68 results about "Earth observation satellite" patented technology

A satellite autonomous orbit determination method based on satellite-borne GNSS multiple antennas. According to the method, a Kalman filter is extended; multiple GNSS antennas measured pseudorange observation values are made full use of to carry out real-time filtering correction of an orbit prediction value using a high precision mechanical model; and high precision satellite orbit information is obtained. According to the invention, the problems of the high precision orbit determination in a complex posture maneuver can be solved. In the invention, the orbit determination result is high in precision, good in stability, and highly real-time, can meet the orbit determination demand of the low orbit satellite and high precision satellite, can be widely applied to the high precision orbit determination of the space station, high resolution earth observation satellite and other space missions, and has a wide promotion and application prospect.

A satellite system includes a satellite operating in an orbit around the Earth and a satellite operating in another orbit around the Earth. The satellite points a fixed beam at least temporarily to a zone above the Earth's surface through which the satellite passes.

The invention discloses a satellite in-orbit free boundary condition simulation device. The satellite in-orbit free boundary condition simulation device mainly comprises a satellite butt joint plate, supporting springs, satellite balance adjusting devices, a limiting protecting device and a supporting plate, wherein the satellite butt joint plate at the upper portion of the device and the supporting plate at the lower portion of the device are correspondingly arranged according to the satellite mechanical structure and are generally of an annulus shape, the two ends of each supporting spring are fixedly connected to the annular portions between the satellite butt joint plate and the supporting plate respectively and evenly distributed around the annular portions so that a satellite can be elastically supported, the satellite balance adjusting devices which correspond to the supporting springs in number are fixedly arranged between the bottoms of the supporting springs and the supporting plate so that the supporting springs are supported to adjust inclination of the satellite and the simulation device caused by eccentricity of the satellite, and therefore the satellite is kept horizontal after being connected to the simulation device in a butt joint mode. According to the satellite in-orbit free boundary condition simulation device, the level of the satellite dynamics testing technique is improved, and requirements for verification of in-orbit dynamics characteristics and in-orbit micro-vibration environment tests in the process of developing satellites especially high-precision earth observation satellites are met.

The invention provides a multi-sensor-based attitude determination system, which comprises a sensitive subsystem, a signal acquisition and preprocessing subsystem and an integrated processing subsystem, wherein the sensitive subsystem integrates four classes of sensitive parts such as star sensitive probes, sun sensitive probes, fiber optic gyros and magnetic field probes; the signal acquisition and preprocessing subsystem is realized by an FPGA chip and a peripheral circuit thereof, parallelly receives output data of the four classes of sensitive probes and completes the smoothing and preprocessing of the data; and finally, the integrated processing subsystem taking a DSP (or ARM) chip as a core is utilized to realize the high-precision attitude determination of the system by an ant colony particle filter-based combined attitude determination method according to sunlight information, starlight information, inertial information and geomagnetic information after smoothing and preprocessing. The multi-sensor-based attitude determination system with high precision, integration level and reliability is realized, and has important practical significance for high-resolution earth observation of new-generation earth observation satellites.

The invention provides a method and a device for collaboratively dispatching tasks among multiple earth observation satellites. The method comprises the steps of acquiring a directed acyclic graph corresponding to an initial to-be-observed task set of each satellite, wherein the directed acyclic graph comprises the content and a time sequence connection relation of each to-be-observed task; screening out overlapping tasks through comparing the directed acyclic graph of each satellite, wherein the overlapping tasks refer to tasks with the number of executable satellites being at least more than two; predicting an execution effect of each overlapping task according to parameters of the executable satellites; acquiring actual execution satellites of each overlapping task according to the predicted execution effect; deleting the overlapping tasks of the executable satellites except for the actual execution satellites in the initial to-be-observed task set, and generating a final to-be-observed task set of the executable satellites. The embodiment of the invention improves the satellite imaging efficiency and the utilization reasonability of satellite imaging resources.

