Abstract: A system may include a storage device that stores a set of instructions and a processor in communication with the storage device. When executing the set of instructions, the processor may be configured to cause the system to obtain, from a user terminal, a first geographical location via a network and obtain a second geographical location associated with a virtual parking region. The first geographical location may be determined by the user terminal according a GPS signal. The virtual parking region may include parking space for vehicles. The processor may also be configured to cause the system to determine whether a distance between the first geographical location and the second geographical location is less than a threshold and obtain information associated with the virtual parking region in response to the determination that the distance is less than the threshold.

Abstract: The use of an accelerometer for inertial navigation of a low thrust spacecraft undergoing acceleration wherein the inaccuracy of the accelerometer is less than the uncertainty in the accuracy of a modeled non-gravitational component of the acceleration that the spacecraft is undergoing is disclosed. A method of navigating a spacecraft having a low thrust propulsion system is also disclosed. The method comprises engaging the low thrust propulsion system, measuring the acceleration of the spacecraft using an accelerometer with an inaccuracy less than the uncertainty in the acceleration imparted by the low thrust propulsion system and acquiring a trajectory estimate using the measured acceleration. The trajectory estimate may be updated using an external reference navigation sensor.

Abstract: Systems and methods are provided for scheduling objects having pair-wise and cumulative constraints. The systems and methods presented can utilize a directed acyclic graph to increase or maximize a utilization function. Violation of cumulative constraints can be identified at the moment of constraint violation such that events resulting in constraint violations can be removed from the schedule while the schedule is being determined. By removing the events triggering constraint violations at the point of constraint violation, the systems and methods provided can determine optimal or near-optimal schedules in a relatively quick and efficient manner compared to systems and methods that check for violations of cumulative constraints after determining a schedule. The objects can comprise satellites in a constellation of satellites.

Abstract: Method and system for predicting collision probability of space objects are provided. Space objects are allocated according to a total number thereof for parallel computation in a GPU device. Initial orbit states of the space objects are generated by an initial-orbit-state generation kernel of the GPU device. Orbit propagation for each space object is performed based on the initial orbit state to predict a state of each space object by an orbit propagation kernel of the GPU device. The predicted states of the space objects are collected by a predicted-orbit-state collection kernel of the GPU device. A real-time visualization and rendering of the predicted space objects are performed in a form of point cloud during interactions between CPU threads and GPU kernels. A CPU host predicts a collision probability of any two space objects among the multitude of space objects, according to the interactions between the CPU threads and the GPU kernels.

Abstract: A layered architecture for customer payload systems is disclosed to provide a scalable, reconfigurable integration platform targeted at multiple unmanned aerial vehicles (UAV), and remove both UAV specific and payload equipment specific characteristics that increase complexity during integration. The layered architecture is a modular design architecture that is split by function. Standard interfaces are implemented between functional layers to increase reconfiguration possibilities and to allow reuse of existing components and layers without modification to the payload or UAV. The standard interfaces also promote easy connection and disconnection from other layer components. Additionally, once the layered architecture is implemented, technological or functional requirements changes can be isolated to one specific component layer, not the entire payload stack.

Abstract: Satellite transfer orbit search methods are described herein. One disclosed example method includes determining, based on boundary transfer orbits of a satellite, end points of an oblate epicycloid segment related to a transfer orbit of the satellite, and calculating, using a processor, a shape of the oblate epicycloid segment based on satellite data and the end points to define a search zone to determine a position of the satellite as the satellite moves along the transfer orbit.

Abstract: A method and apparatus are presented for providing a compact extended ephemeris package for GNSS processing. An extended ephemeris service provides orbit trajectories and clock corrections which are predicted into the future for navigation satellites. The extended ephemeris package format used allows the ephemeris information to be sent quickly and efficiently, even when using a low bandwidth communication network. Client GNSS receiver devices obtain the extended ephemeris package and extract the satellite ephemeris information for later use. This allows a client device to operate for many days or weeks without needing to decode or receive new satellite ephemeris information.

