Three-dimensional surveying and mapping satellite task planning method and system

Abstract

The invention provides a three-dimensional surveying and mapping on-satellite task planning method and system, and the method comprises the steps: building a geometric relation of center ground points of a satellite mutual surveying and mapping region set during three-dimensional surveying and mapping, building an observability function based on a perturbation model, and carrying out the screening and selection of initial values according to the difference between a forward orbit and a reverse orbit, an initial value meeting the condition is substituted into an observability function for solving, the position and the speed of a target under an inertial system and the position and the speed of a satellite under the inertial system can be obtained after the time that the satellite pushes and scans to a geometric center ground point of a surveying and mapping area is obtained, and the expected attitude Euler of the satellite during push-scanning is calculated; and starting time and ending time of two times of push-broom can be obtained according to single-time push-broom time. And finally, giving a three-dimensional surveying and mapping control algorithm, calculating an expected attitude, a current attitude, an expected attitude angular velocity and a current attitude angular velocity of the satellite when a three-dimensional surveying and mapping task is executed, and completing three-dimensional surveying and mapping on-satellite task planning.

Description

Technical Field

[0001] The present invention relates to the technical field of satellite mission planning, and in particular to a mission planning method and system on a stereo mapping satellite. Background Art

[0002] With the continuous progress of my country's aerospace technology, the mission planning method of satellites has gradually changed to direct mission planning by on-orbit imaging satellites. One planning method for implementing on-orbit missions is to derive the conditional equation for the observability of the target by analyzing the geometric relationship between the satellite, the ground and the target, and solve the equation to determine the feasible time window for observing the target. The model of this method is relatively complex, and a reasonable model solving method needs to be constructed. How to use limited computing resources to obtain high-precision three-dimensional measurement data is the key to the specific implementation of this type of method. Among the existing surveying and mapping technologies, stereo mapping is an emerging technology that uses stereo images for surveying and three-dimensional modeling. In recent years, many stereo mapping satellites have been in orbit. Such satellites can obtain high-resolution stereo images of ground targets. The high-resolution cameras they carry can realize high-precision photogrammetry without ground control points, and are equipped with multiple medium-precision star sensors, which can meet the high-reliability, long-term, three-axis high-precision pointing determination requirements of surveying and mapping tasks.

[0003] According to the survey of existing patent results, there is a mission planning method for agile earth-bound satellites, but there is currently no on-board mission planning method based on stereo mapping. Summary of the invention

[0004] The present invention provides a stereo mapping satellite mission planning method and system, which are used to solve the defects in the prior art.

[0005] In a first aspect, the present invention provides a method for planning a task on a stereo mapping satellite, comprising: According to the spatial geometric relationship between the satellite, ground target points and the earth, the satellite observation condition equation is established; Screening the initial value of the satellite observation condition equation to obtain a screened initial value; Based on the filtered initial values, the time taken for the satellite to push-scan twice to the ground point at the geometric center of the surveying area and the corresponding expected attitude Euler angles are calculated; The total time of one push-scan of the satellite and the start and end time of two push-scans of the satellite are calculated from the time it takes the satellite to reach the ground point at the geometric center of the surveying area twice and the corresponding expected attitude Euler angle; Using multiple push-scan times of the satellite, the expected attitude, current attitude, expected attitude angular velocity and current attitude angular velocity of the satellite during the active push-scan process are calculated.

[0006] According to a stereo mapping satellite mission planning method provided by the present invention, a satellite observation condition equation is established according to the spatial geometric relationship between the satellite, the ground target point and the earth, including: Establish the geometric relationship between the satellite and the ground point at the geometric center of the survey area; The satellite observation condition equation is established based on the geometric relationship , in order to solve the time it takes for the satellite to push-scan to the ground point at the geometric center of the survey area.

[0007] According to a stereo mapping on-board mission planning method provided by the present invention, the initial value of the satellite observation condition equation is screened to obtain the screened initial value, including: The critical condition of the visible window is estimated by the longitude and latitude of the satellite's subsatellite point to obtain the quasi-visible segment; The initial values ​​after screening are obtained by screening different initial values ​​according to the prograde and retrograde orbits.