The invention provides a method for absolutely radiometric calibration of a low orbit earth observation satellite with moon as reference. The method comprises the following steps that the time during which the low orbit earth observation satellite can observe the moon is primarily determined through a satellite tool kit; the starting time of moon imaging, the ending time of moon imaging, the camera exposure time, the satellite attitude angle during imaging, the pitching angular velocity and the like are determined; according to the parameters, moon imaging is conducted, so that an image of moon is obtained; the image of the moon is analyzed through a ROLO absolutely radiometric calibration model, and absolutely radiometric calibration coefficients are obtained. By the adoption of the method, an onboard calibration device and an operating mechanism are not needed, a special ground reference source is not needed, the long-term stability of moon and the attitude maneuver capacity of the satellite are fully utilized, and the image of moon is obtained and used as a reference source.

The invention discloses a self-adaptive large neighborhood search method for AEOS (agile earth observation satellite) scheduling. The method comprises following steps: Step 1, a constraint satisfaction model of AEOS scheduling problems is established; Step 2, an initial liquid is solved and taken as a current liquid; Step 3, adjustment is performed in a neighborhood of the current liquid: a deletion operator is selected, part of masks is deleted, and a destruction liquid is obtained; an insertion operator is selected, masks are inserted into the destruction liquid, and a new liquid is obtained; Step 4, the benefit of the new liquid is calculated and compared with benefits of the current liquid and an optimal liquid, and the current liquid and the optimal liquid are updated; Step 5, operator scores are updated according to operator performance; operator weights are updated after iteration is performed preset times each time; Step 6, the optimal liquid is output if an end condition is met, otherwise, the Step 3 is executed. Aiming at the time-dependent characteristic of the AEOS scheduling problems, the constraint satisfaction model of the AEOS scheduling problems is established by adopting the maximum observation benefit as a target, a liquid framework based on self-adaptive large neighborhood search is provided, and a conflict-free scheduling scheme is generated.

The invention provides a chemical industry park environmental pollution detection method and device based on multi-source remote sensing data. The method mainly includes the steps that the multi-source remote sensing data of a detection region in a chemical industry park environment are obtained through a sensor or an earth observation satellite or others; pollution information is extracted from the multi-source remote sensing data, and whether a pollution accident happens on the detection region or not is judged according to the numerical value of the extracted pollution information and a preset pollutant judgment threshold value; according to a multi-source remote sensing image of the detection region where the pollution accident has already happened, smog floating analysis is performed on the detection region to generate a pollution accident substance diffusion model, and the position of an accident source is obtained according to the pollution accident substance diffusion model. The portable chemical industry park environmental pollution detection device integrates multi-source remote sensing data collection, pollution accident and accident source position judging, emergency processing and other functions, and rapidness, efficiency and standardization of environmental pollution sudden accident emergency rescue in a dangerous chemical industry park are achieved.

The invention relates to an earth observation satellite mission effectiveness evaluation index system and an analysis method. The system comprises a mission completion degree index, a time response degree index and a resource utilization rate index. The task fulfillment index comprises a regional target coverage rate, a total task fulfillment rate, a moving target recognition degree, a moving target tracking track fit degree, a task fulfillment benefit and a credibility of a moving target search result. The aging responsiveness index comprises a task response time and a time resolution. The resource utilization index comprises a satellite payload rate, a total satellite side swing number, a total startup time, a total startup number, a large-capacity memory occupancy rate, a ground stationand a relay satellite downlink window utilization rate. The method of the invention can fully embody the physical connection between the operation logic of the system and the indexes, and the evaluation result is intuitionistic, readable and understandable, the method of the invention is an evaluation method with practical physical significance and effectively overcomes the subjectivity and fuzziness existing universally in the efficiency evaluation process.

Provided is an anti-interference attitude control method based on the friction characteristics of a reaction wheel. To solve the problems about zero-crossing friction and low attitude control precision of a reaction wheel, the method includes the steps: establishing a spacecraft coupling kinetic equation containing the friction characteristics of the reaction wheel, designing a friction interference estimator because the reaction wheel brings friction interference, and estimating the friction of the reaction wheel in real time; designing a norminal controller to inhibit friction interference estimated errors and environment interference in a spacecraft system; and combining the norminal controller with the friction interference estimator, and designing a composite layered anti-interference controller to achieve spacecraft anti-interference attitude control under the influence of multi-source interference. According to the method, actuating mechanism dynamics are additionally applied to the spacecraft kinetic equation so as to better analyze the problem of the decreased control precision due to the characteristics of an actuating mechanism. The method can be used for high-precision attitude control over high-precision earth observation satellites, space telescopes and other spacecrafts in the aerospace field.

