Acta Astronautica最新文献

Improving landing stability and terrain adaptability in Lunar exploration with biomimetic lander design and control 利用仿生着陆器的设计和控制提高月球探测的着陆稳定性和地形适应性

IF 3.1 2区物理与天体物理

Acta Astronautica Pub Date : 2024-11-14 DOI: 10.1016/j.actaastro.2024.11.020

Jinyao Zhu , Jia Ma , Jinbao Chen , Chen Wang , Yunfeng Li , Zhihao Fan , Chaoyu Lu

{"title":"Improving landing stability and terrain adaptability in Lunar exploration with biomimetic lander design and control","authors":"Jinyao Zhu , Jia Ma , Jinbao Chen , Chen Wang , Yunfeng Li , Zhihao Fan , Chaoyu Lu","doi":"10.1016/j.actaastro.2024.11.020","DOIUrl":"10.1016/j.actaastro.2024.11.020","url":null,"abstract":"<div><div>Traditional lunar landers face challenges due to strict flatness requirements at landing sites and the need to avoid complex terrains, which significantly limits their exploration capabilities and success rates. Additionally, their focus on stable landings often compromises their maneuverability, reducing adaptability to various lunar terrains. To address these issues, this study introduces a walkable cat-legged lander (WCLL) inspired by feline landing mechanisms. The WCLL integrates features from both traditional landers and rovers, enabling it to perform high-load landings and navigate effectively across diverse lunar surfaces. It utilizes magnetorheological dampers to dissipate impact energy and employs a soft-landing control method, achieving stable landings under various conditions, including vertical velocities of 3 m/s, payloads of 1280 kg, slopes of 15°, and horizontal disturbances at speeds of 2 m/s. Compared to the Chang'e−3 lander, the WCLL shows a 66.7 % increase in slope adaptability and a 22.6 % improvement in resistance to horizontal disturbances. Finally, experimental validation confirms the accuracy of the simulation model, providing valuable insights for future lunar exploration robot design.</div></div>","PeriodicalId":44971,"journal":{"name":"Acta Astronautica","volume":"226 ","pages":"Pages 860-875"},"PeriodicalIF":3.1,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142702666","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Vision-based navigation and obstacle detection flight results in SLIM lunar landing 基于视觉的导航和障碍物探测飞行实现了 SLIM 月球着陆

IF 3.1 2区物理与天体物理

Acta Astronautica Pub Date : 2024-11-13 DOI: 10.1016/j.actaastro.2024.11.002

Takayuki Ishida , Seisuke Fukuda , Kazuki Kariya , Hiroyuki Kamata , Keiki Takadama , Hirohisa Kojima , Shujiro Sawai , Shinichiro Sakai

引用次数: 0

On the two approaches for the combustion instability predictions in a long-flame combustor 长火焰燃烧器燃烧不稳定性预测的两种方法

IF 3.1 2区物理与天体物理

Acta Astronautica Pub Date : 2024-11-12 DOI: 10.1016/j.actaastro.2024.10.069

Xiaokang Liu , Xiaolin Xiang , Xiaoyu Yu , Qingfei Fu , Lijun Yang , Jingxuan Li

{"title":"On the two approaches for the combustion instability predictions in a long-flame combustor","authors":"Xiaokang Liu , Xiaolin Xiang , Xiaoyu Yu , Qingfei Fu , Lijun Yang , Jingxuan Li","doi":"10.1016/j.actaastro.2024.10.069","DOIUrl":"10.1016/j.actaastro.2024.10.069","url":null,"abstract":"<div><div>This paper presents a detailed comparative analysis and discussion of two typical predictive methods for combustion instability in long flame combustion chambers: the coupled method and the decoupled method. Using large eddy simulation (LES), the coupled method directly predicts stability in typical long flame combustion chambers. In the decoupled method, stability in the combustion chamber is predicted by combining a low-order acoustic network for long flames with flame responses and mean parameters from numerical simulations. The research results indicate that the coupled method provides full-field information, while the decoupled method neglects certain factors, such as the coupling between combustion and acoustics. However, the decoupled method can directly determine combustion instability based on the growth rate of oscillation modes. The flow field undergoes periodic changes, with the region of fluctuation in the combustion heat release rate gradually increasing, resembling vortex development, which ruptures upon encountering the wall due to radial constraints. Furthermore, in the decoupled method, the periodic changes in the flow field are controlled by the frequency of incoming flow disturbances, whereas in the coupled method, they are controlled by the acoustic frequency of the combustion chamber. In the coupled method, the coupling among disturbances and the acoustic disturbances at the boundaries amplifies the disturbances, causing the radial scale of the fluctuation region in the combustion heat release rate to increase along the axial direction and approach a fixed value faster than in the decoupled method.</div></div>","PeriodicalId":44971,"journal":{"name":"Acta Astronautica","volume":"226 ","pages":"Pages 814-826"},"PeriodicalIF":3.1,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Investigation of discharge voltage characteristics of a lanthanum hexaboride heaterless hollow cathode 六硼化镧无加热器空心阴极放电电压特性的研究

