127 results about "Satellite attitude control system" patented technology

Various embodiments of the present invention include an attitude control system for use with small satellites. According to various embodiments, the system allows rapid retargeting (e.g., high slew rates) and full three-axis attitude control of small satellites using a compact actuation system. In certain embodiments, the compact actuation system includes a plurality of single-gimbaled control moment gyroscopes (SGCMG) arranged in a pyramidal configuration that are disposed within a small satellite.

A ground simulation-test system of satellite attitude based on satellite network comprises simulation test unit of parts grade, digital simulation test unit of system grade and semiphysical simulation test unit of system grade. It is featured as using simulation test unit of parts grade and digital simulation test unit of system grade to provide physical data basis for semiphysical simulation test unit of system grade. The ground simulation testing-method of satellite attitude based on satellite network is also disclosed.

The invention relates to a satellite fault prediction method based on predictive filtering and empirical mode decomposition, which belongs to the method for safe operation and fault prediction of the space satellite, and solves the problems of serious noise influence and inaccurate prediction of the fault trend in the traditional satellite fault prediction and diagnosis method. The method comprises the following specific steps: 1, estimating errors of the satellite control system through predictive filtering according to the dynamic relationship of the nonlinear attitude of the satellite, thereby obtaining a system model error; 2, carrying out empirical mode decomposition for the system model error obtained in Step 1 to obtain the IMF component and the residual component of the n-order intrinsic mode function; and 3, establishing a fault trend model related to the residual component obtained in Step 2 through time series analysis, thereby completing the prediction and detection of minor and slow-variation faults. The invention can be applied in the field of fault diagnosis of the satellite attitude control system.

The invention discloses a satellite attitude control system failure diagnosis device based on a state observer and an equivalent space and a satellite attitude control system failure diagnosis method based on the state observer and the equivalent space, which belong to the field of aerospace and aim to solve the problems of high hardware complexity, low control accuracy and low failure diagnosis algorithm effectiveness of the conventional failure diagnosis method. The method provided by the invention comprises the following steps that: 1, a failure diagnosis observer outputs a satellite triaxial angular rate residual according to output signals of an actuator and a gyro sensor; 2, an equivalent vector space description module constructs equivalent space descriptions of the gyro sensor according to the output signal of the gyro sensor, wherein an output equivalent vector p is used for judging whether the gyro sensor fails or not; and 3, a failure diagnosis and isolation module outputs a failure separation result indicating that the actuator or the gyro sensor fails according to the satellite triaxial angular rate residual obtained by the step 1 and the equivalent vector p obtained by the step 2, and further judges which axis of the failing part fails.

The invention provides an electromagnetic formation satellite attitude and track relative control method. The method comprises the following steps: 1, attitude dynamics equations are built; 2, according to the attitude dynamics equation in a linear form with quaternion representation built in the first step, an attitude dynamics equation in a body coordinate system and a rigid satellite dynamics equation, a satellite attitude control system feedback control law is designed and obtained; and 3, according to the feedback control law obtained in the second step, relative control is carried out on the electromagnetic formation satellite attitude and the track. The method of the invention has the advantages that the attitude dynamics equations, a relative motion dynamics equation and electromagnetic force and electromagnetic torque models are built, the designed satellite attitude control system feedback control law, a flywheel angular momentum magnetic unloading algorithm, a large angle attitude maneuver method, an electromagnetic formation flying satellite motion controller and a magnetic dipole control distribution method can have good working performance, and high-efficiency relative control on the electromagnetic formation satellite attitude and the track can be realized.

The invention provides a method for performance evaluation of a spacecraft attitude control ground simulation system. According to the method, the credibility of a dynamic system, a kinematics system, a measurement system and a control system is studied based on the simulation system credibility theory, the overall credibility of the spacecraft attitude control ground simulation system is obtained through comprehensive calculation, and then the performance of the spacecraft attitude control ground simulation system is evaluated. According to the evaluation method, the credibility of the ground simulation system and an actual satellite attitude control system is considered from all aspects, simulation data are fully utilized, and the credibility of the ground simulation system is described objectively and quantitatively; the theoretical basis is reliable, the calculation process is simple, the application range is wide, and a new idea and reference are provided for performance evaluation study of other simulation systems.

