Abstract: Techniques for Ultra Wide-Lane (UWL) Real-Time Kinematic (RTK) positioning a mobile device may include obtaining, using a multi-band GNSS receiver of the mobile device: a first carrier-phase measurement of a first GNSS signal on a first GNSS carrier frequency, and a second carrier-phase measurement of a second GNSS signal on second GNSS carrier frequency. Techniques may further comprise providing a position estimate of the mobile device, wherein: the position estimate is determined from a wide-lane (WL) combination of the first carrier-phase measurement and the second carrier-phase measurement, and the WL combination has a combined carrier phase noise that is less than a pseudo-range noise of the first carrier-phase measurement and a pseudo-range noise of the second carrier-phase measurement.

Abstract: Systems and methods are described for computing a trajectory of an object in space to a secondary body (M2) in orbit around a primary body to land on, or capture into orbit, or flyby M2 in a Three-Or-More Body Problem. A special plotting of sampled vectors from M2 are integrated backward using a Poincaré Map to form a “Swiss Cheese plot” to find a nominal trajectory. A funnel-like set of trajectories can be constructed along the nominal trajectory for navigation purposes. A global resonant encounter map over a sphere around M2 can be constructed to provide trajectories to, for example, flyby any point near M2, capture into orbit over any point about M2, land on any point on M2. Besides space exploration, there are many applications to the development of Cislunar space commercialization and colonization including asteroid capture and mining.

Abstract: A system for optimizing a low-thrust trajectory of a spacecraft trajectory for orbital transfer includes an interface to receive data, a memory to store scheduled geostationary transfer orbit (GTO) data and scheduled geostationary Earth orbit (GEO) data and computer-executable programs, and a processor.

Abstract: A modular and scalable system to transfer space articles between space orbits. In one embodiment, the system employs a rendezvous vehicle which docks with a space article in an initial orbit, the connected stack then docking with a locomotive vehicle which maneuvers to a targeted orbit where the space article is detached. In one feature, the rendezvous vehicle and locomotive vehicle use a common propellant and the space article is a satellite.

Abstract: An approach is provided for delivering a configuration based workflow in an IT system. A set of parameters and pre-configured conditions associated with a command initiated for execution are determined. Validation action(s) that validate the command and are included in the configuration based workflow are determined. The validation action(s) are specified by respective interaction(s) with external system(s). Validation action(s) included in the configuration based workflow are performed by completing the interaction(s) with the external system(s) using the set of parameters. It is determined whether the validation action(s) are successfully completed. If the validation action(s) are successfully completed, the execution of the command is continued. If at least one of the validation action(s) is not successfully completed, the execution of the command is discontinued.

Abstract: An orbit transfer method for a spacecraft using a continuous or quasi-continuous thrust propulsion, the method comprises: the acquisition, at least once in each half-revolution of the spacecraft, of measurements of its position and of its velocity; the computation of a thrust control function as a function of the measurements; and the driving of the thrust in accordance with the control law; wherein the control law is obtained from a Control-Lyapunov function using orbital parameters, preferably equinoctial, of the spacecraft, averaged over at least one half-revolution. An embedded driving system for a spacecraft for implementing such a method and a spacecraft equipped with the driving system are provided.

Abstract: The invention relates to a method for operating a controlled object, that is embedded in a changing environment, wherein the controlled object and its environment are periodically observed using sensors, and, in each frame, at least three independent data flow paths (DFPs) are executed based on the data recorded through the observation of the controlled object and its environment.

Abstract: Energy efficient satellite maneuvering is described herein. One disclosed example method includes maneuvering a satellite that is in an orbit around a space body so that a principle sensitive axis of the satellite is oriented to an orbit frame plane to reduce gravity gradient torques acting upon the satellite. The orbit frame plane is based on an orbit frame vector.

