检索结果-内蒙古大学图书馆

AAS/AIAA Astrodynamics Specialist Conference, 2020

作者： Craig, A.S. Hauglie, J.E. Hawkins, M.J. Hays, J.J. EV42/Guidance Navigation and Mission Design Branch NASA Marshall Space Flight Center HuntsvilleAL35812 United States Jacobs Engineering Jacobs ESSCA Group HuntsvilleAL35812 United States

ISBN: (纸本)9780877036753

NASA’s Space Launch system (SLS) is being developed with the primary purpose of returning people to the Moon and eventually landing people on Mars. With these lofty goals, ensuring mission completion is paramount even in the event of an in-flight mishap. One possible mishap is the loss of an engine in flight. While SLS was not required to show full engine out capability, the program took an "assess to" approach to see when the launch vehicle could complete the mission after an engine failure versus when the launch vehicle targets required a down-mode to an alternate mission target to ensure at least some flight objectives were complete, or at a minimum ensure safe return of Orion and the Crew. While this paper will focus on Artemis I, an uncrewed mission, some comparisons will be made to how the engine out capability will change for the subsequent Crewed flights of SLS and Orion. © 2021, Univelt Inc. All rights reserved.

关键词： Launch vehicles

来源：评论

学校读者我要写书评

暂无评论

Analysis on Stability of Three-loop Autopilot with An Acceleration Feedback Augmentation Loop

Analysis on Stability of Three-loop Autopilot with An Accele...

引用

第40届中国控制会议

作者： Hui Wang Tao Li Daoguang Tang Junfang Fan Yifang Yuan Luyao Zang Wugang Wang Chunyan Xiao School of Aerospace Engineering Beijing Institute of Technology Beijing Key Laboratory of UAV Autonomous Control Beijing Institute of Technology School of Electrical and Control Engineering North University of China Beijing Key Laboratory of High-Dynamic Navigation Technology Beijing Information Science and Technology University China PLA 63961 Unit Beijing System Design Institute of Electro-Mechanic Engineering Northwest Industries Group CO. Ltd.

In order to construct a stable augmentation loop, a novel three-loop autopilot structure with an acceleration feedback is proposed. Based on LQR and analytical methods, the design process of the controller parameters is deduced. For a static unstable missile, the control characteristics of a three-loop autopilot with acceleration feedback are compared with classical three-loop and pseudo-angle-of-attack feedback three-loop autopilots. It is pointed out that the closed-loop gain of the three-loop autopilot with acceleration signal feedback is 1, which is not affected by the control parameters. The autopilot can control the static unstable missile, and the acceleration signal is easier to obtain than the pseudo-angle-of-attack.

关键词： Acceleration feedback Stable augmentation loop Autopilot Static unstable missile

来源：评论

学校读者我要写书评

暂无评论

Research on fault diagnosis technology based on FD-GT method

引用

International Journal of Information and Communication Technology 2020年第3期16卷 261-274页

作者： Kang, Weijie Xiao, Jiyang Xiao, Mingqing Tang, Xilang Hu, Bin Automatic Test System Lab Aeronautical Engineering College Air Force Engineering University No. 1 Baling Road Baqiao District Xi'an Shaanxi China Operational Design and Mission Planning Lab Air Traffic Control and Navigation College Air Force Engineering University No. 1 East Changle road Baqiao District Xi'an Shaanxi China Xiangtan Branch China Mobile Communications Corporation Number 1 Dahu road Xiangtan Hunan China

Fault diagnosis can be divided into two main tasks: fault feature extraction and fault data classification. Firstly, aiming at the problem that the fault feature extraction method is not significant, this paper proposes a fault feature extraction method based on fuzzy distance (FD). The initial fuzzy distance calculation method is established by expert knowledge. The key parameters of fuzzy distance are optimised based on DE algorithm combined with historical test data. Secondly, aiming at the problem of low accuracy when classifying fault data, this paper proposes a fault data classification method based on grey target (GT) decision. The fault data classification is realised by calculating the target distance of each fault type with the current input signal set. Finally, the fuzzy distance- grey target (FD-GT) method is verified by an example. The results show that it can achieve more efficient and reliable fault diagnosis. Copyright © 2020 Inderscience Enterprises Ltd.