The invention provides an earth observation satellite task scheduling method and system. Earth observation satellite tasks include an observation task and a downloading task. The method comprises the steps of inserting the observation task and / or the downloading task in the earth observation satellite tasks according to a preset constraint condition to obtain an initial earth observation satellite task sequence; and calculating the initial earth observation satellite task sequence through a preset first algorithm to obtain an earth observation satellite task sequence after scheduling. The observation task and / or downloading task is inserted in the earth observation satellite task according to the preset constraint condition to obtain the initial earth observation satellite task sequence, and the initial earth observation satellite task sequence is optimized through the first algorithm to obtain the earth observation satellite task sequence after scheduling, so that the satellite utilization efficiency is improved.

The invention relates to a flexible spacecraft attitude control method for flywheel saturation and friction characteristics and aims to solve a problem of influence of flywheel saturation and friction characteristics on spacecraft control precision. According to the method, a spacecraft coupling kinetic equation containing flywheel saturation and friction characteristics is firstly constructed; secondly, a friction interference estimator according to flywheel friction characteristics is established; thirdly, a flexible vibration observer is designed according to interference caused by flexible accessory vibration; fourthly, an anti-saturation controller is designed for inhibition according to friction interference estimation errors and flexible vibration interference observation errors; and lastly, through solving control gain of the anti-saturation controller, the friction interference estimator and the flexible vibration observer, a composite layered anti-interference controller is designed, and spacecraft anti-interference attitude control under the action of multi-source interference influence is accomplished. The method is advantaged in that attitude control precision of spacecrafts employing a flywheel execution mechanism can be remarkably improved, and the method can be applied to high precision attitude control on spacecrafts such as high precision earth observation satellites in the aerospace field and space telescopes.

The invention provides a rapid task planning method for a multi-source earth observation satellite. The rapid task planning method comprises the following steps: performing calculating to obtain satellite ephemeris data; establishing an Index in a space-time two-dimensional mode, establishing a data structure, and storing ephemeris data in a KEY-VALUE type database; Performing discontinuous ephemeris data screening in the candidate range, performing satellite visibility calculation, and performing calculation to obtain a point target visible window; Processing the region target by adopting a greedy snake algorithm to obtain a region target visible window, and generating a meta-task window according to the region target visible window; And optimizing and arranging the meta-task window by adopting a pluggable task planning optimization and evaluation method to obtain a relatively optimal planning scheme. According to the invention, rapid access of data can be ensured, unified mode high-speed processing of common satellites and agile satellites is realized, and high-quality task planning is realized in a multi-satellite and multi-task combined planning scene.

The invention discloses a fixed star centroid extraction method used for an area array instrument of a geostationary orbit earth observation satellite. The fixed star centroid extraction method comprises the steps of: downloading and analyzing fixed star observation data of the area array instrument; preprocessing fixed star observation image sequences obtained through analysis; fusing the image sequences after removing fixed-pattern noise into a fixed star trajectory image by adopting an image sequence fusion method, and determining a fixed star trajectory region of the fixed star trajectoryimage; performing fixed star identification according to a number of fixed stars in a forecasting image surface and the determined fixed star trajectory region, and determining a fixed star region corresponding to each forecasted fixed star on each frame of image; acquiring a fixed star trajectory fitting equation by adopting a fixed star trajectory fitting method, and calculating a precise fixedstar centroid subpixel coordinate sequence; and selecting the most precise fixed star centroid subpixel coordinates from the precise fixed star centroid subpixel coordinate sequence. Compared with centroid coordinates obtained in a single frame image, the fixed star centroid subpixel coordinates determined by adopting the fixed star centroid extraction method is less affected by the noise, and thecalculation precision is higher.

