Constellation Inspection Orbit Design and Visualization System and Method Based on the Interconnection of STK and MATLAB

Abstract

The present invention discloses a constellation inspection orbit design and visualization system and method based on the interconnection of STK and MATLAB. The system integrates the STKX component in the form of an ActiveX control and displays it on the GUI interface through Matlab. By utilizing the rich secondary development interfaces and good display functions of STK, it realizes the analysis and display of function modules such as constellation orbit deployment query, fly-around orbit design and orbit maintenance, and fly-by orbit design. The present invention can achieve the simulation analysis of constellation inspection orbit design, and has important practical value for the visualization of constellation inspection orbit design.

Description

Technical Field

[0001] The present invention belongs to the technical field of visual simulation, and particularly relates to a constellation inspection orbit design and visualization system and method based on the interconnection of STK and MATLAB. Background Art

[0002] With the rapid development of space technology, space launch missions are becoming increasingly frequent. Especially with the concept of constellations proposed, multiple satellites can be deployed through a single launch mission. Subsequently, space debris has also increased, leading to an increasingly complex space environment. Therefore, a reliable visualization method for constellation inspection orbit design is required to regularly inspect constellations to ensure that constellations can operate in a safe environment.

[0003] Currently, regarding the problem of visualization methods for constellation inspection orbit design, there are many tools and software at home and abroad, which can be roughly summarized into three categories: The first category is commercial software, such as STK (Satellite Tool Kit) and GMAT (General Mission Analysis Tool). STK is a comprehensive simulation and analysis software developed by AGI Corporation, widely used in the fields of aerospace, national defense, communication, etc. It can simulate and analyze various complex systems, including satellite orbits, sensor coverage, communication links, etc., and provides three-dimensional and two-dimensional visualization modules for analysis and calculation display. GMAT is an open-source software developed by NASA, with functions similar to STK. This method is difficult to achieve calculation analysis and display for specific tasks. The second category is to use programming software for calculation analysis and display. MATLAB, which is widely used in the field of calculation analysis, is a commercial mathematical software produced by MathWorks in the United States. It has powerful numerical calculation and algorithm processing capabilities, and its built-in rich toolboxes have powerful visualization functions, widely used in data analysis, wireless communication, deep learning, image processing and computer vision, signal processing, quantitative finance and risk management, robotics, control systems, etc. This method has high costs and low efficiency. The third category is to develop special software for specific space missions. This method has high costs and is not widely applicable. Summary of the Invention

[0004] The purpose of the present invention is to provide a constellation inspection orbit design and visualization system and method based on the interconnection of STK and MATLAB for the problems existing in the above-mentioned prior art.

[0005] The technical solution for achieving the object of the present invention is as follows: On the one hand, a constellation inspection orbit design and visualization system based on the interconnection of STK and MATLAB is provided. The system integrates and displays the STKX component in the form of an ActiveX control through Matlab on the GUI interface, and uses STK to implement the analysis and display of the constellation orbit deployment query, fly-around orbit design and orbit maintenance, and fly-by orbit design function modules.

[0006] Further, the system includes a main interface, an orbit deployment query module, a fly-around orbit design and orbit maintenance module, and a fly-by orbit design module;

[0007] The main interface is used to display the 2D / 3D scene display of the constellation satellite classification based on the STKX component, and is used to provide the entry ports for each module;

[0008] The orbit deployment query module is used to display the deployment situation of each orbit plane of the constellation;

[0009] The fly-around orbit design and orbit maintenance module is used to implement the fly-around orbit design for the constellation satellite inspection required and the orbit maintenance fuel consumption calculation, and evaluate the orbit maintenance effect;

[0010] The fly-by orbit design module is used to implement the fly-by orbit design for the constellation satellite inspection required for any orbit plane, and display the fly-by monitoring effect.

[0011] Further, the fly-around orbit design and orbit maintenance module outputs the fly-around orbit design result through the fly-around orbit design algorithm;

[0012] The fly-around orbit design algorithm is based on the CW equation and designs the fly-around orbit according to the load function requirements. Specifically, it includes:

[0013] Step 3.1, set the input parameters, including the target star, simulation time, fly-around radius, threshold, and control period; send a query request to the STK engine according to the input target star name, obtain the target star handle, combine the six orbital elements of the target orbit read out, calculate the absolute orbit information of the fly-around star, and send a satellite creation request to the STK engine to establish a fly-around star object;

[0014] Step 3.2, in the natural drift stage, when the main star orbit is a nearly circular orbit, through theoretical derivation, obtain the polar coordinate form of the amplitude-phase of the CW equation:

[0015]

[0016] In the formula, x(t), y(t), z(t), are the relative position vector and relative velocity vector of the fly-around star at time t, n is the average angular velocity of the target star, rx and r z are the amplitudes of radial and normal motions, respectively, and l x and l y are the deviation values of the centers of radial and track motions, respectively, and α x and α z are the initial phases of radial and normal directions, respectively;

[0017] Among them, x 0 、y 0 、z 0 , are the relative position vector and relative velocity vector of the fly-around satellite at the initial moment;

[0018] Considering the symmetry of the configuration and the fly-around radius r, the design constraints of the fly-around orbit are obtained:

[0019]

[0020] Step 3.3: According to the input target star name, query the STK engine, read the six orbital elements of the target star, calculate the average orbital angular velocity, and then calculate the relative orbital position and velocity vector parameters of the fly-around satellite according to the method in Step 3.2;

[0021] Step 3.4: Convert the fly-around satellite from the relative coordinate system to the absolute coordinate system.

