Matches 51 - 100 out of 276 < 1 2 3 4 5 6 >
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6448940 Triple reflector antenna deployment and storage systems  
An antenna deployment system for use in storing and deploying three antennas that are located on the same side of a spacecraft or other fixed body. The three antennas are nested and are stacked in...
6443398 Redundant energy storage device having momentum wheels  
The invention provides a momentum wheel energy storage device for a spacecraft or satellite. The device has six wheels whose axes of rotation are parallel to edges of a tetrahedron. It thus...
6439510 Electrical energy management and attitude control system for a satellite  
A system for managing electrical energy and for controlling attitide of a satellite has an attitude control unit which controls a plurality of reaction wheels oriented about different axes for...
6382565 Satellite spin reorientation using a single degree of freedom momentum storage device  
Methods and systems for stabilizing satellite spin about an intermediate inertia axis (Z) are disclosed. A set of gyros ( 22 ) sense the X component and the Y component of the angular velocity of...
6377352 Angular rate and reaction torque assembly  
A device for both sensing an angular rate of an object and applying an angular rotation torque to the object. The device includes a rate sensing mechanism, such as a fiber optic gyroscope, which...
6360996 Steering control for skewed scissors pair CMG clusters  
An agile steering control arrangement is provided for a spacecraft having a skewed scissor pair control moment gyro (SSP CMG) attitude control arrangement gimbaled with respect to the spacecraft...
6341750 Spacecraft motion estimation using a gimballed momentum wheel  
A method for estimating motion of a dual-spin spacecraft having a gimballed momentum wheel. The method disengages the gimbal from its drive train in anticipation of a short disturbance. Then, the...
6340138 Stationkeeping method utilizing open-loop thruster pulses and closed-loop authority limited momentum storage devices  
A Stationkeeping Mode for a spacecraft having a gimballed momentum wheel for attitude control in which the stationkeeping is divided into short duration open-loop stationkeeping maneuvers to...
6340137 Moment control unit for spacecraft attitude control  
A moment control device for positioning a spacecraft which employs a plurality of spinning bodies operable to impart a desired torque to a space craft, the bodies being constructed in a unitary...
6318676 Equatorial-normal body-stabilized spacecraft and control method for inclined orbit operation  
A control method and improved equatorial-normal body-stabilized spacecraft that operates in an inclined orbit. The control method controls pointing of payloads (communication antennas and...
6311931 Bi-directional momentum bias spacecraft attitude control  
A method and apparatus for controlling a spacecraft having a first axis is disclosed. The apparatus comprises a momentum wheel unidirectionally rotatable about a spin axis substantially co-aligned...
6311932 Yaw steering momentum system  
A continuous three axes satellite pointing system for a solar powered satellite, the system comprising a body control module for producing three orthogonal axes body control torques, a momentum...
6305647 Method and apparatus for steering the attitude of a satellite  
A method is disclosed for controlling the attitude of a satellite by controlling the speed of the gimbals of CMGs in a cluster of CMGs, the CMG having respective wheels mounted on gimbals that are...
6304799 Apparatus and method for lasercom tracking acquisition  
An apparatus for determining the pointing uncertainty of a satellite communications system comprises a communications terminal coupled to a pointing mechanism which is operative to move and...
6298288 Autonomous gyro scale factor and misalignment calibration  
A system and method of estimating the attitude of a spacecraft is disclosed. A three-axis inertial-based estimate of spacecraft attitude is produced and is compared to a stellar-based estimate of...
6296207 Combined stationkeeping and momentum management  
There is provided a method and system for simultaneous north-south stationkeeping and 3-axis momentum management for a geosynchronous orbiting spacecraft. The spacecraft has a first thruster, a...
6293501 Spacecraft momentum management system  
A momentum control system for driving the momentum of a spinning spacecraft to zero while it spins around a sunline. The system includes a sun sensor for determining the position of the sun, a...
6289268 Attitude determination system and method  
A star tracker coupled to the spacecraft having a star catalog associated therewith. A sun sensor is coupled to the spacecraft. A control processor is coupled to the star tracker and the sun...
6285928 Onboard attitude control using reaction wheels  
An onboard attitude control system is constructed to utilize a four reaction wheel system having a reference axis, wherein at least three of the reaction wheel spin axes are oriented obliquely to...
6283415 Simplified yaw steering method for satellite antenna beam control  
For an antenna on a satellite in an inclined orbit about the Earth, cross-track motion resulting from the rotation of the Earth can be reduced in antenna coordinates by yawing the antenna...
6260805 Method of controlling attitude of a momentum biased spacecraft during long-duration thruster firings  
A method is provided for controlling the attitude of a momentum biased spacecraft about all three mutually orthogonal axes during a thruster firing maneuver without separately sensing angular...
6254036 Method and apparatus for spacecraft wheel desaturation  
A method and apparatus are provided that effect spacecraft wheel desaturation by controlling the magnetic torquers aboard the spacecraft. An attitude control system energizes a magnetic torquer...
6241194 Momentum position control  
A vehicle control system is disclosed utilizing a reaction wheel assembly for producing small scanning motions and, in combination, a scissored pair of low-cost control moment gyros is used to...
6234427 Solar array regulation and spacecraft pointing using flywheel energy storage with programmable voltage control  
A satellite power regulation and pointing system is disclosed that comprises a power bus (104) and first and second flywheels (114-116) capable of storing rotational energy. Each flywheel (114-118)...
6231011 Satellite angular momentum control system using magnet-superconductor flywheels  
A torque/reactive momentum wheel control system for use in satellites for dynamic attitude maintenance and alteration where the flywheel of each momentum wheel is levitated by a high-temperature...