The invention discloses a satellite constellation system multidisciplinary design optimization method based on an agent model, and belongs to the field of spacecraft constellation application. The method comprises the steps of on the basis of the Walker-delta constellation configuration and a small-sized earth observation satellite structure, establishing a key subject analysis model of the satellite constellation system by comprehensively considering the design requirements of the constellation configuration and a satellite subsystem; adopting a sequence radial basis function based on a support vector machine and a discrete-continuous variable sampling method and taking the satellite constellation system mass as an objective function to optimize a preselected design variable; mapping thediscrete variables in a continuous space through a discrete-continuous variable sampling method; replacing an original analysis model with an RBF agent model; identifying an interest interval by adopting an SVM (support vector machine), and performing sequence sampling in the interval to update and manage an RBF agent model, so that a design scheme which meets the requirements of constellation configuration and a satellite subsystem and has the minimum total mass of the satellite constellation system is efficiently obtained, the calculation cost of the satellite constellation system is furtherreduced, and the optimization efficiency is improved.

The invention relates to a simulation analysis method for a drift angle of an agile earth observation satellite. The simulation analysis method comprises the following steps: firstly, generating a position vector, a velocity vector and osculating orbit element of the satellite at corresponding moments by using STK software; secondly, calculating a unit vector of a camera optical axis in an equatorial inertial coordinate system based on a target rolling angle and a target pitch angle of the satellite as well as the position vector and the velocity vector obtained in the first step; thirdly, calculating a vector between the earth center and a photographing point in the equatorial inertial coordinate system based on the position vector in the first step and the unit vector of the camera optical axis obtained in the second step; fourthly, calculating the drift angle based on the results of the first step, the second step and the third step. The method disclosed by the invention can be used for analyzing and verifying the calculation accuracy of the agile earth observation satellite in a ground test.

Aiming at the feature that the spatial network has time-varying topology, for solving the challenge caused by the dynamic nature to the network routing and overcoming the defects of the distributed routing and a static diagram, the invention provides an earth observation satellite network minimum expenditure routing method based on space-time diagram, a specific construction algorithm and the minimum expenditure routing strategy of the time-space diagram are given. The time-space diagram can capture a switching point of a dynamic network and is provided with the time and space dimension information. Therefore, in comparison with other method, the routing method based on the time-space diagram can provide more accurate result and more detailed information. In consideration of the transmission task requirement of the actual spatial network, the invention designs the minimum expenditure routing (MCMP) strategy, and designs the EAMP algorithm based on the earliest arrival time as the comparison object; the experiment verifies the feasibility and advantages of the time-space diagram applied to the spatial network.

Prevented planting (PP), where wet conditions during the planting season prevent access to farmed fields, costs the United States an average of many hundreds of millions of dollars in crop losses each year. Crop insurance indemnifies most of the losses of PP on farmed land in the US. This system, method, and product uses Earth observation satellite data and geographic information system technology to provide automated PP crop-loss adjusting performed digitally to enhance crop loss adjusting efficiency, reduce loss-adjusting costs, assess crop losses across large geographic regions to forecast financial set asides to meet claim payouts, and parse data to all interested parties.

The invention relates to a high-power chip flexible interconnection module and a processing method. The invention provides a more advanced surface interconnection technology to replace traditional lead bonding, and aims to solve the problems of reduction of conductivity and bonding strength and the like caused by thermal mismatching and growth of intermetallic compounds in aluminum wire bonding and realize an interconnection technology with lower impedance value, higher thermal conductivity and longer service life. The contact area between flexible copper foil and a surface of the power chip is increased, the uniform distribution condition of heat on the surface of the chip is effectively improved, hot spots on the surface of the chip are reduced, and meanwhile, the current-carrying capacity is improved by 30% compared with that of a lead bonding process. The high-power chip low-loss flexible circuit interconnection technology is of great significance for promoting realization of deployment of a new-generation remote sensing common platform and a high-resolution earth observation satellite in the morning and promoting early application of a wide bandgap semiconductor device in an aerospace electronic product, and also providing a reference for continuous improvement of the performance of a commercial power module.

