公开(公告)号：US06356815B1

公开(公告)日：2002-03-12

申请号：US09648501

申请日：2000-08-25

申请人： Yeong-Wei A. Wu ,  Rongsheng Li ,  Yong Liu

发明人： Yeong-Wei A. Wu ,  Rongsheng Li ,  Yong Liu

IPC分类号： G01C2102

CPC分类号： B64G1/361 ,  G01C21/025 ,  G01S3/7867 ,  G01S5/163 ,  G05D1/0883

摘要： Stellar attitude-control systems and methods are provided with enhanced accuracy because they recognize that important star tracker errors exhibit a boresight symmetry and that these errors can be accurately defined by weighting a measurement-noise covariance matrix R(tn) with variances that are functions of off-boresight angles of detected stars. A method of the invention derives off-boresight angles &thgr; from star-tracker signals of detected stars. These off-boresight angles &thgr; are combined with variance coefficients &agr; to generate off-boresight variances rob(tn) that are functions of the off-boresight angles &thgr; and, in particular, correspond to star tracker color shift errors. A gain matrix K(tn) is then calculated with a weighted measurement-noise covariance matrix R(tn) that includes the off-boresight variances rob(tn). This gain matrix is used to generate an attitude estimate matrix X*(tn) for use in spacecraft attitude control. The variance coefficients &agr; are preferably modified to include star tracker focal length shift errors which are also a function of off-boresight angles &thgr;. It is noted that the variance coefficients &agr; can be reduced by identifying the spectral classes of detected and identified stars. The invention recognizes that Other star tracker errors that are not functions of off-boresight angles are modeled with appropriate constant variances rc(tn) that are used to modify the covariance matrix R(tn).

摘要翻译： 提供恒星姿态控制系统和方法具有更高的精度，因为它们认识到重要的星形跟踪器误差表现出视轴对称性，并且可以通过对作为功能的方差加权测量噪声协方差矩阵R（t​​n）来精确地定义这些误差。 检测到的星的偏离视角。 本发明的一种方法从检测到的恒星的星形跟踪信号中导出离视角θ。 这些离开视轴角度θ与方差系数α组合以产生作为离开视角θ的函数的离开视轴方向rob（tn），特别是对应于星形跟踪器颜色偏移误差。 然后使用包括偏离视差方差rob（tn）的加权测量 - 噪声协方差矩阵R（t​​n）来计算增益矩阵K（tn）。 该增益矩阵用于生成用于航天器姿态控制的姿态估计矩阵X *（tn）。 方差系数α优选地被修改为包括也是偏离视角θ的函数的星形跟踪器焦距偏移误差。 应注意，可以通过识别检测到和识别的星的光谱类别来减小方差系数α。 本发明认识到，不是非视距角函数的其他星形跟踪器误差是用用于修改协方差矩阵R（t​​n）的适当常数变量rc（tn）进行建模的。

公开(公告)号：US06362464B1

公开(公告)日：2002-03-26

申请号：US09504543

申请日：2000-02-15

申请人： Yong Liu ,  Yeong-Wei A. Wu ,  Rongsheng Li ,  Christopher L. Rice

发明人： Yong Liu ,  Yeong-Wei A. Wu ,  Rongsheng Li ,  Christopher L. Rice

IPC分类号： G01C2102

CPC分类号： B64G1/361 ,  G01C21/025 ,  G01S3/7867 ,  G05D1/0883

摘要： An apparatus for determining stellar inertial attitude based upon a plurality of stars includes a star tracker and a controller. The star tracker is used to sense the positions of stars and generate signals corresponding to the positions of the stars as seen in its field of view. The controller checks a star catalog and actively determines which stars to track. The controller does this determination in terms of each star's relative geometry. The controller then commands the star tracker to track these stars and uses them to determine the spacecraft attitude.

摘要翻译： 一种用于根据多个恒星确定恒星惯性姿态的装置包括星形跟踪器和控制器。 星形跟踪器用于感测恒星的位置，并产生与其视场中所见的恒星位置相对应的信号。 控制器检查星号目录，并主动确定要跟踪的星星。 控制器根据每颗星的相对几何来做出这一决定。 然后，控制器命令星形跟踪器跟踪这些恒星并使用它们来确定航天器的姿态。

公开(公告)号：US07487016B2

公开(公告)日：2009-02-03

申请号：US11221646

申请日：2005-09-07

申请人： Richard A. Fowell ,  Rongsheng Li ,  Yeong-Wei A. Wu

发明人： Richard A. Fowell ,  Rongsheng Li ,  Yeong-Wei A. Wu

IPC分类号： B64G1/24

CPC分类号： B64G1/36 ,  G05D1/0883

摘要： A method for controlling an actuator of a vehicle comprises providing a dynamic condition sensor generating a vehicle movement signal and a position sensor for generating a reported position. A processor is coupled to the inertial sensor and the position sensor and comprises an estimator, a position measurement predictor having a filter, a comparator and a control shaping block, said estimator generating a vehicle position based upon the dynamic condition sensor, said position measurement predictor generating an estimated position measurement in response to the reported vehicle position and a matched frequency response to the movement signal, said control shaping block generating an actuator control signal in response to a comparison of the estimated position measurement and the reported vehicle position.

