著者
Masahiko YAMAZAKI Yasuyuki MIYAZAKI
出版者
(一社)日本航空宇宙学会
雑誌
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN (ISSN:18840485)
巻号頁・発行日
vol.8, no.ists27, pp.Pc_35-Pc_40, 2010 (Released:2010-12-29)
参考文献数
1
被引用文献数
1

The Spinning solar sail is expected to be a future space exploration system. Considering the dynamic deformation of the sail membrane is an indispensable factor in designing the spacecraft. But the mathematical model of the sail membrane is complex. Computational analysis is difficult and time consuming. Therefore this has a negative impact on simulation, design and control problems. The model reduction technique is required to shorten the design period. It is a necessary step in order to put the gossamer structure to practical use. In this presentation, the dynamic property of the square type spinning solar sail is revealed, and the requirements for constructing a reduction model are revealed. Then, empirical model reduction techniques are applied to gossamer structures, and the issue of constructing a low-order model is summarized.
著者
Muneo TAKAOKI Sachiko YANO Naomi MATHERS Fenny DWIVANY Rizkita ESYANTI Thomas DJAMALUDDIN Mhd Fairos ASILLAM Farahana KAMARUDIN Mohammed Selamat MADOM Sawat TANTIPHANWADI Nguyen Vu GIANG Kibo-ABC
出版者
(一社)日本航空宇宙学会
雑誌
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN (ISSN:18840485)
巻号頁・発行日
vol.12, no.ists29, pp.Tp_1-Tp_5, 2014 (Released:2014-10-01)
被引用文献数
1

The “Space Seeds for Asian Future (SSAF)” program is one of the activities of the “Kibo-ABC” initiative under the Asia-Pacific Regional Space Agency Forum (APRSAF). The program intends to promote understanding, and to give regional space agencies experience in the utilization of the Japanese Experiment Module, “Kibo”, of the International Space Station (ISS). It also aims to provide young people in the Asia-Pacific region with opportunities to learn about leading edge sciences through their participations in experiments under peculiar space conditions, including microgravity. Students from Indonesia, Malaysia, Thailand and Vietnam participated in the SSAF2010-2011 program. As part of this program seeds from each of these nations were flown to the ISS and kept in the Kibo Module. These seeds were then returned to Earth where they were germinated and compared to control seed not flown in space. This experiment involved researchers, students and the general public. In the SSAF2013 program, there are plans to cultivate seeds indigenous to Asia in the Kibo/ISS facilities. The plan is to send Azuki bean (Vigna angularis) to Kibo, and observe the growth of their seedlings under dark conditions. Members of the Kibo-ABC initiative are collaborating in the preparation of the seed germination testing procedures, following which many people, including children, students and researchers, are expected to participate in the program.
著者
Kojiro SUZUKI
出版者
THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
雑誌
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN (ISSN:18840485)
巻号頁・発行日
vol.16, no.5, pp.412-419, 2018 (Released:2018-07-04)
参考文献数
15
被引用文献数
1 1

A Mars orbiter/lander mission using a micro-satellite (less than 100 kg at Mars arrival) with a deployable membrane aeroshell for the orbit insertion by the aerocapture and the electric propulsion for the trajectory maneuver was considered. The aerodynamic heating environment during the atmospheric flight was investigated solving the thermo-chemical nonequilibrium axi-symmetric Navier-Stokes equations around the spacecraft with the flare-shaped aeroshell. To obtain the appropriate amount of deceleration at the atmospheric pass, the drag modulation technique, in which the aeroshell is timely jettisoned from the spacecraft, was assumed. The hypersonic wind tunnel experiment successfully demonstrated that the backward jettison works well without significant time delay and attitude disturbance. Finally the corridor width for the entry path angle was estimated considering the ability of the orbit insertion, the peak aerodynamic heating, and the capability of the electric propulsion to raise the periapsis altitude. The combination of a low ballistic coefficient flight with the membrane aeroshell and an electric propulsion works well to acquire a finite width of the entry corridor for the aerocapture.
著者
Hironori SAHARA Satoshi HOSODA Yoshiki SUGAWARA Masakatsu NAKANO Shinichi NAKASUKA
出版者
THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
雑誌
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN (ISSN:18840485)
巻号頁・発行日
vol.8, no.ists27, pp.Tu_1-Tu_4, 2010 (Released:2011-06-14)
参考文献数
1