The focus of the present disclosure relates to a constellation of earth-observation satellites communicating with terrestrial access points through an intermediate satellite constellation of networked relay satellites. The network system includes one or more terrestrial access points, one or more earth observation satellites, and a satellite constellation including a plurality of communicatively coupled relay satellites. The earth observation satellites establish links with the relay satellites, which relay the communications from the earth observation satellites to the terrestrial access points. The earth observation satellite can transfer recorded information to one or more of the plurality of relay satellites. The communication from the earth observation satellite may be routed through multiple relay satellite in the network system to reach the terrestrial access point. Rather than transferring information from an earth observation satellite only when the earth observation satellite passes over the terrestrial access point, the network disclosed enables earth observation satellites to transfer information through the intermediate satellite constellation quickly and securely from nearly anywhere along its orbit around the Earth. Because the Earth observation satellite can route recorded information through the plurality of satellites in the intermediate satellite constellation to a terrestrial access point, instead of only when the earth observation satellite travels within range of a single terrestrial access point, the disclosed network system significantly extends the data transfer window while reducing monitoring delays.

A research method for multidisciplinary design optimization of a certain earth observation satellite includes the steps of 1, analyzing different disciplines which the earth observation satellite is related to, by a mathematical model layer L1, determining a design variable range, finally determining a mathematical model of the earth observation satellite, and transmitting the information of the mathematical model to an optimization model layer L2; 2, on the basis that the optimization model layer L2 already acquires the information of the mathematical model, determining an optimization target and a bound variable, establishing an optimization model, and transmitting the information of the optimization model to an algorithmic computation layer L3; 3, acquiring a group of computation results by an enveloped dual algorithm computation module of the algorithmic computation layer L3, and providing a result data layer L4 with the computation results; 4, analyzing the computation results in the result data layer L4; if the computation results meet a convergence criterion, transmitting the results to an application layer L5; if not, modifying a design variable, and repeating the steps from 1 to 4. Compared to the traditional satellite design, test, modification design and test process, the method has the advantage that efficiency is improved.

The present invention discloses an in-orbit focusing method of an earth observation satellite-borne visible light transmission camera. When an optical system of the camera defocuses to a certain extent, an image frequency domain formed by the camera has a zero point; according to a camera image out of focus, a zero point position can be found in the frequency domain; when the zero point position of the frequency domain is known, a radius of a point divergent function caused by defocusing is calculated according to the position of the zero point and a best focal plane position is estimated, and a focusing direction is determined according to the definition of an image formed by different focal plane positions, so as to determine the best focal plane position; and when the image frequency domain has no zero point, the camera is nearby the best focal plane position, the focusing adjustment direction is determined by calculating the definition of the nearby focal plane image, so as to determine the best focal plane position. Through adoption of the method, high-accuracy and efficiency of in-orbit focusing are ensured, and in-orbit imaging performance and image quality of an optical remote sensor are improved.

The invention discloses a multi-agile earth observation satellite task allocation method based on a large neighborhood search algorithm. Self-adaptive large neighborhood search of a single satellite scheduling problem is expanded to a multi-satellite scheduling problem. By defining four allocation operations, an adaptive task allocation mechanism is introduced into a large neighborhood search framework. In large neighborhood search based on adaptive task allocation, a removal operation removes a task from a current solution, an insertion operation inserts the task into the removed solution, and an allocation operation reallocates the task to different satellites if the solution is still not improved after multiple iterations. According to the method, the task allocation problem of the agile earth observation satellite group of the dynamic tasks is optimized, so that the dynamic tasks can be processed at any time in the operation process of satellites.

An architecture design and optimization system of an earth observation satellite is composed of an artificial subsystem of an earth observation satellite system, a capability evaluation subsystem of the earth observation satellite system, a comprehensive demonstration subsystem and subsystem for designing and configuring operation control strategy of earth observation satellite system. The artificial subsystem of the earth observation satellite system is the core of the earth observation satellite system structure design and optimization system. After loading of the information of the operation control strategy and the system structure, the computational experiment research is carried out, the quantitative index of the system efficiency is obtained through the system capability evaluationsubsystem, and support is provided to produce the next step optimization suggestion;. Visual display and analysis of system state variables are realized by the integrated demonstration subsystem, which supports the demonstration and evaluation of system capability. The system can be used to support the planning and evaluation of the earth observation satellite system cooperative work scheme, the analysis and evaluation of the system routine operation scheme and emergency task scheduling scheme, and the evaluation and optimization of the system configuration scheme and construction developmentscheme.