关键词： Failure analysis

来源：评论

学校读者我要写书评

暂无评论

Defending the earth from long-period comets and sneaky asteroids: Short term threat response requires long term preparation

引用

Journal of Space Safety engineering 2018年第3-4期5卷 197-202页

作者： Nuth, Joseph A. Barbee, Brent Leung, Ronald Solar System Exploration Division NASA's Goddard Space Flight Center Code 690 Greenbelt 20771 MD United States Navigation and Mission Design Branch NASA's Goddard Space Flight Center Code 595 Greenbelt 20771 MD United States Instrument/Payload Systems Engineering Branch NASA's Goddard Space Flight Center Code 592Code 690 Greenbelt 20771 MD United States

Comets, such as the recent Comet C/2013 A1 (Siding Spring) can impact terrestrial planets with very short warning times: for Siding Spring the time from discovery to closest approach to Mars (135,000 km) was less than 22 months. Short warning times are also possible for certain asteroids approaching on unfavorable orbits, e.g., from the direction of the Sun. The time required to design, build, test and launch a high-reliability Interceptor spacecraft is on the order of 5 years, a timescale incompatible with threat mitigation for such short warning times. A potential solution is to build the interceptor before the threat is detected and put it into storage until it is required. Launch of a stored spacecraft could be accomplished in much less than a year after authorization based on experience with the DSCOVR (Deep Space Climate Observatory) program managed by NASA's Goddard Space Flight Center. While asteroidal impacts are of order 100 times more likely than cometary impacts, comet impacts can carry more than 100 times the energy of a typical asteroid threat, making their destructive power nearly equal. Cometary threats have been largely ignored to date, a situation that needs to change as our Planetary Defense efforts become more mature. An idealized threat response system will be described. © 2018

关键词： Comet threats High-reliability spacecraft – authorization to launch Idealized response program Short-warning impactor response

来源：评论

学校读者我要写书评

暂无评论

mission design analysis for the martian moon phobos: Close flybys, missed thrusts, and other in-flight entertainment

Mission design analysis for the martian moon phobos: Close f...

引用

AAS/AIAA Astrodynamics Specialist Conference, ASC 2015

作者： Stuart, Jeffrey McElrath, Tim Petropoulos, Anastassios Navigation and Mission Design System Engineering Group Mission Design and Navigation Section Jet Propulsion Laboratory California Institute of Technology 4800 Oak Grove Drive PasadenaCA91109 United States Outer Planet Mission Analysis Group Mission Design and Navigation Section Jet Propulsion Laboratory California Institute of Technology 4800 Oak Grove Drive PasadenaCA91109 United States

ISBN: (纸本)9780877036296

A robotic mission to the Martian moons Phobos and Deimos would offer a wealth of scientific information and serve as a useful precursor to potential human missions. In this paper, we investigate a prospective mission enabled by solar electric propulsion that would explore Phobos via a series of flybys followed by capture into orbit around the moon. Of particular interest are low Adoptions for capture and walkdown to the target science orbits aided by multi-body effects due to the mutual gravitational interaction of Phobos and Mars. We also consider contingency operations in the event of missed thrust or maneuver execution errors.

关键词： Gravitation

来源：评论

学校读者我要写书评

暂无评论

Identification of retrievable asteroids with the tisserand criterion

Identification of retrievable asteroids with the tisserand c...