[0022] Furthermore, the fly-around orbit design and orbit maintenance module maintains the fuel consumption through an orbit maintenance algorithm; the orbit maintenance algorithm specifically includes:

[0023] Step 4.1: According to the input control period, threshold, and simulation time, calculate the number of maintenance times during the analysis period, call the orbit prediction module of the STK engine to obtain the orbit data of the target star and the fly-around satellite during the analysis period, and convert the absolute orbital elements of the fly-around satellite into ROE parameters according to the coordinate transformation relationship;

[0024] Step 4.2: The control strategy is as follows: alternate between the natural drift stage and the controlled flight stage. After the fly-around satellite flies for a natural flight cycle, calculate the deviation from the reference orbit, perform orbit correction within the control period, and calculate the magnitudes and action times of the tangential and normal pulses according to the pulse analytical solution;

[0025] Step 4.3: Store the orbit data of the fly-around satellite under the two conditions of natural drift and orbit maintenance, and repeat the above Steps 4.1 to 4.2 until the time exceeds the analysis period;

[0026] Step 4.4: Plot the trajectory of the fly-around satellite and display the orbital elements and pulse magnitudes of the fly-around satellite.

[0027] Furthermore, step 4.2 specifically includes: decoupling the orbit maintenance problem into out-of-plane vector correction and in-plane orbit correction based on relative dynamic characteristics;

[0028] The influence of the impulse on the relative orbital elements is shown in the following formula:

[0029]

[0030] In the formula, a is the semi-major axis of the reference orbit, Δδα k represents the configuration parameter, u k represents the mean argument of latitude of the reference orbit at the time of impulse application, δv R , δv T and δv N represent the radial impulse, the along-track impulse, and the normal impulse, respectively;

[0031] (1) The in-plane orbit correction is performed using three tangential impulses, and its control solution is:

[0032]

[0033] In the formula, T is the orbital period of the fly-around satellite, δa, δe, and δλ are the relative semi-major axis, relative eccentricity, and relative argument of longitude of the orbit, respectively, δa man , δe man and δλ man are the configuration offset target parameters, δv t1 , δv t2 and δv t3 are the magnitudes of the three tangential impulses, respectively;

[0034] The argument of latitude u M1 , u M2 and u M3 corresponding to the three tangential impulse maneuvers are as follows:

[0035]

[0036] In the formula, are the components of δe man respectively, δe x , δe y are the components of δe, respectively;

[0037] (2) The out-of-plane vector correction is performed using a single normal impulse δv n for correction, and its control solution is:

[0038]

[0039] In the formula, Δδi x is the component of the relative orbital inclination Δδi;

[0040] The latitude argument u corresponding to the normal pulse n as follows:

[0041]

[0042] In the formula, Δδi x , Δδi y is the component of the relative orbital inclination Δδi;

[0043] Furthermore, the configuration bias target parameter δa man ,δe man They are:

[0044] δa man =-7γsin(2i)Δδi x

[0045]

[0046]

[0047] In the formula, Δδi x is the component of the relative orbital inclination Δδi, i is the orbital inclination, γ is a constant coefficient, and is the nominal relative eccentricity δe nom The weight, To maintain the maximum allowable divergence of the relative eccentricity vector angle, δe max is the maximum allowed divergence of the relative eccentricity, is the phase angle of the E vector The differential of the latitude argument u of the formation main star.

[0048] Furthermore, the flyby trajectory design module obtains the optimal flyby trajectory through a flyby algorithm and outputs flyby trajectory design parameters; the flyby algorithm includes:

[0049] Step 7.1, set the input parameters, including the target satellite, payload range, payload angle, total simulation time and orbit recursion interval information;

[0050] Step 7.2, obtain the target satellite handle from the STK engine according to the input target satellite, initiate a data request for the target satellite inertial coordinate position and six orbital elements to the STK engine, and obtain the inertial coordinate position and six orbital elements of the target satellite at the total simulation time and discrete time input by the user;

[0051] Step 7.3, based on the six numbers of the flyby orbit designed by absolute state recursion, directly initiate a satellite creation request to the STK engine to create a flyby satellite object;

[0052] Step 7.4: The acting direction of the flyby satellite payload is opposite to the direction of the satellite pointing to the center of the earth, and the attitude is maintained with three-axis stability. The orbit prediction parameters of the target satellite group are output through the STK engine and transmitted to the GUI back-end program. For the longest flyby mission, a discrete recurrence model is adopted to predict the orbit of the flyby satellite to determine the flyby point, flyby time, and flyby angle.

[0053] Step 7.5: According to the STK orbit prediction value of the target satellite and the flyby orbit prediction value obtained through Step 7.4, a distance constraint function and an angle constraint function are constructed as the objective function of the particle swarm optimization algorithm.