Abstract: An approach is provided for delivering a configuration based workflow in an IT system. A command initiated for execution is identified as being included in a list of commands. A set of parameters and pre-configured conditions associated with the identified command are determined. Validation action(s) that validate the command and are included in the configuration based workflow are determined. The validation action(s) are specified by respective interaction(s) with external system(s). Validation action(s) included in the configuration based workflow are performed by completing the interaction(s) with the external system(s) using the set of parameters. It is determined whether the validation action(s) are successfully completed. If the validation action(s) are successfully completed, the execution of the command is continued. If at least one of the validation action(s) is not successfully completed, the execution of the command is discontinued.

Abstract: An apparatus for defining and generating boundaries of satellite coverage. The apparatus includes a processor that is configured to select a plurality of beam points, from a set of points on a coordinate system, to be included within a beam definition, and determine a number of ellipses capable of enclosing the selected beam points while excluding all remaining points of the set of points. The processor then assigns the selected beam points to a corresponding ellipse, and optimizes geometric information for each ellipse to enclose the beam points assigned thereto. A coverage beam is then defined based on a contour resulting from the combined shape of all the ellipses using the optimized geometric information.

Abstract: A spacecraft control system and method for determining the necessary delta-V and timing for impulsive maneuvers to change the plane of an orbit or the size of the orbit of a secondary spacecraft that is in an orbit around a primary spacecraft. The system and method uses an apocentral coordinate system for the relative orbital motion and geometric relative orbital elements to determine the required impulsive velocity change and time to maneuver, for relative orbital changes in which only one of slant or colatitude of the sinilaterating node changes.

Abstract: Eccentricity control for a geosynchronous satellite includes: setting initial conditions, duration, and schedule for the eccentricity control; defining a plurality of parameters including control loci for centroid, semi-major axis, semi-minor axis, uncontrolled eccentricity radius, right ascension of ascending node, and inclination, wherein the plurality of parameters are defined such that when the eccentricity control is applied, a mean geodetic longitude of the geosynchronous satellite is maintained within a predefined distance from a station longitude.

Abstract: A method estimates a state of a spacecraft in a planet-moon environment by executing iteratively a particle filter. The particle filter comprising integrates individually states of each particle of the particle filter according to a probability-evolution equation using a model of the state of the spacecraft represented as a planar circular restricted three-body problem and determines a prior probability of each particle as a previous posterior probability of a corresponding particle during a previous iteration. A joint probability distribution of the state of the spacecraft is determines using the states of each particle and the prior probabilities of each particle and the states and the prior probabilities of each particle are updated according to the joint probability distribution of the state of the spacecraft and a measurement of the state of the spacecraft to produce posterior probabilities of each particle.

Abstract: A spacecraft including at least one main propellant tank, a main engine fed with propellant by the main tank, and a de-orbiting device. The de-orbiting device includes a detonation engine fed with propellant by the main tank.

Abstract: A method of controlling the attitude of a satellite in orbit around a celestial body. The attitude of the satellite being controlled by a momentum storage device and controllable surfaces of the satellite configured to create desaturation torques in the storage device by using solar pressure. The controllable surfaces are arranged on solar panels mobile in rotation around an axis Y. At least one electric thruster configured to control the orbit of the satellite also controls the attitude of the satellite. The orientation of the electric thruster is controlled to activate the electric thruster with a thrust direction deliberately not aligned with a center of mass of the satellite to create desaturation torques in the storage device along axis Y. The controllable surfaces are controlled to create desaturation torques of the storage device in a plane orthogonal to the Y axis.

Abstract: For capturing satellites and other orbital objects, one or more independent capturing units are releasably arranged on a spacecraft serving as a steerable carrier vehicle. Each capturing unit has a propellant charge and at least one braking thrust nozzle of its own, and a closeable capture net releasably connected to the capturing unit via a tether line. The net is deployed from the capturing unit to capture the orbital object. Position or attitude control engines of the carrier vehicle are operated for orienting the combination including the capturing unit and the orbital object captured in the net. The capturing unit is then released from the carrier vehicle, and applies a braking thrust to the captured object so as to deorbit the captured object together with the capturing unit.

