学会等発表 - 平山　寛

テザーのたわみを考慮した月の縦孔探査機降下システムの研究

小杉悠貴,平山寛

第69回宇宙科学技術連合講演会  (札幌)  2025年11月  -  2025年11月    日本航空宇宙学会

This paper investigates the movable area of a lunar pit exploration probe descent system using a two-dimensional model that considers the deflection caused by the tether's own weight. Lunar pits connected to lava tubes are considered promising sites for scientific exploration as they enable the easy collection of stratified rock samples from the walls and provide a thermally stable environment. Conventional descent methods employ a probe connected by a single tether, but such a configuration restricts horizontal mobility. To overcome this limitation, previous studies proposed suspending the probe from multiple anchor points. However, those studies neglected the tether’s weight and thus did not consider the effect of gravitational deflection. In this paper, we introduced the catenary curve to incorporate tether deflection into the model and derived the probe's movable region considering anchor friction and overturning conditions.

網状テザーへの微小デブリ衝突に対する生存確率の評価

平山寛

第69回宇宙科学技術連合講演会  (札幌)  2025年11月  -  2025年11月    日本航空宇宙学会

Long and thin space tethers are vulnerable to collisions of even small debris. The net-type triple tether invented by JAXA has redundancy to enhance survivability. A method to estimate the survivability of net-type triple tether was formulated in a past study by the author which defines effective cross-sectional areas and then numerically integrates the product of the area and flux of debris. The damaged state of the tether lines is quantifiable by stochastic variables, and differential equations of the variables express the progress of damage. Survivabilites are numerically calculated for several design parameters of net-type triple tether. The result shows that the diameter of tether lines and the number of segments have strong positive correlation, but the clearance between tether lines have no contribution.

網状テザーの生存確率を評価するための確率状態変数モデル

平山寛,鈴木昴星

第68回宇宙科学技術連合講演会  (姫路)  2024年11月  -  2024年11月    日本航空宇宙学会

Long and thin space tethers are vulnerable to collisions of even small debris. The net-type triple tether invented by JAXA has redundancy to enhance survivability. A method to estimate the survivability of a double-lined tether was formulated in a past study by the author which defines effective cross-sectional areas and then numerically integrates the product of the area and flux of debris. The damaged state of the tether lines is quantifiable by stochastic variables, and differential equations of the variables express the progress of damage. This study applies the method to the net-type triple tether. It enables a more accurate estimation of survivability for the net-type triple tether.

航空機電動化におけるフライホイールバッテリーモデルのサイジングの最適化

渡部恵, 沢田理帆, 平山寛

航空機システム電動化第2回ワークショップ  (秋田市)  2024年01月  -  2024年01月    秋田大学, 秋田県立大学, 立命館大学

航空機電動化における冗長アクチュエータ試験機の制御モデルの開発

沢田理帆, 渡部恵, 平山寛

航空機システム電動化第2回ワークショップ  (秋田市)  2024年01月  -  2024年01月    秋田大学, 秋田県立大学, 立命館大学

小惑星土壌コアサンプラーの先端構造による粒子の挙動のシミュレーション

秋山禄斗, 平直樹, 平山寛

第32回スペース・エンジニアリング・コンファレンス [SEC'23]  (仙北市)  2023年11月  -  2023年11月    日本機械学会 宇宙工学部門

火星極冠での走行を想定した車輪の性能測定とその考察

石塚誠人, 北真尋, 平山寛

第32回スペース・エンジニアリング・コンファレンス [SEC'23]  (仙北市)  2023年11月  -  2023年11月    日本機械学会 宇宙工学部門

静止軌道上のデブリの恒久的除去軌道のためのPatched-Conic法を用いた増速度の検討

小松健人, 平山寛

第32回スペース・エンジニアリング・コンファレンス [SEC'23]  (仙北市)  2023年11月  -  2023年11月    日本機械学会 宇宙工学部門

Satellites that have completed operations in geostationary orbit are currently inserted into a graveyard orbit 200 to 300 km higher in altitude to avoid crowding the geostationary orbit with debris. Insertion of an inoperative satellite into a graveyard orbit requires less propellant, but because it is only a temporary process, the graveyard orbit is contaminated, and there is a risk of debris collision in the graveyard orbit. In this study, the Patched-Conic method is used to determine the minimum ∆V required to permanently treat debris in a geostationary orbit rather than provisionally.

微小デブリ衝突痕の軌道上観測への深層学習の適用

平山寛, 中山元晴, 齋藤健吾

第32回スペース・エンジニアリング・コンファレンス [SEC'23]  (仙北市)  2023年11月  -  2023年11月    日本機械学会 宇宙工学部門

Information about the spatial existence of micro-sized orbital debris at high altitudes is limited because they are too small to observe from ground-based facilities and no exposed sample has been retrieved from the orbit higher than STS's. So, the assessment of collision risk is not unreliable in such a domain. Therefore, we propose a system that is equipped as a sub-payload of a spacecraft, inspects the exterior of the mother satellite, and detects impact features from the images. The system aims to detect debris impact features by deep learning, in order to enhance the operational autonomy of the system. We conducted detection experiments for simulated debris impact features on solar cells. This paper reports on the evaluation of the detection performance.

月の縦孔降下探査機における力学的解析とシステム構成の要素評価

新沢隆, 平山寛

第32回スペース・エンジニアリング・コンファレンス [SEC'23]  (仙北市)  2023年11月  -  2023年11月    日本機械学会 宇宙工学部門

航空機電動化における冗長アクチュエータの制御モデルの開発

沢田理帆, 渡部恵, 工藤大河, 平山寛

第61回飛行機シンポジウム  (北九州)  2023年11月  -  2023年11月    日本航空宇宙学会

More Electric Aircraft (MEA) has been promoted as a new innovation to the aircraft industry in recent years. This is to solve problems such as environmental impact and cost reduction in aircraft operation. This research is being undertaken with the aim of contributing to improving the reliability of control systems for Electro Mechanical Actuator (EMA) used in MEA. A simulation model of the EMA test machine was developed to effectively simulate regenerative braking due to rudder surface loads in the future, which was not possible before. The simulation results were then compared with the measured results of the test machine to validate the simulation model.

航空機用電動冗長アクチュエータの固着故障時の応答解析

平山寛, 渡部恵, 沢田理帆, 工藤大河

第61回飛行機シンポジウム  (北九州)  2023年11月  -  2023年11月    日本航空宇宙学会

This research focuses on electro-mechanical actuators for flight control surfaces, in the trend of the electrification of aircraft. Electro-mechanical systems are generally considered to have a higher failure rate than the conventional hydraulic systems for flight control. A velocity summing redundant actuator has been proposed in order to obtain sufficient reliability. In this study, the mechanical and electrical responses to a failure of the ball screw of this electro-mechanical actuator were analyzed by simulation using a MATLAB/Simulink model. Based on the results, ideas to detect and cope with the failure.

航空機電動化におけるフライホイールバッテリーモデルのサイジングの検討と評価

渡部恵, 沢田理帆, 工藤大河, 平山寛

第61回飛行機シンポジウム  (北九州)  2023年11月  -  2023年11月    日本航空宇宙学会

As demand for air transportation has increased in recent years, the environmental impact of aircraft operations has become an issue. Aircraft electrification is attracting attention as a solution to this problem. Although electromechanical actuators are expected to be adopted for aircraft electrification, there is a concern that excessive voltage increases may occur when the actuators are started and stopped. A power bus system using flywheel batteries (FWB) is being considered as a solution to this problem. This study aims to create an FWB model for model-based development of FWB and proposes a study and trial calculation of model sizing.

テザー利用を考慮した小惑星探査機とコアサンプラーの運動制御

小出凌平, 平山寛

第32回スペース・エンジニアリング・コンファレンス [SEC'23]  (仙北市)  2023年11月  -  2023年11月    日本機械学会 宇宙工学部門

網状テザーの素線同時切断を考慮した生存確率評価

平山寛

第67回宇宙科学技術連合講演会  (富山)  2023年10月  -  2023年10月    日本航空宇宙学会

Long and thin space tethers are easily severed by even a collision of small debris. The net-type triple tether invented by JAXA has redundancy to overcome the vulnerability. A method to estimate the survivability of a double-lined tether was formulated in a past study by the author which defines effective cross-sectional areas and then numerically integrates the product of the area and flux of debris. This study applies the method to the net-type triple tether. It enables a more accurate estimation of survivability for the net-type triple tether.