Abstract: A method and system for anti-interference compound on-line guidance in the atmosphere-entering stage of a Mars lander is provided in the present invention.

Abstract: A method is described for avoiding gyroscopic singularities during attitude correction to a system, such as a spacecraft having a CMG array. The method receives a corrective torque vector ? and gimbal angle values ? for each of at least three gimbals within the CMG array. The method generates a Jacobian matrix A as a function of gimbal angle values ?. The method calculates a determinant D of Jacobian matrix A. If the determinant is not equal to zero, it is not singular, and the method calculates a gimbal rate {dot over (?)} using a pseudo-inverse steering law equation. If the determinant is equal to zero, it is singular, and the method calculates a gimbal rate {dot over (?)} using a singularity avoidance steering law equation. The gimbal rate {dot over (?)} is output and can be applied to a CMG array resulting in applied torque to a spacecraft and attitude correction.

Abstract: Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for receiving data related to a first flight risk factor and a second flight risk factor where the first and second risk factors include one of: a proficiency risk factor, an equipment risk factor, an environmental risk factor, or a performance risk factor. Applying a first weighting to the first flight risk factor to generate a first weighted flight risk factor, and applying a second weighting to the second flight risk factor to generate a second weighted flight risk factor. Assessing a flight risk level for a flight based on the first weighted flight risk factor and the second weighted flight risk factor. Providing data indicating the assessed flight risk level for the flight for display to a user.

Abstract: A method and apparatus for reporting almanac versions and almanac identification by a mobile station to a server is provided. The server compares the almanac version and almanac identification held by the mobile station with almanac versions and almanac identifications held by the server. The server then sends instructions to the mobile station to match the server versions of the almanac versions and almanac identifications for the almanac versions and almanac identifications that the mobile station should hold.

Abstract: Device for receiving radio-navigation signals, for aiding the piloting of an aircraft, comprising a first master GNSS module and a second slave GNSS module which are dissimilar, the first master GNSS module comprising a first means for processing radio-navigation signals and a first means for computing guidance data (Xg), the second slave GNSS module comprising a second means for processing radio-navigation signals and a second means for computing guidance data (Xg) on the basis of the measurements provided by the said second means for processing signals, each GNSS module furthermore comprising a comparison means for comparing between the outputs Xg1,Xg2 of the said first and second means for computing guidance data, suitable for executing the following integrity test: |Xg1?Xg2|>Kg·?{square root over (Variance(Xg1?Xg2))} and for inferring an integrity defect if the said integrity test is satisfied.

Abstract: A propulsion system for the orbital control of a satellite with terrestrial orbit travelling with a speed of displacement along an axis V tangential to the orbit comprises two propulsion assemblies, fixed to the satellite facing one another with respect to the plane of the orbit, each of the propulsion assemblies comprising two propulsion modules; each of the propulsion modules successively comprising: a motorized link for rotation about an axis parallel to the axis V, an offset arm, and a platen supporting a propulsion unit able to deliver a thrust oriented along an axis perpendicular to the axis V; the two propulsion modules of each propulsion assembly being linked to the satellite on either side and substantially at equal distances from a plane perpendicular to the axis V passing through a centre of mass of the satellite.

Abstract: A control apparatus for an earth-distant-platform includes a control unit, which includes with a control input and a control output, and a memory element. The memory element contains a plurality of operating value parameter sets for an RF transmit amplifier unit. The control input receives a control signal and, dependent on the control signal, the control unit selects an operating value parameter set from the memory element. The control output controls an energy supply unit and/or a preamplifier/linearization element using the selected operating value parameter set such that the RF transmit amplifier unit is operable in a defined operating state.

