A multi-mode thruster system for use in a spacecraft includes a microwave source; a cavity coupled to the microwave source and including a first inlet to receive a first fluid and a second inlet to receive a second fluid; and a nozzle provided at one end of the cavity. The thruster operates in a microwave electrothermal thruster (MET) mode to (i) generate a standing wave in the cavity using the microwave source and (ii) raise a temperature of the first fluid to generate a first hot gas that exits the cavity via the nozzle to generate thrust. The thruster operates in a chemical propulsion mode to (i) produce a reduction-oxidation reaction between the first fluid and the second fluid and (ii) generate a second hot gas that exits the cavity via the nozzle to generate thrust.

This patent presents an attitude determination and control system based on a Quaternion Kalman Filter (QKF) with an extendable number of sensors and actuators. Furthermore, it is compatible with the spherical motor as its attitude actuator. The system includes a processor with a QKF, at least one direct attitude actuator, and at least two environmental sensors. Firstly, system dynamics calculates a first propagation attitude determination result. Next, update the first propagation with the attitude sensor measurements. Then, control the satellite's attitude via the attitude actuator closer to the attitude command provided by the user. The proposed system dynamic model could adjust the number of actuators and sensors freely without reprogramming the algorithms for new missions with new configurations on the actuators and sensors. Moreover, if some components fail, the algorithm can automatically remove those related sequences to avoid the overall failure of the system.

A method for controlling a satellite using magnetics only, and a control system for implementing the method. The method involves assessing a current attitude of a satellite at a current time and location using magnetometry; setting a desired attitude for the satellite at a future time in a future location; developing a set of waypoints that provide the attitude of the satellite at plural locations between the current location and the future location; and actuating a plurality of magnetorquers to induce torques that achieve a small as possible difference between the attitude of the satellite between each waypoint and achieving the desired attitude at the future location, the magnetorquers being the sole means of inducing rotation of the satellite to attain the desired attitude.

In a spacecraft for operating a thruster that includes a microwave source, a resonant cavity, and a source of propellant which the thruster converts to hot gas and directs via a nozzle to generate thrust, a method includes operating the thruster in an ignition mode in which the microwave source outputs power at a first rate, and operating the thruster in a propulsion mode in which the microwave source outputs power at a second rate higher than the first rate.

A method for monitoring position of and controlling a second nanosatellite (NS) relative to a position of a first NS. Each of the first and second NSs has a rectangular or cubical configuration of independently activatable, current-carrying solenoids, each solenoid having an independent magnetic dipole moment vector, μ1 and μ2. A vector force F and a vector torque are expressed as linear or bilinear combinations of the first set and second set of magnetic moments, and a distance vector extending between the first and second NSs is estimated. Control equations are applied to estimate vectors, μ1 and μ2, required to move the NSs toward a desired NS configuration. This extends to control of N nanosatellites.

Enclosures for facilitating activities in space, and associated systems and methods, are disclosed. A representative system includes a spacecraft having an enclosed interior volume (which can be formed by an inflatable membrane) and one or more unmanned aerial vehicles (UAVs) carried by the spacecraft and positioned to deploy into the enclosed interior volume. The system can include a remote-control system to control the one or more UAVs from a terrestrial location while the spacecraft is in space. A wireless charging system can provide electrical power to the one or more UAVs. A representative method includes configuring one or more controllers to launch a first spacecraft to a first orbit, launch a second spacecraft to a second orbit, move the first spacecraft to the second orbit, dock the first spacecraft with the second spacecraft, and broadcast an event within an interior volume of the first spacecraft to a terrestrial location.

Systems and methods for transferring, storing, and/or processing materials, such as fuel or propellant, in space, are disclosed. A representative system includes a flexible container that is changeable between a stowed configuration in which the flexible container is contained within a satellite, and a deployed configuration in which the flexible container extends away from the satellite. The system can include a tanker with a storage container to dock with and refuel a satellite. Another representative system includes a controller programmed with instructions that position a spacecraft with a storage container in a first orbit, transfer the spacecraft to a second orbit, dock the spacecraft with a satellite in the second orbit, transfer material between the storage container and the satellite, undock the spacecraft from the satellite, and, optionally, return the spacecraft to the first orbit. An androgynous coupling system with mechanical and fluid connectors facilitates docking and material transfer.

A method and system is described for determining attitude for a satellite. A two-axis ram sensor head measures neutral winds and provides a density of the neutral winds. A three-axis magnetometer measures a geomagnetic field. A measurement interface module calculates attitude information, which includes three-axis attitude knowledge of a satellite relative to a local-vertical local-horizontal orbit frame, based on the combined ram measurements and magnetic field measurements, and provides the attitude information to a satellite that comprises the attitude sensor system.

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.

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.