静止軌道上のスペースデブリの恒久的除去のためのPatched-Conic法を用いた増速度の検討

小松健人, 平山寛

第67回宇宙科学技術連合講演会  (富山)  2023年10月  -  2023年10月    日本航空宇宙学会

Currently, satellites that have completed their operations in geostationary orbit are injected into a graveyard orbit at an altitude of 200-300 km higher. Although it requires only a small ΔV, it is only a provisional treatment, which contaminates the graveyard orbit and poses the risk of debris impact. In this study, the Patched Conic Approximation is used to calculate the ΔV in order to propose orbits with a relatively small ΔV required to permanently treat the debris in a geostationary orbit rather than provisionally.

カメラ搭載モーファブルビームを用いた微小デブリ衝突痕観測方式MBDにおける制御系の開発と装置の改良

中山元晴, 齋藤健吾, 平山寛

第67回宇宙科学技術連合講演会  (富山)  2023年10月  -  2023年10月    日本航空宇宙学会

To solve the space debris problem, previous studies have attempted to obtain information on the density of micro micro-space debris by observing damaged areas on spacecraft from close range using a morphable beam device (MBD). The "MBD MBD-3" has been proposed as a system for this purpose, b ut the observation targets and methods have not been fully investigated. In this paper, we use these as a starting point to discover and solve the problems of MBD. By conducting an actual operation simulation using a satellite satellite-scale model and the MB, and e xamining the observation method, we were able to imagine the surveying operation of the MB. On the other hand, through this experiment, problems with the mechanism were also identified, and to solve them, the device was redesigned and a new MBD device incl uding the MB was fabricated. As a result of the experiment, it was confirmed that the aforementioned problems could be solved while maintaining the MB's ability to expand, contract, and deform. From the above, the observation procedure of MBD was clarified and the apparatus was improved.

月の縦孔降下探査機における運動分析とシステム構成の要素評価

新沢隆, 平山寛

第67回宇宙科学技術連合講演会  (富山)  2023年10月  -  2023年10月    日本航空宇宙学会

Lunar vertical holes are considered to be candidates for future lunar activity sites because of their thermal safety and low risk of cosmic radiation and falling meteorite. In this study, we analyzed the descent motion of the spacecraft by installing multiple anchors at the upper rim of the hole and suspending it by a tether at a height set at the anchors to indicate the area where the spacecraft can be moved. The suitable shape of the anchors was also discussed. Furthermore, we evaluated the elements of the system configuration for the attitude control of the probe and the exploration at the edge of the wall.

テザー回収を想定した小惑星探査機とコアサンプラーの運動制御

小出凌平, 平山寛

第67回宇宙科学技術連合講演会  (富山)  2023年10月  -  2023年10月    日本航空宇宙学会

A soil core sampler has been proposed as a sampler mechanism for an asteroid probe to collect soil samples while retaining the strata. The core sampler is connected to the spacecraft by a tether, and there is a risk of collision due to inertial forces during recovery. To recover the core sampler safely, we propose an attitude control system in which the core sampler and the spacecraft rotate with respect to each other and evaluate the feasibility of this system in actual operation. An attitude control model combining attitude control by reaction wheels and translation control by thrusters is constructed, feedback control is proposed, and evaluated by simulation.

火星極冠での走行を想定した車輪の測定評価と考察

石塚誠人, 北真尋, 平山寛

第67回宇宙科学技術連合講演会  (富山)  2023年10月  -  2023年10月    日本航空宇宙学会

The polar caps on Mars are covered with ice made of carbon dioxide and water. There have been many explorations of Mars for the past 60 years, but there has never been any exploration of the Martian polar caps. In this study, a wheel with less slippage and more driving force was investigated for running on ice. The wheel shape was evaluated by first measuring the static friction coefficient from the static load and friction force, and then measuring the traction force during rotation.

小惑星土壌コアサンプラーの先端構造による貫入性能評価

秋山禄斗, 平直樹,, 平山寛

第67回宇宙科学技術連合講演会  (富山)  2023年10月  -  2023年10月    日本航空宇宙学会

In recent years, space agencies have been focusing on sample return missions to solar-system bodies such as the Moon, Mars, and asteroids. In particular, since asteroids and comets contain information on the origin of the solar system, analyzing the composition of their samples will provide important clues to elucidate the history of the solar system and the formation of asteroids. It is recommended that the next asteroid exploration should have a mechanism that enables continuous sampling from the surface to the subsurface in order to understand the formation process of asteroids. However, in the sampling missions that have been operated so far, it is difficult to collect stratigraphically preserved samples due to the operational characteristics of the sampling mechanism used, and the amount of samples that can be collected is very small. Therefore, in this study, we develop a sampler that can collect stratigraphically preserved samples in order to obtain more information during the sampling process in which a sampling mechanism (sampler) is launched onto the asteroid surface and samples are collected with a tether.
We have decided to attach a sample spillage prevention mechanism to the cylindrical sampler. Previous studies have proposed an iris squeezing mechanism and a torsion box mechanism, and in order to adapt these mechanisms to the sampler we are designing, the sampler must have a certain thickness. The design must take into account the fact that the penetration rate decreases as the thickness increases.
In this study, a sampler with a diameter of 30 mm and a thickness of 10 mm was chosen as the thickness required to accommodate a sample spillage prevention mechanism. We propose to improve the penetration performance by 30 mm in diameter and 10 mm in thickness. The cylindrical sampler used in our experiments has a flat tip. We prepared two types of samplers, one with an inner taper and the other with an outer taper (each with an acute angle of 45°), and evaluated the penetration performance. The cylindrical sampler was penetrated into three kinds of simulated soils with different grain sizes, and the amount of penetration and slip angle of each sampler were checked to determine the tip shape with the highest penetration performance.

種子島ロケットコンテストからみたCanSatの教育効果

平山寛

小型衛星の科学教育利用を考える会  (能代市)  2023年08月  -  2023年08月    小型衛星の科学教育利用を考える会

Collision Avoiding Control of Space Debris Removal Satellites with Operational Satellites

Hiroshi Hirayama, Shintaro Tan

第34回宇宙技術および科学の国際シンポジウム  (久留米)  2023年06月  -  2023年06月    日本航空宇宙学会

A calculation method to estimate survivability of net like tether system is explained in this paper. Electro-dynamic tether is a candidate device to decelerate an orbital debris without propellant. Major problem on using a tether in space is its vulnerability against collisions by space debris. Some conceptual designs are proposed to enhance the survivability of tether, such as tape tether, multiline tether or net-type tether. Authors formulated survivability of multi-segmented double-line tether in preceding study. In this study, the calculation method is extended to treat a net type triple tether which has been developed for the EDT by JAXA. Procedure of the calculation is as follows. First, fatality rates of each element in net type tether are calculated by integrating differential flux multiplied by cross-sectional area, then survivabilities of each tether element are obtained as a function of time. Next, considering topology of net, probabilities along possible severing paths are summed up, and survivability of whole tether is obtained. At last, a simplified method with desirable precision and faster computation time is introduced. Numerical example shows that the net tether has much higher survivability than that of the double tether.

航空機電動化における冗長アクチュエータモデルを用いた故障時応答解析

鈴木稜典, 沢田理帆, 平山寛

日本航空宇宙学会北部支部2023年講演会ならびに第4回再使用型宇宙輸送系シンポジウム  (宮城県角田市)  2023年03月  -  2023年03月    日本航空宇宙学会北部支部

In recent years, the global warming problem, rising fuel prices, and increasing demand for air transportation have created a demand for aircraft electrification. The electrification of equipment that requires high reliability and safety, such as engine auxiliaries and flight control actuators, has not yet been realized. In this study, we developed a model in MATLAB/Simulink that can simulate failures in redundancy design, which is an issue when using an electric actuator instead of a hydraulic actuator for the rudder surface. The performance of the assumed system was then verified by simulating possible failures in the model.