引用

AIAA/AAS Astrodynamics Specialist Conference 2014

作者： Strange, Nathan Landau, Damon Chodas, Paul Longuski, James Jet Propulsion Laboratory California Institute of Technology 4800 Oak Grove Dr. Pasadena CA 91109 United States School of Aeronautics and Astronautics Purdue University 701 W. Stadium Ave. West Lafayette IN 47907 United States Lunar and Planetary Mission Concepts Group JPL Mission Concepts Section Solar System Dynamics Group JPL Mission Design and Navigation Section

ISBN: (数字)9781624103087

ISBN: (纸本)9781624103087

NASA is currently studying an Asteroid Redirect mission (ARM) concept that could capture an entire 2 to 12 m asteroid or boulder from a larger asteroid and place it in orbit around the Moon. Once at the Moon, astronauts would be sent to visit the asteroid or boulder and use it as a test bed for developing technologies and procedures needed for deep space human missions. In the case of the redirection of an entire asteroid, the asteroid mass could be from 100 to 1000 metric tonnes, and the ARM spacecraft would only be able to apply relatively small ΔV to the asteroid. Therefore, ARM would rely on Lunar Gravity Assists (LGAs) to provide most of the provide most of ΔV needed for capture. This paper presents a method based upon the Tisserand Criterion for identifying asteroids that can be redirected with a small ΔV (

关键词： Asteroids

来源：评论

学校读者我要写书评

暂无评论

Orbit design and control of technology validation mission for refractive space telescope in formation flying

Orbit design and control of technology validation mission fo...

引用

AIAA Guidance, navigation, and Control Conference 2014 - SciTech Forum and Exposition 2014

作者： Park, Sang-Young Calhoun, Philip C. Shah, Neerav Williams, Trevor W. Yonsei University Seoul 120-749 Korea Republic of NASA Goddard Space Flight Center Greenbelt MD 20771 United States Astrodynamics and Control Lab Department of Astronomy Korea Republic of Attitude Control System Engineering Branch MS 591 8800 Greenbelt Rd Greenbelt MD 20771 United States Navigation and Mission Design Branch MS 595 8800 Greenbelt Rd Greenbelt MD 20771 United States

ISBN: (数字)9781624103179

ISBN: (纸本)9781600869624

Many proposed formation flying missions seek to advance the state of the art in spacecraft science imaging by utilizing precision dual spacecraft formation flying to enable a "virtual" telescope (VT). Using precision alignment of two spacecraft very long focal lengths can be achieved by locating the optics on one spacecraft and the detector on the other. Furthermore, orders of magnitude improvement in science imaging over conventional single spacecraft instruments is possible with advances in precision formation flying. Precise astrometric alignment control is required for accurate inertial pointing of the VT. This work presents orbit design and control approaches for VT formation flying, with specific application to the recently proposed Virtual Telescope Demonstration mission (VTDM) using cubesats. The characteristics of the mission orbit are derived from solutions to Hill's equations for the relevant mission orbit. A relative orbit control technique pertaining to the astrometric alignment problem is developed by utilizing the Constrained Model Predictive Control (CMPC) approach. This method enables design of formation flying control laws for a thruster assembly with limited magnitude. Precision formation flying is achieved by use of separate control laws for formation maintenance and precision astrometric alignment. The proposed control scheme compensates for inertial astrometric alignment errors as well as differences in orbital perturbations between the VTDM satellites. Numerical simulations are shown to validate the performance of the proposed relative orbit and alignment control laws for the VTDM. The results satisfy mission requirements and indicate the general applicability of the control algorithm to the VT formation flying architecture. Consequently, the proposed methods of orbit design and control can be applied to inertial astrometric alignment and formation keeping for the many proposed dual spacecraft precision formation flying missions.

关键词： Spacecraft

来源：评论

学校读者我要写书评

暂无评论

Cloud computing for mission design and operations

Cloud computing for mission design and operations

引用

12th International Conference on Space Operations, SpaceOps 2012

作者： Arrieta, Juan Beswick, Robert Gerasimatos, Dimitrios Jet Propulsion Laboratory California Institute of Technology Flight Path Control Section 4800 Oak Grove Drive M/S 230-205 Pasadena CA 91109 United States Jet Propulsion Laboratory California Institute of Technology Navigation and Mission Design System Engineering Section 4800 Oak Grove Drive M/S 301-121 Pasadena CA 91109 United States