IF 3.1 2区物理与天体物理

Acta Astronautica Pub Date : 2024-11-12 DOI: 10.1016/j.actaastro.2024.11.018

Yi-Lung Huang , Jordan H. Hsieh , Wei-Cheng Wang , Yueh-Heng Li

{"title":"Investigation of discharge voltage characteristics of a lanthanum hexaboride heaterless hollow cathode","authors":"Yi-Lung Huang , Jordan H. Hsieh , Wei-Cheng Wang , Yueh-Heng Li","doi":"10.1016/j.actaastro.2024.11.018","DOIUrl":"10.1016/j.actaastro.2024.11.018","url":null,"abstract":"<div><div>This study investigated the discharge voltage characteristics of an argon-fed lanthanum hexaboride heaterless hollow cathode to assess the influence of flow rate, discharge current, background pressure, and applied magnetic field strength. Decreasing the flow rate from 15 to 3 sccm led to a considerable increase in discharge voltage and peak-to-peak oscillation, particularly for flow rates below 5 sccm. Subsequently, variation in discharge current was tested at 4–7 A; this test revealed that the discharge voltage decreases from 53 to 48 V as the discharge current increases, while the peak-to-peak oscillation increases by approximately 2 V with the rise in discharge current. At high background pressures (8.1 × 10<sup>−4</sup> Torr), the discharge voltage decreased by 15 V, and the peak-to-peak oscillation was maintained at 5 V. Furthermore, the spectral analysis of the discharge voltage indicated the occurrence of high-energy oscillations at 10–500 kHz owing to ionization instability. The discharge voltage decreased when the strength of an externally applied axial magnetic field increased from 0 to 118 G. Such a result can be attributed to increased ionization (caused by the applied magnetic field) in the emitter and cathode-keeper region, thereby decreasing sheath potential on the emitter surface.</div></div>","PeriodicalId":44971,"journal":{"name":"Acta Astronautica","volume":"226 ","pages":"Pages 760-771"},"PeriodicalIF":3.1,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Extreme translational impact of triple-shock configurations of blast waves in a confined volume of an orbital station 爆炸波三重冲击构型在轨道站密闭空间内的极端平移影响

IF 3.1 2区物理与天体物理

Acta Astronautica Pub Date : 2024-11-10 DOI: 10.1016/j.actaastro.2024.11.017

M.V. Chernyshov, K.E. Savelova

{"title":"Extreme translational impact of triple-shock configurations of blast waves in a confined volume of an orbital station","authors":"M.V. Chernyshov, K.E. Savelova","doi":"10.1016/j.actaastro.2024.11.017","DOIUrl":"10.1016/j.actaastro.2024.11.017","url":null,"abstract":"<div><div>The translational effects of gas streams, which form after the triple-shock configurations at Mach reflection of blast waves with normal main shock (so-called stationary Mach configurations), were analyzed. Unlike in the case of an elevated explosions of fuel as rocket starts in initially stagnant air, which is considered here as a private case, it was supposed that this shock-wave structure moves in a preceding flow with arbitrary velocity (and corresponding flow Mach number). Analyzing relations of the dynamic pressures across the slipstream, which emanates from the triple point of the Mach reflection, it was shown that the flows after the triple-shock configuration usually differ much in their translational action on surrounding objects. It was found and discussed that some configurations drag the objects initially situated above and below the triple-point trajectory in opposite directions. Moreover, the “trigger” structure was found that remains previous flow drag action on the object above the triple-point trajectory, but switches it to exactly opposite one, if the object is situated below the triple point.</div></div>","PeriodicalId":44971,"journal":{"name":"Acta Astronautica","volume":"226 ","pages":"Pages 876-891"},"PeriodicalIF":3.1,"publicationDate":"2024-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142702601","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of particle size on gasification of solid fuel in a low-temperature gas generator 粒度对低温气体发生器中固体燃料气化的影响

IF 3.1 2区物理与天体物理

Acta Astronautica Pub Date : 2024-11-10 DOI: 10.1016/j.actaastro.2024.11.016

M.V. Salganskaya, A. Yu Zaichenko, D.N. Podlesniy, M.V. Tsvetkov, Yu Yu Tsvetkova, E.A. Salgansky

引用次数: 0

Corrigendum to ‘Orbit determination for spacecraft with continuous low-thrust using nonsingular Thrust-Fourier-Coefficients and filtering-through approach’ [Acta Astronaut. 224 November 2024, 353–366, AA_10602] 利用非正弦推力-傅里叶系数和滤过法确定连续低推力航天器的轨道"[Acta Astronaut. 224 November 2024, 353-366, AA_10602] 更正

IF 3.1 2区物理与天体物理

Acta Astronautica Pub Date : 2024-11-09 DOI: 10.1016/j.actaastro.2024.10.068

Jidan Zhang , Tinglei Zhu , Changyin Zhao

引用次数: 0

In-flight calibration of the MEDA-TIRS instrument onboard NASA's Mars2020 mission 美国国家航空航天局火星 2020 飞行任务搭载的 MEDA-TIRS 仪器的飞行中校准