航空機電動化における冗長アクチュエータ試験機の制御モデルの評価

沢田理帆, 渡部恵, 平山寛

日本航空宇宙学会北部支部2023年講演会ならびに第4回再使用型宇宙輸送系シンポジウム  (宮城県角田市)  2023年03月  -  2023年03月    日本航空宇宙学会北部支部

In recent years, research on aircraft electrification has led to the use of starter generators and electrohydraulic actuators in Boeing 787 and other aircraft to optimize energy use. However, electromechanical actuators and engine auxiliaries, which require high reliability and safety, have not yet been electrified. In this study, for the purpose of changing the rudder surface from a hydraulic actuator to an electric actuator, a test machine simulating a redundant actuator was built, and the control logic was constructed and verified for evaluation using MATLAB/Simulink and dSPACE. The experimental results confirmed that the control was able to follow the command values. Future work will include modeling the test machine to simulate regenerative braking.

静止軌道上のスペースデブリの恒久的除去軌道の検討

小松健人, 平山寛

日本航空宇宙学会北部支部2023年講演会ならびに第4回再使用型宇宙輸送系シンポジウム  (宮城県角田市)  2023年03月  -  2023年03月    日本航空宇宙学会北部支部

Currently, satellites that have completed operations in geostationary orbit are injected into graveyard orbit, 200 to 300 km higher in altitude. Although injection into a graveyard orbit requires only a small ∆V, it is only a provisional processing, and the graveyard orbit becomes congested and there is a risk of debris collision. In this study, we propose an orbit with a relatively small ∆V necessary to permanently treat debris in a geostationary orbit, rather than temporarily.

小惑星土壌コアサンプラーの貫入および層序保持に関する研究

吉元翔, 秋山禄斗, 平山寛

第66回宇宙科学技術連合講演会  (熊本)  2022年11月  -  2022年11月    日本航空宇宙学会

Asteroid soil samples provide significant information about the processes of the solar system and the origin of life. However, there is concern that the surface of the asteroid may be degraded by solar winds, so there is a need to collect samples with higher information from the interior. Therefore, we are developing a tubular sampler that can collect soil samples from deeper than 50 mm without disturbing the stratigraphy of the asteroid. In this study, we are evaluating the penetration and stratigraphic retention performance of the tubular sampler through experiments and 3D simulations. We conducted two new experiments and found that the piston structure proposed in 2021 does not have the penetration performance advantage of a smaller sampling diameter as seen in the tubular sampler. Although the penetration performance improved with decreasing the thickness of the sampler, it was found that a certain amount of penetration could be obtained by selecting a soil with low density as the sampling point even when the plate was thick.

自己位置推定と自律制御を用いた軌道上微小デブリ衝突痕観測ロボットの開発

八木宗一郎, 中山元晴, 平山寛

第10回スペースデブリワークショップ  (調布)  2022年11月  -  2022年11月    宇宙航空研究開発機構 研究開発部門

軌道上における微小デブリの存在密度情報にはデータギャップが存在する。回収した宇宙機による解析や観測が比較的困難であるSSOや静止軌道において特に顕著である。我々はこれらの軌道上にある宇宙機の観測機器の１つとして、デブリ衝突痕観測システムODIMを開発している。ODIMは搭載した宇宙機の外観のデブリ衝突痕を自律的に観測することが可能であり、その情報を集約することで微小デブリの存在密度情報の取得を目的としたシステムである。ODIMの観測部は深度カメラと外力を加えても形状維持が可能な構造材料Morphable Beam(MB)にて構成されている。課題点として、MB制御はアップリンクによる手動の操作に依存している点が挙げられる。これはMBの柔軟性によって曲げの精度が十分ではないこと、非ホロノミック系であることにより先端位置制御が容易ではことに起因している。本研究ではこれを解決するため、新たなMBを搭載した統合システムMBD-4とMBの自律制御システムの開発と評価を行った。宇宙機全体の形状データをもとに３次元的に地図情報を作成し、深層学習によって画像処理と自己位置推定技術により，MB先端位置を割り出すというものである。これにより、ODIM単体でデブリ衝突痕観測の完全な自動化が見込める。

微小デブリ衝突痕の軌道上観測装置の開発および深層学習と自律制御の適用

八木宗一郎, 中山元晴, 平山寛

第66回宇宙科学技術連合講演会  (熊本)  2022年11月  -  2022年11月    日本航空宇宙学会

This study proposes a new in-situ observation system for micro space debris impact marks, ODIM, and describes a new coordinate estimation system for creating a debris impact marks database. The newly developed debris impact scar database system combines ArUco markers and SCAN, which can detect debris impact traces in real time, and is capable of estimating coordinates with an accuracy of a few percent relative error at any imaging angle.

火星極冠での走行を想定した車輪評価と考察

石塚誠人, 平山寛

第66回宇宙科学技術連合講演会  (熊本)  2022年11月  -  2022年11月    日本航空宇宙学会

The polar caps on Mars are covered with ice made of carbon dioxide and water. There have been many explorations of Mars for the past 60 years, but there has never been any exploration of the Martian polar caps. In this study, a wheel with less slippage and more driving force was investigated for running on ice. The wheel shape was evaluated by first measuring the static friction coefficient from the static load and friction force, and then measuring the traction force during rotation.

テザー式小惑星土壌サンプラー回収時の探査機の運動制御

小出凌平, 平山寛

第66回宇宙科学技術連合講演会  (熊本)  2022年11月  -  2022年11月    日本航空宇宙学会

A soil core sampler has been proposed as a sampler mechanism for asteroid spacecraft to collect soil cores while maintaining stratification. The sampler is connected to the spacecraft by a tether, and there is a risk of collision due to inertial forces during recovery. In this study, a safe recovery method that avoids collision between the sampler and the spacecraft was investigated. An attitude control model combining attitude control by reaction wheels and translation control by thrusters was calculated, feedback control was proposed, and evaluated by simulation.

月の縦孔降下探査機における力学的分析とシステム構成に関する研究

新沢隆, 平山寛

第66回宇宙科学技術連合講演会  (熊本)  2022年11月  -  2022年11月    日本航空宇宙学会

Lunar vertical holes are considered to be candidates for future lunar activity sites because of their thermal safety and low risk of cosmic radiation and falling meteorite. In this study, we analyzed the mechanics of the spacecraft during descent by installing multiple anchors at the upper rim of the borehole and suspending the spacecraft by a tether at a certain height to indicate the area where the spacecraft can move. The shape of the anchor is also evaluated. In addition, the configuration of the system such as the attitude control of the spacecraft was discussed.

網状テザーにおける同時切断のリスク評価

丹慎太朗, 平山寛

第66回宇宙科学技術連合講演会  (熊本)  2022年11月  -  2022年11月    日本航空宇宙学会

Net-type tethers have the advantages of excellent debris removal performance, as well as redundancy and high cut resistance. However, it is difficult to evaluate the risk of severing due to the complexity of the structure compared to conventional ones. In this study, we conducted a risk assessment of multiple simultaneous severing of tethers in Net-type tethers. As a result, we will examine whether the current structural design can ignore the simultaneous cutting, and if not, we will derive a guideline for what geometrical parameters should be set to ignore the simultaneous cutting.

受動的デブリ除去衛星と稼働中衛星の衝突リスク抑制のための姿勢制御

平山寛

第66回宇宙科学技術連合講演会  (熊本)  2022年11月  -  2022年11月    日本航空宇宙学会

This paper describes analysis of a passive debris removal based on the conceptual designs, cylinder type and panel type. Expected removal numbers of small debris are calculated using the debris environment models, MASTER and ORDEM. Some ideas are introduced to shrink temporarily the cross-sectional area, in order to reduce risk of unexpected collision with operating satellites or large orbiting objects. The result of calculation shows effectiveness of the shrinking.

