Class / Patent application number | Description | Number of patent applications / Date published |
701013000 | Spacecraft or satellite | 42 |
20080228332 | ACTIVE CONTROL OF SOFT HYBRID ISOLATION SYSTEMS - Apparatus, Systems, and Methods are provided for controlling motion of a spacecraft. One apparatus includes a non-contacting actuator and a passive mechanical system coupled in parallel with one another. A system includes a payload, a bus, and a hybrid actuator including a non-contacting actuator and a passive mechanical system coupled in parallel, and coupled between the bus and the payload. The system also includes an inertial actuator configured to maneuver the bus to maintain a relative position and/or attitude of the bus with respect to the payload. One method includes receiving a signal instructing a first controller to change the position and/or attitude of a payload and utilizing a hybrid system to change the position and/or attitude of the payload. The method also includes receiving the signal at a second controller and utilizing a system to change a position and/or attitude of the bus independent of the payload. | 09-18-2008 |
20080249673 | System and method for controlling satellite based on integrated satellite operation data - Provided is a satellite control system based on integrated satellite operation data and a method thereof. The satellite control system includes: a satellite operation data schema editing means for creating a document type definition file and defining a schema; a mission planning means for creating a mission timeline and recording the mission timeline; a command planning means for converting a task into telecommands and recording the telecommand; a command preparing means for creating a telecommand procedure and recording the telecommand procedure; a command transmitting means for creating a telecommand code, transmitting the telecommand code to a satellite and recording the telecommand code; a command verifying means for receiving telemetry data and recording a telecommand verification result; and a performance result reporting means for creating a mission performance result and recording the mission performance result. | 10-09-2008 |
20080269965 | CALIBRATION OF SHIP ATTITUDE REFERENCE - A ship includes a star tracker mounted on a platform stabilized in ENU by the inertial navigation system (INS). The line-of-sight (LOS) of the star tracker is directed toward two separated stars, and the LOS difference angles are noted. The angles are processed to generate vector triads representing geodetic (ephemeris) and navigation system attitude. The triads are processed to generate a coordinate transformation matrix. The transformation matrix is separated into systematic error and reference attitude error. The reference attitude error is summed with the inertial navigation system attitude to generate corrected ENU attitude. The corrected attitude is used as a reference for shipboard sensors, to reduce errors when the sensor data is linked to other platforms. | 10-30-2008 |
20080275598 | Trajectory Estimation System for an Orbiting Satellite - In one embodiment of the disclosure, a computing system includes a processor and a computer readable medium. The computer readable medium is operable to, when executed on the processor, determine an estimated trajectory of a satellite using a sequential mode of operation, perform a thruster burn, receive a data point from an uplink/downlink facility, determine an estimated trajectory and an estimated thruster performance of the satellite based upon the received data point. If the trajectory error is above a specified threshold level, repeat receiving an updated data point from the uplink/downlink facility, determining an updated estimated trajectory and an updated estimated thruster performance of the satellite based upon the updated data point, and determining an updated trajectory error based upon the updated data point. | 11-06-2008 |
20090012662 | Method and apparatus for determining a satellite attitude using crosslink reference signals - A method and apparatus for determining the attitude of a satellite using crosslink information is disclosed. The method and apparatus integrates data from the crosslinks with data available from other sources including, for example, star sensors, inertial sensors, and earth limb sensors to derive an accurate estimate of the satellite attitude, even in harsh nuclear environments. | 01-08-2009 |
20090132105 | Proximity Spacecraft Maneuvering - Provided is a method and system for maneuvering a first spacecraft relative to a nearby second spacecraft that occupies a finite volume of space including obstacles in the vicinity of the second from a measured present relative position to a desired ending relative position. A trajectory is computed for the first spacecraft from the present relative position to the ending relative position using the A* algorithm. One or more thrusters of the first spacecraft are then fired. The first spacecraft's relative position and velocity are then measured and compared to the computed trajectory. | 05-21-2009 |