6196502 Attitude control of spinning spacecraft with counterspun controls platform  
The attitude of a spinning spacecraft whose spin axis is substantially in the plane of the orbit is controlled without the use of reaction control thrusters. A two-axis gimbal on which a momentum...
6191728 Agile satellite targeting  
A method is disclosed for targeting a satellite orbiting earth between to sites on earth based on an access time that is transmitted from a ground station. Control momentum gyros are used to change...
6152403 Gyroscopic calibration methods for spacecraft  
Spacecraft cost, volume and weight are reduced with gyroscope calibration methods that can be effected with structures (e.g., a single-axis Sun sensor and a wheel system) which are typically...
6152402 Dual spin zero momentum satellite system  
An attitude control system for a spacecraft which includes a bearing power and transfer assembly. The bearing power and transfer assembly is disposed between a first body and a second body. The...
6154691 Orienting a satellite with controlled momentum gyros  
Controlled momentum gyros are rotated to change the attitude of a satellite as rapidly as possible by rotating them along a great circle path on an imaginary spherical surface around the satellite....
6141606 Wheel speed control system for spacecraft with rejection of null space wheel momentum  
A spacecraft attitude control system uses at least four reaction wheels In order to minimize reaction wheel speed and therefore power, a wheel speed control means system is provided. The wheel...
6138953 Slew rate direction determination for acquisition maneuvers using reaction wheels  
Autonomous slewing of a spacecraft about a desired axis using reaction wheels permits a maximum slew rate without wheel saturation even with one wheel failure. The slew is carried out if the total...
6138952 Transient free actuator switching  
An automatic apparatus and method that is used to switch actuators, such as momentum wheels, used on a spacecraft without impacting the pointing performance of the spacecraft. The apparatus and...
6135392 Spacecraft attitude control actuator and method  
A spacecraft attitude control system includes a Momentum Wheel Assembly (MWA) or a Reaction Wheel Assembly (RWA), containing a spinning flywheel, mounted by the use of a mounting bracket to a...
6138061 Onboard orbit propagation using quaternions  
A method for controlling orbiting spacecraft uploads a plurality of parameters to an onboard processor, the parameters including a plurality of quaternion elements describing an inertial to orbit...
6131068 Accuracy of an inertial measurement unit  
A missile guidance system employs a strap down inertial measurement unit with a separate accelerometer and star sensor that are moved for preflight accelerometer initialization. During flight,...
6131056 Continuous attitude control that avoids CMG array singularities  
A system for avoiding singularities in a control moment gyro (CMG) array of a satellite uses closed and open loop control of the CMGs for reorientation of the satellite. A control system detects...
6128556 CMG control based on angular momentum to control satellite attitude  
Control moment gyros in an array are rotated to reorient a satellite. Gyro angle is selected from one of three values based upon whether the stored angular momentum for the desired angle is below a...
6113033 Combined flywheel energy storage and attitude control apparatus for spacecraft  
An apparatus for storing energy and actuating the attitude of a spacecraft includes a first gimbaled flywheel assembly having a first rotor rotating in a first direction, and a second gimbaled...
6108593 Method and apparatus for estimating attitude sensor bias in a satellite  
A method and apparatus for estimating attitude sensor bias in a satellite system uses attitude sensors and a spacecraft control processor. Attitude sensors provide output signals, which may contain...
6107770 Control system for counter-oscillating masses  
A control system stabilizes the flexible body bending modes of a space, airborne, or ground-based system, while providing angular position control of an oscillating mass connected to a...
6089508 Autonomous spacecraft safing with reaction wheels  
A spacecraft with a reaction wheel system can be autonomously safed by setting the solar wings to continuous tracking, determining a slew rate vector based on the total angular momentum, and...
6076772 Methods for controlling spacecraft attitudes without exciting spacecraft resonances  
Attitude-control methods are provided which eliminate or reduce structural resonances in spacecraft that are excited by momentum wheel imperfections. The methods are preferably practiced with an...
6076773 Spin-stabilized spacecraft and methods  
Spin-stabilized spacecraft are provided which facilitate simple attitude maneuvers and the use of high-gain antennas and efficient solar panels without the need for complex control systems and an...
6062512 Wobble and nutation control, and spin stabilization for a spacecraft using momentum conserving devices  
A method of damping nutation and removing wobble of a spacecraft provided with first and second momentum sources having linearly independent momentum components in the plane transverse to the given...
6047927 Escaping singularities in a satellite attitude control  
Control moment gyros in an array are rotated to reorient a satellite by an attitude signal. If the signal causes a gyro to have position that will produce a singularity in attitude control, a...
6047226 Enhanced stellar attitude determination system  
Spacecraft attitude is efficiently controlled by utilizing spatial noise and temporal noise in the calculation of gains to a Kalman filter. Spatial noise is modeled in a dynamic fashion so as to...
6042240 Adjustable three dimensional focal length tracking reflector array  
A reflector for focusing sunlight upon a single location. The reflector is preferably positioned in orbit about a celestial body to focus sunlight on objects such as space debris to heat up and...
6042058 Stationkeeping and momentum-dumping thruster systems and methods  
Spacecraft stationkeeping and momentum-dumping methods are facilitated by the use of selected diagonal pairs of thrusters which are positioned adjacent to nadir or antinadir spacecraft faces. The...
6039290 Robust singularity avoidance in satellite attitude control  
Control moment gyros in an array are rotated to reorient a satellite. A pseudo inverse control is employed that adds a term to a Moore-Penrose pseudo inverse to prevent a singularity.
Matches 51 - 100 out of 276 < 1 2 3 4 5 6 >