Abstract: Methods and systems for determining a change of speed of an aircraft for enabling the avoidance of conflicts between aircraft trajectories. The method of determining a change in speed of an aircraft, comprises the steps of: defining a merge point and a tie point; monitoring a first aircraft; determining when the first aircraft passes the tie point; providing trajectory data; predicting a trajectory of a second aircraft using the trajectory data; defining a minimum permissible longitudinal spacing; predicting a longitudinal spacing between the first and second aircraft at the merge point based on the predicted trajectory; and if the minimum permissible longitudinal spacing is greater than the predicted longitudinal spacing then calculating a proposed change in speed of the second aircraft that will result in the longitudinal spacing between the first and second aircraft at the merge point being greater than or equal to the minimum permissible longitudinal spacing.

Abstract: The disclosure discloses a dynamic attitude measurement method of a star sensor based on gyro's precise angular correlation. On the basis that a dynamic compensation is performed on each of the measurement exposure frames of the star sensor and a fixed star matching vector matrix having dynamic error and noise influence is obtained in a prior art, a transform matrix between every two adjacent measurement frames of the star sensor is precisely measured by a unit including three gyros fixedly coupled with the star sensor. The transform matrix correlates the matched vector matrixes of the adjacent measurement frames of the star sensor. Finally, a correlated measurement equation is established with a series of correlated measurement frames, which is corresponding to processing a series of measurement frames as a single measurement frame.

Abstract: Methods and apparatuses are provided for managing a state of a platform. The methods and apparatuses comprise receiving a desired state for the platform. The methods and apparatuses comprise receiving the state of the platform. The methods and apparatuses comprise selecting a combination of thrusters from a plurality of thrusters to operate. The combination of thrusters is selected to adjust the state of the platform to the desired state. The methods and apparatuses operate the combination of thrusters to adjust the state of the platform to the desired state.

Abstract: A method and apparatus are presented for improving accuracy in a navigation system. A method of determining a physical characteristic of a receiving device in a navigation system, includes receiving a plurality of navigation signals from a plurality of navigation signal sources, respectively; determining a plurality of measurement estimates, based on the received navigation signals; and determining a physical characteristic of the receiving device by estimating a first set of one or more parameters in an error model, based on at least the plurality of measurement estimates. The error model includes a first error contribution for modeling noise and a second error contribution for modeling indirect signal propagation of the plurality of navigation signals.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for unmanned aerial vehicle authorization and geofence envelope determination. One of the methods includes maintaining, by a cloud system in wireless communication with Unmanned Aerial Vehicles (UAVs), allocated geofence envelopes for one or more of the UAVs, with each geofence envelope being a virtual barrier for a real-world geographic area. A request for approval of an updated geofence envelope is received from a first UAV in flight. The cloud system determines that the updated geofence envelope has not been allocated and/or the updated geofence envelope does not interfere with allocated geofence envelopes. In response to the determination, a response indicating approval of the request is generated. The generated response is provided to the first UAV.

Abstract: Methods and apparatuses are provided for managing a plurality of thrusters in a platform. The method and apparatuses comprise operating the plurality of thrusters in the platform with a thruster control system. The methods and apparatuses comprise estimating a vehicle response resulting from the operation of the plurality of thrusters to form an estimated vehicle response. The methods and apparatuses also comprise comparing the estimated vehicle response to a desired vehicle response to develop objective function errors. Also, the methods and apparatuses comprise developing a number of commands configured to correct the objective function errors.

Abstract: Three-axis spacecraft momentum management is performed for a spacecraft traveling along a trajectory, by an actuator including at least one thruster disposed on a single positioning mechanism. As the spacecraft travels along the trajectory, a desired line of thrust undergoes a substantial rotation in inertial space. When the spacecraft is located at a first location on the trajectory, the single positioning mechanism orients the thruster so as to produce a first torque to manage stored momentum in at least one of a first and a second of the three inertial spacecraft axes. When the spacecraft is located at a second location on the trajectory, the single positioning mechanism orients the thruster so as to produce a second torque to manage stored momentum in at least a third of the three inertial spacecraft axes.