摘要翻译： 一种用于控制车辆的致动器的方法包括提供产生车辆运动信号的动态条件传感器和用于产生报告位置的位置传感器。 处理器耦合到惯性传感器和位置传感器，并且包括估计器，具有滤波器的位置测量预测器，比较器和控制整形块，所述估计器基于动态条件传感器产生车辆位置，所述位置测量预测器 响应于所报告的车辆位置和对所述移动信号的匹配的频率响应来产生估计位置测量，所述控制整形块响应于所估计的位置测量和报告的车辆位置的比较而产生致动器控制信号。

公开(公告)号：US06825806B2

公开(公告)日：2004-11-30

申请号：US10162465

申请日：2002-06-03

申请人： Ketao Liu ,  Richard Fowell ,  Yeong-Wei A. Wu ,  Rongsheng Li

发明人： Ketao Liu ,  Richard Fowell ,  Yeong-Wei A. Wu ,  Rongsheng Li

IPC分类号： H01Q300

CPC分类号： H01Q3/005

摘要： Methods and structures are provided for reducing pointing errors &zgr; of satellite antennas and for generating broad field-of-view satellite attitude acquisition patterns. In one method embodiment, satellite transmit beams have estimated pointing attitudes &bgr; and are transmitted to overlap on a ground-based receiving terminal which has a known terminal location &lgr; and which measures received signal strengths &agr;. Pointing errors &zgr; of the transmit beams are then determined from the estimated pointing attitudes &bgr;, the terminal location &lgr; and the signal strengths &agr; and the pointing errors &zgr; are subsequently reduced by revising the pointing attitudes &bgr;. Other method embodiments utilize known signal-strength functions and antenna signals with known signal parameters such as frequencies and/or modulations.

摘要翻译： 提供了用于减少卫星天线的指向误差zeta和产生广泛的视野卫星姿态采集模式的方法和结构。 在一个方法实施例中，卫星发射波束具有估计的指向姿态β，并且在具有已知终端位置λ并且测量接收信号强度α的基于地面的接收终端上被发送以重叠。 然后从估计的指向态度β确定发射波束的指向误差zeta，随后通过修正指向态度β来减少终端位置λ和信号强度α和指向误差zeta。 其他方法实施例利用具有已知信号参数（例如频率和/或调制）的已知信号强度函数和天线信号。

公开(公告)号：US06681159B2

公开(公告)日：2004-01-20

申请号：US10039488

申请日：2001-10-28

申请人： Rongsheng Li ,  Jeffrey A. Kurland ,  Alec M. Dawson ,  Yeong-Wei A. Wu ,  David S. Uetrecht

发明人： Rongsheng Li ,  Jeffrey A. Kurland ,  Alec M. Dawson ,  Yeong-Wei A. Wu ,  David S. Uetrecht

IPC分类号： B64L100

CPC分类号： G05D1/0883 ,  B64G1/26 ,  B64G1/28 ,  B64G1/285 ,  B64G1/288 ,  B64G1/32 ,  B64G1/36 ,  G05B13/024

摘要： Methods and structures are provided that enhance attitude control during gyroscope substitutions by insuring that a spacecraft's attitude control system does not drive its absolute-attitude sensors out of their capture ranges. In a method embodiment, an operational process-noise covariance Q of a Kalman filter is temporarily replaced with a substantially greater interim process-noise covariance Q. This replacement increases the weight given to the most recent attitude measurements and hastens the reduction of attitude errors and gyroscope bias errors. The error effect of the substituted gyroscopes is reduced and the absolute-attitude sensors are not driven out of their capture range. In another method embodiment, this replacement is preceded by the temporary replacement of an operational measurement-noise variance R with a substantially larger interim measurement-noise variance R to reduce transients during the gyroscope substitutions.