Abstract: A satellite inclination control method is provided. The method includes tracking optimal inclination vector control cycles for a satellite in near geosynchronous orbit, using control rates disposed to counter inclination growth of the satellite, where the control rates include continuously or quasi-continuously firings of a thruster, and where the control rates are disposed to provide convergence to the optimal inclination vector control cycles in the presence of variances in orbit determination, maneuver implementation and orbit propagation modeling errors.

Abstract: A method and apparatus for generating avoidance data. Strips are generated for a path of a space object. The strips are positioned relative to the path of the space object. The strips have parameters that obscure an identification of the path of the space object to form the avoidance data.

Abstract: A system and method for propelling spacecraft is disclosed. An electrical propulsion system is mounted on a base stage. A plurality of spacecraft couplers are also mounted on the base stage. Each spacecraft coupler securedly attaches a spacecraft to the base stage. Each spacecraft includes an internal power source that is coupled to the electrical propulsion system via an electrical connection. The internal power source consists of solar panels and/or batteries. A power regulation circuit is coupled between the electrical propulsion system and each internal power source. The power regulation circuit is draws an equal and proportional amount of power from each spacecraft. The spacecraft are preferably satellites and the electrical propulsion system preferably propels the base stage and attached satellites from a lower-Earth orbit to a higher-Earth orbit so that the electrical propulsion system in each satellite need only be capable of providing propulsion for orbit maintenance and maneuvering.

Abstract: A Kinetic Energy Storage and Transfer (KEST) vehicle and target vehicle kinetic energy transfer method are provided. The KEST vehicle is configured to transfer kinetic energy to the target vehicle, propelling the target vehicle into a higher orbit or beyond the Earth. This is accomplished by a catching mechanism that contacts the target vehicle. The catching mechanism may also include a braking mechanism configured to accelerate the target vehicle, and thus slow the KEST vehicle, as the catching mechanism and target vehicle travel along one or more tethers of the KEST vehicle. Alternatively, the catching mechanism may be attached to an end of the one or more tethers and be configured to slow the target vehicle as the one or more tethers bend.

Abstract: A method of controlling the attitude of a satellite in orbit around a celestial body. The attitude of the satellite being controlled by a momentum storage device and controllable surfaces of the satellite configured to create desaturation torques in the storage device by using solar pressure. The controllable surfaces are arranged on solar panels mobile in rotation around an axis Y. At least one electric thruster configured to control the orbit of the satellite also controls the attitude of the satellite. The orientation of the electric thruster is controlled to activate the electric thruster with a thrust direction deliberately not aligned with a center of mass of the satellite to create desaturation torques in the storage device along axis Y. The controllable surfaces are controlled to create desaturation torques of the storage device in a plane orthogonal to the Y axis.

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 propulsion system for the orbit control of a satellite in Earth orbit driven at a rate of displacement along an axis V tangential to the orbit comprises two propulsion modules, fixed to the satellite, and facing one another relative to the plane of the orbit, each of the propulsion modules comprising, in succession: a motorized rotation link about an axis parallel to the axis V; an offset arm; and a plate supporting two thrusters, suitable for delivering a thrust on an axis, arranged on the plate on either side of a plane P at right angles to the axis V passing through a centre of mass of the satellite; each of the two thrusters being oriented in such a way that the thrust axes of the two thrusters are parallel to one another and at right angles to the axis V.

Abstract: Eccentricity control for a geosynchronous satellite includes: setting initial conditions, duration, and schedule for the eccentricity control; defining a plurality of parameters including control loci for centroid, semi-major axis, semi-minor axis, uncontrolled eccentricity radius, right ascension of ascending node, and inclination, wherein the plurality of parameters are defined such that when the eccentricity control is applied, a mean geodetic longitude of the geosynchronous satellite is maintained within a predefined distance from a station longitude.