This paper proposes to hold “Ig Satellite Design Contest,” in order to expand our space utilization by means of content-based satellites in the stream of recent microsatellite development. Going back to the history of the recent microsatellite, such a content-based satellite is positioned as the third-generation one. Ig Satellite Design Contest stands on the position of the two policies, that is, the satellite is chip in porridge for practical effect, but is to bring pleasure or happiness to people, or to stimulate access to the space and our future space activities.
著者
Hironori SAHARA Satoshi HOSODA Yoshiki SUGAWARA Masakatsu NAKANO Shinichi NAKASUKA
出版者
THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
雑誌
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN (ISSN:18840485)
巻号頁・発行日
vol.10, no.ists28, pp.Tf_1-Tf_4, 2012 (Released:2012-03-29)
参考文献数
1

We organize Ig Satellite Design Contest to collect the NEEDS and to establishment of NEEDS database for microsatellite. It will be polestar for the satellite developers. This paper shows an example of NEEDS collection and derivation of the key technologies from the NEEDS, which should offer a strategic direction to the SEEDS, the satellite developers for example.
著者
Naoyuki NISHIO Shin-Ichiro NISHIDA Shintaro NAKATANI
出版者
THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
雑誌
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN (ISSN:18840485)
巻号頁・発行日
vol.19, no.4, pp.469-476, 2021 (Released:2021-07-04)
参考文献数
16
被引用文献数
1

The rover for future Mars exploration will be expected to have higher rough terrain traveling performance compared with conventional rovers. In this paper, we propose a rover with a weight of about 30 kg that can be transported to Mars by a Japanese rocket. The purpose of this study is to propose and develop a hinge-type movable center-of-gravity mechanism wherein the bending of the rover's body with a motor shows high rough terrain-driving performance with minimum degrees of freedom. The proposed mechanism's performance is evaluated by conducting travel experiments on a assumed terrain, that is, a hard rock with a grade inclination of 45 deg and a height of 0.15 m above the sand. The effectiveness of the proposed mechanism in getting over a step was confirmed by conducting experiments using a prototype model.
著者
Yohsuke NAMBU Masashi MIURA Ryosuke YOSHIZAWA Toshishige HAGIHARA Shunsuke KIMURA Akira YUMIYAMA Satoru IGARASHI
出版者
THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
雑誌
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN (ISSN:18840485)
巻号頁・発行日
vol.14, no.ists30, pp.Pt_15-Pt_24, 2016 (Released:2016-11-26)

This research aims to develop a web application to realize open model-based collaboration (Open MBC), which is a framework to support efficient and collaborative development of complex systems. We describe the concept of Open MBC and the features of the web application. Furthermore, we introduce an actual case, presenting requirements analysis and management to use the application in the CubeSat project at Osaka Prefecture University. Feedback from students described the difficulty of systems engineering and functional weaknesses prevented the use of our application. Based on this feedback, the paper proposes improvements to functions and operation methods.
著者
Mitsugu OHKAWA Hiromitsu WAKANA Amane MIURA
出版者
THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
雑誌
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN (ISSN:18840485)
巻号頁・発行日
vol.17, no.2, pp.142-149, 2019 (Released:2019-03-04)
参考文献数
8