Abstract: Apparatus and methods for raising the orbit of a satellite having electric propulsion thrusters, an Earth sensor and an inertial reference sensor such as a gyro. A satellite positioning system generates orbital data and a profile generator generates an ideal electric orbit raising profile of the satellite. The ideal profile is one that the satellite must follow so that the perigee, apogee and inclination of the satellite can be adjusted simultaneously in a mass-efficient manner. A state machine processes the ideal profile and a true anomaly to generate a desired electric orbit raising profile. Steering apparatus generates signals that are used to control the attitude of the satellite to follow the desired profile.

Abstract: One variation of a method for imaging an area of interest includes: within a user interface, receiving a selection for a set of interest points on a digital map of a physical area and receiving a selection for a resolution of a geospatial map; identifying a ground area corresponding to the set of interest points for imaging during a mission; generating a flight path over the ground area for execution by an unmanned aerial vehicle during the mission; setting an altitude for the unmanned aerial vehicle along the flight path based on the selection for the resolution of the geospatial map and an optical system arranged within the unmanned aerial vehicle; setting a geospatial accuracy requirement for the mission based on the selection for the mission type; and assembling a set of images captured by the unmanned aerial vehicle during the mission into the geospatial map.

Abstract: 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.

Abstract: Methods and apparatus are presented for spacecraft operation using non-Eigen axis attitude transitions via control momentum gyroscopes (CMGs) to avoid or mitigate singularities by providing a time-varying attitude command vector including a plurality of time-varying attitude command signals or values representing a plurality of spacecraft states and control trajectories as a guidance command input to an attitude controller of the spacecraft without modifying the spacecraft feedback control law.

Abstract: Systems and methods for performing airport surface collision-avoidance. A wingtip-mounted camera allows the pilot to positively ascertain that the wingtip will clear objects located in the video. An exemplary system implemented on an aircraft includes a wingtip module having a camera that generates a video stream and a communication device that transmits the generated video stream. A processor receives the video stream and generates a reticule for the video stream. A display device simultaneously presents the video stream and the reticule. The reticule includes a horizon line and is based on a focal length of a lens of the camera and height of the camera above ground. The reticule includes curved and/or straight distance lines and curved or straight travel lines. The travel line(s) correspond to at least one aircraft component or a zone of importance and are based on location of the camera and trajectory of the aircraft.

Abstract: 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.

Abstract: An ephemeris refinement system includes satellites with imaging devices in earth orbit to make observations of space-based objects (“target objects”) and a ground-based controller that controls the scheduling of the satellites to make the observations of the target objects and refines orbital models of the target objects. The ground-based controller determines when the target objects of interest will be near enough to a satellite for that satellite to collect an image of the target object based on an initial orbital model for the target objects. The ground-based controller directs the schedules to be uploaded to the satellites, and the satellites make observations as scheduled and download the observations to the ground-based controller. The ground-based controller then refines the initial orbital models of the target objects based on the locations of the target objects that are derived from the observations.

Abstract: In a system and method for navigating a moving object according to signals from satellite, a moving object receives satellite navigation signals from a number of satellites. The moving object also receives moving base data from a moving base. The received moving base data includes satellite measurement data of the moving base. At the moving object a relative position vector of the moving object relative to the moving base is determined, based on the received moving base data and the received satellite navigation signals. The moving object sends a signal reporting information corresponding to the relative position vector.

Abstract: In one or more embodiments, an apparatus and method for operating an unmanned and autonomous vehicle includes a sensor management module configured to direct sensors as to what function they are to provide; a mission management module configured to provide execute function capabilities; an effects management module configured to provide launching and directing weapons to their target capabilities; a vehicle management module; a situation awareness management module configured to provide correlate sensor data of objects, threats, targets, geographic points of interest that the pilot requires in the immediate environment; a communications management module; an information management module configured to provide a database of intelligence-related data; a middleware module configured to interface with the sensor management module, the mission management module, the effects management module, the vehicle management module, the situation awareness management module, the communications management module, and the inf

Abstract: A method for operating a controlled device. A feedback signal is received from a controlled device, the feedback signal indicating actual system dynamics of the controlled device. A predefined limit is applied to the actual system dynamics to create limited system dynamics. A modulation parameter is calculated by a processor based at least in part on the limited system dynamics and the actual system dynamics. Desired system dynamics for the controlled device are generated by the processor based at least in part on the modulation parameter and an external command.