航空機電動化におけるフライホイールバッテリーモデルの開発と評価

渡部恵, 平山寛

第60回飛行機シンポジウム  (新潟)  2022年10月  -  2022年10月    日本航空宇宙学会

In recent years, increasing awareness of environmental issues and rising fuel prices have promoted the use of electric power in aircraft. However, the use of electro-mechanical actuators, which had been expected in the past, has not been realized. A flywheel battery (FWB) system has been proposed to achieve this. The purpose of this study is to create and validate a FWB model for model-based development of FWB.

Electromagnetic Design of Dual Winding Permanent Magnet Synchronous Motor for Electromechanical Actuators of Flight Control Systems

Yutaka Terao, Hiroshi Hirayama, Hirotaka Sugawara, Hitoshi Oyori

International Power Electronics Conference  (姫路市)  2022年05月  -  2022年05月   

This paper deals with PM motors using multipole anisotropic ring magnet for electro mechanic actuators (EMAs) of future aircraft flight control systems. The electromagnetic design via FEM software and evaluations of motor torque, losses in healthy and failure state are carried out. The results showed that even if one-phase open circuit of an inverter occurred or one-side of the 3-phase current supply system failed, the PM motor could operate at 100% of the average torque of 5.5 Nm or over 14.6 Nm, which is over 97 % of the maximum torque of 15.0 Nm.

DOI

航空機電動化におけるフライホイールバッテリーのモデルの研究と開発

猪狩匡平, 井野翔, 平山寛

日本航空宇宙学会北部支部2022年講演会ならびに第3回再使用型宇宙輸送系シンポジウム  (オンライン)  2022年03月  -  2022年03月    日本航空宇宙学会

In aircraft electrification, electric actuators have a problem that a sudden voltage rise occurs due to current backflow during operation. A system using flywheel battery (FWB) is being considered to cope with the problem, but it requires fail safe and system redundancy. In this study, we develop a flywheel battery model that simulates and introduces a detailed failure model using MATLAB/Simulink to realize a power bus system using a flywheel battery, and investigate redundancy to realize a power bus system using a flywheel battery. As a result, we were able to confirm the effectiveness of duplexing.

アンカーの摩擦と転倒を考慮した月の縦孔探査機降下システムについての研究

新沢隆, 平山寛

日本航空宇宙学会北部支部2022年講演会ならびに第3回再使用型宇宙輸送系シンポジウム  (オンライン)  2022年03月  -  2022年03月    日本航空宇宙学会

The lunar holes are considered to be a candidate site for future lunar activities because it is thermally safe and there is no risk of cosmic radiation or impacting objects. In this study, to explore the interior of the vertical hole, we set several anchors at the upper edge of the hole and set the height of the anchors to suspend the probe by tethers. It was found that the movement range of the probe was limited by the design parameters of the anchor. The shape of the anchor is discussed to make the range wider.

航空機電動化における冗長アクチュエータのモデルの研究と開発

井野翔, 猪狩匡平, 平山寛

日本航空宇宙学会北部支部2022年講演会ならびに第3回再使用型宇宙輸送系シンポジウム  (オンライン)  2022年03月  -  2022年03月    日本航空宇宙学会

Aircraft electrification has been attracting attention in recent years. One of the problems in using electric actuators for control surfaces is their fault tolerance. In this study, we developed a model of a system that is more resistant to failures on MATLAB/Simulink, and investigated its effectiveness and countermeasures by simulating its behavior in case of failure. As a result of the failure simulation using a model with a double-winding motor, it was confirmed that good operation could be continued even after a failure, and the effectiveness of the system was demonstrated.

航空機電動化における冗長アクチュエータ試験機の開発と評価

沢田理帆, 平山寛

日本航空宇宙学会北部支部2022年講演会ならびに第3回再使用型宇宙輸送系シンポジウム  (オンライン)  2022年03月  -  2022年03月    日本航空宇宙学会

In recent years, research on aircraft electrification has led to the use of starter generators and electrohydraulic actuators in Boeing 787 and other aircraft to optimize energy use. However, electromechanical actuators and engine auxiliaries, which require high reliability and safety, have not yet been electrified. In this study, a test machine simulating a redundant actuator was fabricated, and its controllability and performance were verified for the purpose of using an electric actuator instead of a hydraulic actuator for the rudder surface. As a result of the experiments, the redundant actuator test machine produced in this study was found to be highly accurate and easy to operate. In future research, we will use the control model to achieve more advanced control.

航空機電動化におけるフライホイールバッテリー試験機の開発と評価

渡部恵, 平山寛

日本航空宇宙学会北部支部2022年講演会ならびに第3回再使用型宇宙輸送系シンポジウム  (オンライン)  2022年03月  -  2022年03月    日本航空宇宙学会

In recent years, increasing awareness of environmental issues and rising fuel prices have promoted the use of electric power in aircraft. However, the use of electro-mechanical actuators, which had been expected in the past, has not been realized. A flywheel battery (FWB) system has been proposed to achieve this. The purpose of this study is to create and validate a FWB model for model-based development of FWB.

火星極冠での走行を想定した車輪形状の提案と評価

石塚誠人, 平山寛

日本航空宇宙学会北部支部2022年講演会ならびに第3回再使用型宇宙輸送系シンポジウム  (オンライン)  2022年03月  -  2022年03月    日本航空宇宙学会

The polar caps on Mars are covered with ice made of carbon dioxide and water. There have been many explorations of Mars for the past 60 years, but there has never been any exploration of the Martian polar caps. In this study, a wheel with less slippage and more driving force was investigated for running on ice. The wheel shape was evaluated by first measuring the static friction coefficient from the static load and friction force, and then measuring the traction force during rotation.

小惑星土壌コアサンプラー搭載探査機の姿勢制御に関する研究

小出凌平, 平山寛

日本航空宇宙学会北部支部2022年講演会ならびに第3回再使用型宇宙輸送系シンポジウム  (オンライン)  2022年03月  -  2022年03月    日本航空宇宙学会

A soil core sampler has been proposed as a sampler mechanism for asteroid probes to collect soil samples while maintaining the stratigraphy. The sampler is designed to be retrieved by a tether, but without tension, the tether cannot be controlled and there is a risk of collision with the spacecraft. In this study, we investigated a safe recovery method that avoids collision between the sampler and the spacecraft. We evaluated the safety of a tethered sampler and a spacecraft by applying tension to the tether so that the two samplers tumbled each other to maintain a certain distance, and by using a thruster to control the angular velocity increased by the recovery.

Collision Avoiding Control of Space Debris Removal Satellites with Operational Satellites

Noriyuki Nishijou, Hiroshi Hirayama

第33回宇宙技術および科学の国際シンポジウム  (オンライン)  2022年02月  -  2022年03月    日本航空宇宙学会

Passive removal satellites for small space debris have been studied. When they are deployed over a large area, there is a possibility that they will collide with an operating satellite instead of debris. In this study, we aim to reduce the risk of collision by temporarily folding or changing the attitude of deployed removal satellites. The debris environment model MASTER or ORDEM is used to estimate the collision risk. In addition, effect of a low-thrust collision avoidance maneuver using solar light pressure and aerodynamic force, which is suitable for large-area removal satellites, are investigated.

網状テザーの生存確率評価における切断経路及び形状パラメータの影響

丹慎太朗, 平山寛

第65回宇宙科学技術連合講演会  (オンライン)  2021年11月  -  2021年11月    日本航空宇宙学会

Electrodynamic tethers (EDTs) are currently being developed to remove the increasing amount of space debris in recent years. In addition to removal performance, tethers are required to have survivability so that they can safely complete their operational period. In this paper, we focus on "Net- type tethers", one of the tether structures currently proposed. Due to its structure, the tether is expected to have numerous cutting paths. In the study, we investigated to what extent the difference in the cutting pathway affects the survival probability.

惑星探査ローバーを模擬した工学基礎教育の遠隔授業化

平山寛

第65回宇宙科学技術連合講演会  (オンライン)  2021年11月  -  2021年11月    日本航空宇宙学会

This paper explains how a basic engineering class was adopted to a remote class in 2020. Students’ task in the class was developing a robotic rover using LEGO® blocks until 2018. Then it was modified in 2020 to be accomplished even in remote class because of COVID-19. A new task was prepared that students develop a virtual rover to explore Mars like field on a physics simulator Algodoo. The new task was successfully performed on the remote class and students learned basic process of engineering with fun. Evaluation index of the class by students indicate that the new task is better in some aspects.

