279, pp.201-207, 1977-04-05 (Released:2009-05-25)
参考文献数
5

Experimental studies for determining the profiles of the wing sections with high maximum lift coefficient is described. Observation of flow around the wing sections and measurement of section lift coefficient are carried out in a twodimensional smoke wind-tunnel. Transition in the boundary layer along the wing surfaces is also observed by using evaporated-gas-oil smoke. Additionally, the wing sections with extended trailing-edge are investigated. Maximum lift coefficient up to 2.28 is obtained at Reynolds number of 5.34×105.
著者
橋本 毅 木村 春夫
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会誌 (ISSN:00214663)
巻号頁・発行日
vol.36, no.412, pp.249-254, 1988-05-05 (Released:2010-12-16)
参考文献数
17

Equations for evaluating the performances of a failure detection system, whose task is to detect changes of some parameters in an object system, are derived as functions of the design parameters in the detection system and a design method of the detection system based on the equations is proposed. This detection system consists of the Kalman filters and the Modified Sequential Probability Ratio Test. The usefulness of this design method is examined by means of numerical simulations for the parameter changes in a second order system and for the failure in an aircraft stability augumentation system.
著者
中山 勝之 坂村 芳孝
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会論文集 (ISSN:13446460)
巻号頁・発行日
vol.56, no.655, pp.363-369, 2008 (Released:2008-08-27)
参考文献数
22

The present paper reports the result of a numerical study on efficient solution-adaptive grid refinement algorithms for simulating unsteady flows with discontinuities. We implement a flow feature detection algorithm originally developed for quadrilateral grids by Aftosmis and Kroll (AIAA Paper 91-0124, 1991) to achieve efficient adaptation for triangular grids for simulating strongly unsteady flows with moving discontinuities such as shock waves and contact discontinuities. In their algorithm, the detection of strong shock waves is isolated from that of other smooth flow features, and the threshold for grid refinement is automatically tuned based on the statistics of grids in the smooth flow feature detection step. We illustrate the performance of the algorithm with numerical results for two benchmark problems (shock tube and double Mach reflection problems) of two-dimensional unsteady flows.
著者
SUGIMURA Nobuo HASHIMOTO Tatsuaki KUWAHARA Toshinori SAKAMOTO Yuji YOSHIDA Kazuya SATO Yuki TAKANO Tomohiro
出版者
一般社団法人 日本航空宇宙学会
雑誌
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN
巻号頁・発行日
vol.14, no.30, pp.Pf_97-Pf_103, 2016
被引用文献数
1

<p>A new star sensor for a microsatellite was developed for accurate and reliable attitude detection. Microsatellite RISING-2, which was launched on May 24, 2014, has raised some issues with regard to the functionality of its star sensor. It is confirmed that white spots caused by space radiation and the stray light of sunshine induce a false detection of the satellite's attitude, which imposes significant limitations on satellite operations. To make improvements, the brightness value of the picture was studied. This paper proposes avoidance algorithms for white spots and stray light. The effects of these algorithms were validated to process the flight data from RISING-2 in a software simulation. The soundness of the star sensor is indicated via attitude detection tests against several star patterns using real flight images taken by RISING-2. Thereafter, avoidance algorithms were integrated in a newly developed processing board. In this board, the avoidance algorithm for white spots was composed using both a hardware logic filter and a software filter. The avoidance algorithm for stray light was expressed using only a software filter. During the programming of these algorithms, the functionality of the satellite's attitude detection was verified in a generic test environment. This system displays the entire sky view of stars on a monitor and enables attitude detection tests for all star images regardless of time or location. As a result, the satellite's attitude was detected normally by this board. Finally, the effectiveness of the software filter for the avoidance algorithm for white spots was confirmed by using sample photographs, including those with white spots.</p>
著者
秋山 皓平 手塚 亜聖 砂田 保人 李家 賢一
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会論文集 (ISSN:13446460)
巻号頁・発行日
vol.57, no.671, pp.476-485, 2009 (Released:2009-12-14)
参考文献数
15
被引用文献数
1

This paper investigates wing aerodynamic characteristics used for bi-plane micro-air vehicles. Surface pressure distributions of two-dimensional biplane airfoils (4% cambered-plate airfoil) were measured at a chord Reynolds number of 6.4 × 104. Lift characteristics of three-dimensional biplane rectangular wings (aspect ratio of 3) were also measured at the same Reynolds number. It was indicated that the behaviors of laminar separation bubble formed both on the upper and lower airfoils/wings affects their lift characteristics. Bi-plane wings with positive stagger, i.e. protruded upper wing indicated higher maximum lift coefficient. This is caused by different behaviors of laminar separation bubble formed on the wing.
著者
近藤 夏樹 辻内 智郁 村重 敦 西村 宏貴 青木 誠 土橋 明彦 山川 榮一 青山 剛史 齊藤 茂
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会論文集 (ISSN:13446460)
巻号頁・発行日
vol.51, no.592, pp.198-206, 2003 (Released:2003-09-26)
参考文献数
16