This paper proposes and investigates the use of Adaptive Coding and Modulation (ACM) to maintain high frequency utilization efficiency in accordance with the change of power limits and frequency bandwidth channel limits for the Ka-band high through-put satellite (HTS) system. Improvements in frequency utilization efficiency of the Ka-band satellite channel model have been observed when carrying out ACM using the DVB-S2X modulation scheme and error correcting codes.
著者
Yuichi OI Yasuhito HIRAI Shotaro DOKI Yuh OHTAKI Daisuke HORI Christina-Sylvia ANDREA Shin-ichiro SASAHARA Tamaki SAITO Ichiyo MATSUZAKI
出版者
THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
雑誌
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN (ISSN:18840485)
巻号頁・発行日
vol.16, no.6, pp.476-480, 2018 (Released:2018-09-04)
参考文献数
16

NIRS measurement was carried out in a confinement experiment for the first time. A tendency for NIRS integrated values to decrease was observed. Problems such as the learning effect needed to be resolved. SOC had an upward trend. Regarding POMS, the first day of confinement showed the highest score, after which no obvious deterioration was seen.
著者
Kazuya YAGINUMA Jun ASAKAWA Yuichi NAKAGAWA Yoshihiro TSURUDA Hiroyuki KOIZUMI Kota KAKIHARA Kanta YANAGIDA Yusuke MURATA Mikihiro IKURA Shuhei MATSUSHITA Yoshihide AOYANAGI Takeshi MATSUMOTO
出版者
THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
雑誌
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN (ISSN:18840485)
巻号頁・発行日
vol.18, no.4, pp.141-148, 2020 (Released:2020-07-04)
参考文献数
27
被引用文献数
1 2

The AQua Thruster-Demonstrator (AQT-D) is a 3U CubeSat for demonstrating the water resistojet propulsion system developed by the University of Tokyo. The AQT-D was launched to rendezvous with the International Space Station (ISS) in the middle of 2019. This spacecraft will also be the world’s first ISS-deployed CubeSat equipped with a water propulsion system. AQT-D is comprised of a 1U propulsion system and 2U bus systems. The bus systems of the AQT-D were designed and developed based on the TRICOM-1R, also known as "Tasuki," was launched using a SS-520 nanosatellite launcher and was in operation during 2017-2018. The AQUA ResIstojet propUlsion System (AQUARIUS-1U) has one Delta-V-Thruster (F: 4 mN) for orbital maneuver and four Reaction-Control-Thruster (F: 1 mN) for reaction control. AQUARIUS-1U is a resistojet propulsion system comprised of a tank, a vaporization chamber and nozzles. It uses water as a propellant (i.e., propellant mass was less than 400 g. Ultimate green propellant: water (H2O) enables ISS-deployed CubeSat to install a propulsion system. It is expected that use of the CubeSat deployed by the ISS will expand drastically as the propulsion system lengthens the satellite lifetime, which is one of the bottlenecks for the low-earth-orbit CubeSat. This paper discusses the mission overview of the AQT-D and the ground test results of the propulsion system installed in it.
著者
Naoki IZUTSU Daisuke AKITA Hideyuki FUKE Issei IIJIMA Yoichi KATO Jiro KAWADA Kiyoho MATSUSHIMA Yukihiko MATSUZAKA Eiichi MIZUTA Takashi NAKADA Naoki NONAKA Yoshitaka SAITO Atsushi TAKADA Keisuke TAMURA Kazuhiko YAMADA Tetsuya YOSHIDA
出版者
THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
雑誌
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN (ISSN:18840485)
巻号頁・発行日
vol.8, no.ists27, pp.Pm_7-Pm_13, 2010 (Released:2010-12-29)
参考文献数
1
被引用文献数
1 1

