Patent classifications
B64G1/244
RETRACTABLE Z-FOLD FLEXIBLE BLANKET SOLAR ARRAY
A solar array structure for a spacecraft includes one or a pair of flexible blanket or other foldable solar arrays and a deployable frame structure. The deployable frame structure includes a T-shaped yoke structure, a T-shaped end structure, and one or more rigid beams, the T-shaped yoke structure connectable to the spacecraft. When deployed, the frame structure tensions the flexible blanket solar array or arrays between the T-shaped yoke structure and the T-shaped end structure. When stowed, the flexible blanket solar array or arrays are folded in an accordion manner to form a stowed pack or packs between the cross-member arms of the T-shaped yoke structure and the T-shaped end structure, also stowed in its own Z-fold arrangement. The cross-member arms of the T-shaped end structure can include a solar array that can provide power before deployment while the flexible blanket solar array is stowed.
SPACECRAFT, COMMUNICATION METHOD, AND COMMUNICATION SYSTEM
A disclosed spacecraft is provided with: an attitude control actuator configured to control an attitude of the spacecraft; an imaging device configured to receive an optical communication signal from another spacecraft; and an attitude controller configured to control the attitude control actuator, based on a position of the optical communication signal in an image obtained by the imaging device.
METHOD FOR ORBIT CONTROL AND DESATURATION OF A SATELLITE BY MEANS OF ARTICULATED ARMS SUPPORTING PROPULSION UNITS
A method for orbit control of a satellite in orbit around the Earth and for desaturation of an angular momentum storage device of satellite is disclosed having two articulated arms each supporting a propulsion unit. The method includes determining a maneuver plan having at least two thrust maneuvers, a first thrust maneuver to be executed using the propulsion unit of one of the articulated arms and a second thrust maneuver to be executed using the propulsion unit of the other articulated arm, controlling the articulated arms and the propulsion units according to the maneuver plan, at least one of the first and second thrust maneuvers being a thrust maneuver referred to as discontinuous, composed of at least two separate consecutive thrust sub-maneuvers.
System and Method for the Improvement of Attitude Control System Testbeds for Small Satellites
A rotational negative-inertia converter (RNIC) has a housing enclosing a flywheel configured to rotate around an axis of symmetry; a motor with a stator attached to the housing and a rotor attached to the flywheel to rotate it around the axis of symmetry; a housing angular accelerometer attached to said housing; a flywheel angular accelerometer; and a controller configured to receive measured accelerometer values from the accelerometers. The controller is configured to drive the motor to maintain the angular acceleration of the flywheel at a value proportional to the housing angular acceleration, with a predetermined proportionality constant.
A method for calibrating an ADCS testbed comprising a DUT holder with three RNICs includes: using measured angular velocities of the DUT holder and RNIC flywheels, and ZGT data, to compute moments of inertia of the DUT holder with and without a satellite with ADCS, allowing compensation for those moments by the RNICs.
INTERLOCKING, RECONFIGURABLE, RECONSTITUTABLE, REFORMABLE CELL-BASED SPACE SYSTEM
Cell-based systems may interlock in a reconfigurable configuration to support a mission. Space systems, for example, of a relatively large size may be assembled using an ensemble of individual “cells”, which are individual space vehicles. The cells may be held together via magnets, electromagnets, mechanical interlocks, etc. The topology or shape of the joined cells may be altered by cells hopping, rotating, or “rolling” along the joint ensemble. The cells may be multifunctional, mass producible units. Rotation of cell faces, or of components within cells, may change the functionality of the cell. The cell maybe collapsible for stowage or during launch.
Method for orbit control and desaturation of a satellite by means of a single articulated arm carrying a propulsion unit
A method (50) for orbit control of a satellite (10) in Earth orbit and for desaturation of an angular momentum storage device of the satellite, the satellite (10) including an articulated arm (21) suitable for moving a propulsion unit (31) within a motion volume included in a half-space delimited by an orbital plane when the satellite is in a mission attitude, the method (50) including a single-arm control mode using only the propulsion unit (31) carried by the articulated arm (21), the single-arm control mode using a maneuvering plan including only thrust maneuvers to be executed when the satellite (10) is located within an angular range of at most 180° centered on a target node in the orbit of the satellite (10), including two thrust maneuvers to be performed respectively upstream and downstream of the target node.
Embedded Electrospray Thruster
An electrospray thruster with integrated propellant storage directly embedded into small satellite structural elements integrates the volume of the thruster into the volume of the rail.
Low earth orbit satellite communication system employing beam-hopping
The disclosed method for a communication satellite may include (1) simultaneously generating a first transmission beam to a first ground station and a second transmission beam to each of a plurality of second ground stations in sequence according to a schedule, (2) simultaneously receiving a third transmission beam from the first ground station and a fourth transmission beam from each of the second ground stations in sequence according to the schedule, (3) forwarding first data received via the third transmission beam to each of the second ground stations via the second transmission beam, and (4) forwarding second data received via the fourth transmission beam from each of the second ground stations to the first ground station via the first transmission beam. Various other methods and systems are also disclosed.
Attitude control device for a satellite and method for controlling the attitude of a satellite
An attitude control apparatus for a satellite includes: at least three electric motors, wherein the at least three electric motors are arranged in such a way that a torque may be generated with any orientation of an associated torque vector, and a controller, wherein the controller is configured to drive the at least three electric motors based on a torque controller. The torque controller is adapted to operate the at least three electric motors outside a rest state only when an acceleration torque and a braking torque are required to execute an agile attitude change maneuver. There is also described an associated method.
Satellites having autonomously deployable solar arrays
Satellites having autonomously deployable solar arrays are disclosed. A disclosed example satellite includes a solar array, a sensor to detect that the satellite has exited a launch vehicle, a processor to enable ignition of squibs of a squib array based on the satellite exiting the launch vehicle, and a squib controller to control the ignition of the squibs based on a firing sequence of the squibs, where the squib controller is to vary the firing sequence to autonomously deploy the solar array.