20090222152 | DEVICE FOR CONTROL OF RELATIVE POSITION(S) BY MEASUREMENTS OF POWER, FOR A SPACECRAFT OF A GROUP OF SPACECRAFT IN FORMATION - A control device (D) for a spacecraft of a group of spacecraft intended to travel in a chosen formation comprises i) a set of at least three send/receive antennas (A | 09-03-2009 |
20090222153 | METHOD OF DETERMINING AND CONTROLLING THE INERTIAL ATTITUDE OF A SPINNING, ARTIFICIAL SATELLITE AND SYSTEMS THEREFOR - A method of and apparatus for determining and controlling the inertial attitude of a spinning artificial satellite without using a suite of inertial gyroscopes. The method and apparatus operate by tracking three astronomical objects near the Earth's ecliptic pole and the satellite's and/or star tracker's spin axis and processing the track information. The method and apparatus include steps and means for selecting preferably three astronomical objects using a histogram method and determining a square of a first radius (R | 09-03-2009 |
20090299553 | Satellite Control - A satellite has a depletion detector arranged in a propellant line such that, when depletion is detected, the amount of propellant remaining in the propellant lines is sufficient to dispose of the satellite, and may include a margin sufficient for 6-12 months of stationkeeping. This provides a simple and reliable method of determining when decommissioning is required. | 12-03-2009 |
20100023188 | SINGULARITY ESCAPE AND AVOIDANCE USING A VIRTUAL ARRAY ROTATION - Techniques for providing singularity escape and avoidance are disclosed. In one embodiment, a method for providing control moment gyroscope (CMG) attitude control singularity escape includes calculating a Jacobian A of a set of control equations, calculating a measure of closeness to a singularity, and comparing the calculated closeness to a threshold value, when the calculated closeness is less than or equal to the threshold value, recalculating the Jacobian A. Recalculating may include determining a new direction of virtual misalignment of β and γ, recalculating the Jacobian inputting the new direction of the virtual misalignment, recalculating the measure of closeness to a singularity, and comparing the measure of closeness to the threshold value. Further, the method may include calculating a gimbal rate command if the of closeness is greater than the threshold value and generating a torque from the gimbal rate command to control the attitude of a satellite. | 01-28-2010 |
20100042274 | ATTITUDE CONTROL METHOD USING TARGET TRACK APPROXIMATION - Provided is a method for controlling an attitude of a satellite using target track approximation. The method includes the steps of: a) receiving coordinate information of at least one of target areas; b) generating a target track by approximating a track of a satellite based on the received coordinate information; and c) detecting a location of the satellite on a current track, calculating an attitude angle of the satellite for the target track using the location of the satellite and the location of the target area, and applying the calculated attitude angle of the satellite to control the attitude of the satellite. | 02-18-2010 |
20100049381 | System and Method for Simultaneously Processing Telemetry Data - According to one embodiment of the disclosure, a method for use in telemetry processing includes receiving telemetry data originating from a satellite, such that the telemetry data comprises a plurality of data segments. The method includes processing the plurality of data segments simultaneously and transmitting a signal to the satellite, in response to the processing, for effecting a change in the direction of the satellite. | 02-25-2010 |
20100063653 | SINGULARITY ESCAPE AND AVOIDANCE USING A VIRTUAL ARRAY ROTATION - Techniques for providing singularity escape and avoidance are disclosed. In one embodiment, a method for providing control moment gyroscope (CMG) attitude control singularity escape includes calculating a Jacobian A of a set of control equations, calculating a measure of closeness to a singularity, and comparing the calculated closeness to a threshold value, when the calculated closeness is less than or equal to the threshold value, recalculating the Jacobian A. Recalculating may include determining a new direction of virtual misalignment of β and γ, recalculating the Jacobian inputting the new direction of the virtual misalignment, recalculating the measure of closeness to a singularity, and comparing the measure of closeness to the threshold value. Further, the method may include calculating a gimbal rate command if the of closeness is greater than the threshold value and generating a torque from the gimbal rate command to control the attitude of a satellite. | 03-11-2010 |