A zero-pressure balloon used for scientific observation in the stratosphere has an unmanageable limitation that its floating altitude decreases during a nighttime because of temperature drop of the lifting gas. Since a super-pressure balloon may not change its volume, the lifetime can extend very long. We had introduced so called the ‘lobed-pumpkin’ type of super-pressure balloon that can realize a full-scale long-duration balloon and it will be in practical use in the very near future. As for larger super-pressure balloons, however, we still have some potential difficulties to be resolved. We here propose a new design suitable for a larger super-pressure balloon, which is roughly ‘lobed pumpkin with lobed cylinder’ and can adapt a single design for balloons of a wide range of volumes. Indoor inflation tests were successfully carried out with balloons designed and made by the method. It has been shown that the limit of the resisting pressure differential for a new designed balloon is same as that of a normal lobed-pumpkin balloon.
著者
Tomomasa SHIBUYA Toshinori KUWAHARA Pasith TANGDHANAKANOND Shinya FUJITA Yuji SATO Kosuke HANYU Yu MURATA Adrien POTIER Morokot SAKAL Yuji SAKAMOTO
出版者
THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
雑誌
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN (ISSN:18840485)
巻号頁・発行日
vol.19, no.6, pp.855-864, 2021 (Released:2021-11-04)
参考文献数
20

The Space Robotics Laboratory (SRL) of Tohoku University has developed a 50-kg-class microsatellite called RISESAT, which was launched in January 2019. The main missions of this satellite are to conduct earth observation using a high-resolution telescope and perform a demonstration of optical communication. To achieve these missions, it is necessary to maintain the on-board components in a specified safe temperature range. In this satellite, on-board components such as the battery and power control unit are mounted to the central pillars of the satellite structure, which are insulated from the outer panels, and are thus not easily affected by the external environment. Therefore, it is important to determine the amount of heat generation by the components as well as the heat transfer parameters between structure panels. The purpose of this study is to determine the parameters such as thermal contact conductance between structure panels and heat generation of the components. We conducted the thermal vacuum tests to improve the accuracy of the determination of these parameters. Finally, we analyzed the flight data and evaluated the validity of the parameter determination using data from the regular operations phase of the mission. The seasonal effects on the thermal design were also evaluated using data from the first 480 days after launch.
著者
Yusuke OZAWA Shota TAKAHASHI Javier HERNANDO-AYUSO Stefano CAMPAGNOLA Toshinori IKENAGA Tomohiro YAMAGUCHI Bruno V. SARLI
出版者
THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
雑誌
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN (ISSN:18840485)
巻号頁・発行日
vol.17, no.4, pp.496-505, 2019 (Released:2019-07-04)
参考文献数
12
被引用文献数
1

OMOTENASHI is a 6U CubeSat that will be launched in 2019 by the Space Launch System (SLS) with the objective of landing on the Moon. The CubeSat is planned to perform two deterministic maneuvers. The first maneuver (DV1) by gas jet propulsion system transfers the probe from the nominal SLS trajectory to a lunar targeted trajectory. The second maneuver (DV2) is applied by the solid rocket motor before landing to counteract the vertical component of the S/C velocity. The high approach speed at the Moon, combined with large errors induced by the solid motor, requires the probe to approach the Moon with a shallow Flight Path Angle (FPA). If the angle is too steep, expected errors in the DV2 may cause the probe to crash. However, a shallow FPA increases the probability of a Moon-flyby or collision with the local topography. In this paper, we present a design method for Earth-Moon transfer trajectory robust to orbit determination (OD) and DV1 execution errors. First step consists of a grid search to determine the nominal DV1 vector with four candidates obtained. Subsequent error analysis suggests the need for a Trajectory Correction Maneuver (TCM). For the two scenarios of OD error provided by the navigation team, an error analysis was conducted including the TCM. Two realistic OD error scenarios were considered: 30 min or 3 hours of two-way Doppler and range measurement. Error analysis conducted considering TCM shows the need for 3 hours of OD to achieve nearly 100% of transfer success rate.
著者
Yuichi TSUDA Fuyuto TERUI Takanao SAIKI
出版者
THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
雑誌
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN (ISSN:18840485)
巻号頁・発行日
vol.12, no.ists29, pp.Pd_33-Pd_39, 2014 (Released:2014-05-28)
被引用文献数
1