[0008] According to a method for planning a task on a stereo mapping satellite provided by the present invention, the initial values ​​are screened according to different prograde and retrograde orbits to obtain the screened initial values, including: by for The latitude of the satellite when it enters and exits the quasi-visible segment in the first orbital cycle from the starting point of the orbital cycle is calculated to obtain the true anomaly estimate when entering and exiting the quasi-visible segment. The argument of perigee is used to replace the argument of perigee at any time in the cycle. The true anomaly is used and the angle of approach The relationship between the angle of approach and and time The relationship between the two is used to find the time of entering and exiting the quasi-visible segment; According to the satellite's geocentric longitude during the orbit ascending and descending phases, combined with , , , and the time of entering and exiting the quasi-visible segment, and They represent the upper and lower limits of the satellite’s geocentric longitude during the orbit raising phase. and The upper and lower limits of the satellite's geocentric longitude during the descending phase are obtained to obtain the sub-satellite longitude when entering and leaving the quasi-visible phase. , , and , and They represent the upper and lower limits of the longitude of the lower point of the satellite when entering the quasi-visible period. and They respectively represent the upper and lower limits of the longitude of the lower point of the satellite when exiting the quasi-visible period.

[0009] According to a stereo mapping satellite mission planning method provided by the present invention, the satellite push-scan time to the geometric center ground point of the mapping area twice and the corresponding expected attitude Euler angle are calculated based on the filtered initial value, including: Substitute the screened initial value into the satellite observation condition equation , solved by Newton's method The zero point of the first push sweep to the ground point of the geometric center of the survey area is obtained. ; according to Calculate the expected attitude Euler angles for the first push sweep ; Substitute the screened initial value into the satellite observation condition equation , solved by Newton's method The zero point of the second push sweep is obtained to obtain the time when the second push sweep reaches the ground point of the geometric center of the survey area. ; according to Calculate the expected attitude Euler angles for the second push sweep .

[0010] According to a stereo mapping satellite mission planning method provided by the present invention, the total time of one push-scan of the satellite and the start time and end time of two push-scans of the satellite are calculated based on the time of two push-scans of the satellite to the ground point of the geometric center of the mapping area and the corresponding expected attitude Euler angles, including: Calculate the total time of a push sweep ; Calculate the start time of the first push sweep And the first sweep end time ; Calculate the start time of the second push sweep The second sweep end time .

[0011] According to a stereo mapping satellite mission planning method provided by the present invention, the expected attitude, current attitude, expected attitude angular velocity and current attitude angular velocity of the satellite during the active push-scan process are calculated using multiple push-scan times of the satellite, including: The current working camera is determined by the ground remote control command. When the high-resolution linear array is working, it is the coordinate system of the second camera of the high-resolution camera from this system. , when working with hyperspectral, it is the coordinate system of this system to the hyperspectral camera , when infrared is working, it is the coordinate system of this system to the infrared camera , get the satellite body coordinate system to the second camera coordinate system The attitude quaternion ; Determine the expected posture Euler angle under the 321 rotation sequence as , the corresponding expected attitude quaternion from the orbit system to the camera coordinate system without the drift angle correction is ; Using the deviation angle The desired attitude quaternion is To make corrections:

[0012] The expected attitude quaternion from the orbit system to the camera coordinate system after the drift angle correction is:

[0013] The desired attitude quaternion from the inertial system to the camera coordinate system is obtained as , the attitude quaternion from the satellite coordinate system to the camera coordinate system is , the expected attitude quaternion from the inertial system to the satellite system is ; Satellite current attitude quaternion Acquisition is determined by posture; Determine that the attitude angle rotation sequence including the drift angle correction is 3213, the c-axis is the orbital coordinate system, and the b-axis is the satellite body coordinate system; The yaw angle of the first rotation around the Zc axis , yaw angular velocity , the second rotation around the Yc axis, the pitch angle , pitch angular velocity , the third rotation around the Xc axis, the roll angle Push sweep, rotate around the Zb axis for the fourth time to correct the drift angle , then the projection of the satellite's angular velocity relative to the orbital system in the camera coordinate system is:

[0014] The projection of the satellite's angular velocity relative to the orbital system in the body coordinate system is: ; The angular velocity of the orbital system is Projected to the satellite coordinate system:

[0015] The expected total angular velocity of the satellite is obtained as:

[0016] Satellite angular velocity Obtained by posture determination.