深層学習を用いた微小デブリ衝突痕の軌道上観測装置の開発

八木宗一郎, 平山寛

第65回宇宙科学技術連合講演会  (オンライン)  2021年11月  -  2021年11月    日本航空宇宙学会

There is a lack of information on the density of micro space debris in orbit, and there is an urgent need to acquire such information. In this presentation, we propose a new system that enables us to observe the collision scars of micro space debris on satellites. The system consists of an industrial endoscope, a mechanism to control the endoscope, and a single board computer and the computer performs image processing by deep learning to enable flexible and autonomous inspection of the exterior. We also propose "SCAN-2", which is an improved algorithm to solve the problems of the debris observation program "SCAN", such as low recognition rate and delay. SCAN-2 achieved a significant improvement in processing speed compared to SCAN, but the accuracy of object detection did not change much.

スペースデブリ除去衛星と稼働衛星との衝突回避方法の研究

西條紀之, 平山寛

第65回宇宙科学技術連合講演会  (オンライン)  2021年11月  -  2021年11月    日本航空宇宙学会

Passive removal satellites for small space debris have been studied. When they are deployed over a large area, there is a possibility that they will collide with an operating satellite instead of debris. In this study, we aim to reduce the risk of collision by temporarily collapsing or changing the attitude of deployed removal satellites. The debris environment model MASTER or ORDEM is used to estimate the collision risk. In addition, a low-thrust collision avoidance maneuver using solar light pressure or aerodynamic force, which is suitable for large-area removal satellites, will be investigated.

層序保持構造を有する小惑星土壌コアサンプラーの貫入性能についての研究

吉元翔, 平山寛

第65回宇宙科学技術連合講演会  (オンライン)  2021年11月  -  2021年11月    日本航空宇宙学会

The composition of asteroid samples is an important clue to the history of the solar system. In this study, we added a piston structure with spring force (Stratigraphic retention structure) as an internal structure of the cylindrical sampler in order to collect stratigraphic Retention samples from the asteroid surface. We have already confirmed that this structure has some stratigraphic retention performance through experiments and simple simulations. In this study, the penetration performance of the sampler with stratigraphic retention performance was evaluated by new experiments, and it was found that the penetration performance of the sampler was about 80% higher than that of a simple cylindrical sampler. In addition, a three-dimensional simulation was created using the game engine Unity to simple simulate the free fall and penetration of the sampler into the soil.

火星極冠探査ローバー車輪の氷上および砂上での走行性能評価

岩佐侑哉, 平山寛

第65回宇宙科学技術連合講演会  (オンライン)  2021年11月  -  2021年11月    日本航空宇宙学会

Mars exploration has been greatly advanced by rovers in recent decades. However, polar ice cap areas have not been explored directly, in spite of its scientific value. From previous research, it was found that wheels with sharp spikes that pierce the ice are suitable for use on ice. In this study, driving tests were conducted to evaluate whether wheels with spikes are suitable for use on sand. The height, width, number, and angle of the spikes were varied to investigate the parameters that most affect the slip rate. As a result, the height of the spike has the most influence on the slip rate, and the slip rate varies with the contact area of the soil.

スペースデブリ除去衛星と稼働中の衛星との衝突回避方法の研究

西條紀之, 平山寛

日本航空宇宙学会北部支部2021年講演会ならびに第2回再使用型宇宙輸送系シンポジウム  (オンライン)  2021年03月  -  2021年03月    日本航空宇宙学会

Passive removal satellites for small space debris have been studied. When they are deployed over a large area, there is a possibility that they will collide with an operating satellite instead of debris. In this study, we aim to reduce the risk of collision by temporarily collapsing or changing the attitude of deployed removal satellites. The debris environment model MASTER or ORDEM is used to estimate the collision risk. In addition, a low-thrust collision avoidance maneuver using solar light pressure or aerodynamic force, which is suitable for large-area removal satellites, will be investigated.

網状テザーの切断経路を考慮した生存確率の評価

丹慎太朗, 平山寛

日本航空宇宙学会北部支部2021年講演会ならびに第2回再使用型宇宙輸送系シンポジウム  (オンライン)  2021年03月  -  2021年03月    日本航空宇宙学会

Electrodynamic tethers(EDTs) are currently being developed to remove the increasing amount of space debris in recent years. In addition to removal performance, tethers are required to have survivability so that they can safely complete their operational pe riod. In this paper, we focus on "Net type tethers", one of the tether structures currently proposed. Due to its structure, the tether is expected to have numerous cutting paths. In the study, we investigated to what extent the difference in the cutting p athway affects the survival probability.

画像処理を用いて人工衛星外観をリアルタイムに検査するシステムの開発

八木宗一郎, 平山寛

日本航空宇宙学会北部支部2021年講演会ならびに第2回再使用型宇宙輸送系シンポジウム  (オンライン)  2021年03月  -  2021年03月    日本航空宇宙学会

There are many cases of satellite failures caused by micro-debris collisions. From previous studies, it has been found that it is possible to obtain information on the density of micro-debris by conducting detailed observations of damaged areas and statistically aggregating the information. In this study, we developed a system to inspect the exterior of a satellite. The camera attached to the tip of the beam, which can be deformed freely, was controlled and image processing was performed in real time to identify the damaged area.

貫入衝撃を考慮した小惑星土壌コアサンプラーの構造についての研究

吉元翔, 平山寛

日本航空宇宙学会北部支部2021年講演会ならびに第2回再使用型宇宙輸送系シンポジウム  (オンライン)  2021年03月  -  2021年03月    日本航空宇宙学会

The composition of asteroid samples is an important clue to the history of the solar system. In this study, we aimed to collect stratigraphically preserved samples from the asteroid surface in order to obtain more information about the internal structure of the cylindrical sampler. A piston structure with a reaction force by spring force was adopted as an internal structure to prevent the sample from being disturbed by the impact of penetration when it was launched into the asteroid, and the performance was evaluated by experiments and simulations using a prototype sampler.

レーザー照射による低軌道の小型スペースデブリ除去に関する研究

金ハンソル, 平山寛

日本航空宇宙学会北部支部2021年講演会ならびに第2回再使用型宇宙輸送系シンポジウム  (オンライン)  2021年03月  -  2021年03月    日本航空宇宙学会

Consider how to remove small space debris in low orbit with artificial atmosphere or laser irradiation. The goal is to remove 10,000 debris per year between 10 and 25 years. Laser equipment is placed on the polar ground or in space, decelerates the debris to 200km or less.

航空機電動化におけるフライホイールバッテリーのモデルの研究と開発

猪狩匡平, 井野翔, 山本安彦, 菅原寛生, 大依仁, 平山寛

第58回飛行機シンポジウム  (オンライン)  2020年11月  -  2020年11月    日本航空宇宙学会

In aircraft electrification, electric actuators have a problem that a sudden voltage rise occurs due to current backflow during operation. A system using flywheel battery (FWB) is being considered to cope with the problem, but it requires fail safe and system redundancy. In this study, as a preparatory step for fail safe and system redundancy, we performed a simulation in order to develop an FWB model that can introduce a failure mode and to verify its performance. As a result, the model was developed appropriately so that the ability to supply and absorb electric power by accelerating and decelerating the rotation speed of the FWB was confirmed.

航空機電動化における冗長アクチュエータのモデルの研究と開発

井野翔, 猪狩匡平, 山本安彦, 菅原寛生, 大依仁, 平山寛

第58回飛行機シンポジウム  (オンライン)  2020年11月  -  2020年11月    日本航空宇宙学会

Aircraft electrification has been attracting attention in recent years. One of the problems on using electric actuators for steering surface is its reliability. In this study, we developed an actuator model that can simulate behavior of failures on MATLAB/Simulink to design redundant system. The developed model of a redundant actuator shows good performance to follow the command input of the steering angle from the simulation result. As a results of the failure simulations, we confirmed that the redundant actuator has expected performance against the failures.