Abstract: An autonomous system for a satellite which calculates collision paths of debris from anywhere within the spheroid around the satellite by using its radar/ladar data and from data on its own orbit derived by onboard sensors such as star, earth and sun sensors or from stored data sent from its ground control station through the satellite's command subsystem. If a collision would be likely, the system calculates the minimum change in the satellite's orbit to avoid such collision and generates and executes commands for firing on-board orbital control thrusters to put the satellite in a suitable avoidance orbit.

Abstract: A method comprises removing space debris having a relatively low ballistic coefficient by hastening orbital decay of the debris. A transient gaseous cloud is created at an altitude of at least 100 km above Earth. The cloud has a density sufficient to slow the debris so the debris falls into Earth's atmosphere.

Abstract: A method is provided for controlling a set of at least two satellites adapted to provide a service used by at least one portion of the set of the said satellites at a given moment, in which, continuously or pseudo-continuously, a mean value of the longitudes of the respective ascending nodes of each satellite is computed, and, for each satellite, a correction of trajectory of the satellite is applied by regulating the longitude of the ascending node on a setpoint equal to said current mean value.

Abstract: Spacecraft transfer orbit operations include separating a spacecraft from a launch vehicle, while in a launch vehicle transfer orbit. The spacecraft includes a propulsion subsystem and a spacecraft controller that controls the spacecraft in a three-axis stabilized mode. With the spacecraft continuously in the three-axis stabilized mode, one or more orbit raising maneuvers are performed by firing either or both of a chemical thruster and an electric thruster firing. Any two consecutive orbit raising maneuvers are separated by a respective intervening coast period. While in the three-axis stabilized mode, the spacecraft does not rotate about any axis at a rate greater than 0.1 degree/sec and dumping of momentum stored in a reaction wheel system is avoided.

Abstract: A device for coupling with a space satellite before the satellite is launched for the purpose of de-orbiting said satellite and/or returning it to Earth. The device includes: controller for controlling the device; propulsion system operatively connected with the control means; receiver for receiving control signals operatively connected with the control means; powering system for electrically powering the device; coupler for mechanically coupling the device with the satellite before the satellite is launched. The propulsion system is enabled by the controller on receipt of control signals for deorbiting the satellite and transferring it to a given orbit.

Abstract: Systems, apparatuses, and methods for removal of orbital debris are provided. In one embodiment, an apparatus includes a spacecraft control unit configured to guide and navigate the apparatus to a target. The apparatus also includes a dynamic object characterization unit configured to characterize movement, and a capture feature, of the target. The apparatus further includes a capture and release unit configured to capture a target and deorbit or release the target. The collection of these apparatuses is then employed as multiple, independent and individually operated vehicles launched from a single launch vehicle for the purpose of disposing of multiple debris objects.

Abstract: The present disclosure relates to the deorbiting of satellites in low orbit that have entered safe hold mode. A device makes it possible to decide in an autonomous manner and on the basis of information existing in the satellite, when and where to trigger a series of short thruster manoeuvres to modify the satellite orbit with the aim of deorbiting.

Abstract: The focus of this invention pertains to the methodology behind launching line-scanning satellite constellations that can image an entire planet such as the Earth at high temporal cadence (less than a week), at high spatial resolution (less than 10 m). Utilizing simple control and operation, our invention captures images of an entire planet in an effective and distributed manner. Additional benefits are realized by taking advantage of the distributed onboard storage and computing abilities of such a constellation to optimize the data collected, system latency, and data downlinked.

Abstract: An apparatus and method for controlling a geostationary orbit satellite is provided. The method including generating remote measurement data by measuring a state of a geostationary orbit satellite, transmitting the remote measurement data, receiving a remote command signal, and controlling an orbit and a pose of the geostationary orbit satellite relative to inclined geosynchronous space debris.