[0017] In a second aspect, the present invention further provides a stereo mapping satellite mission planning system, comprising: The first calculation module is used to establish a satellite observation condition equation according to the spatial geometric relationship between the satellite, the ground target point and the earth; A second calculation module is used to screen the initial value of the satellite observation condition equation to obtain a screened initial value; A third calculation module is used to calculate the time for the satellite to push-scan twice to the geometric center ground point of the surveying and mapping area and the corresponding expected attitude Euler angle based on the filtered initial value; The fourth calculation module is used to calculate the total time of one push sweep of the satellite and the start and end time of two push sweeps of the satellite based on the time of two push sweeps of the satellite to the ground point of the geometric center of the surveying area and the corresponding expected attitude Euler angle; The fifth calculation module is used to calculate the expected attitude, current attitude, expected attitude angular velocity and current attitude angular velocity of the satellite during the active push-scan process using multiple push-scan times of the satellite.

[0018] In a third aspect, the present invention further provides an electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, it implements any of the above-described methods for planning a stereoscopic mapping satellite mission.

[0019] In a fourth aspect, the present invention further provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements any of the above-described methods for planning a task on a stereo mapping satellite.

[0020] The stereo mapping on-board mission planning method and system provided by the present invention establishes and solves the satellite observable condition equation based on stereo mapping technology, and accurately calculates the start time and end time of the satellite push-scan and the expected attitude of the satellite. Compared with the previous mission planning methods, the present invention has the advantage of using limited on-board resources to achieve convergence in a shorter time and fewer iterations, that is, to complete the given mission. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 It is a schematic diagram of the process of the on-board task planning method for stereo mapping provided by the present invention; Figure 2 It is a schematic diagram of the geometric relationship between the satellite provided by the present invention and the ground point of the geometric center of the surveying and mapping area; Figure 3 It is a schematic diagram of the total pointing deviation during a push-scan period of an on-orbit satellite test strip provided by the present invention; Figure 4 It is a schematic diagram of the pitch angle deviation of the satellite orbit system during a push-scan period of an on-orbit satellite test strip provided by the present invention; Figure 5 It is a schematic diagram of the roll angle deviation of the satellite orbit system during a push-scan period of an on-orbit satellite test strip provided by the present invention; Figure 6 It is a schematic diagram of the yaw angle deviation of the satellite orbit system during a push-scan period of an on-orbit satellite test strip provided by the present invention; Figure 7 It is a schematic diagram of the total pointing deviation during the second push-scan of the on-orbit satellite test strip provided by the present invention; Figure 8 It is a schematic diagram of the pitch angle deviation of the satellite orbit system during the second push-scan of the on-orbit satellite test strip provided by the present invention; Fig. 9 It is a schematic diagram of the roll angle deviation of the satellite orbit system during the second push-scan of the on-orbit satellite test strip provided by the present invention; Fig.10 It is a schematic diagram of the yaw angle deviation of the satellite orbit system during the second push-scan of the on-orbit satellite test strip provided by the present invention; Fig.11 It is a structural schematic diagram of the on-board mission planning system for stereo mapping provided by the present invention; Fig.12 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] In view of the problems existing in the prior art, the present invention proposes a method for onboard mission planning for stereo mapping. It should be noted that the onboard mission planning problem usually refers to specifying which time period the satellite observes which ground target and the attitude during the observation under the condition of satisfying various constraints, while making the objective function containing information such as the number of images and the observation area reach the optimal value.

[0025] Figure 1 FIG. 1 is a flow chart of a method for planning a task on a stereo mapping satellite provided by an embodiment of the present invention. Figure 1 As shown, including: Step 100: Establishing satellite observation condition equations according to the spatial geometric relationship between the satellite, the ground target point and the earth; Step 200: screening the initial value of the satellite observation condition equation to obtain a screened initial value; Step 300: Calculate the time for the satellite to push-scan twice to the geometric center ground point of the surveying area and the corresponding expected attitude Euler angle based on the filtered initial value; Step 400: Calculate the total time of one push-sweep of the satellite and the start and end times of two push-sweeps of the satellite based on the time taken for the satellite to push-sweep twice to the ground point at the geometric center of the surveying area and the corresponding expected attitude Euler angles; Step 500: Utilizing multiple push-scan times of the satellite, calculate the expected attitude, current attitude, expected attitude angular velocity, and current attitude angular velocity of the satellite during the active push-scan process.