The invention discloses a system of satellite attitude control integrated simulation and an implement method. The system comprises a simulation computer and an interface expansion board; simulation application under five working modes of complete mathematical simulation, component-level semi-physical simulation, component-level semi-physical simulation, whole-spacecraft semi-physical simulation, satellite-ground united simulation and in orbit attitude visualization can be realized through the combining connection of the simulation system and tested hardware; the system integrates a number of functions in one set to reduce the repeated simulation software development work to achieve the universality and generalization of the simulation system; the visualization and operability of a simulation process is enhanced; the whole flow comparison simulation analysis from scheme design to in orbit test of the satellite attitude control system is supported.

The invention provides a sensor fault tolerance observing method for a satellite attitude control system. Firstly, the control system carries out the sensor fault detecting isolation; if a first sensor is judged to have faults according to an isolation result, a second KX observer is selected to observe; and if a second sensor is judged to have faults, a first KX observer is selected to observe. The first or second KX observer has the ensuring method that if the second or first sensor has faults, the control system is analyzed into a normal subsystem and a fault subsystem by using system feedback stable control as a target, and a low-dimension KX function observer is designed by respectively aiming at the two subsystems to combine and obtain a system KX observer with fault tolerance performance. The two parallel KX observers are designed and are fused into a controlling and switching flow; and when the partial sensor output is unreliable, the satellite attitude control system still can ensure the fault tolerance observation of system rest part observed quantity to ensure the closed loop control integrality of a failure system.

A satellite attitude and orbit control system based on satellite network is prepared for sending transfer order for obtaining information to certain assigned intelligent sensor with microprocessor through satellite network for making satellite affairs dispatch unit obtain relevant information, sending control command to certain assigned intelligent execution element by dispatch unit through satellite network after calculation, executing said control command by intelligent execution element with microprocessor in order to make satellite be moved for realizing control purpose after control command is received by said execution element.

The invention relates to an embedded VxWorks based satellite attitude and orbit control system fault simulation system and method, which adopts a host computer and a target machine technology to realize a single machine model and a failure mode. The method comprises the following steps. A fault simulation host computer runs the Matlab modeling software, establishes a fault model based on Simulink, and generates a target application under the VxWorks real-time operating system under. A fault simulation target machine, connected with the fault simulation host computer through a network, runs the VxWorks real-time operating system and the target application for fault simulation. A fault injection and instruction control machine, connected with the fault simulation target machine and a satellite mounted single-mode machine respectively for transmitting the failure mode instruction of the single-mode machine to realize the switching between the single-mode simulation serial port of the fault simulation target machine and the real single-mode serial port of the satellite mounted single-mode machine. The system and the method of the invention can carry out fault diagnosis and system reconfiguration tests to improve the fault-tolerant ability of the single-machine hardware and the attitude track working in the failure mode of the satellite attitude control system so as to ensure the safety of the satellite.

The invention discloses a low-orbit constellation GEO frequency interference avoidance method based on multiple coverage. In view of the problem that in a current low-orbit communication constellationGEO interference avoidance method, the attitude of a low-orbit satellite is periodically biased, other loads of the low-orbit satellite cannot work easily, and low-orbit satellite attitude control engineering cannot be achieved easily, GEO frequency interference avoidance is achieved through opening and closing of different low-orbit satellite beams in a low-orbit constellation, and continuity oflow-orbit constellation services is guaranteed. And meanwhile, in the whole working process of the low-orbit satellite, the satellite attitude can always keep a normal three-axis stable attitude to the ground, so that the work of other loads of the low-orbit satellite is facilitated, and the engineering realization of a satellite attitude control system is also facilitated.

The invention discloses a system of an attitude and orbit control actuator for an all-electric propulsion satellite platform. The system of the attitude and orbit control actuator for the all-electric propulsion satellite platform comprises a satellite orbit control system, a satellite attitude control system, an electric propulsion system, a control torque gyroscope system, a reaction flywheel system and a satellite measurement and feedback system. In view of the working characteristics of a GEO satellite, the system of the attitude and orbit control actuator for the all-electric propulsion satellite platform provides an actuator system which adopts the control torque gyroscope, the reaction flywheel and the electric propulsion system, and aims at providing technical assurance for orbit transfer, orbit keeping and agile maneuvering of the GEO satellite; and through cooperation of the system, the following objectives on GEO satellite that the launch and orbit quality are reduced, the launch cost is reduced, the satellite position maintains accurate, the maneuverability and agility of the satellite attitude are improved, and the service life of the satellite is prolonged are achieved.