A kinetic impact to the asteroid 1999 JU3 by a 300kg-class impactor spacecraft is studied. This study is a part of conceptual studies conducted within the mission design of “Hayabusa-2”, the second Japanese asteroid sample-return mission. In contrast with the finally selected “Small Carry-on Impactor(SCI)” concept, the present paper shows a feasibility of a different option, the kinetic impact by a 300kg class dedicated spacecraft. This option is valuable in terms of its scientific outcome, as the impact energy is 100 times larger than the current SCI concept. This paper discusses the feasibility of the terminal impact guidance and navigation using an onboard optical telescope. The study assumes a ground operator-in-the-loop guidance scheme, which is deemed to be the lowest development risk within the limited schedule before launch. It is shown that the ground-based terminal guidance is achievable with the accuracy of 200-300m with a realistic amount of fuel and operational load.
著者
Mario KOBALD Christian SCHMIERER Ulrich FISCHER Konstantin TOMILIN Anna PETRAROLO
出版者
THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
雑誌
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN (ISSN:18840485)
巻号頁・発行日
vol.16, no.3, pp.312-317, 2018 (Released:2018-05-04)
参考文献数
36
被引用文献数
1 5

Hybrid rocket propulsion offers inherent safety during handling and launch operations at low cost. This makes it not only attractive for space tourism applications like SpaceShipTwo but also for sounding rockets and for educational activities with students. This has been successfully demonstrated by the HyEnD student project from the University of Stuttgart: On November 8th, 2016 at 10:30 a.m. the hybrid sounding rocket HEROS 3 was launched from the Esrange Space Center to an apogee altitude of 32,300 m (106,000 ft). This set a new altitude record for European student and amateur rocketry. Furthermore, this is a world altitude record for hybrid rockets built by students. It was successfully recovered with the drogue and main parachute being released. The rocket was powered by a 10 kN design thrust hybrid rocket engine with a paraffin-based fuel and Nitrous Oxide (N2O) as the oxidizer. The combustion efficiency was verified to be above 97% in ground tests. Liquid burn time in the flight was for 15 s with an additional combustion of gaseous N2O in the blow-down mode of about 10 s. The rocket was 7.5 m long with an empty mass of about 75 kg. The rocket structure was made completely from light-weight carbon fibre and glass fibre reinforced plastic.
著者
Osamu MORI Hirotaka SAWADA Ryu FUNASE Mutsuko MORIMOTO Tatsuya ENDO Takayuki YAMAMOTO Yuichi TSUDA Yasuhiro KAWAKATSU Jun'ichiro KAWAGUCHI Yasuyuki MIYAZAKI Yoji SHIRASAWA IKAROS Demonstration Team and Solar Sail Working Group
出版者
THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
雑誌
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN (ISSN:18840485)
巻号頁・発行日
vol.8, no.ists27, pp.To_4_25-To_4_31, 2010 (Released:2011-06-14)
参考文献数
1
被引用文献数
19 39

The Japan Aerospace Exploration Agency (JAXA) will make the world's first solar power sail craft demonstration of photon propulsion and thin film solar power generation during its interplanetary cruise by IKAROS (Interplanetary Kite-craft Accelerated by Radiation Of the Sun). The spacecraft deploys and spans a membrane of 20 meters in diameter taking the advantage of the spin centrifugal force. The spacecraft weighs approximately 310kg, launched together with the agency's Venus Climate Orbiter, AKATSUKI in May 2010. This will be the first actual solar sail flying an interplanetary voyage.
著者
Yusuke SUZUKI Takane IMADA
出版者
THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
雑誌
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN (ISSN:18840485)
巻号頁・発行日
vol.12, no.ists29, pp.Tg_11-Tg_19, 2014 (Released:2014-12-26)