火星極冠の氷上を走行可能な車輪の牽引力の研究

岩佐侑哉, 平山寛

第64回宇宙科学技術連合講演会  (オンライン)  2020年10月  -  2020年10月    日本航空宇宙学会

Mars exploration has been greatly advanced by rovers in recent decades. However, polar ice cap areas have not been explored directly, in spite of its scientific value. In this study, we propose four types of wheel shapes to drive on the ice. They are tested on ice, and evaluated from two points of view, friction coefficient and traction force. As a result, the wheel with sharp edge that sticks into the ice is less likely to slip, and the wheel with larger angle spikes shows greater traction force.

小惑星土壌コアサンプラーの採取性能向上の研究

平山寛, 堀井真成

第64回宇宙科学技術連合講演会  (オンライン)  2020年10月  -  2020年10月    日本航空宇宙学会

A desirable form of soil sample for planetary science is a core sample from certain depth with stratigraphy. We are developing core samplers that enable sampling from surface of asteroids, where are in microgravity environments. In this study, we improved our previous design of the sampler to enhance the amount of captured soil. The key mechanisms is an iris shutter to close an inlet of the sampler tube after the sampling phase. Performance of the new sampler has been evaluated by sampling experiments.

テザーを用いたスペースデブリ巻付け捕獲のダイナミクスとシミュレーション

王志宏, 平山寛

第64回宇宙科学技術連合講演会  (オンライン)  2020年10月  -  2020年10月    日本航空宇宙学会

In recent years, the increase of space debris has hindered space development. Many researchers are also drawing attention to how to remove space debris. In this paper, we proposed a removal method that contact, twine, and capture space debris using a tether with end masses. We designed a model and simulated this process using Abaqus. Especially, we studied the effect of projectile velocity and angle on the unfold tether and analyzed the capability of capturing by the posture of the tether and space debris.

希薄大気による微小抵抗力を考慮したテープテザーの変形に関する研究

小関森恵, 平山寛

第64回宇宙科学技術連合講演会  (オンライン)  2020年10月  -  2020年10月    日本航空宇宙学会

In this paper, we introduce our research on deformation analysis of tape tethers. The tape-like tether is expected to be easier to deploy and has better durability than the string-like tether, but it may be affected by the slight rarefied atmospheric drag. In addition, the behavior of the tether causes to degrade the accuracy of orbit prediction. Therefore we derive the equations of motion from models of the rarefied atmosphere and the tape tether. The tether is modeled as discrete mass points connected by massless springs. The equations of motion are solved numerically in two dimensional Hill frame. As a result, the deformation shows irregular deformation and chaotic phenomena, and it is excited by even a slight rarefied atmospheric drag.

ものづくり教育の遠隔授業対応のための物理シミュレータの利用

平山寛

小型衛星の科学教育利用を考える会  (オンライン)  2020年09月  -  2020年09月    小型衛星の科学教育利用を考える会

矩形筒状の小惑星土壌コアサンプラーの開発試験

平山寛, 中村壱利

第63回宇宙科学技術連合講演会  (徳島)  2019年11月  -  2019年11月    日本航空宇宙学会

A concept of soil sampler from surface of an asteroid is proposed in this study. It aims to obtain soil core keeping its stratigraphy. A prototype of the sampler is a rectangular tube to equip a retractable cover plate within inlet of the tube. The cover plate is supported by spring hinges in order to open only when soil is incoming. We conducted sampling tests for three types of simulated soils, pumice stone, silica sand and polystyrene foam beads. Sampling quantities are measured for several conditions on static load or incident velocity. It is observed that stratigraphy of the simulated soil can be preserved in some conditions.

月の縦孔内の多点懸垂移動システムの実験モデル開発

鈴木岳大, 平山寛

第63回宇宙科学技術連合講演会  (徳島)  2019年11月  -  2019年11月    日本航空宇宙学会

This paper proposes a new method to descend into lunar hole for an unmanned explorer. The vertical holes of about 50 m diameter were found on the lunar surface in 2009. A candidate method to explore is tether suspended descent, but single tethered probe is limited onlyalong vertical movement. So, we propose a lunar hole explorer that has a descending probe suspended by tethers from two or three points on a rim of the hole. The probe can move in two or three dimensionally by controlling length of each tether so that hasadvantage for geological survey on wall in the hole at close range. However it has limitation on movable region. First, the movable region was formulated from equilibrium of forces. Next the region is calculated and visualized assuming values of design parameters. Finally the movable area considering acceleration is illustrated under the set route.

能代宇宙イベントをはじめとした共同実験における企業連携と人材育成の取り組み

前田恵介, 和田豊, 堤明正, 平山寛, 永田晴紀, 秋山演亮

第63回宇宙科学技術連合講演会  (徳島)  2019年11月  -  2019年11月    日本航空宇宙学会

The 15th Noshiro Space Event was held in Noshiro city, Akita prefecture from 15 August to 23 August, 2019. Main purpose of this event is to provide opportunity of space education. Noshiro Space Event consists of hybrid rocket launches, a cansat competition, and a model rocket competition. In this paper, result of these space educations and their corporate collaboration, human resource development has been reported.

Morphable Beam 伸展変形制御装置2号機の開発

齊藤翔吾, 平山寛

第63回宇宙科学技術連合講演会  (徳島)  2019年11月  -  2019年11月    日本航空宇宙学会

This paper describes mechanism of a Morphable Beam (MB) with a camera to observe surface of satellite. Increasing number of space debris is serious problem on sustainable space development. Especially, micro debris is believed to exist in huge number but its distribution is not clearly known. Thus, we propose the mechanism to solve these problems. First, we have previously proposed a mechanism “MBD”to control the MB. We propose "MBD-2" which is an improvement on "MBD" in this paper. And then, we conducted experiments to verify its performance of extension, stowing and deformation of the MB. Results of the experiments showsthe proposed mechanism is capable to control the MB. Moreover, the "MBD-2" succeeded in stable operation and reduced the weight and size of the device compared to the "MBD". According to the proposed mechanism, in-situ surface inspection of satellite becomes possible and the density data of micro debris can be acquired.

ロケット講演会:「ロケットの話 歴史と技術」

平山寛  [招待有り]

日本機械学会2019年度年次大会  (秋田市)  2019年09月  -  2019年09月    日本機械学会

DOI

月の縦孔内の多点懸垂移動システムの力学的考察

鈴木岳大, 平山寛

日本機械学会2019年度年次大会  (秋田)  2019年09月  -  2019年09月    日本機械学会

This paper proposes a new method to descend into lunar hole for an unmanned explorer. The vertical holes of about 50 m diameter were found on the lunar surface in 2009. A candidate method to explore is tether suspended descent, but single tethered probe is limited only along vertical movement. So, we propose a lunar hole explorer that has a descending probe suspended by tethers from two or three points on a rim of the hole. The probe can move in two or three dimensionally by controlling length of each tethe r so that has advantage for geological survey on wall in the hole at close range. However it has limitation on movable region. First, the movable region was formulated from equilibrium of forces. Next the region is calculated and visualized assuming values of des ign parameters. Finally the movable area considering accelerati on is illustrated under the set route.

火星極冠の氷上走行に適した車輪形状の提案

平山寛, 大山翼

日本機械学会2019年度年次大会  (秋田)  2019年09月  -  2019年09月    日本機械学会

Mars exploration is rapidly progressing in this century by orbiters, landers and rovers. Recently, they have discovered several evidences of existence of water and water ice under the surface. Water on Mars is one of the most important subject both for useful resource and scientific interest. Especially, Mars polar caps are believed to be formed from huge amount of ice of water or carbon dioxide, and direct exploration on the polar caps by rover will bring valuable knowledge on water on Mars. However, almost all studies of Mars rovers assume Martian surface as rocky or sandy terrain, no ice. Therefor we propose design of wheels which is suitable on ice. The proposed shape has sharp spikes along both sides of cylindrical wheels to prevent slip on ice. In order to evaluate effectiveness of the proposed shape on ice, experimental models has been made by 3D printing, together with some other shapes for comparison. Result shows the proposed shapes give better friction coefficient on ice than conventional model.