IF 3.1 2区物理与天体物理

Acta Astronautica Pub Date : 2024-11-09 DOI: 10.1016/j.actaastro.2024.11.015

Eduardo Sebastián , Germán Martínez , Miguel Ramos , Michael D. Smith , Verónica Peinado , Luis Mora , Mark T. Lemmon , Álvaro de Vicente-Retortillo , Javier de Lucas , Ricardo Ferrándiz , José A. Rodríguez-Manfredi

{"title":"In-flight calibration of the MEDA-TIRS instrument onboard NASA's Mars2020 mission","authors":"Eduardo Sebastián , Germán Martínez , Miguel Ramos , Michael D. Smith , Verónica Peinado , Luis Mora , Mark T. Lemmon , Álvaro de Vicente-Retortillo , Javier de Lucas , Ricardo Ferrándiz , José A. Rodríguez-Manfredi","doi":"10.1016/j.actaastro.2024.11.015","DOIUrl":"10.1016/j.actaastro.2024.11.015","url":null,"abstract":"<div><div>This article describes a novel procedure and algorithm used for the in-flight calibration of the Thermal Infrared Sensor (TIRS) onboard the Mars 2020 mission. The purpose is to recalibrate the responsivity of TIRS’ IR detectors as they degrade following surface operations and exposure to harsh environmental conditions. Using data from in-flight calibration campaigns conducted through sol 800 of this mission, we report the time evolution of the responsivity for the different IR detectors, as well as the final performance achieved by the algorithm in the real operating environment. Moreover, we analyzed changes in responsivity as a function of TIRS geometric design and environmental factors, e.g., detector orientation, direct exposure to prevailing winds and solar radiation, electrostatic properties of the detector filter, and atmospheric dust concentration. We concluded that dust deposition on the detectors' filter during landing, and later during operation is the most likely cause of the degradation observed in the various channels, with gravitational sedimentation and the capacity of the filters to accumulate electrostatic charge being key factors. The relative and absolute degradation of the TIRS is similar to those reported by other Martian missions and instruments with similar orientations, and to date, it has shown no signs of cleaning after more than a year on the surface of Mars. Accounting for changes in responsivity during the mission is critical to maintaining the reliability of TIRS measurements, which will later be made available in NASA's Planetary Data System for the benefit of the scientific community.</div></div>","PeriodicalId":44971,"journal":{"name":"Acta Astronautica","volume":"226 ","pages":"Pages 791-802"},"PeriodicalIF":3.1,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Robust solar sail trajectories using proximal policy optimization 利用近端策略优化实现稳健的太阳帆轨迹

IF 3.1 2区物理与天体物理

Acta Astronautica Pub Date : 2024-11-09 DOI: 10.1016/j.actaastro.2024.10.065

Christian Bianchi, Lorenzo Niccolai, Giovanni Mengali

{"title":"Robust solar sail trajectories using proximal policy optimization","authors":"Christian Bianchi, Lorenzo Niccolai, Giovanni Mengali","doi":"10.1016/j.actaastro.2024.10.065","DOIUrl":"10.1016/j.actaastro.2024.10.065","url":null,"abstract":"<div><div>Reinforcement learning is used to design minimum-time trajectories of solar sails subject to the typical sources of uncertainty associated with such a propulsion system, i.e., inaccurate knowledge of the sail’s optical properties and the presence of wrinkles on the sail membrane. A proximal policy optimization (PPO) algorithm is used to train the agent and derive the control policy that associates the optimal sail attitude with each dynamic state. First, the agent is trained assuming deterministic unperturbed dynamics, and the results are compared with optimal solutions found by an indirect optimization method, thus demonstrating the effectiveness of this approach. Next, two stochastic scenarios are analysed. In the first, the optical coefficients of the sail are assumed to be random variables with Gaussian distribution, which leads to random variations in the sail characteristic acceleration. In the second scenario, wrinkles on the sail membrane are taken into account, resulting in a misalignment of the thrust vector with respect to a perfectly smooth surface. Both phenomena are modelled based on experimental measurements available in the literature in order to perform realistic analyses. In the stochastic scenarios, Monte Carlo simulations are performed using the trained policies, demonstrating that the reinforcement learning approach is capable of finding near time-optimal solutions, while also being robust to the sources of uncertainty considered.</div></div>","PeriodicalId":44971,"journal":{"name":"Acta Astronautica","volume":"226 ","pages":"Pages 702-715"},"PeriodicalIF":3.1,"publicationDate":"2024-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142661036","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effective compliance to technical regulations - Why is compliance to the orbital debris mitigation rules so poor? 有效遵守技术条例--为什么遵守轨道碎片缓减规则的情况如此糟糕？

IF 3.1 2区物理与天体物理

Acta Astronautica Pub Date : 2024-11-09 DOI: 10.1016/j.actaastro.2024.11.013

David B. Spencer , Didier Alary , Valentin Eder , Peter Martinez , Stijn Lemmens , Kawamoto Satomi , Morgane Lecas , Jose María Hermoso

引用次数: 0