20100168938 | METHOD FOR IMPROVING MANEUVERABILITY AND CONTROLLABILITY BY SIMULTANEOUSLY APPLYING BOTH REACTION WHEEL-BASED ATTITUDE CONTROLLER AND THRUSTER-BASED ATTITUDE CONTROLLER - Provided are an attitude control system and method of a spacecraft of an artificial satellite that may enhance a maneuverability and a controllability by simultaneously applying a reaction wheel and a thruster among drive units used to maneuver an attitude of the spacecraft of the artificial satellite. The attitude control system may include: a thruster-based attitude controller which control firing time of thrusters mounted on the spacecraft; and a reaction wheel-based attitude controller controlling driving of a reaction wheel mounted on the spacecraft. The spacecraft may include a plurality of reaction wheels. When a defect occurs in the spacecraft due to a partial malfunction of the reaction wheels, an attitude maneuverability of the spacecraft may be corrected by simultaneously applying the thruster-based attitude controller and the reaction wheel-based attitude controller. | 07-01-2010 |
20100179711 | SPACECRAFT PAYLOAD ORIENTATION STEERING - Spacecraft payload orientation steering is provided for an orbiting spacecraft in motion along an orbit track around a celestial body, the orbit track having a nominal inclination with respect to an equatorial orbit, a substantial eccentricity, and a drift angle with respect to the nominal inclination. Coordinates of an optimal payload target location as a function of a spacecraft position along the orbit track are determined, the target location being on the surface of the celestial body and having a substantial motion with respect to the surface and with respect to a spacecraft nadir. A payload of the spacecraft is substantially aligned with the determined coordinates by steering the satellite body to correct for at least one of the inclination drift angle, and the eccentricity, thereby adjusting the spacecraft orientation as a function of the spacecraft position along the orbit track. | 07-15-2010 |
20100228407 | METHOD OF DETERMINING AND CONTROLLING THE INERTIAL ATTITUDE OF A SPINNING, ARTIFICIAL SATELLITE AND SYSTEMS THEREFOR - A method of and apparatus for determining and controlling the inertial attitude of a spinning artificial satellite without using a suite of inertial gyroscopes. The method and apparatus operate by tracking three astronomical objects near the Earth's ecliptic pole and the satellite's and/or star tracker's spin axis and processing the track information. The method and apparatus include steps and means for selecting preferably three astronomical objects using a histogram method and determining a square of a first radius (R | 09-09-2010 |
20110010027 | SYSTEMS AND METHODS FOR ATTITUDE PROPAGATION FOR A SLEWING ANGULAR RATE VECTOR - Computer-based systems and methods for determining attitude of a moveable object. Attitude is determined by a transformation matrix {right arrow over (U)} from a body coordinate frame of the moveable object to an inertial reference frame. The transformation matrix is determined by: (i) determining a slew rate vector, {right arrow over (α)}, for time t | 01-13-2011 |
20110144835 | SYSTEM AND METHODS FOR SIMULTANEOUS MOMENTUM DUMPING AND ORBIT CONTROL - The present system and methods enable simultaneous momentum dumping and orbit control of a spacecraft, such as a geostationary satellite. Control equations according to the present system and methods generate accurate station-keeping commands quickly and efficiently, reducing the number of maneuvers needed to maintain station and allowing station-keeping maneuvers to be performed with a single burn. Additional benefits include increased efficiency in propellant usage, and extension of the satellite's lifespan. The present system and methods also enable tighter orbit control, reduction in transients and number of station-keeping thrusters aboard the satellite. The present methods also eliminate the need for the thrusters to point through the center of mass of the satellite, which in turn reduces the need for dedicated station-keeping thrusters. The present methods also facilitate completely autonomous orbit control and control using Attitude Control Systems (ACS). | 06-16-2011 |
20110153122 | ON-LINE INERTIA ESTIMATION FOR USE IN CONTROLLING AN AEROSPACE VEHICLE - A system for controlling an aerospace vehicle using on-line inertia estimation may include an attitude sensor to measure an attitude of the aerospace vehicle. The system may also include a processor on board the aerospace vehicle. An inertia estimator operable on the processor may generate an on-line inertia estimate of the aerospace vehicle. A rate and attitude estimator operable on the processor may determine an angular position and angular velocity of the aerospace vehicle using the attitude measurement of the aerospace vehicle and the on-line inertia estimate for controlling movement and orientation of the aerospace vehicle without any rates of rotation of the aerospace vehicle being required. | 06-23-2011 |