Morphable Beam 伸展変形制御装置2号機の開発

齊藤翔吾, 平山寛

日本機械学会2019年度年次大会  (秋田)  2019年09月  -  2019年09月    日本機械学会

This paper describes mechanism of a Morphable Beam (MB) with a camera to observe surface of satellite. Increasing number of space debris is serious problem on sustainable space development. Especially, micro debris is believed to exist in huge number but its distribution is not clearly known. Thus, we propose the mechanism to solve these problems. First, we developed an extension and bending mechanism for the MB attached with an observation camera on the tip, which is controlled to reach target point. And then, we conducted experiments to verify i ts performance of extension, st o w ing and deformation of the MB. Results of the experiments shows that the proposed mechanism is capable to control the MB. According to the proposed mechanism, in situ su rface inspection of satellite becomes possible and the density data of micro debris can be acquired.

Motion Analysis of Capturing Space Debris using Tether

Hiroshi Hirayama, Keigo Sato

第32回宇宙技術および科学の国際シンポジウム  (福井市)  2019年06月  -  2019年06月    日本航空宇宙学会

This paper describes motion analysis of a tethered satellite which contacts to a space debris in order to capture and remove it. One of difficulties about removal of the debris is how to capture an uncooperative object. We propose a capturing method using a tether. First, a mother satellite extends a tether with a daughter satellite, after a while they will be vertically stabilized by gravity gradient torque. Next, the satellites approaches to a target object in slow relative velocity. If the tether intercept the object in appropriate condition, the tether will wind around the target while the daughter will turn around it. The daughter is assumed to have some mechanisms to catch their own tether. Two dimensional motions of the mother, daughter and target are numerically simulated in this study. Some successful motions of the daughter turning around the target are shown when the parameters are appropriate. This method of capturing is very adaptable to electro-dynamic tether (EDT), which is a promising candidate to decelerate the space debris without propellant. So, this study will contribute to the removal of the space debris.

A Study on Movement of a Multipoint Suspended Explorer in a Lunar Hole

Takehiro Suzuki, Hiroshi Hirayama

第32回宇宙技術および科学の国際シンポジウム  (福井市)  2019年06月  -  2019年06月    日本航空宇宙学会

This paper proposes a new method to descend into lunar hole for an unmanned explorer. The vertical holes of about 50 m diameter were found on the lunar surface in 2009. A candidate method to explore is tether suspended descent, but single tethered probe is limited only along vertical movement. So, we propose a lunar hole explorer that has a descending probe suspended by tethers from two or three points on a rim of the hole. The probe can move in two or three dimensionally by controlling length of each tether so that has advantage for geological survey on wall in the hole at close range. However it has limitation on movable region. First, the movable region was formulated from equilibrium of forces. Next the region is calculated and visualized assuming values of design parameters. Finally descending trajectories are proposed within the region.

A Study on Deformation of Tape Tether with Rarefied Atmospheric Drag

Morie Koseki, Hiroshi Hirayama

第32回宇宙技術および科学の国際シンポジウム  (福井市)  2019年06月  -  2019年06月    日本航空宇宙学会

This paper describes a study on deformation analysis of the tape tether. A tape shaped tether has advantages that it is easy to extend and it has better survivability, compared to conventional string shaped tether. We focus on the tape tether in this study, because there are a lot of studies on behaviour or control of the string tether but not many analysis have been done on deformation of the tape tether.Hence, we study a deformation analysis of the tape tether considering rarefied atmospheric drag. Result of the numerical simulation shows the deformation of the tape tether and overall atmospheric drag.

Extension and Deformation Control Device of Morphable Beam

Shogo Saito, Hiroshi Hirayama

第32回宇宙技術および科学の国際シンポジウム  (福井市)  2019年06月  -  2019年06月    日本航空宇宙学会

This paper describes mechanism of a Morphable Beam (MB) with a camera to observe surface of satellite. Increasing number of space debris is serious problem on sustainable space development. Especially, micro debris is believed to exist in huge number but its distribution is not clearly known, because it can be estimated only from inspection of damages on surface of objects retrieved from orbit. Thus, we propose the mechanism to solve these problems. First, we developed an extension and bending mechanism for the MB attached with an observation camera on the tip, which is controlled to reach target point. And then, we conducted three types of experiments to verify its performance of extension and deformation of the MB. Results of the experiments shows that the extension lengths and the deformations are almost proportional to control inputs. Therefore, it is considered that the proposed mechanism is capable to control the MB. According to the proposed mechanism, in-situ surface inspection of satellite becomes possible and the density data of micro debris can be acquired.

スペースデブリ捕獲における金属溶着技術の利用

吉村建, 平山寛

日本航空宇宙学会北部支部2019年講演会ならびに第20回再使用型宇宙推進系シンポジウム  (角田市)  2019年03月  -  2019年03月    日本航空宇宙学会

This paper describes consideration on capturing space debris using metal welding. Various capturing methods have been studied in the use of electro-dynamic tethers to remove space debris, but it is difficult to fabricate a mechanism suitable for various moments and conditions. On the other hand, laser welding technology has developed dramatically in recent years, and efficient welding in vacuum can be expected. In this study, the feasibility of the fixing method of space debris by welding is investigated by heat conduction simulation. From this research, welding can be proposed as one of method to capture space debris.

小惑星土壌コアサンプラーの研究

中村壱利, 平山寛

日本航空宇宙学会北部支部2019年講演会ならびに第20回再使用型宇宙推進系シンポジウム  (角田市)  2019年03月  -  2019年03月    日本航空宇宙学会

In this research, we conducted a study on a sampler that enables soil core sampling on asteroids, which are microgravity environments. Dropping experiments, static loading experiments and sampling experiments of simulated strata were carried out to describe the superiority of the sampling-capable mechanism while maintaining stratigraphy, which is the greatest characteristic of this mechanism. In addition, when comparing the relationship between the sampling amount and the penetration depth in the drop experiment and the static load experiment, it was also found that the sampling with the static load is more efficient because the sampled quantity related to the penetration depth is larger.

希薄大気抵抗によるテープテザーの変形に関する研究

小関森恵, 平山寛

日本航空宇宙学会北部支部2019年講演会ならびに第20回再使用型宇宙推進系シンポジウム  (角田市)  2019年03月  -  2019年03月    日本航空宇宙学会

This paper describes a study on deformation analysis of the tape tether. A tape shaped tether has advantages that it is easy to extend and it has better survivability, compared to conventional string shaped tether. We focus on the tape tether in this study, because there are a lot of studies on behaviour or control of the string tether but not many analysis have been done on deformation of the tape tether. Hence, we study a deformation analysis of the tape tether considering rarefied atmospheric drag. Result of the numerical simulation shows the deformation of the tape tether and overall atmospheric drag.

火星極冠の氷上を走行可能な車輪の形状の提案

大山翼, 平山寛

日本航空宇宙学会北部支部2019年講演会ならびに第20回再使用型宇宙推進系シンポジウム  (角田市)  2019年03月  -  2019年03月    日本航空宇宙学会

Mars exploration is rapidly progressing in this decade by orbiters, landers and rovers. Recently, they have discovered several evidences of existence of water and water ice under the surface. Water on Mars is one of the most important subject both for useful resource and scientific interest. Especially, Mars polar caps are believed to be formed from huge amount of ice of water or carbon dioxide, and direct exploration on the polar caps by rover will bring valuable knowledge on water on Mars. However, almost all studies of Mars rovers assume Martian surface as rocky or sandy terrain, no ice. Therefor we propose design of wheels which is suitable on ice. The proposed shape has sharp spikes along both sides of cylindrical wheels to prevent slip on ice. In order to evaluate effectiveness of the proposed shape on ice, experimental models has been made by 3D printing, together with some other shapes for comparison. Result shows the proposed shapes give better friction coefficient on ice than conventional model.