[0054] Step 7.6: Based on the objective function, with the six orbital elements of the flyby satellite as the optimization variables, the particle swarm algorithm is used to optimize the flyby orbit with the longest inspection time for the orbital plane, that is, the optimal flyby orbit, and calculate and output the flyby duration for each target satellite.

[0055] Further, the discrete recurrence model in Step 7.4 is specifically:

[0056] Let the sampling frequency be T'. When the time t satisfies kT' ≤ t ≤ (k + 1)T', where k is any positive constant, the state variable is denoted as The discrete state equation of the object sampled by the zero-order hold, that is, the discrete recurrence model, is:

[0057]

[0058] The discrete recurrence model is converted into a simplified form:

[0059]

[0060] In the formula, A represents the state transition matrix, B represents the control matrix, u represents the control acceleration, δx, δy, δz are the components of the relative position vector δr, are the components of the relative velocity vector δv, X[(k + 1)T′], X(kT'), X(k + 1), and X(k) are the state variables corresponding to the times (k + 1)T', kT', k + 1, and k respectively;

[0061] For a linear time-invariant continuous-time system, the expression of the discrete equation obtained by solving is as shown in the following formula:

[0062]

[0063] In the formula,

[0064] Among them, S nT′ represents sin(nT′), CnT′ It represents cos(nT'), where n is the average angular velocity of the target star.

[0065] Furthermore, in step 7.5, the objective function is:

[0066] ||r skim -r target || 2 ≤D

[0067]

[0068] where r skim and r target are respectively the STK orbit prediction value of the target satellite and the flyby orbit prediction value obtained through step 7.4, and D and E are respectively the distance constraint and the angle constraint.

[0069] In one embodiment, a visualization method for a constellation inspection orbit design and visualization system based on the interconnection of STK and MATLAB is provided. The method includes:

[0070] Step 1, in the satellite tracking effectiveness evaluation, establish a scenario according to the analysis period and the ephemeris file of the constellation, trigger the data update and maintenance component, construct a classification criterion based on three orbital characteristic parameters: orbital inclination, orbital semi-major axis, and right ascension of the ascending node, and update the constellation classification data.

[0071] Step 2, operate various view components in the main interface, and combine the scenario established in step 1 to achieve 2D / 3D display of the scenario.

[0072] Step 3, trigger the orbit deployment query module, combine the scenario established in step 1 and the constellation classification result, and display the orbit information of the constellation on the text information bar through the selection of the menu bar.

[0073] Step 4, trigger the flyby orbit design and orbit maintenance module, combine the scenario established in step 1 and the constellation classification result, input the longitude and latitude of the ground target, ground station payload parameters, target star, flyby radius, time step, start and end times of the simulation, control period, and threshold parameters into the system, and output the flyby orbit design result and maintenance fuel consumption through the flyby orbit design algorithm and orbit maintenance algorithm, and dynamically display the flyby trajectory and maintenance effect.

[0074] Step 5, trigger the flyby orbit design module, combine the scenario established in step 1 and the constellation classification result, obtain the target orbital plane, flyby orbit altitude, payload action range, payload action angle, and total simulation duration information through interface interaction, obtain the optimal flyby orbit through the flyby algorithm, output the flyby orbit design parameters, and display the flyby effect.

[0075] Compared with the prior art, the remarkable advantages of the present invention are:

[0076] (1) The present invention classifies constellation satellites for the first time according to the orbital altitude and orbital inclination. On this basis, the constellation satellites are classified for the second time according to the right ascension of the ascending node, and the "shell - orbital plane - satellite" structure data is obtained. By classifying the constellation satellites, the management of the constellation system is made more efficient.

[0077] (2) The present invention uses the design algorithm and maintenance algorithm of the fly - around orbit to calculate the pulse size. By adjusting parameters, multiple reference trajectories are given, expanding the reference range of the inspection fly - around orbit for the target star.

[0078] (3) The present invention uses the particle swarm optimization algorithm to obtain the optimal grazing - fly orbit with the longest inspection time for any orbital plane under the conditions of satisfying the load action distance and load action angle parameters input by the user.

[0079] (4) The present invention combines the powerful 3D view simulation ability of STK with the powerful calculation and analysis ability of MATLAB through the interconnection of STK and MATLAB, solves the problems of structured management of constellation satellites, the design of fly - around orbits and grazing - fly orbits for constellation inspection, and provides a reference for the design of constellation inspection orbits.

[0080] The present invention will be further described in detail below with reference to the accompanying drawings. Description of the Drawings

[0081] Figure 1 It is a principle block diagram of a constellation inspection orbit design and visualization system based on the interconnection of STK and MATLAB in an embodiment.

[0082] Figure 2 It is a working flow chart of a constellation inspection orbit design and visualization system based on the interconnection of STK and MATLAB in an embodiment.

[0083] Figure 3 It is a flow chart of the particle swarm optimization algorithm. Detailed Embodiments

[0084] In order to make the purpose, technical solutions and advantages of the present application more clear, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0085] It should be noted that if there are directional indications (such as up, down, left, right, front, back...) involved in the embodiments of the present invention, the directional indications are only used to explain the relative position relationship and movement conditions between components in a specific posture (as shown in the drawings). If the specific posture changes, the directional indications will also change accordingly.