20110153123 | ALGORITHM FOR SIMULTANEOUS ATTITUDE MANEUVER AND MOMENTUM DUMPING - A system and method are disclosed for simultaneous attitude maneuver and momentum dumping. The attitude maneuver is performed using nominal wheel control to minimize propellant usage, while applying a momentum management command to the thruster control loop in order for the wheels to accomplish the desired spacecraft maneuver while simultaneously being reset to a de-saturated target state. The system and method involve a wheel system comprised of reaction wheels and/or a control moment gyroscope (CMG), at least one thruster, and control logic that is in communication with the wheel system and thruster(s). If a spacecraft maneuver is in progress, the control logic biases an error input signal to a thruster control loop to track the wheel maneuver to prevent unnecessary propellant consumption. The control logic is further operable to output thruster torque commands and wheel torque commands that accomplish the maneuver while achieving the desired final momentum target. | 06-23-2011 |
20110160939 | DEVICE FOR CONTROLLING RELATIVE POSITION (S) BY ANALYZING DUAL-FREQUENCY SIGNALS, FOR A SPACECRAFT OF A GROUP OF SPACECRAFT IN FORMATION - A control device (D), for a spacecraft (S | 06-30-2011 |
20110196550 | Method and apparatus for initial orbit determination using high-precision orbit propagation and maneuver modeling - A method of determining an orbit of an orbital object includes computing predicted tracking measurement values based on the orbit computed from the initial conditions factoring in any modeled environmental forces and realistic maneuvers; computing the differences between the actual and predicted tracking measurements; determining an improved estimate of the initial conditions that reduces the measurement errors using a minimization or root finding algorithm; after the algorithm has converged, reviewing the hypothetical maneuvers in the force model, taking each value and determining which values came up as near-zero in the minimized solutions and which values came up as those of measurable thrust; determining overall burn duration using the first and last burn times; determining the thrust profile of the orbital object over the observation period using the integrated thrust values; and determining the actual maneuver based on the observation data. | 08-11-2011 |
20120016541 | System and Method for Assessing the Risk of Conjunction of a Rocket Body with Orbiting and Non-Orbiting Platforms - A system and method for assessing the risk of conjunction of a rocket body with orbiting and non-orbiting platforms. Two-body orbital dynamics are used to initially determine the kinematic access for a ballistic vehicle. The access may be represented in two ways: as a volume relative to its launcher and also as a geographical footprint relative to a target position that encompasses all possible launcher locations. | 01-19-2012 |
20120022726 | Method for Maintaining Pose of Spacecraft - Embodiments of invention disclose a system and a method for formation-keeping of a spacecraft in response to a displacement of the spacecraft to a displaced pose with respect to at least one direction of the displacement, wherein the spacecraft is configured to issue a compensative force by generating a command to issue a compensative force. The compensative force is determined as a function of a sum of the base force configured for maintaining the spacecraft in the displaced pose with respect to the direction of the displacement and an excess force configured for optimizing the formation-keeping with respect to the direction of the displacement of the spacecraft at the displaced pose. | 01-26-2012 |
20120179308 | Method and System for High Fidelity VTOL and Hover Capability - A vehicle having a plurality of thruster components, wherein each of the thruster components includes a plurality of sub-thrusters, each sub-thruster being grouped into one of a plurality of control groups. The vehicle including a control system receiving information related to the vehicle, wherein the control system selects one of the control groups and activates the sub-thrusters of the selected control group. | 07-12-2012 |
20120209457 | Aircraft Traffic Separation System - A method and apparatus for managing separation between vehicles. A closest point of approach between a first vehicle traveling along a first path and a second vehicle traveling along a second path is predicted. A number of compensation commands for altering the first path of the first vehicle are generated using the closest point of approach and a desired level of separation between the first vehicle and the second vehicle. The number of compensation commands is integrated with a number of control commands for the first vehicle to form a final number of control commands configured to maneuver the first vehicle to substantially maintain the desired level of separation between the first vehicle and the second vehicle. A response of the first vehicle to the final number of control commands is a desired response. | 08-16-2012 |
