Apparatus and methods for controlling a spacecraft for a transfer orbit. The spacecraft includes a propulsion subsystem with electric thrusters that are installed with two-axis gimbal assemblies. The spacecraft also includes a controller that identifies a target spin axis for the spacecraft, determines an actual spin axis for the spacecraft during the transfer orbit, determines gimbal angles for the electric thruster(s) that adjust the actual spin axis toward the target spin axis, and initiates a burn of the electric thruster(s) at the gimbal angles.

A method for attitude control of a satellite in inclined low orbit in survival mode is disclosed, the satellite including at least one solar generator, at least one solar sensor, magnetic torquers capable of forming internal magnetic moments in a satellite reference frame having three orthogonal axes X, Y, and Z, and inertial actuators capable of forming internal angular momentums in the satellite reference frame. The at least one solar sensor has a field of view at least 180° wide within the XZ plane around the Z axis, the method including a step of attitude control using a first control law, a step of searching for the sun by means of the at least one solar sensor, when a first phase of visibility of the sun is detected, and a step of attitude control using a second control law.

A modular satellite for converting solar energy to microwave energy and transmitting the microwave energy to the earth to be converted into electricity includes solar panels configured to convert solar energy into direct current; a magnetron operatively connected to the solar panels to receive the direct current and configured to convert the direct current into microwave energy; a planar wave guide antenna operatively connected to the magnetron to receive the microwave energy and direct the microwave energy to a station on earth; and a coupling system for coupling with another satellite to form an array in response to at least one of locking, unlocking, and navigational commands. The satellite has a mass equal to or less than four kilograms, and a volume equal to or less than three liters.

A method and apparatus for the control of the attitude of earth orbiting satellites and the orbit and attitude control of a novel gravitational wave detection satellite configuration located near the sun-earth Lagrangian points L3, L4 and L5, utilizing the control of solar radiation pressure by the use of electrically controllable variable reflection glass panels to provide the torques and forces needed.

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.

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.

The invention is methods for landing rockets with precision using deep reinforcement learning for control. Embodiments of the invention are comprised of three steps. First, sensors collect data about the rocket's physical landing environment, passing information to rocket's database and processors. Second, the processors manipulate the information with a deep reinforcement learning program to produce instructions. Third, the instructions command the rocket's control system for optimal performance during landing.

The invention is methods for landing rockets with precision using deep reinforcement learning for control. Embodiments of the invention are comprised of three steps. First, sensors collect data about the rocket's physical landing environment, passing information to rocket's database and processors. Second, the processors manipulate the information with a deep reinforcement learning program to produce instructions. Third, the instructions command the rocket's control system for optimal performance during landing.

A control system includes a target spacecraft and a swarm of chaser spacecraft. Each chaser spacecraft is controlled to follow a corresponding computed trajectory. The system also includes at least one computing device that executes a nested genetic algorithm. The nested genetic algorithm includes multiple guidance genetic algorithms and an outer genetic algorithm. Characteristically, each chaser spacecraft has an associated guidance genetic algorithm that determines a computed trajectory for the chaser spacecraft associated therewith. Advantageously, the outer genetic algorithm checks for collisions and is configured to alter one or more computed trajectories to avoid collisions.

A control system includes a target spacecraft and a swarm of chaser spacecraft. Each chaser spacecraft is controlled to follow a corresponding computed trajectory. The system also includes at least one computing device that executes a nested genetic algorithm. The nested genetic algorithm includes multiple guidance genetic algorithms and an outer genetic algorithm. Characteristically, each chaser spacecraft has an associated guidance genetic algorithm that determines a computed trajectory for the chaser spacecraft associated therewith. Advantageously, the outer genetic algorithm checks for collisions and is configured to alter one or more computed trajectories to avoid collisions.