摘要翻译： 提供了通过确保航天器的姿态控制系统不将其绝对姿态传感器驱动到其捕获范围之外来增强陀螺仪替换期间的姿态控制的方法和结构。 在方法实施例中，卡尔曼滤波器的操作过程 - 噪声协方差Q被临时过程噪声协方差Q临时替换。该替换增加了给予最近姿态测量的重量并加速了姿态误差的降低，并且 陀螺偏置误差。 取代陀螺仪的误差效应降低，绝对姿态传感器不会被驱赶出其捕获范围。 在另一方法实施例中，该替换之前是临时替换具有相当大的临时测量噪声方差R的操作测量噪声方差R，以减少在陀螺仪替换期间的瞬变。

公开(公告)号：US06470270B1

公开(公告)日：2002-10-22

申请号：US09708132

申请日：2000-11-07

申请人： David D. Needelman ,  Yeong-Wei A. Wu ,  Rongsheng Li ,  William L. Burkett, Jr.

发明人： David D. Needelman ,  Yeong-Wei A. Wu ,  Rongsheng Li ,  William L. Burkett, Jr.

IPC分类号： G01C2124

CPC分类号： G01C21/025 ,  B64G1/26 ,  B64G1/285 ,  B64G1/288 ,  B64G1/32 ,  B64G1/361 ,  B64G1/363 ,  B64G1/366 ,  B64G1/42 ,  G01S5/163 ,  G05D1/0883

摘要： A method, apparatus, article of manufacture for determining the attitude of a spacecraft having at least one star sensor. The method comprises the steps of selecting a first reference star sensor from among the star sensors; designating two stars observed by the first reference star sensor as a primary star pair; identifying a candidate star pair corresponding to the primary star pair, wherein the candidate star pair is selected from a star catalog having a plurality of entries; estimating an inertial orientation of the first star sensor at least in part from the identified candidate star pair; and determining the spacecraft attitude from the estimated inertial orientation of a reference star sensor selected from a group comprising the first star sensor.

摘要翻译： 一种用于确定具有至少一颗恒星传感器的航天器姿态的方法，装置，制品。 该方法包括从星形传感器中选择第一参考星传感器的步骤; 将由第一参考星传感器观测到的两颗星指定为主星对; 识别对应于所述主星对的候选星对，其中所述候选星对选自具有多个条目的星目录; 至少部分地从所识别的候选星对估计第一星形传感器的惯性取向; 以及根据从包括第一星型传感器的组中选择的参考星形传感器的估计惯性方向确定航天器姿态。

公开(公告)号：US08019544B2

公开(公告)日：2011-09-13

申请号：US11028094

申请日：2005-01-03

申请人： David D. Needelman ,  Rongsheng Li ,  Yeong-Wei A. Wu

发明人： David D. Needelman ,  Rongsheng Li ,  Yeong-Wei A. Wu

IPC分类号： G01C21/00

CPC分类号： B64G1/361 ,  G01C21/025 ,  G01S3/7867

摘要： A method of estimating the alignment of a star sensor (20) for a vehicle (12) includes generating star tracker data. A vehicle attitude and a star sensor attitude are determined in response to the star tracker data. A current alignment sample is generated in response to the vehicle attitude and the star sensor attitude. A current refined estimate alignment signal is generated in response to the current alignment sample and a previously refined estimate alignment signal via a vehicle on-board filter (38).

摘要翻译： 估计用于车辆（12）的星形传感器（20）的对准的方法包括产生星形跟踪器数据。 响应于星形跟踪器数据确定车辆姿态和星形传感器姿态。 响应于车辆姿态和星形传感器姿态产生当前的对准样品。 响应于当前对准样本和经由车载过滤器（38）的先前精确的估计对准信号，产生当前精细估计对准信号。

公开(公告)号：US07228231B2

公开(公告)日：2007-06-05

申请号：US10709348

申请日：2004-04-29

申请人： David D. Needelman ,  Richard A. Fowell ,  Peter C. Lai ,  Yeong-Wei A. Wu ,  Rongsheng Li

发明人： David D. Needelman ,  Richard A. Fowell ,  Peter C. Lai ,  Yeong-Wei A. Wu ,  Rongsheng Li

IPC分类号： G01C21/00 ,  B64G1/10

CPC分类号： G01C3/08 ,  B64G1/361 ,  G01C22/00

摘要： A vehicle (12) including a control system (18) is used for controlling vehicle attitude or angular velocity (38). The processor (24) is coupled to a star sensor or tracker (22) and a memory (30) that may include a star catalog (32), and an exclusion list (36). The exclusion list (36), a list of stars to be temporarily excluded from consideration when determining attitude or angular velocity or relative alignment of star sensors or trackers, is calculated on board. Such a calculation prevents the necessity for a costly, periodic, ground calculation and upload of such data. By manipulating the star catalog, or sub-catalogs derived from said catalog, based upon the exclusion list (36), measurements of such excluded stars are prevented from corrupting the attitude or angular velocity or alignment estimates formulated on board. The system uses multiple stayout zones for excluding stars from the exclusion list. A central exclusion zone excludes all stars while a second or more exclusion zones allow some stars to be used in the attitude determination