[0086] In addition, if there are descriptions such as "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and should not be construed as indicating or implying their relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between various embodiments may be combined with each other, but it must be based on the ability of those of ordinary skill in the art to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0087] In one embodiment, a constellation inspection orbit design and visualization system based on the interconnection of STK and MATLAB is provided. The system integrates and displays the STKX component in the form of an ActiveX control in the GUI interface through Matlab, and uses STK to implement the analysis and display of functions such as constellation orbit deployment query, fly-around orbit design and orbit maintenance, and fly-by orbit design.

[0088] It should be noted here that it is not limited to implementing on the MATLAB platform.

[0089] Further, in one of the embodiments, the system includes a main interface, an orbit deployment query module, a fly-around orbit design and orbit maintenance module, and a fly-by orbit design module;

[0090] The main interface is used to display the 2D / 3D scene display of constellation satellite classification based on the STKX component, and is used to provide access ports for each module;

[0091] The orbit deployment query module is used to display the deployment situation of each orbit plane of the constellation;

[0092] The fly-around orbit design and orbit maintenance module is used to implement the fly-around orbit design for the inspection of the required constellation satellites (providing a reference orbit for the fly-around inspection of the target satellite) and the calculation of orbit maintenance fuel consumption, and to evaluate the orbit maintenance effect;

[0093] The fly-by orbit design module is used to implement the fly-by orbit design for the inspection of the required constellation satellites on any orbit plane, select the fly-by orbit with the longest inspection time through the particle swarm optimization algorithm, and display the fly-by monitoring effect.

[0094] Further, in one of the embodiments, before the orbit deployment query module, the system further includes:

[0095] The constellation satellite classification module is used to classify the constellation satellites according to "shell layer - orbit plane - satellite" for convenient management and target selection. After selecting the shell layer - orbit plane, the satellite trajectory can be displayed in the 2D / 3D scene of the main interface.

[0096] Preferably, in some embodiments, the constellation classification algorithm includes: constructing a classification criterion based on three orbital characteristic parameters, namely the orbital inclination, the semi-major axis of the orbit, and the right ascension of the ascending node, to form a "shell - orbital plane - satellite" file structure.

[0097] Specifically: perform the first - stage orbital classification based on the orbital altitude and orbital inclination, divide the orbital data of the constellation according to the shell attributes, perform a secondary classification on the data under each shell based on the right ascension of the ascending node, and calculate the threshold of the right ascension of the ascending node corresponding to each shell according to the number of orbital planes in the constellation structure design parameters. Among the shell classification results, select a satellite, read its right ascension of the ascending node and compare it with that of the other satellites under the same shell. If the right ascension of the other satellites falls within the interval generated by the threshold, it is considered that these satellites are in the same orbital plane. After saving the data of the satellites in this orbital plane and deleting them from the shell data, generate new shell data. Repeat the above process until there is no target in all shell data, then output the second - stage classification result, and store the classified data according to the "shell - orbital plane - satellite" file structure.

[0098] Furthermore, in one of the embodiments, the fly - around orbit design and orbit maintenance module outputs the fly - around orbit design result through the fly - around orbit design algorithm;

[0099] The fly - around orbit design algorithm designs the fly - around orbit based on the CW equation according to the payload function requirements, specifically including:

[0100] Step 3.1, set the input parameters, including the target star, simulation time, fly - around radius, threshold, and control period; send a query request to the STK engine according to the input target star name to obtain the target star handle, calculate the absolute orbital information of the fly - around star in combination with the six orbital elements read out, and send a satellite creation request to the STK engine to establish a fly - around star object;

[0101] Step 3.2, in the natural drift stage, when the orbit of the main star is a nearly circular orbit, through theoretical derivation, obtain the polar - coordinate form of the amplitude - phase of the CW equation:

[0102]

[0103] In the formula, x(t), y(t), z(t), are the relative position vector and relative velocity vector of the fly - around star at time t respectively, n is the average angular velocity of the target star, r x and r z are the amplitudes of the radial and normal motions respectively, l x and l y are the deviations of the radial and track motions from the center respectively, α x and αz are the initial radial and normal phases respectively;

[0104] Among them, x 0 , y 0 , z 0 , are the relative position vector and relative velocity vector of the fly-around satellite at the initial moment respectively;

[0105] Considering the symmetry of the configuration and the fly-around radius r, the design constraints of the fly-around orbit are obtained:

[0106]

[0107] Step 3.3: According to the input target star name, query the STK engine, read the six orbital elements of the target star and calculate the average orbital angular velocity, and then calculate the relative orbital position and velocity vector parameters of the fly-around satellite according to the method in Step 3.2;

[0108] Step 3.4: Convert the fly-around satellite from the relative coordinate system to the absolute coordinate system.