The space mission design and operations community already recognizes the value of cloud computing and virtualization. However, natural and valid concerns, like security, privacy, up-time, and vendor lock-in, have prevented a more widespread and expedited adoption into official workflows. In the interest of alleviating these concerns, we propose a series of guidelines for internally deploying a resource-oriented hub of data and algorithms. These guidelines provide a roadmap for implementing an architecture inspired in the cloud com- puting model: associative, elastic, semantical, interconnected, and adaptive. The architec- ture can be summarized as exposing data and algorithms as resource-oriented Web services, coordinated via messaging, and running on virtual machines;it is simple, and based on widely adopted standards, protocols, and tools. The architecture may help reduce com- mon sources of complexity intrinsic to data-driven, collaborative interactions and, most importantly, it may provide the means for teams and agencies to evaluate the cloud com- puting model in their specific context, with minimal infrastructure changes, and before committing to a specific cloud services provider. © 2012 by the American Institute of Aeronautics and Astronautics, Inc.

关键词： Cloud computing

来源：评论

学校读者我要写书评

暂无评论

5-2 Experimental results of time comparison using the time comparison equipment on board ETS-Vill

引用

Journal of the National Institute of Information and Communications Technology 2010年第3-4期57卷 279-288页

作者： Yasuhiro, Takahashi Fumimaru, Nakagawa Ryo, Tabuchi Maho, Nakamura Hiroo, Kunimori Jun, Amagaj Shigeru, Tsuchiya Shin'ichi, Hama Hiroyulci, Noda Space-Time Standards Group New Generation Network Research Center Japan Satellite Communication Satellite Navigation System Japan Time and Frequency Standard Japan Ionosphere Information Engineering Japan Space Communication Group New Generation Wireless Communications Research Center Japan Satellite Laser Ranging Japan Time and Frequency Radio Interferometer Japan Time and Frequency Standard Radio Wave Propagation Japan Quasi-Zenith Satellite Project Team Space Applications Mission Directorate Japan Aerospace Exploration Agency Japan Satellite Navigation System Japan

The engineering Test Satellite type Mu (ETS-Mil) was a geo-synchronous satellite launched on December, 2006. Using ETS-VIR, mobile telecommunications experiment using the large deployable antennas is executed. ETS-VIlI is first satellite in Japan bearing atomic clocks, and basic experiments of satellite positioning are carried out. In National Institute of Information and Communications Technology (NICT), highly precise time and frequency comparison experiment between the satellite and the ground is executed for the first time in the world. Highly precise time comparison experiment between ground stations using an on-board bent-pipe function and ranging experiment are also executed.

关键词： Tracking (position)

来源：评论

学校读者我要写书评

暂无评论

navigation challenges of a kinetic energy asteroid deflection spacecraft

Navigation challenges of a kinetic energy asteroid deflectio...

引用

作者： Bhaskaran, Shyam Chesley, Stephen Park, Ryan Petropoulos, Anastassios Sims, Jon Yeomans, Donald Haw, Robert Jet Propulsion Laboratory California Institute of Technology Pasadena CA 91109 United States Outer Planet Navigation Group Guidance Navigation and Control Section MS 301-276 United States Guidance Navigation and Control Section MS 301-150 United States Guidance Navigation and Control Section MS 301-276 United States Guidance Navigation and Control Section MS 301-140L United States Outer Planet Mission Design Group Guidance Navigation and Control Section MS 301-140L United States Solar System Dynamics Group Guidance Navigation and Control Section MS 301-150 United States

ISBN: (纸本)9781563479458

A simple asteroid deflection experiment can be conducted by a small and inexpensive impactor spacecraft in cooperation with an independent asteroid rendezvous mission. The rendezvous mission would arrive at a near-Earth asteroid in advance of the impactor in order to characterize the asteroid while the impactor makes its way to the target. Then the rendezvous spacecraft would be in position to record the impact event, as well as to measure the deflection imparted as a result of the collision. This paper describes the mission concept and addresses the navigational challenges in delivering the impactor, as well as measuring the resultant deflection. Copyright © 2008 by the American Institute of Aeronautics and Astronautics, Inc.

关键词： Kinetics

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：