摘要翻译： 包括控制系统（18）的车辆（12）用于控制车辆姿态或角速度（38）。 处理器（24）耦合到星形传感器或跟踪器（22）和可包括星形目录（32）的存储器（30）和排除列表（36）。 排除列表（36）在船上计算确定姿态或角速度或星形传感器或跟踪器的相对对齐时暂时排除考虑的星星列表。 这样的计算可以防止对这些数据进行昂贵，周期性，地面计算和上传的必要性。 通过根据排除列表（36）操纵从所述目录导出的星号目录或子目录，防止这些排除的星星的测量破坏了在船上制定的姿态或角速度或对准估计。 系统使用多个停留区域来排除排除列表中的星星。 中央排除区不包括所有星星，而第二个或更多个禁区可允许在姿态确定中使用一些恒星

公开(公告)号：US06766227B2

公开(公告)日：2004-07-20

申请号：US10300454

申请日：2002-11-19

申请人： David D. Needelman ,  Yeong-Wei A. Wu ,  Rongsheng Li

发明人： David D. Needelman ,  Yeong-Wei A. Wu ,  Rongsheng Li

IPC分类号： G05D100

CPC分类号： G01C21/025 ,  B64G1/26 ,  B64G1/285 ,  B64G1/288 ,  B64G1/361 ,  G05D1/0883

摘要： Attitude acquisition methods and systems are provided which reduce the time generally required to acquire spacecraft attitude estimates and enhance the probability of realizing such estimates. The methods and systems receive, over a time span &Dgr;t, successive frames of star-sensor signals that correspond to successive stellar fields-of-view, estimate spacecraft rotation &Dgr;r throughout at least a portion of the time span &Dgr;t, and, in response to the spacecraft rotation &Dgr;r, process the star-sensor signals into a processed set of star-sensor signals that denote star positions across an expanded field-of-view that exceeds any of the successive fields-of-view. The expanded field-of-view facilitates identification of the stars that generated the processed set of star-sensor signals to thereby acquire an initial attitude estimate.

摘要翻译： 提供了姿态获取方法和系统，减少了获取航天器态度估计所需的时间，并提高了实现此类估计的可能性。 方法和系统在时间跨度Deltat中接收对应于连续的恒星视场的星形传感器信号的连续帧，在至少一部分时间段Deltat中估计航天器旋转Deltar，并响应于 航天器旋转Deltar，将星形传感器信号处理成一组经过处理的恒星传感器信号，它们表示超过任何连续视场的扩展视场中的星形位置。 扩展的视野有助于识别产生经处理的星形传感器信号集合的恒星，从而获得初始姿态估计。

公开(公告)号：US06289268B1

公开(公告)日：2001-09-11

申请号：US09516854

申请日：2000-03-02

申请人： Garry Didinsky ,  Arunkumar P. Nayak ,  Rongsheng Li ,  Yeong-Wei A. Wu ,  Jeffrey A. Kurland ,  David D. Needelman

发明人： Garry Didinsky ,  Arunkumar P. Nayak ,  Rongsheng Li ,  Yeong-Wei A. Wu ,  Jeffrey A. Kurland ,  David D. Needelman

IPC分类号： G06F700

CPC分类号： G05D1/0883

摘要： A star tracker coupled to the spacecraft having a star catalog associated therewith. A sun sensor is coupled to the spacecraft. A control processor is coupled to the star tracker and the sun sensor. The processor obtains star data using a star tracker and an on-board star catalog. The processor generates a coarse attitude of the spacecraft as a function of the star data, and establishes a track on at least one star in the on-board star catalog. The processor calculates a sun tracking rate, and obtains a normal phase attitude as a function of the star data and the coarse attitude. The information is used to slew the spacecraft to a desired attitude.

摘要翻译： 耦合到具有与之相关联的星形目录的航天器的星形跟踪器。 太阳传感器耦合到航天器。 控制处理器耦合到星形跟踪器和太阳传感器。 处理器使用星形跟踪器和板载星形目录获取星形数据。 处理器根据星型数据产生航​​天器的粗略姿态，并在车载星形目录中的至少一颗恒星上建立轨道。 处理器计算太阳跟踪率，并且作为星数据和粗略姿态的函数获得正常相位姿态。 该信息用于将飞船旋转到所需的姿态。