Systems and methods for describing, simulating and/or optimizing spaceborne systems and missions. Configurations for spaceborne systems are generated and validated based on simulation output.

Systems and methods are provided for high fidelity long-duration autonomous spacecraft navigation relative to a planet's surface and measuring the dynamics of the planet. For a planet like Earth, embodiments of the present disclosure can be used to estimate the unpredictable components of Earth's orientation with respect to the inertial frame. Embodiments of the present disclosure further enable autonomous landmark navigation by providing systems and methods for satellites to autonomously recognize landmarks, using, for example, multiple computer vision approaches to recognize multiple types of landmarks.

A method for providing optimized power balanced low thrust transfer orbits utilizing split thruster execution to minimize an electric orbit raising duration of an apparatus includes monitoring an electric power balance on the apparatus. The method also includes firing a first thruster in response to the apparatus exiting an eclipse and based on the electric power balance. The method additionally includes firing a second thruster at a predetermined time delay after firing the first thruster based on the electric power balance. The method additionally includes ending firing one of the first thruster or the second thruster after a predetermined time duration based on the electric power balance. The method further includes ending firing another of the first thruster or the second thruster in response to the apparatus entering a next eclipse.

An attitude control apparatus (20) includes an ideal thrust direction calculator (22), an ideal attitude calculator (24), a target attitude calculator (26), and a torque calculator (28). The ideal thrust direction calculator (22) calculates an ideal thrust direction of a thruster. The target attitude calculator (26) calculates a target attitude that is the attitude of a satellite in which a deviation from an ideal attitude is minimized within a movement limitation of an attitude control actuator (14) while a panel surface faces the sun. The torque calculator (28) calculates a torque for turning the satellite from an actual attitude to the target attitude and transmits a torque instruction to the attitude control actuator (14).

The present invention relates to a modular architecture for a resilient extensible SmallSat (MARES) command and data handling (C&DH) device used in a spacecraft, the modular architecture which conforms to a 1U CubeSat board area form factor, including: a C&DH processor card disposed on a backplane of the form factor; a C&DH processor card disposed on a backplane of the form factor; a fault tolerant field programmable gate array (FPGA) disposed on the C&DH processor card, the FPGA including an embedded fault tolerant memory controller, and a soft-core processor which runs core flight software on a real-time executive for a multiprocessor operating system; and a C&DH auxiliary card disposed on the backplane and used in conjunction with the C&DH processor card, to provide processing capability for the spacecraft, the auxiliary card which contains peripheral interface drivers and read electronics for monitoring a health and safety of the spacecraft.

Systems and methods for describing, simulating and/or optimizing spaceborne systems and missions. Configurations for spaceborne systems are generated and validated based on simulation output.

A satellite includes a plurality of thrusters disposed about the satellite, each of the plurality of thrusters having a minimum thruster firing time, and a control circuit connected to the plurality of thrusters. The control circuit is configured to identify violations of the minimum thruster firing time in a non-compliant thruster firing pattern selected to achieve a specified movement, generate a plurality of compliant thruster firing patterns by replacing each of the violations of the non-compliant thruster firing pattern by zero and a minimum time in different combinations, select a compliant thruster firing pattern from the plurality of compliant thruster firing patterns to produce a satellite movement that is within a predetermined range of the specified movement, and cause the plurality of thrusters to fire according to the compliant thruster firing pattern.

The present disclosure relates to an upper-atmospheric mass density prediction model with robust and reliable uncertainty estimates in accordance with various embodiments of the present disclosure. The upper-atmospheric mass density model is developed based on the SET HASDM density database. In various embodiments, PCA is used to reduce the spatial dimension of the dataset. The input sets used to train the mass density model contains a time series for the geomagnetic indices. The mass density prediction model is trained to output a mass density map for accurately prediction trajectories of satellites. For example, a likelihood of collision associated with a given object can be determined based at least in part on the mass density map. Analysis of the mass density map along with the likelihood of collision can used to determine a trajectory for the given object in space.

Drift-based rendezvous control system for controlling an operation of a spacecraft to rendezvous the spacecraft to a goal region over a finite time (FT) horizon. The system including accepting data including values of spacecraft states at a specified time period within the FT horizon. A processor at the specified time period selects a set of drift regions corresponding to a desired goal region at a location on an orbit where the target is located at the specified time period. Update a controller having a model of dynamics of the spacecraft with the accepted data. Formulate the set of drift regions as a penalty in a cost function of the updated controller. Generate control commands resulting in a real-time drift-based control policy where upon entering the drift region, the thrusters are turned off in order to minimize an amount of operation of the thrusters while rendezvousing with the desired goal region.

Provided are a method for maintaining Walker constellation formation and a terminal device. The method comprises: determining a first offset amount of each satellite within a simulation time period according to parameters of a Walker constellation; performing first offset on each satellite according to the first offset amount to obtain a Walker constellation after the first offset; determining a second offset amount of each satellite within the simulation time period according to parameters of the Walker constellation after the first offset; and superimposing the first offset amount and the second offset amount, and performing second offset on each satellite so as to maintain the formation of the Walker constellation.