20120232724 | REFINING A POSITION ESTIMATE OF A LOW EARTH ORBITING SATELLITE - In a method for refining a position estimate of a low earth orbiting (LEO) satellite a first position estimate of a LEO satellite is obtained with a GNSS receiver on-board the LEO satellite. The first position estimate is communicated to a Virtual Reference Station (VRS) processor. VRS corrections are received at the LEO satellite, the VRS corrections having been calculated for the first position estimate by the VRS processor. The VRS corrections are processed on-board the LEO satellite such that a VRS corrected LEO satellite position estimate of the LEO satellite is generated for the first position estimate. | 09-13-2012 |
20120253563 | Positioning Satellites - A method comprising: receiving first information for defining a first algebraic function that relates a time variable to a first mapped variable; using the function to convert a time variable value to a first value of the first mapped variable e.g. s; converting the first value of the first mapped variable to a second value of a second mapped variable e.g. U; and positioning a satellite by converting the second value of the second mapped variable value to a position value that positions a satellite. | 10-04-2012 |
20120303185 | SPACECRAFT MOMENTUM MANAGEMENT USING SOLAR ARRAY - Stored momentum on a spacecraft is managed by determining a target profile of stored momentum as a function of time for the spacecraft; measuring a difference between a momentum value actually stored on the spacecraft and a desired momentum value, where the desired momentum value substantially conforms to the target profile at a particular time; reducing the difference by producing a torque on the spacecraft, where the torque results from selectively controlling at least one solar array position offset angle, the offset angle being an offset of at least one solar array of the spacecraft from a nominal sun pointing direction. | 11-29-2012 |
20130006449 | Apparatus, system and method for spacecraft navigation using extrasolar planetary systems - The present invention provides an innovative apparatus, system and method for onboard spacecraft location determination and navigation by employing the observation of extrasolar planetary star system motion. In one apparatus embodiment a gas absorption cell is placed between a sensor and the light from a reference star system with at least one exoplanet, such that the sensor can detect the spectrum through the gas absorption cell. Radial velocities can be calculated via Doppler Spectroscopy techniques and incorporated into a spacecraft navigation solution. The present invention can enable and enhance significant mission capabilities for future manned and unmanned space vehicles and missions. | 01-03-2013 |
20130085628 | Modified Kalman Filter for Generation of Attitude Error Corrections - Methods, systems, and computer-readable media are described herein for using a modified Kalman filter to generate attitude error corrections. Attitude measurements are received from primary and secondary attitude sensors of a satellite or other spacecraft. Attitude error correction values for the attitude measurements from the primary attitude sensors are calculated based on the attitude measurements from the secondary attitude sensors using expanded equations derived for a subset of a plurality of block sub-matrices partitioned from the matrices of a Kalman filter, with the remaining of the plurality of block sub-matrices being pre-calculated and programmed into a flight computer of the spacecraft. The propagation of covariance is accomplished via a single step execution of the method irrespective of the secondary attitude sensor measurement period. | 04-04-2013 |
20140032022 | Method For Reducing the Angular Momentum and Controlling the Attitude of a Spacecraft - A method for reducing the angular momentum of a spacecraft comprises a propulsion device able to generate a torque along a Z axis corresponding to an axis of maximum inertia or minimum inertia of the spacecraft, an X axis and a Y axis forming with Z an orthogonal frame; an angular momentum accumulating device, able to generate an angular momentum and a torque along the three axes; and a set of sensors able to measure the angular velocities and estimate the angular momentum of the spacecraft. The method comprises a first step of aligning the angular momentum of the spacecraft along the Z axis, consisting in slaving the angular momentum of the angular momentum accumulating device to the angular velocity of the spacecraft, and a second step of reducing the angular momentum of the spacecraft using a torque generated by the propulsion device. | 01-30-2014 |
20140236401 | Star Tracker Rate Estimation with Kalman Filter Enhancement - An attitude estimator that uses star tracker measurements and enhanced Kalman filtering, with or without attitude data, to provide three-axis rate estimates. The enhanced Kalman filtering comprises taking an average of forward and rearward propagations of the Kalman filter states and the error covariances. The star tracker-based rate estimates can be used to control the attitude of a satellite or to calibrate a sensor, such as a gyroscope. | 08-21-2014 |