[0026] The embodiment of the present invention first constructs the geometric relationship between the central ground points of the satellite mutual mapping area set during stereo mapping, and then based on Perturbation Model Establishes Observability Function Then, the initial values ​​are screened and selected according to the different forward and retrograde orbits. This step is mainly to screen out the Initial values ​​with observable possibilities are involved in the solution and some incomprehension can be avoided. By bringing the initial values ​​that meet the conditions into the observability function for solution, the position and velocity of the target in the inertial system and the position and velocity of the satellite in the inertial system can be obtained after the time when the satellite pushes to the ground point at the geometric center of the surveying area is obtained, and the expected Euler attitude of the satellite during the push-sweep can be calculated. Finally, the start time and end time of two push-sweeps can be obtained according to the single push-sweep time. The present invention uses Newton's method to find the observability function The zero point is obtained, thereby determining the visible start and end time of the target. When the initial value is designed reasonably, the convergence speed of this method is extremely fast.

[0027] The specific steps include: Step 1: Establish satellite observation condition equation, which specifically includes the following steps: Step 1.1, establish the geometric relationship between the satellite and the ground point of the geometric center of the surveying area; like Figure 2 As shown, the satellite is pushed to the ground point at the geometric center of the survey area. T When the ground point T The geocentric vector is denoted as ,satellite S The geocentric vector is denoted as , the speed is recorded as , then the radius vector of the ground point relative to the satellite is (1) To make the center of the camera lens point to the ground point, there should be (2) is the satellite orbital angular momentum The unit vector is calculated as follows: (3) Yaw angle , then the satellite attitude corresponds to The axis points to (4) Since the stereo mapping angle is , the expected attitude pitch angle at the first push sweep is ,but Axis and satellite's geocentric radius Angle of Radius Vector , and the satellite-target line does not pass through the earth, we have: (5) The expected attitude pitch angle during the second push sweep is ,but Axis and satellite's geocentric radius Angle of Radius Vector .

[0028] Step 1.2, construct the observability function F(t) based on the relevant geometric relationship; When the satellite reaches the ground point at the geometric center of the survey area hour, and The angle between , and the star-to-earth direction vector The angle between , from the geometric relationship, we know (6) The above formula The derivation is:

[0029] At the angle In the range of variation, is an increasing function.

[0030] From the dihedral angle formula, we can get: ,have

[0031] again ,have

[0032] Maximum rolling angle during stereo mapping .

[0033] When the earth is regarded as a standard sphere, and hour, Take the maximum value ,

[0034] Ignoring the constraint that the satellite-target line does not pass through the earth, the observation function constructed based on equation (5) is: (7) Using the vector triple product to expand the Lagrange formula, we have (8) right To perform the derivation: (9) For equation (7), the visibility function and its derivatives can be calculated.

[0035] when (10) When , the target is at the critical position of the satellite's visible range.

[0036] Step 2, initial value selection and screening, can be divided into the following two steps; Step 2.1, only considering the latitude and longitude of the satellite sub-satellite point to estimate the critical conditions of the visible window, so as to obtain the "quasi-visible segment"; Using formula (11), the true anomaly angle Convert to eccentric anastomosis , pay attention to retaining the quadrant information and period information of the true anomaly.

[0037] (11) Using the eccentric approach angle shown in formula (12) and time The relationship between them can be used to determine the time of entering and exiting the quasi-visible segment.

[0038] (12) For the initial moment, (13) Step 2.2, screen the initial values ​​according to the different prograde and retrograde orbits, select the initial values ​​that have the possibility of observing the target T, and participate in the solution; Initial Value The screening is as follows, based on the first orbital period (in for The latitude of the satellite when it enters and exits the quasi-visible segment within the orbital period (the starting point of the orbital period) is calculated to obtain the true anomaly estimate when entering and exiting the quasi-visible segment. The argument of perigee is used to replace the argument of perigee at any time in the period, and the true anomaly is used to calculate the true anomaly estimate when entering and exiting the quasi-visible segment. and the angle of approach The relationship between the angle of approach and and time The relationship between them can be used to determine the time of entering and exiting the quasi-visible segment.

[0039] According to the satellite's geocentric longitude during the ascending and descending orbits (different for prograde and retrograde orbits), combined with , , , and the time of entering and exiting the quasi-visible segment, and They represent the upper and lower limits of the satellite’s geocentric longitude during the orbit raising phase. and The upper and lower limits of the satellite's geocentric longitude during the descending phase are obtained to obtain the sub-satellite point longitude when entering and leaving the quasi-visible phase, that is, , , and . Note that after solving The value range is limited to , and They represent the upper and lower limits of the longitude of the lower point of the satellite when entering the quasi-visible period. and They respectively represent the upper and lower limits of the longitude of the lower point of the satellite when exiting the quasi-visible period.