Abstract: A propulsion system for controlling the orbit of a satellite in earth orbit comprises a thruster suitable for delivering a force along an axis F, and a motor-driven mechanism linked on the one hand to the thruster and on the other hand to a structure of the satellite, said motor-driven mechanism being suitable for displacing the thruster on either side of the plane of the orbit and suitable for orienting the thruster so as to make it possible to control a component perpendicular to the orbit of the force in two opposite directions, to control the inclination of the satellite, and in that said motor-driven mechanism is suitable for displacing the thruster along an axis V parallel to the velocity of the satellite, and suitable for orienting the thruster so as to make it possible to control a component of the force on the axis V, to control orbit.

Abstract: The systems and methods of the invention modulate atmospheric gases to temporarily increase the amount of atmospheric particles in the path of the debris, in order to decelerate the debris and accelerate natural orbital decay to the point of atmospheric re-entry. In one aspect of the invention, clearing the space debris includes propelling a plume of atmospheric gases substantially orthogonal to the path of the debris such that the debris collides with the gaseous plume as it passes through the plume. Increased atmospheric drag from the gaseous particles of the plume in the path of the debris obstructs a forward propagation of the debris and gradually decelerates the debris, leading eventually to atmospheric recapture.

Abstract: System and method for inducing rapid reentry of orbital debris including determining a spatial extent of the orbital debris, and deploying dust to the orbital debris to enhance the drag on the orbital debris. Small objects with perigee above about 900 km where the debris lifetime can be centuries can be targeted for de-orbiting.

Abstract: A propulsion system for the orbit control of a satellite with terrestrial orbit having an angular momentum accumulation capacity comprises a propulsion unit able to deliver a force along an axis F having a component perpendicular to the orbit, and a motorized mechanism connected on the one hand to the propulsion unit and on the other hand to a structure of the satellite, the motorized mechanism being able to displace the propulsion unit along an axis V parallel to the velocity of the satellite, and able to orient the propulsion unit so as to make it possible to control: a component of the force along the axis V, for orbit control, an amplitude and a direction of couple in a plane perpendicular to the axis F, for control of the angular momentum.

Abstract: System and method for inducing rapid reentry of orbital debris including determining a spatial extent of the orbital debris, and deploying dust to the orbital debris to enhance the drag on the orbital debris.

Abstract: A satellite longitude and drift control method is provided that includes providing a satellite that has a continuously or a quasi-continuously firing thruster, where the thruster is disposed to apply accelerations which counter a tri-axiality displacement in an orbit of the satellite, and the satellite thruster is disposed to achieve optimal ?V performance in the presence of orbit determination and orbit propagation errors. The method further includes targeting an optimal two-phase continuous acceleration target cycle using the continuously or the quasi-continuously firing thruster, providing a closed loop and a hybrid loop implementation of the thruster firing, where the hybrid loop implementation includes an open and closed loop implementation, and where the closed loop and the hybrid loop implementations are disposed to provide quasi-continuous implementations of an optimal continuous control program.

Abstract: A method is provided for controlling a set of at least two satellites adapted to provide a service used by at least one portion of the set of the said satellites at a given moment, in which, continuously or pseudo-continuously, a mean value of the longitudes of the respective ascending nodes of each satellite is computed, and, for each satellite, a correction of trajectory of the satellite is applied by regulating the longitude of the ascending node on a setpoint equal to said current mean value.

Abstract: In some embodiments of the invention, methods and devices are provided that perturb a trajectory of a space-orbital object. For example, a spacecraft may be sent to a location near a space-orbital object orbiting the Earth. A net may be released from the spacecraft in a manner (e.g., with a given alignment, direction and velocity) that results in the net contacting and/or entangling with the object. This contact or entanglement may alter a velocity of the space-orbital object and thereby may alter its orbital path. In some instances, the net's velocity is sufficient to experience increase drag by the Earth's atmosphere, relative to the drag it would have otherwise experienced if the net did not contact the object.