[0109] Furthermore, in one embodiment, the fly-around orbit design and orbit maintenance module maintains the fuel consumption through an orbit maintenance algorithm; the orbit maintenance algorithm specifically includes:

[0110] Step 4.1: According to the input control period, threshold and simulation time, calculate the number of maintenance times during the analysis period, call the orbit prediction module of the STK engine to obtain the orbit data of the target star and the fly-around satellite during the analysis period, and convert the absolute orbital elements of the fly-around satellite into ROE parameters according to the coordinate transformation relationship;

[0111] Step 4.2: The control strategy is as follows: the natural drift stage and the controlled flight stage alternate. After the fly-around satellite flies for a natural flight cycle, calculate the deviation from the reference orbit, and perform orbit correction within the control period. According to the pulse analytical solution, calculate the magnitudes and action times of the tangential pulse and the normal pulse;

[0112] Step 4.3: Store the orbit data of the fly-around satellite under the two conditions of natural drift and orbit maintenance, and repeat the above steps 4.1 to 4.2 until the time exceeds the analysis period;

[0113] Step 4.4: Plot the trajectory of the fly-around satellite and display the orbital elements and pulse magnitudes of the fly-around satellite.

[0114] Furthermore, in one embodiment, Step 4.2 specifically includes: decoupling the orbit maintenance problem into out-of-plane vector correction and in-plane orbit correction according to the relative dynamic characteristics;

[0115] The influence of the pulse on the relative orbital elements is shown in the following formula:

[0116]

[0117] In the formula, a is the semi-major axis of the reference orbit, Δδα k represents the configuration parameter, u k represents the mean argument of latitude of the reference orbit at the time of pulse implementation, δv R , δv T and δv N represent the radial pulse, the in-track pulse, and the normal pulse, respectively;

[0118] (1) The in-plane orbit correction is carried out by three tangential pulses, and its control solution is:

[0119]

[0120] In the formula, T is the orbital period of the fly-around satellite, δa, δe, and δλ are the relative semi-major axis, the relative eccentricity, and the relative argument of longitude of the orbit, respectively, δa man , δe man and δλ man are the configuration offset target parameters, δv t1 , δv t2 and δv t3 are the magnitudes of the three tangential pulses, respectively;

[0121] The argument of latitude u M1 , u M2 and u M3 corresponding to the three tangential pulse maneuvers are as follows:

[0122]

[0123] In the formula, are the components of δe man respectively, and δe x , δe y are the components of δe, respectively;

[0124] (2) The out-of-plane vector correction is carried out by a single normal pulse δv n , and its control solution is:

[0125]

[0126] In the formula, Δδi x is the component of the relative orbital inclination Δδi;

[0127] The argument of latitude u n corresponding to the normal pulse is as follows:

[0128]

[0129] In the formula, Δδi x , Δδi y is the component of the relative orbital inclination Δδi;

[0130] In some embodiments, the configuration bias target parameter δa man ,δe man They are:

[0131] δa man =-7γsin(2i)Δδi x

[0132]

[0133] In the formula, Δδi x is the component of the relative orbital inclination Δδii, i is the orbital inclination, γ is a constant coefficient, and is the nominal relative eccentricity δe nom The weight, To maintain the maximum allowable divergence of the relative eccentricity vector angle, δe max is the maximum allowed divergence of the relative eccentricity, is the phase angle of the E vector The differential of the latitude argument u of the formation main star.

[0134] Furthermore, in one embodiment, the flyby trajectory design module obtains the optimal flyby trajectory through a flyby algorithm and outputs flyby trajectory design parameters; the flyby algorithm includes:

[0135] Step 7.1, set the input parameters, including the target satellite, payload range, payload angle, total simulation time and orbit recursion interval information;

[0136] Step 7.2, obtain the target satellite handle from the STK engine according to the input target satellite, initiate a data request for the target satellite inertial coordinate position and six orbital elements to the STK engine, and obtain the inertial coordinate position and six orbital elements of the target satellite at the total simulation time and discrete time input by the user;

[0137] Step 7.3, based on the six numbers of the flyby orbit designed by absolute state recursion, directly initiate a satellite creation request to the STK engine to create a flyby satellite object;

[0138] Step 7.4, the acting direction of the fly-by satellite payload is opposite to the direction of the satellite pointing to the center of the earth, and the attitude maintains three-axis stability; the orbit prediction parameters of the target satellite group are output through the STK engine and transmitted to the GUI back-end program; for the longest fly-by mission, a discrete recurrence model is adopted to predict the orbit of the fly-by satellite to determine the fly-by point, fly-by time, and fly-by angle;

[0139] Step 7.5, according to the STK orbit prediction value of the target satellite and the fly-by orbit prediction value obtained through Step 7.4, construct a distance constraint function and an angle constraint function as the objective function of the particle swarm optimization algorithm;

[0140] Step 7.6, based on the objective function, with the six orbital elements of the fly-by satellite orbit as the optimization variables, use the particle swarm algorithm to optimize the fly-by orbit with the longest inspection time for the orbital plane, that is, the optimal fly-by orbit (as shown in the flow chart of the particle swarm optimization algorithm in Figure 3 ), and calculate and output the fly-by duration for each target star.

