Patent classifications
B64G1/24
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.
Tracking neighboring quasi-satellite orbits around Mars's moon Phobos
A method and system for activating thrusters of a vehicle for trajectory-tracking control of the vehicle. A transfer orbit generator to generate a transfer orbit for the vehicle from an initial orbit to a target orbit, and a feedback stabilization controller. Compute the target orbit for the vehicle about the celestial body. Compute a free trajectory with patch points along the free trajectory using a free trajectory module, each patch point includes a position and a velocity. Determine a feedback gain at each patch point using a feedback gain module, wherein a state penalty function at each patch point is set to match a state uncertainty function at the same patch point. Apply the feedback gain at each patch point to map the position and the velocity at each patch point to delta v commands, to maintain the target orbit using a feedback stabilization controller.
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.
End-to-End On-Orbit Servicing
An on-orbit servicing spacecraft includes an engagement system to engage a space vehicle or object to be serviced or tugged, so as to form a space system, and an electronic reaction control system to cause the spacecraft to rotate about roll, yaw, and pitch axes to control attitude and displacement along given trajectories to cause the spacecraft to carry out given maneuvers. The electronic reaction control system includes (i) a sensory system to directly sense physical quantities or allow physical quantities to be indirectly computed based on sensed physical quantities, including one or more of position, attitude, angular rates, available fuel, geometrical features, and on-board systems state, (ii) attitude control thrusters mounted so as to allow their positions and orientations to be adjustable, and (iii) an attitude control computer in communication with the sensory system and the attitude control thrusters and programmed to receive data from the sensory system and to control, based on the received data, positions, orientations, and operating states of the attitude control thrusters so as to control attitude and position of the spacecraft. The attitude control computer is programmed to cause the spacecraft to carry out a given mission including an engagement step, in which the engagement system and the attitude control thrusters are controlled by the attitude control computer to engage a space vehicle or object to be serviced or tugged, and one or more operating steps, in each of which the attitude control thrusters are controlled by the attitude control computer to meet one or more requirements established for the operating step.
ORBITAL ATTITUDE CONTROL DEVICE, SATELLITE, ORBITAL ATTITUDE CONTROL METHOD, AND RECORDING MEDIUM
In an orbital attitude control device (1150), an ideal thrust axis direction calculator (1505) calculates an ideal thrust axis direction based on information of a predetermined orbit, an ideal attitude calculator (1506) calculates an ideal attitude of the satellite based on the ideal thrust axis direction and a solar direction, and a control torque calculator (1510) calculates an ideal control torque that makes the attitude of the satellite follow the ideal attitude and a torque restraint plane in which the solar direction is orthogonal to a rotational axis of the solar array panel, defines an evaluation function obtained by weighting a distance from the ideal control torque and a distance from the torque restraint plane and then summing the weighted distances, and calculates the control torque that allows the drive constraint to be satisfied and the evaluation function to be minimized.
METHOD AND DEVICE FOR DEORBITING AN ARTIFICIAL SATELLITE FROM EARTH ORBIT
A method and a device for deorbiting artificial satellites from Earth orbit, the artificial satellite having multilayer insulation, at least partially detaches at least one layer of the multilayer insulation from the artificial satellite. Due to detachment of the layer, the underlying satellite structure is exposed to environmental influences. This exposure accelerates the self-disintegration of the artificial satellite, and thereby reduces the mass and increases the ballistic coefficient. Splaying out the layer augments its cross-sectional area and leads due to energy reduction to a premature re-entry into Earth's atmosphere. A number of layers can be arranged here so that regardless of a rotation of the satellite, at least one surface is always directed against the aerodynamic flow.
METHOD FOR TRACKING A SPACE OBJECT USING ON-BOARD RADAR AND LIDAR SYSTEMS
The invention relates to a method of tracking a target on an orbital trajectory by a spacecraft, the method comprising an acquisition phase which comprises the steps of activating a lidar, acquiring signals from the lidar system, determining target trajectory data from the lidar signals, wherein the spacecraft is engaged on a trajectory to approach or inspect the target, which trajectory is determined based on the target trajectory data, and if the target is no longer detected, activating a short-range detection phase, comprising activation of a wide-field radar.
ATTITUDE DETERMINATION AND CONTROL SYSTEM AND METHOD THEREOF
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.
Deployable spacecraft body
A spacecraft is disclosed, comprising a deployable spacecraft body (110) comprising a plurality of sub-systems (321-324) for controlling operations of the spacecraft, and a plurality of panels (101, 102) and a plurality of hinges (112-115) each connecting adjacent ones of the plurality of panels, the hinges being arranged to permit the plurality of panels to be folded into a stowed configuration and unfolded into a deployed configuration, wherein the plurality of sub-systems are fixed to and supported by one or more of the plurality of panels. By forming the body of the spacecraft from a deployable structure, the overall size of the spacecraft can be significantly reduced in the stowed configuration. In some embodiments, a plurality of the spacecraft in the stowed configuration can be combined into a modular spacecraft assembly prior to launch, with data and power connections between the plurality of stowed spacecraft being used to transfer power from, and data to, a payload monitoring unit on the launch vehicle.