The invention belongs to the automatic control technology field and relates to an adaptive fault tolerance control method for flexible liquid-filled satellite attitude based on a fault characteristic model. According to the method, when a system in under the condition of liquid shaking, flexible vibration and external interference, a fault tolerance controller based on the fault characteristic model is designed for performer faults. The method comprises steps that (1), the fault characteristic model is established according to a flexible liquid-filled satellite attitude kinetic equation; (2), a parameter estimation algorithm is utilized to identify a coefficient of the fault characteristic model, and a coefficient estimation value of the fault characteristic model is acquired; (3), the adaptive fault tolerance controller is designed according to the coefficient estimation value of the fault characteristic model; and (4), a control torque is acquired through the adaptive fault tolerance controller, and the control torque is applied to the satellite attitude control system to control a satellite attitude angle. Through the method, control precision before and after fault generation is guaranteed to be quite high, and the time for realizing the stable state is short.

The invention discloses a self-compensating method for a dynamic and still unbalancing disturbance moment of a satellite rotating part. The dynamic and still unbalancing disturbance moment produced by quick rotating of the rotating part on a satellite can influence the stability of the satellite and reduce the control precision of the satellite. A traditional method for eliminating a dynamic and still unbalancing disturbance moment of a rotating part comprises the steps that the rotating part is subjected to dynamic balancing, and then, active control over dynamic and still unbalancing disturbance is conducted through a satellite attitude control system. The traditional method has limitation to application of rotating parts which are large in inertia, high in rotating speed and irregular in shape. According to the self-compensating method for the dynamic and still unbalancing disturbance moment of the satellite rotating part, two small bias momentum wheels are arranged on the rotating part of the satellite, and the rotating speed of the two bias momentum wheels is set according to the on-orbit calibration result of dynamic and still unbalancing disturbance so that the dynamic and still unbalancing disturbance moment produced during rotating of the rotating part can be eliminated. The self-compensating method is simple, obvious in effect and low in cost, and engineer achieving can be facilitated.

The invention discloses a satellite attitude control system health state assessment and prediction method based on a cloud model. The method is close to the structure and function of a satellite attitude control system. The method comprises the steps of establishing a satellite attitude control system health assessment index set, then using the historical data and the current data to introduce thecloud model theory to establish a satellite attitude control system health state determination method; obtaining an objective and reasonable comprehensive health state assessment result by combiningthe importance degree weight of each index in the established index set, at the same time, knowing the possible change conditions of the health state of the satellite attitude control system, and carrying out the health state trend prediction research analysis on the basis. According to the present invention, the satellite attitude control system simulation platform is subjected to the short-termand long-term health trend prediction analysis, and an efficient method is provided for the autonomous health management of the satellites.

The invention discloses a self-adaption compensation method for uncertainty of drive signs of an actuator of a satellite attitude control system and belongs to the field of aerospace. The self-adaption compensation method comprises steps as follows: (1), modeling is performed on the uncertainty of the drive signs of the actuator, and an actuator drive sign mode set is formed; (2), different self-adaption estimators are designed respectively for different drive sign modes in the established actuator drive sign mode set, and a self-adaption estimator set is formed; (3), a self-adaption controller set is designed by means of output of the self-adaption estimator set; (4), a control switching mechanism among self-adaption controllers is designed by means of output of the self-adaption estimator set, and an appropriate self-adaption controller is selected from the self-adaption controller set to generate a control signal to drive the actuator. The self-adaption compensation method can effectively guarantee the control accuracy when the drive signs of the actuator of the satellite attitude control system are uncertain, and the system can have satisfying work quality.

The invention provides a reaction flywheel output torque measuring circuit and a measuring method thereof and relates to the field of measurement on output torque of a reaction flywheel, and solve the circuit and method provided by the invention can be used for solving the problems in measuring the output torque of the reaction flywheel in the calculation process of a dynamical model. The microprocessor of the circuit is connected to a communication interface, a counter and an integral module, and acquires a flywheel rotating speed direction signal and a 50ms pulse signal; the integral moduleacquires a flywheel rotating speed pulse signal; the counter is further connected to a crystal oscillator; and the communication interface outputs the signals of a dynamical calculation module. The method comprises the following steps of: initializing the microprocessor and the counter, wherein 50ms pulse interruption is superior to flywheel rotating speed pulse interruption; performing the 50ms pulse interruption: recording T50, setting flag to be equal to 1 and quitting the interruption; and performing the flywheel rotating speed pulse interruption: 1, adding 1 to the count value, performing a step 2 if the flag is equal to 1, otherwise, quitting the interruption; 2, reading Tflag, and calculating the rotating speed of the reaction flywheel within a current calculation cycle; 3, calculating moment; and 4, sending the moment to the dynamical model and quitting the interruption. The circuit and method disclosed by the invention are applied to dynamically testing a satellite attitude control system.