Abstract: Technologies are generally described for controlling a flight path of a UAV based image capture system for solid modeling. Upon determining an initial movement path based on an estimate of a structure to be modeled, images of the structure to be modeled may be captured and surface hypotheses formed for unobserved surfaces based on the captured images. A normal vector and a viewing cone may be computed for each hypothesized surface. A set of desired locations may be determined based on the viewing cones for the entire structure to be modeled and a least impact path for the UAV determined based on the desired locations and desired flight parameters.

Abstract: A system includes a fluid reservoir containing a first fluid, a pair of fluidic channels in fluidic connection with the fluid reservoir, a counter-fluid reservoir having a second fluid that is non-miscible with the first fluid, and a pump connected to the fluid reservoir. The pump is configured to pump the first fluid from the fluid reservoir into the pair of fluidic channels. When contained in a vehicle, the system allows for control of the vehicle's orientation. The system may use sensor input to determine when to actuate the pump. Each fluidic channel may have a cross-section that varies along its length. The fluidic channels may be geometrically symmetric about the fluid reservoir. The system may be incorporated into a vehicle to control the vehicle's orientation.

Abstract: A highly reliable aerodynamic coefficient estimate can be computed, and computation of this aerodynamic coefficient estimate enables accurate detection of control surface failure/damage while reducing a discomfort for passengers. A deflection angle command signal generation means (5) generates a deflection angle command signal for estimating an aerodynamic coefficient indicating the aerodynamic characteristics of an airframe. A kinetic state quantity acquisition means (6) acquires a kinetic state quantity of the airframe that is obtained as a result of a control surface provided on the airframe being moved based on the deflection angle command signal. A candidate value calculation means (7) calculates candidate values for estimating the aerodynamic coefficient from the kinetic state quantity using two or more different estimations. An aerodynamic coefficient estimate determination means (8) determines an aerodynamic coefficient estimate based on the candidate values.

Abstract: A method of enhancing on-board state estimation for a spacecraft utilizes a network of assets to include planetary-based assets and space-based assets. Communication signals transmitted from each of the assets into space are defined by a common protocol. Data is embedded in each communication signal transmitted by the assets. The data includes a time-of-transmission for a corresponding one of the communication signals and a position of a corresponding one of the assets at the time-of-transmission. A spacecraft is equipped to receive the communication signals, has a clock synchronized to the space-wide time reference frame, and has a processor programmed to generate state estimates of the spacecraft. Using its processor, the spacecraft determines a one-dimensional range from itself to at least one of the assets and then updates its state estimates using each one-dimensional range.

Abstract: The disclosed method involves calculating, with at least one processor, a desired orbit for the spacecraft. The method further involves calculating a velocity change required to achieve an orbit eccentricity, a velocity change required to achieve a semi-major axis, and a velocity change required to achieve an orbit inclination; all of which correspond to the desired orbit for the spacecraft. Also, the method involves calculating the direction of the vector sum of the velocity change required to achieve the orbit eccentricity, the velocity change required to achieve the semi-major axis, and the velocity change required to achieve the orbit inclination. Further, the method involves activating at least one propulsion device of the spacecraft in the direction of the vector sum in order to change the current orbit of the spacecraft to the desired orbit for the spacecraft, thereby changing the orbit eccentricity, the semi-major axis, and the orbit inclination simultaneously.

Abstract: Systems and methods for determining a positional state of an airborne array antenna using distributed accelerometers are described.

