学会等発表 - 平山　寛

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

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

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

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.

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.