A low-noise helicopter blade, AT1, was designed with the concept of reducing noise without the drop of rotor performance. In the concept, High-Speed Impulsive (HSI) noise is reduced by applying a thin airfoil in the tip region and a dog-tooth like extension in the leading-edge of the tip region. Blade-Vortex Interaction (BVI) noise is reduced by applying the extension and a strong taper near the tip end. The stall angle of the blade is increased by the effect of the vortex generated from the leading-edge extension. As a result, the drop of rotor performance caused by the thin airfoil and the reduction of rotor rotational speed is recovered. The low-noise characteristics and the performance of AT1 were evaluated by a model rotor test conducted at Deutsch Niederländischer Windkanal (DNW). It is shown that AT1 reduces HSI noise and BVI noise and has good performance in forward flight conditions. However, the improvement of performance in high-lift conditions still remains as a future problem.
著者
大依 仁
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会誌 (ISSN:00214663)
巻号頁・発行日
vol.63, no.2, pp.38-40, 2015-02-05 (Released:2017-06-12)

航空エンジン電動化システム(MEE:More Electric Engine)は次世代の航空機用エンジンへの適用をめざした制御コンセプトである.MEEには,航空機における電動化と連携した2つの役割があり,エンジンの燃費改善,整備性向上,より高い信頼性・安全性を目指すPropulsionとしてのMEEと電動化の大きな電力需要を担う,Power PlantとしてのMEEである.今回はこれらの役割を担うMEE研究の現状について紹介する。エンジンシステムの電動化によりシステムの無駄を省き,燃費や熱のマネジメントなどを改善する研究,電力需要の増加による発電抽出力とエンジン制御の最適化を目指す研究,統合化推進制御として,システム最適化に向けた,燃料,電力,制御システムと推進システムの統合化の調査研究である.まとめに,MEE実用化に向けた課題として,機体メーカの視点とエアラインの視点を紹介する.
著者
國中 均 西山 和孝 清水 幸夫 都木 恭一郎 川口 淳一郎 上杉 邦憲
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会論文集 = Journal of the Japan Society for Aeronautical and Space Sciences (ISSN:13446460)
巻号頁・発行日
vol.52, no.602, pp.129-134, 2004-03-05
被引用文献数
4 6

The microwave discharge ion engine generates plasmas of the main ion source as well as the neutralizer using 4GHz microwave without discharge electrodes and hollow cathodes, so that long life and durability against oxygen and air are expected. MUSES-C "HAYABUSA" spacecraft installing four microwave discharge ion engines was launched into deep space by M-V rocket on May 9, 2003. After vacuum exposure and several runs of baking for reduction of residual gas the ion engine system established the continuous acceleration of the spacecraft toward an asteroid. The Doppler shift measurement of the communication microwave revealed the performance of ion engines, which is 8mN thrust force for a single unit with 3,200sec specific impulse at 23mN/kW thrust power ratio. At the beginning of December 2003 the accumulated operational time exceeded 7,000 hours and units.
著者
渡辺 一尊 鈴木 悠人 原田 裕子 齋藤 雅樹 上野 真史 森本 仁 上田 敦史
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空宇宙学会誌 (ISSN:00214663)
巻号頁・発行日
vol.66, no.5, pp.141-147, 2018-05-05 (Released:2018-05-05)
参考文献数
4

きぼうロボットアームは,親アーム,子アームから構成され,現在は曝露ペイロードの移設などすべてのアーム運用を地上からの遠隔操作で行っている.2015年5月のExHAM 1号機による初回ミッションでは,ExHAMをきぼうエアロックから船外へ搬出し,JEM曝露部上の電気箱Survival Power distribution Box(SPB)のハンドレールに,子アーム特有の力覚制御を使用した押し付け動作により取り付けた.この半年後の2015年11月には,ExHAM 2号機を同様のシーケンスで船外搬出し,JEM曝露部上Exposed Facility System Controller a(ESC a)のハンドレールへの初の取り付けに成功している.本稿では,Ex-HAM 1, 2号機のJEM曝露部への設置,船内回収を定期的に行ってきたきぼうロボットアームの運用実績について述べる.
著者
井町 勇
出版者
一般社団法人 日本航空宇宙学会
雑誌
日本航空學會誌
巻号頁・発行日
vol.7, no.62, pp.518-524, 1940

To check the adaptability of the assumption that the slip is proportional to the shearing load of that rivet, complete load-deformation graphs were plotted. The law of proportionality practically holds up to about 1/3 of the ultimate strength. Sunk rivets are ellastically stronger than ordinary rivets, e ?? pecially for thinner plates. The values of k for steel plates with steel rivets are about 1/3 of those for duralumin and well coincide with the relation of their proper elastic constants of materials.<BR>Spot-welded joints were also tested both for duralumin and stainless steel; the comparison of k's relating to their welded areas shows that the rigidity is of the same order as that of rivetted joints. Further, tests were extended to the combinations steel plates with duralumin rivets and duralumin plates with steel rivets, and the results show that k depends considerably on the material of rivet itself.