20140365043 | Estimation Of Propellant Remaining In A Satellite - An amount of propellant remaining in an orbiting satellite can be estimated in a more accurate manner than is possible with conventional approached. Pressure and temperature telemetry data received from the satellite can be analyzed using a maximum likelihood estimation approach that reconstructs a predicted tank pressure signal using the temperature data and determines a pressurant volume necessary to make the reconstructed pressure signal match the received pressure signal. Drift of the pressure data received from pressure transducers in the satellite can also be addressed using the current subject matter, as can issues including but not limited to inaccessible propellant due to satellite spin, tank expansion under pressure, and the like. Independent determinations of the amounts of propellant remaining can be made using moment of inertia calculations in situations in which an axis of spin of the satellite is known a priori. | 12-11-2014 |
20150120096 | Angles-Only Initial Orbit Determination (IOD) - A methodology for initial orbit determination of an object about an astronomical body searches a grid of possible boundary values on the range-to-object over the observation interval to find the grid point and corresponding initial orbit that best fits all of the three or more (N) angles-only observations according to an error metric. The search is conducted by solving a boundary-value problem (e.g. Lambert's Problem) for different grid points. The state vector is propagated to determine estimated observation directions for the remaining N−2 observations. The grid point (and initial orbit) that best fit all of the observations is selected. The grid may be searched by testing each and every point on the grid or by using other optimization techniques such as hill climbing algorithms to find the optimal grid point. For efficiency, the search may start with a broad but coarse initial grid and increase the resolution of the grid as the search converges to a solution. | 04-30-2015 |
20150149001 | MANEUVER PROCESSING - A computing device may detect that a space object has undergone a maneuver and may attempt to calculate a solution to that maneuver based in part on start and stop times and thrust uncertainties associated with the detected maneuver. However, the computing device may sometimes be unable to calculate an acceptable solution for a detected maneuver given these initial start and stop times and thrust uncertainties. Thus, the various embodiments provide for a computing device and methods implemented by a processor executing on the device for identifying and calculating a recovery maneuver of a space object when an acceptable solution for a detected maneuver cannot be determined. In the various embodiments, a computing device processor may generate a recovery maneuver based on the detected maneuver, and the processor may adjust the start and stop times and the uncertainty values of the recovery maneuver until an acceptable solution is found. | 05-28-2015 |
20150298827 | ATTITUDE DETERMINATION USING INFRARED EARTH HORIZON SENSORS - Described herein are systems and methods for attitude determination using infrared Earth horizon sensors (EHSs) with Gaussian response characteristics. Attitude information is acquired by detecting Earth's infrared electromagnetic radiation and, subsequently, determining the region obscured by Earth in the sensors' fields of view to compute a nadir vector estimation in the spacecraft's body frame. The method can be applied when two sensors, each with known and distinct pointing directions, detect the horizon, which is defined as having their fields of view partially obscured by Earth. The method can be implemented compactly to provide high-accuracy attitude within small spacecraft, such as CubeSat-based satellites. | 10-22-2015 |
20150367966 | ATTITUDE DETERMINATION AND CONTROL SYSTEM (ADCS), SUN SENSOR, AND STAR TRACKER - An ADCS module may be configured to use coordinate data from | 12-24-2015 |
20160046395 | System and Method for Managing Momentum Accumulation - A system for managing momentum accumulation of a spacecraft in orbit may include a reaction wheel assembly for controlling an attitude of a body of a spacecraft, the body defining at least one face, and absorbing momentum, a plurality of arcjet thrusters coupled to the face to generate thrust, and a control processor coupled to the plurality of arcjet thrusters for controlling the thrust, wherein actuation of each arcjet thruster of the plurality of arcjet thrusters is configured to produce a net momentum accumulation in the reaction wheel assembly that is below a momentum saturation point of the reaction wheel assembly. | 02-18-2016 |
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