The invention discloses a multidisciplinary earth observation satellite optimization system on the basis of an enveloping dual-algorithm system, and relates to multidisciplinary earth observation satellite optimization systems of enveloping dual-algorithm systems. The multidisciplinary earth observation satellite optimization system comprises five layers including a mathematical model layer L1, an optimization model layer L2, an algorithm computation layer L3, a data layer L4 and an application layer L5; the layers are in an information transmission relation which is sequentially L1-L2-L3-L4-L5. The multidisciplinary earth observation satellite optimization system has the advantages that optimization objective-earth observation resolution and interrelated constraints are determined on the basis of earth observation satellite mathematical models, satellite optimization models are built, then satellite models are optimized and computed by enveloping dual algorithms, and the optimal earth observation resolution of satellites is acquired if optimization results meet convergence criteria; the multidisciplinary earth observation satellite optimization system also can be used for quickly computing design objectives and parameter variables of the satellites, and the efficiency can be improved as compared with the traditional process including satellite designing, testing, design modifying and testing.

The invention relates to an assessment method for in-orbit calibration precision of a directional angle system error of a satellite-borne laser altimeter. The method comprises the following steps: determining a laser alignment unit vector comprehensively considering the laser alignment and a surface normal vector corresponding to each measurement value used during in-orbit calibration of the satellite-borne laser altimeter; determining a normal matrix of in-orbit calibration of the satellite-borne laser altimeter; determining a unit weight variance of total laser foot point position offset caused by a random error during in-orbit calibration of the laser altimeter; and supporting calibration precision results in three directions of yawing, rolling and pitching when the satellite-borne laser altimeter in-orbit calibration directional angle system error is calculated, so that the in-orbit calibration precision of the laser altimeter angle system error is evaluated. According to the invention, the blank of a theoretical evaluation model of calibration precision during in-orbit calibration of a current earth observation satellite-borne laser altimeter is filled; moreover, other data does not need to be obtained additionally, and the precision of the calibration result of the laser altimeter can be evaluated while in-orbit calibration is carried out on the laser altimeter.

The invention provides a data-driven earth observation satellite power supply system emergency guarantee capability evaluation method comprising the following steps: obtaining a satellite telemetry historical data set, and preprocessing the historical data set; predicting the output power of the solar cell array in the future according to the preprocessed historical data set of the solar cell array; according to the preprocessed historical data set of the relevant parameters of the storage battery pack, calculating the energy consumption of the satellite for executing various types of tasks onorbit; constructing a storage battery pack state-of-charge simulation process according to the predicted output power of the solar battery array and various types of on-orbit task energy consumptionof the satellite; inputting a to-be-evaluated emergency task into the storage battery pack state-of-charge simulation process to obtain a storage battery pack state-of-charge prediction value; and comparing the predicted value of the state of charge of the storage battery pack with a discharge depth threshold, and giving an evaluation result. According to the invention, the satellite telemetry historical data set and the task instruction information are analyzed to obtain the guarantee evaluation result of the power supply system under the emergency task condition.

The invention provides a sun synchronous regression orbit earth observation mixed constellation design method, which comprises the following steps of: designing a plurality of earth observation satellites into a mixed constellation, and deducing the relationship between satellite track offset and phase difference by analyzing track change caused by satellite orbit motion and taking the geographic longitude difference of a satellite descending node as a variable, and therefore, according to different requirements for time resolution, observation target constraint and the like in an actual observation task, two typical mixed constellation methods of coplanar and different planes are designed, and the observation application requirement is met. According to the method, constellation design can be simply, conveniently and rapidly completed, a large amount of numerical calculation is avoided, and the difficulty and complexity of hybrid constellation design and construction work are reduced; and the hybrid constellation constructed by the method is stable in configuration, avoids frequent control, does not increase workload, does not generate extra propellant consumption, is safe and convenient, and is convenient for engineering application.