Japan contributes essential services to space experiments and enables human activities included as part of the international partnership of the ISS program by utilizing the HTVs (Kounotori). As the next step toword on-orbit service, JAXA has commenced technical research into cargo return from orbit. The HTV was used in research as the base design and a return vehicle was added to enhance performance. The combined vehicle is called the "HTV-R". HTV-R enables JAXA to recover various samples of experiments conducted on the ISS and equips a new return vehicle called as "HRV (HTV Return Vehicle)" for the enhanced function. The HRV will fly autonomously and conduct lifting re-entry into the atmosphere by controlling the attitude and trajectory to a predefined splashdown point. Now two types of vehicle concepts are being investigated. One uses an HTV as the base system for orbital flight and minimizes the initial cost of HTV-R program, and the other integrates the HTV components into a new vehicle, optimizing the on-orbit functions to minimize the recurring cost.
著者
Yuki FUNAMI Keisuke UCHISHIMA Shota HOMME Sayaka NISHINO Atsushi TAKANO
出版者
THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
雑誌
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN (ISSN:18840485)
巻号頁・発行日
vol.19, no.3, pp.295-303, 2021 (Released:2021-05-04)
参考文献数
27
被引用文献数
1

Hybrid rockets have the technical problem of a low fuel regression rate, which thereby causes a low fuel mass flow rate. Owing to recent developments in additive manufacturing technologies, using a solid fuel grain with a complicated geometrical port is one method for improving the flow rate. Star fractal geometry was employed as a complicated geometry. Combustion experiments using the grain with a star fractal port were performed. A conventional circular port was also tested for comparison. Local fuel regression rate, axial-direction-averaged local fuel regression rate, thrust, specific impulse and c* efficiency were evaluated. The local regression rate was high near the injector as a result of the impingement of injected oxidizer flow on the surface. While the axial-direction-averaged local regression rate of the star fractal port was slightly less than or almost comparable to that of the circular port, the thrust of the star fractal port was higher than that of the circular port because of the higher fuel mass flow rate. In addition, there was little difference in the specific impulse and c* efficiency when comparing the star fractal and circular ports. Therefore, star fractal geometry is superior to the circular port as the port geometry for hybrid rocket fuel grain.
著者
Tomoyuki NAKAJO Shusaku YAMAURA Fumiki ONOMA Mayuko SHIBAYAMA Takashi AOYAMA Yoshinobu KATO Yasutake ITO Hideyuki KATO
出版者
THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
雑誌
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN (ISSN:18840485)
巻号頁・発行日
vol.19, no.6, pp.845-854, 2021 (Released:2021-11-04)
参考文献数
32

In recent years, the movement to re-recognize starry sky as a regional resource and to utilize it as regional added value attracts many people. At the same time, however, the increase in the brightness of nighttime lighting due to the spread of LEDs etc. causes the night sky to gradually become brighter, and the situation in which the value of the starry sky is lost is also progressing. In order to protect the value of the starry sky, it is important to quantify the effects of nighttime lighting on the night sky brightness and to provide basic data useful for discussion on the balance between light pollution control and citizen life. From this point of view, we are promoting a project for protecting the starry sky by combining observation of nighttime lighting from space with nano-satellite and night sky brightness observation on the ground.
著者
Koji FUJITA Remi LUONG Hiroki NAGAI Keisuke ASAI
出版者
THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES
雑誌
TRANSACTIONS OF THE JAPAN SOCIETY FOR AERONAUTICAL AND SPACE SCIENCES, AEROSPACE TECHNOLOGY JAPAN (ISSN:18840485)
巻号頁・発行日
vol.10, no.ists28, pp.Te_5-Te_10, 2012 (Released:2012-08-30)
被引用文献数
1 7

The presence of an atmosphere on Mars signifies that an aircraft could travel in its atmosphere using the aerodynamic forces of flight. A reconnaissance aircraft offers the possibility to obtain high resolution data on a regional scale of several hundreds to thousands of kilometers, which cannot be achieved with rovers or satellites. However, conventional aircraft design cannot be applied for a Mars Airplane because of the nature of the Martian atmosphere and the constraints from transportation from Earth to Mars. This paper presents the conceptual design of a fixed-wing airplane for Mars, and the design rationale undertaken following the constraints set by the Martian environment. As a result, the main wing area was calculated to be 1.2 m2. It was folded using two hinges to be packed into an aeroshell. The proposed Mars Airplane has four notches on its main wing. They make packing easier to keep the wing area maximized, making the Mars Airplane more compact.