Systems and method for controlling the attitude maneuvers of a spacecraft in space are provided. The method automatically generates optimal trajectories in real-time to guide a spacecraft, providing a much more robust and efficient method than predefined trajectories, to model errors or disturbances. These methods do not rely in predefined trajectories and their associated feed-forward term. The systems comprise sensors, attitude control mechanisms, and a control module to orient the spacecraft in real-time, such that the spacecraft reaches a desired target attitude following an optimal path in the state space and is locally and asymptotically stable.

A spacecraft includes: an ejector that ejects an object being a base of a shooting star at a speed of 120 m/s or more; a direction controller that controls a direction in which the object is ejected; and a position controller that controls a position at which the object is ejected. The ejector sequentially ejects objects at a predetermined time interval. The ejector controls a time interval individually for each of the objects. The spacecraft includes an autonomous controller that autonomously controls the ejector, direction controller, and position controller, to eject the object in a predetermined ejecting direction and at predetermined ejecting position and speed. The autonomous controller controls ejection of the object based on a result of determination on measurement data individually performed by each of arithmetic units.

A compact celestial tracker includes a platform, a rotation stage that rotatably coupled to the platform to rotate a plane of the platform about a rotation axis and that supports the platform on a substrate, an off-axis parabolic mirror mounted to one side of the platform and having a focal plane directed at an acute angle that is between the rotation axis and the plane of the platform to reflect and focus the beam at a point above another side of the platform, and a detector coupled to the other side of the platform to receive and detect the reflected and focused beam.

Provided are an earth satellite attitude data fusion system and method, applicable to an earth satellite space environment to estimate attitude data of a satellite. When the earth satellite attitude data fusion system of the present invention is used to perform the earth satellite attitude data fusion method, the first step is to perform a body rates/quaternion attitude data processing operation. Then, the next step is to perform an attitude/rates data fusion processing operation, wherein an attitude data fusion algorithm module receives a first IAE result data from a first EKF, and a second IAE result data from a second EKF, and performs an attitude/rates data fusion algorithm in a subsystem level to evaluate an attitude estimation IAE performance based on the first IAE result data, and the second IAE result data.

A control system for a spacecraft for determining a resultant torque that is exerted upon a spacecraft by one or more magnetic torque rods is disclosed. The spacecraft is configured to revolve around a celestial body in an orbit. A magnetic field of the celestial body is predictable, and a direction of the magnetic field located around the orbit is fixed. The control system includes the one or more magnetic torque rods, one or more processors in electronic communication with the one or more magnetic torque rods, and a memory coupled to the one or more processors. The memory stores data into a database and program code that, when executed by the one or more processors, causes the control system to instruct the one or more magnetic torque rods to exert the resultant torque upon the spacecraft.

An antenna system is configured for use in Low Earth Orbit (LEO) around Earth. The system has a plurality of antenna satellites coupled together to form a phased array. Each of the plurality of antenna satellites have an antenna body with an antenna and a solar cell. A processing device determines an orientation of the plurality of antenna satellites and position the phased array in the orientation based on an analysis of the solar cell of the antenna bodies facing the sun, the antenna of the antenna bodies facing the Earth, and maintaining a torque equilibrium of the phased array.

A satellite orbiting in one of a plurality of orbital planes of a satellite constellation system at an altitude range corresponding to low earth orbit includes at least one processor configured to generate satellite state data, and to generate a navigation signal based on the satellite state data. The satellite includes at least one transmitter configured to transmit the navigation signal for receipt by at least one client device on earth. Each of the plurality of orbital planes includes a corresponding one of a plurality of satellite subsets of a plurality of satellites of the satellite constellation system. Each of the plurality of orbital planes is within the altitude range, and the plurality of orbital planes includes a set of inclined orbital planes at a non-polar inclination.

A satellite attitude data fusion system and method is disclosed, applicable to the earth satellite environment to estimate attitude data of the satellite. When the satellite attitude data fusion system of the present invention is used to perform the satellite attitude data fusion method, the first step is to perform a body rates quaternion attitude data processing operation. Then, the next step is to perform an attitude/rates data fusion processing operation, wherein an attitude data fusion algorithm module receives the first IAE result data from the first EKF, and the second JAE result data from the second EKF, and performs an attitude/rates data fusion algorithm in a subsystem level to evaluate an attitude estimation JAE performance.

A method for desaturating reaction wheels of a spacecraft having a magnetic dipole is provided. The method includes orienting the spacecraft relative to an external magnetic field to apply a torque to the spacecraft via the magnetic dipole in a direction opposing momentum stored in the reaction wheels; and using the applied torque to unload at least some of the momentum stored in the reaction wheels. A corresponding spacecraft and non-transitory computer-readable medium are also provided.

A compact SFS may can be deployed in small space vehicles. The SFS may have a small size, weight, and low power requirements. The hardware, software, catalogs, and calibration algorithm of the SFS provide highly accurate attitude information that can be used for pointing. For instance, accurate attitude determination may be provided that supports pointing of a deployable high gain helical antenna. A full “lost in space” attitude solution, accurate to about an arcminute, may be accomplished in under a minute. The SFS may be fully reprogrammable on orbit, allowing continued algorithm development and deployment after launch.