Abstract: A method of flying a constellation of inclined geosynchronous satellites at the same station longitude with specific spacing but without the possibility of collision and provides the basic equations defining the initial positions of satellites such that the satellites will continue to remain in synchronized positions relative to each other for a number of years with little or no north-south positioning. In preferred embodiments the number of satellites in the constellation is five or ten. Communication with the satellites in the constellation is provided with existing prior art tracking radio systems.

Abstract: The present invention is directed to mitigating orbital debris in outer space by concentrating the plasma existing in space. The debris mitigation method involves sending a satellite device 1 into space that can concentrate local plasma in a surrounding region to create a relatively high density plasma field 5. The satellite device 1 comprises a plasma concentrator. By sending such a satellite device 1 into a desired obit where debris are to be mitigated, the debris passing through the created high density plasma field 5 is caused to encounter a drag force, which results in a faster orbital decay for the debris. Multiple devices may work in cooperation to influence the same orbital debris or to mitigate debris over a larger area.

Abstract: A spacecraft (P) has a propulsion system making it possible to exert a force of variable magnitude and orientation on the spacecraft, a control system designed to control the propulsion system in terms of magnitude and orientation so as to make the spacecraft approach a target around a planet, with the aid of a force having at least one component (fx, fy, fz), in the rotating reference frame tied to the target, which depends substantially linearly on the corresponding coordinate (x, y, z) of the craft in this reference frame.

Abstract: Space tug vehicles and methods for providing space tugs and moving target vehicles are provided. More particularly, a space tug utilizing electrostatic or Coulomb force for acting on target vehicles and for moving the target vehicles into new orbits or altitudes are provided. The space tug may establish an attractive electrostatic force by controlling the electrical potential of the space tug so that it is opposite the electrical potential of a target vehicle. The target vehicle may acquire an absolute electrical potential due to its interaction with the space plasma and photoelectrons or the space tug may impart additional charge to the target vehicle. After establishing the attractive electrostatic force, a propulsion system of the space tug is operated to provide thrust. Thrust is directed to change the orbit and/or position of the target vehicle that is being pulled towards the space tug by the electrostatic force.

Abstract: Spacecraft vehicles and methods for providing reorbiters capable of moving target objects are provided. More particularly, a reorbiter utilizing electrostatic or Coulomb force for acting on target objects and for moving the target objects into new orbits or altitudes are provided. The reorbiter may establish an electrostatic force by controlling the electrical potential of the reorbiter through active charge emission. The target object may acquire an electrical potential due to its interaction with the space plasma and photoelectrons or the reorbiter may impart additional charge to the target object. After establishing the electrostatic force, a propulsion system of the reorbiter is operated to provide thrust. Thrust is directed to change the orbit and/or position of the target object that is being moved by the electrostatic force between the reorbiter and the target object.

Abstract: Methods and systems are provided for orienting an agile vehicle using a control moment gyroscope array. A method comprises obtaining initial vehicle parameters for the vehicle and obtaining target vehicle parameters for the vehicle. The method further comprises determining command parameters based on a difference between the target vehicle parameters and the initial vehicle parameters, and simulating operation of the control moment gyroscope array using the command parameters and a torque value being at least equal to a maximum achievable torque for the control moment gyroscope array. When the simulated vehicle parameters are substantially equal to the target vehicle parameters, the method further comprises determining a torque profile for the control moment gyroscope array based on the simulated operation and operating the control moment gyroscope array using the torque profile.

Abstract: A deorbit device comprising a passive electrodynamic conductive tape connected at one end to a spacecraft.

Abstract: An onboard solar cell array current and voltage characteristic determination method is preferably used on small spacecraft and determines the solar cell orientation relative to the sun by a comparison between prelaunch solar cell characteristics with on-orbit solar cell characteristics well suited for spin axis determinations and monitoring the degradation of on-orbit solar cells over the operational life of a picosatellite.

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.