[0141] In some embodiments, the discrete recurrence model in Step 7.4 is specifically:

[0142] Let the sampling frequency be T′. When the time t satisfies kT'≤t≤(k + 1)T', where k is any positive constant, the state variable is denoted as The discrete state equation of the object sampled by the zero-order hold, that is, the discrete recurrence model, is:

[0143]

[0144] Convert the discrete recurrence model into a simplified form:

[0145]

[0146] In the formula, A represents the state transition matrix, B represents the control matrix, u represents the control acceleration, δx, δy, δz are the components of the relative position vector δr, are the components of the relative velocity vector δv, X[(k + 1)T′], X(kT'), X(k + 1), X(k) are the state variables corresponding to the times (k + 1)T', kT', k + 1, k respectively;

[0147] For a linear time-invariant continuous-time system, the expression of the solved discrete equation is as shown in the following formula:

[0148]

[0149] In the formula,

[0150] Among them, SnT′ represents sin(nT′), C nT′ represents cos(nT'), where n is the average angular velocity of the target star.

[0151] In some embodiments, the objective function in step 7.5 is:

[0152] ||r skim -r target || 2 ≤D

[0153]

[0154] where r skim and r target are the STK orbit prediction values of the target satellite and the flyby orbit prediction values obtained through step 7.4 respectively, and D and E are the distance constraint and the angle constraint respectively.

[0155] Here, the difference between the flyby orbit prediction value r skim (x, y, z) obtained by this method and the STK orbit prediction value r target (x n , y n , z n ) of the target satellite can be used to determine whether the relative distance between the two satellites satisfies the distance constraint D at discrete time points, which is used as one of the objective functions of the particle swarm optimization algorithm. At the same time, through the vector calculation method, the angle constraint E in this process can be solved and used as the second objective function of the particle swarm optimization algorithm.

[0156] Figure 2 is the system working flow chart of the present invention. First, select whether to perform data maintenance. If data maintenance is selected, a new scene is created. Otherwise, select whether to create a new scene. If a new scene is not created, the scene is loaded. After entering the scene, select the function module. Whether to select the orbit deployment query module. If the orbit deployment query module is selected, select the shell layer, select the orbital plane, and finally display the result; otherwise, select whether to perform flyby orbit design and orbit maintenance module. If the flyby orbit design and orbit maintenance module is selected, obtain the user input, calculate the design time and solve the orbit, calculate the orbit maintenance burn, and finally display the result; otherwise, select the flyby orbit design module, obtain the user input, select the orbital plane and orbit prediction, perform the particle swarm optimization algorithm, and finally display the result.

[0157] In one embodiment, a visualization method for a constellation inspection orbit design and visualization system based on the interconnection of STK and MATLAB is provided. The method includes:

[0158] Step 1: In the satellite tracking performance evaluation, establish a scenario according to the analysis period and the ephemeris file of the constellation, trigger the data update and maintenance component, construct a classification criterion based on three orbital characteristic parameters: orbital inclination, semi-major axis of the orbit, and right ascension of the ascending node, and update the constellation classification data.

[0159] Step 2: Operate various view components in the main interface, and realize the 2D / 3D display of the scenario in combination with the scenario established in Step 1.

[0160] Step 3: Trigger the orbit deployment query module, combine the scenario established in Step 1 and the constellation classification result, and display the orbit information of the constellation on the text information bar by selecting through the menu bar.

[0161] Step 4: Trigger the fly-around orbit design and orbit maintenance module, combine the scenario established in Step 1 and the constellation classification result, input the longitude and latitude of the ground target, the payload parameters of the ground station, the target star, the fly-around radius, the time step, the start and end times of the simulation, the control period, and the threshold parameters into the system, and output the fly-around orbit design result and the maintenance fuel consumption through the fly-around orbit design algorithm and the orbit maintenance algorithm, and dynamically display the fly-around trajectory and the maintenance effect.

[0162] Step 5: Trigger the grazing orbit design module, combine the scenario established in Step 1 and the constellation classification result, obtain the target orbital plane, grazing orbit altitude, payload action range, payload action angle, and total simulation duration information through interface interaction, obtain the optimal grazing orbit through the grazing algorithm, output the grazing orbit design parameters, and display the grazing effect.

[0163] For the specific limitations of the visualization method of the constellation inspection orbit design and visualization system based on the interconnection of STK and MATLAB, reference can be made to the limitations of the visualization system of the constellation inspection orbit design and visualization system based on the interconnection of STK and MATLAB in the above text, which will not be elaborated here.

[0164] In one embodiment, a computer device is provided, including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the computer program, it realizes the functions of each module of the visualization system of the constellation inspection orbit design and visualization system based on the interconnection of STK and MATLAB.

[0165] For the specific limitations of each module, reference can be made to the limitations of the visualization system of the constellation inspection orbit design and visualization system based on the interconnection of STK and MATLAB in the above text, which will not be elaborated here.

[0166] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the functions of the respective modules of the visualization system of the constellation inspection orbit design and visualization system based on the interconnection of STK and MATLAB are implemented.

[0167] For the specific limitations of each module, reference may be made to the limitations of the visualization system of the constellation inspection orbit design and visualization system based on the interconnection of STK and MATLAB in the foregoing text, which will not be elaborated herein.