Abstract: The present invention provides methods for positioning at least one component, in particular a seat, in or on an aircraft or spacecraft comprising the following steps: controlling at least one light source of the aircraft or spacecraft to display at least one desired position of at least one component; and positioning the at least one component in the at least one desired position displayed.

Abstract: Methods and systems are provided for controlling attitude of a vehicle using a reaction wheel onboard the vehicle. One exemplary method involves receiving a torque command for adjusting the attitude of the vehicle using the reaction wheel, determining a phase error of the reaction wheel based at least in part on the torque command, and determining a motor torque command for the reaction wheel based on the phase error. The motor torque command is provided to an electric motor of the reaction wheel to apply a corresponding torque to the rotor of the reaction wheel. The relationship between the magnitude of the motor torque command and the magnitude of the phase error is nonlinear. In exemplary embodiments, the magnitude of the motor torque command exceeds the stiction torque, at least instantaneously, when the reaction wheel has fallen behind an expected position by more than a threshold amount.

Abstract: 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.

Abstract: 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.

Abstract: Methods and apparatus are presented for spacecraft operation in which a control problem is formulated using a control law or steering law as a path constraint or as a dynamic constraint, and the control problem is solved to provide a guidance command trajectory for use in operating spacecraft control momentum gyroscopes to guide the spacecraft from an initial state to a desired final state.

Abstract: 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.

Abstract: 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.

Abstract: A vehicle driving force suppression device is provided, and driving force suppression is conducted on the basis of existence of an obstacle which is on the opposite course to the selected shift position. Adding specific conditions related to acceleration pedal depression amount and speed, inclination of the road in the direction which an obstacle exists, or distance to the obstacle, magnitude of driving force suppression is decided.

Abstract: A method for analyzing faults present on a platform includes the following steps: (a) providing a table of correspondence between a plurality of observable symptoms on the platform (10) and the fault modes capable of creating each observable symptom; (b) measuring the observable symptoms present on the platform (10); (c) establishing at least one family of faults, including determining a list of fault modes capable of creating, alone or in combination, all of the selected present symptoms, placing each given fault mode of the group in a fault family, and grouping all of the fault modes capable of creating at least one selected present symptom shared with the given fault mode together in the same fault family as the given fault mode. The method is applicable to fault analyses on aircrafts.

Abstract: It is presumed and commonly accepted by those skilled in the art of satellite navigation and Kalman filter design that the filter must be provided with the tracker position and velocity a priori in order to determine target position and velocity. Indeed, it is generally asserted that without a priori knowledge (known or measured values) of the tracker position and velocity, line of sight measurements between satellites do not contain adequate information to infer target states. Passive and autonomous navigation of space vehicles without a priori values for the position and velocity of either the target or tracker vehicle is achieved by reconfiguring the extended Kalman filter, or more generally any predictor/correction class filter, to include states for both the target and tracker vehicles. The target and tracker vehicles must both follow trajectories in an inertial frame of reference through the gravitational field of a gravitational body having a known gravitational model.

Abstract: A method of determining the reliability of long-term predicted orbit data, includes: determining the reliability of long-term predicted orbit data, which is acquired by predicting a satellite orbit in a target period of at least one day, using predicted position data including predicted positions of a positioning satellite in time series and actual position data including actual positions of the positioning satellite corresponding to the predicted positions.

Abstract: Systems and methods are operable to present graphical information indicating capability of an aircraft to change altitude. An exemplary embodiment determines an altitude change capability of the aircraft; determines an altitude change capability icon based on the determined altitude change capability of the aircraft, wherein the altitude change capability icon is defined by at least a leading portion, a trailing portion, a top portion, and a bottom portion, wherein a slope of the leading portion of the altitude change capability icon corresponds to the determined altitude change capability of the aircraft, and wherein the leading portion and the trailing portion are separated by at least the top portion and the bottom portion; and communicates the altitude change capability icon to a display for presentation to the crew of the aircraft.

Abstract: 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.