スペースデブリ捕獲のための小型展開エンドエフェクタ

平山寛, 大谷裕樹

第62回宇宙科学技術連合講演会  (久留米)  2018年10月  -  2018年10月    日本航空宇宙学会

This paper describes development of a small end effector to capture space debris. It is assumed to be installed at a tip of manipulator arm or an end of tether. The most remarkable feature of the end effector is its deployable fingers. Each element of the fingers are retracted into next element from the tip to the bottom so that the fingers are stowed in compact palm unit. Motion of deployment and holding force of the fingers are driven by tension of wires along the fingers. Results of three types of experiments are explained in the paper, two dimensional capture region test, vertical pinching force test and vertical holding load test.

電磁石を用いた宇宙構造物の展開機構

平山寛, 根本雄平

第62回宇宙科学技術連合講演会  (久留米)  2018年10月  -  2018年10月    日本航空宇宙学会

This paper introduces development of a deployable structure driven by electromagnets. This study aims to provide deployable beam used for a large space structure such as a space solar power satellite. First, we designed a scale model of a deployable beam with electromagnets, and then built one segment of the beam. Next, deployment of single longitudinal element was tested. Finally, deployment of the beam segment was verified. Results of the experiment show that the structure can be deployed by the force of electromagnets and it requires some modifications to improve its performance.

能代宇宙イベントをはじめとした宇宙教育活動における安全管理と企業連携

前田恵介, 和田豊, 堤明正, 平山寛, 永田晴紀, 秋山演亮

第62回宇宙科学技術連合講演会  (久留米)  2018年10月  -  2018年10月    日本航空宇宙学会

The 14th Noshiro Space Event was held in Noshiro city, Akita prefecture from 16 August to 23 August, 2018. Main purpose of this event is to provide opportunity of space education. Noshiro Space Event consists of hybrid rocket launches, a cansat competition, and a model rocket competition. In this paper, result of these space educations and their safety management, corporate collaboration has been reported.

Morphable Beam 伸展変形制御装置

齊藤翔吾, 平山寛

第62回宇宙科学技術連合講演会  (久留米)  2018年10月  -  2018年10月    日本航空宇宙学会

This paper describes mechanism of a Morphable Beam (MB) with a camera to observe surface of satellite. Increasing number of space debris is serious problem on sustainable space development. Especially, micro debris is believed to exist in huge number but its distribution is not clearly known, because it can be estimated only from inspection of damages on surface of objects retrieved from orbit. Thus, we propose the mechanism to solve these problems. First, we developed an extension and bending mechanism for the MB attached with an observation camera on the tip, which is controlled to reach target point. And then, we conducted three types of experiments to verify its performance of extension and deformation of the MB. Results of the experiments shows that the extension lengths and the deformations are almost proportional to control inputs. Therefore, it is considered that the proposed mechanism is capable to control the MB. According to the proposed mechanism, in-situ surface inspection of satellite becomes possible and the density data of micro debris can be acquired.

月の縦孔内の多点懸垂移動システムの力学的考察

鈴木岳大, 平山寛

第62回宇宙科学技術連合講演会  (久留米)  2018年10月  -  2018年10月    日本航空宇宙学会

This paper proposes a new method to descend into lunar hole for an unmanned explorer. The vertical holes of about 50 m diameter were found on the lunar surface in 2009. A candidate method to explore is tether suspended descent, but single tethered probe is limited only along vertical movement. So, we propose a lunar hole explorer that has a descending probe suspended by tethers from two or three points on a rim of the hole. The probe can move in two or three dimensionally by controlling length of each tether so that has advantage for geological survey on wall in the hole at close range. However it has limitation on movable region. First, the movable region was formulated from equilibrium of forces. Next the region is calculated and visualized assuming values of design parameters. Finally descending trajectories are proposed within the region.

第13回能代宇宙イベントにおける実践的宇宙教育の成果と今後の展望

堤明正, 平山寛, 和田豊, 前田恵介, 秋山演亮

日本航空宇宙学会北部支部2018年講演会ならびに第19回再使用型宇宙推進系シンポジウム  (仙台市)  2018年03月  -  2018年03月    日本航空宇宙学会

The 13th Noshiro Space Event was held in Noshiro city, Akita prefecture from 17 August to 24 August, 2017. Main purpose of this event is to provide opportunity of practical space education. Noshiro Space Event consists of hybrid rocket launches, a cansat competition, and a model rocket competition. In this paper, result of these practical educations has been reported.

第13回能代宇宙イベントにおける実践的宇宙教育の実施結果と将来展望

堤明正, 平山寛, 和田豊, 前田恵介, 秋山演亮

第61回宇宙科学技術連合講演会  (新潟市)  2017年10月  -  2017年10月    日本航空宇宙学会

The 13th Noshiro Space Event was held in Noshiro city, Akita prefecture from 17 August to 24 August, 2017. Main purpose of this event is to provide opportunity of practical space education. Noshiro Space Event consists of hybrid rocket launches, a cansat competition, and a model rocket competition. In this paper, result of these practical educations has been reported.

Attitude Control Simulator for the Small Satellite and Its Validation by On-orbit Data of QSAT-EOS

Masayuki Katayama, Yuta Suzaki, Shigeru Aso, Hiroshi Hirayama

AIAA/USU Conference on Small Satellites  (Logan, Utah, USA)  2017年08月  -  2017年08月    AIAA/USU

The role of the microsatellites has become significant due to the progress of performance and miniaturization of the electronics devices. For the purpose of earth observation the constellation flight of the microsatellites has made it possible to obtain the continuous data of the designated location and it is expected that the data be utilized in wide variety of the filed such as science, agriculture, industries, and climate monitoring. As the microsatellites take the LEO, the time of observation on the designated location is limited. Therefore the agile and precise pointing performance is required so as the attitude control accuracies. This paper presents the development of the attitude control simulator for the microsatellite for the use of design of the attitude control subsystem. Quaternion feedback control is proved to be effective and stable. Then the on-orbit data of the QSAT-EOS (Kyushu Satellite for Earth Observation System Demonstration) is analyzed to confirm the effectiveness of the quaternion feedback control. QSAT-EOS was launched in 2014 and now is in the deorbit phase after two year operation. Results of the on-orbit data analysis have suggested some necessities of improvement of the simulator and control algorithm which are the future subject.

超小型衛星QSAT-EOS（つくし）の宇宙工学教育利用

平山寛, 麻生茂, 森下和彦, 藤崎清孝, 八坂哲雄, 大西俊輔

第60回宇宙科学技術連合講演会  (函館)  2016年09月  -  2016年09月    日本航空宇宙学会

QSAT-EOS (Tsukushi) is a micro satellite which was developed by universities and local industries in Kyushu area of Japan. It was launched in November 2014 from Russia. Since then, the satellite is being operated mainly by staffs and volunteer students of Kyushu university. This activity motivates the students to study special knowledge about astronautics and satellite communication even before they learn them in ordinary courses. This paper introduces an organization of the operation group, then remarks on education effect to the students.

超小型衛星QSAT-EOS（つくし）の姿勢制御結果の考察

平山寛,八坂哲雄,日南川英明,桜井晃,麻生茂,森下和彦

第60回宇宙科学技術連合講演会  (函館)  2016年09月  -  2016年09月    日本航空宇宙学会

QSAT-EOS (Tsukushi) is a micro satellite which was developed by universities and local industries in Kyushu area of Japan. It was launched in November 2014 from Russia. Primary mission of the satellite is optical imaging of Earth surface. Therefore, it has 3-axes attitude control capability in order to point a camera to a subject area also point its antenna to a ground station. The satellite succeeded to control its attitude in orbit. This paper introduces attitude control system of QSAT-EOS, then shows some results of attitude controlling.

QSAT-EOS（つくし）打ち上げ状況

麻生茂, 平山寛, 森下和彦, 藤崎清孝, 谷泰寛, 八坂哲雄, 大西俊輔

九州小型衛星の会(QSSF)平成27年度研究会  (福岡市)  2016年03月  -  2016年03月    九州小型衛星の会

九州大学における小型衛星QSAT-EOS（つくし）の運用体制

平山寛

第2回小型衛星の科学教育利用を考える会  (平塚市)  2016年03月  -  2016年03月    小型衛星の科学教育利用を考える会