[0168] The above description of the embodiments is for the convenience of those of ordinary skill in the art to understand and use the invention patent. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative efforts. Therefore, the invention patent is not limited to the above embodiments, and the improvements and modifications made by those skilled in the art without departing from the scope of the invention patent according to the disclosure of the invention patent should be within the protection scope of the invention patent.

Claims

1. A constellation inspection track design and visualization system based on STK and MATLAB interconnection, characterized in that: The system integrates STKX components in the form of ActiveX controls in the GUI interface through Matlab, and uses STK to implement the analysis and display of constellation orbit deployment query, flyby orbit design and orbit maintenance, and flyby orbit design modules; The system includes a main interface, an orbit deployment query module, a flyby orbit design and orbit maintenance module, and a flyby orbit design module; The orbit design and orbit maintenance module outputs the orbit design result through the orbit design algorithm; The orbit design algorithm is based on the CW equation and designs the orbit according to the load function requirements, specifically including: Step 3.1, set the input parameters, including the target star, simulation time, orbiting radius, threshold and control period; query the STK engine according to the input target star name, obtain the target star handle, calculate the absolute orbit information of the orbiting star based on the read target orbit six numbers, initiate a satellite creation request to the STK engine, and establish the orbiting star object; Step 3.2, in the natural drift phase, when the primary star orbit is a near-circular orbit, the polar coordinate form of the amplitude-phase of the CW equation is obtained through theoretical derivation: Where x(t), y(t), z(t), are the relative position vector and relative velocity vector of the orbiting star at time t, n is the average angular velocity of the target star, r x and r z are the amplitudes of radial and normal motion, respectively, l x and l y are the deviation values ​​of radial and track motion centers, α x and α z are the radial and normal initial phases, respectively; in, x0, y0, z0, are the relative position vector and relative velocity vector of the orbiting star at the initial moment respectively; Considering the symmetry of the configuration and the orbital radius r, the orbital design constraints are obtained: Step 3.3, query the STK engine according to the input target star name, read the six elements of the target star and calculate the average orbital angular velocity, and then calculate the relative orbital position velocity vector parameters of the orbiting star according to the method of step 3.2; Step 3.4, convert the orbiting star from the relative coordinate system to the absolute coordinate system; The orbit design and orbit maintenance module maintains fuel consumption through an orbit maintenance algorithm; the orbit maintenance algorithm specifically includes: Step 4.1, according to the input control cycle, threshold and simulation time, calculate the number of maintenance times in the analysis period, call the orbit prediction module of STK engine, obtain the orbit data of the target star and the orbiting star in the analysis period, and convert the absolute orbital elements of the orbiting star into ROE parameters according to the coordinate conversion relationship; Step 4.2, the control strategy is: the natural drift phase and the controlled flight phase are carried out alternately. After flying around the flying star for a natural flight cycle, the deviation from the reference orbit is calculated, and the orbit is corrected within the control cycle. According to the pulse analytical solution, the size and action time of the tangential pulse and the normal pulse are calculated; Step 4.3, storing the orbital data of the flying star under the two conditions of natural drift and orbit maintenance, repeating the above steps 4.1 to 4.2 until the time exceeds the analysis period; Step 4.4, draw the orbit of the flying star and show the number of orbit elements and pulse size of the flying star; Step 4.2 specifically includes: decoupling the orbit maintenance problem into out-of-orbit vector correction and in-orbit orbit correction based on relative dynamic characteristics; The effect of the pulse on the relative orbital elements is shown in the following formula: Where a is the semi-major axis of the reference orbit, Δδα k represents the configuration parameter, u k represents the average latitude argument of the reference orbit when the pulse is implemented, δv R ,δv T and δv N represent radial pulse, track pulse and normal pulse respectively; (1) The orbit correction in the orbital plane is performed by three tangential pulses, and its control solution is: Where T is the orbital period of the flying star, δa, δe and δλ are the relative orbital semi-major axis, relative orbital eccentricity and relative longitude argument, respectively. man ,δe man and δλ man is the configuration bias target parameter, δv t1 ,δv t2 and δv t3 are three tangential pulse sizes respectively; The latitude angle u corresponding to the three tangential pulse maneuvers M1 、u M2 and u M3 as follows: In the formula, They are δe man The component, δe x ,δe y are the components of δe respectively; (2) The out-of-plane vector correction uses a single normal pulse δv n After correction, the control solution is: In the formula, Δδi x is the component of the relative orbital inclination Δδi; The latitude argument u corresponding to the normal pulse n as follows: In the formula, Δδi x , Δδi y is the component of the relative orbital inclination Δδi.

2. According to claim 1, the constellation inspection track design and visualization system based on STK and MATLAB interconnection is characterized in that: The main interface is used to display the 2D / 3D scene display of the constellation satellite classification based on the STKX component, and to provide the entry port of each module; The orbital deployment query module is used to display the deployment status of each orbital plane of the constellation; The orbit design and orbit maintenance module is used to implement the orbit design and orbit maintenance fuel consumption calculation for the required constellation satellite inspection, and evaluate the orbit maintenance effect; The flyby orbit design module is used to implement the flyby orbit design for the required constellation satellite inspection on any orbital plane and demonstrate the flyby monitoring effect.

3. The constellation inspection track design and visualization system based on STK and MATLAB interconnection according to claim 1 is characterized in that: The configuration bias target parameter δa man ,δe man They are: δa man =-7γsin(2i)Δδi x In the formula, Δδi x is the component of the relative orbital inclination Δδi, i is the orbital inclination, γ is a constant coefficient, and is the nominal relative eccentricity δe nom The weight, To maintain the maximum allowable divergence of the relative eccentricity vector angle, δe max is the maximum allowed divergence of the relative eccentricity, is the phase angle of the E vector The differential of the latitude argument u of the formation main star.

4. The constellation inspection track design and visualization system based on STK and MATLAB interconnection according to claim 1 is characterized in that: The flyby trajectory design module obtains the optimal flyby trajectory through a flyby algorithm and outputs flyby trajectory design parameters; the flyby algorithm includes: Step 7.1, set the input parameters, including the target satellite, payload range, payload angle, total simulation time and orbit recursion interval information; Step 7.2, obtain the target satellite handle from the STK engine according to the input target satellite, initiate a data request for the target satellite inertial coordinate position and six orbital elements to the STK engine, and obtain the inertial coordinate position and six orbital elements of the target satellite at the total simulation time and discrete time input by the user; Step 7.3, based on the six numbers of the flyby orbit designed by absolute state recursion, directly initiate a satellite creation request to the STK engine to create a flyby satellite object; Step 7.4: The direction of the flyby satellite payload is opposite to the direction of the satellite pointing to the center of the earth, and the attitude is kept stable in three axes; the orbit prediction parameters of the target satellite group are output through STKengine and passed to the GUI backend program; for the longest flyby mission, a discrete recursive model is used to predict the orbit of the flyby satellite to determine the flyby point, flyby time and flyby angle; Step 7.5, based on the STK orbit prediction value of the target satellite and the flyby orbit prediction value obtained in step 7.4, construct a distance constraint function and an angle constraint function as the objective function of the particle swarm optimization algorithm; Step 7.6, based on the objective function, taking the six numbers of flyby star orbits as optimization variables, the particle swarm algorithm is used to optimize the flyby orbit with the longest inspection time for the orbital plane, that is, the optimal flyby orbit, and the flyby time for each target star is calculated and output.

5. The constellation inspection track design and visualization system based on STK and MATLAB interconnection according to claim 4 is characterized in that: The discrete recursive model described in step 7.4 is specifically: Assume the sampling frequency is T', when time t satisfies kT'≤t≤(k+1)T', k is any positive constant, and the state variable is The discrete state equation of the object sampled by zero-order holder, that is, the discrete recursive model, is: Convert the discrete recursive model into a simple form: Where A represents the state transfer matrix, B represents the control matrix, u represents the control acceleration, δx, δy, δz are the components of the relative position vector δr, is the relative velocity vector δv component, X[(k+1)T'], X(kT'), X(k+1), and X(k) are the state variables corresponding to the time instants (k+1)T', kT', k+1, and k, respectively; For a linear steady-state continuous-time system, the expression of the discrete equation obtained by solving it is shown as follows: In the formula, Among them, S nT' represents sin(nT'), C nT' It represents cos(nT'), where n is the average angular velocity of the target star.

6. The constellation inspection track design and visualization system based on STK and MATLAB interconnection according to claim 4, characterized in that: The objective function in step 7.5 is: Among them, r skim 、r target are the STK orbit prediction value of the target satellite and the flyby orbit prediction value obtained in step 7.4, respectively. D and E are the distance constraint and angle constraint, respectively.

7. The visualization method of the constellation inspection track design and visualization system based on the interconnection of STK and MATLAB according to any one of claims 1 to 6, characterized in that: The method comprises: Step 1: In the satellite tracking performance evaluation, a scenario is established according to the analysis period and the ephemeris file of the constellation, the data update maintenance component is triggered, and the classification criteria are constructed based on the three orbital characteristic parameters of orbital inclination, orbital semi-major axis and ascending node right ascension, and the constellation classification data is updated; Step 2, operate various view components in the main interface, and realize 2D / 3D display of the scene in combination with the scene established in step 1; Step 3, triggering the orbital deployment query module, combining the scenario established in step 1 and the constellation classification result, and displaying the orbital information of the constellation on the text information bar by selecting from the menu bar; Step 4, trigger the orbit design and orbit maintenance module, combine the scenario established in step 1 and the constellation classification results, input the longitude and latitude of the ground target, ground station load parameters, target star, orbit radius, time step, simulation start and end time, control cycle and threshold parameters to the system, output the orbit design result and maintenance fuel consumption through the orbit design algorithm and orbit maintenance algorithm, and dynamically display the orbit and maintenance effect; Step 5, trigger the flyby orbit design module, combine the scenario established in step 1 and the constellation classification results, obtain the target orbital plane, flyby orbit altitude, payload action range, payload action angle, and total simulation time information through interface interaction, obtain the optimal flyby orbit through the flyby algorithm, output the flyby orbit design parameters and display the flyby effect.

8. A computer device comprising a memory, a processor and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the functions of each module of the visualization system according to any one of claims 1 to 6 are realized.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the functions of each module of the visualization system according to any one of claims 1 to 6 are realized.

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