[0040] Considering the longitude From the jump to The possibility of , if (direct and retrograde orbits are different) (14) Then the corresponding and As a set of feasible initial values, substitute them into equation (10) and solve them.

[0041] Similarly, if (the direct and retrograde orbits are different) (15) Then the corresponding and As a set of feasible initial values, substitute them into equation (10) and solve them.

[0042] Otherwise, The orbital period does not have The possibility of making observations does not participate in the solution.

[0043] This screening can also avoid The incomprehension of.

[0044] Step 3: Calculate the expected Euler angles for the first push sweep and the time of the first push sweep to the ground point at the geometric center of the survey area and the expected attitude Euler angles during the second push sweep and the time of the second push sweep to the ground point at the geometric center of the survey area ; Based on the above calculation formula, we first calculate the time of the satellite's two push-scanning mapping area's geometric center ground point, and then calculate the expected attitude Euler during the push-scanning according to the formula, as follows: Step 3.1, bring the initial value selected in step 2.2 into the observability function in step 1.2 to calculate the time of the first push sweep to the ground point at the geometric center of the survey area , the calculation method can be used to solve the zero point of the observation equation by Newton's method. The solution of the equation is the time for the push scan to reach the ground point at the geometric center of the survey area; Step 3.2: The time from the first push sweep to the ground point at the geometric center of the survey area calculated in step 3.1 According to the calculation of the expected attitude Euler angle at the first push sweep , the expected posture is calculated as follows: Obtain the time it takes for the satellite to push-scan to the ground point at the geometric center of the survey area , Then, the position of the target in the inertial system can be obtained. ,speed , and the position of the satellite in the inertial frame ,speed .

[0045] Yaw angle , then the satellite's expected attitude corresponds to The axis points to

[0046] Then the satellite's expected attitude coordinate system is

[0047] The satellite's current orbital coordinate system is

[0048] The transformation matrix from the inertial system to the satellite's desired attitude coordinate system is:

[0049] The transformation matrix from the inertial system to the satellite's current orbital coordinate system is:

[0050] The transformation matrix from the satellite's current orbital coordinate system to the satellite's expected attitude coordinate system is:

[0051] Define the Euler angles of the 321 transition (yaw, pitch, roll), the attitude matrix is

[0052] When the satellite pushes to the ground point at the geometric center of the survey area, the required rolling angle is

[0053] Then, the expected attitude Euler angle of the satellite during the first push sweep is (321 forwarding sequence), the expected attitude Euler angle during the second push sweep (321 transferred). Due to the maximum rolling angle during stereo mapping, . The solutions that do not meet this condition need to be discarded.

[0054] Step 3.3, bring the initial value selected in step 2.2 into the observation function in step 1.2 to calculate the time for the second push sweep to the ground point at the geometric center of the survey area ; Step 3.4: The time from the second push sweep to the ground point at the geometric center of the survey area calculated in step 3.3 According to the calculation of the expected attitude Euler angle during the second push sweep , the expected posture calculation method is the same as step 3.2; Step 4: Calculate the total time of a push sweep And the start and end times of the two push sweeps.

[0055] Step 4.1: , calculate the total time of a single push sweep.

[0056] Then, the start and end time of the two push sweeps can be calculated. The specific steps are as follows: Finding functions using Newton's method The zero point of the target is determined to determine the start and end time of the target. Newton's solution has Convergence speed: When the initial value is designed reasonably, it has a faster convergence speed, and the implementation method is as follows.

[0057] Assume that the initial value of the solution is , in each iteration, (16) when and The difference is less than a small amount When , the solution process converges to is the numerical solution of the equation and the iteration ends.

[0058] Step 4.2, calculate the start time of the first push sweep And the first sweep end time ; Step 4.3, calculate the start time of the second push sweep The second sweep end time .

[0059] Note that if the number of iterations is greater than a certain upper limit If it still does not converge when , then the initial value is considered unreliable. It cannot be designed to be too large, otherwise there is a possibility of converging to the zero point in other visible segments. Considering the fast convergence characteristics of the Newton iteration method, this report takes .

[0060] Step 5, calculate the expected attitude, current attitude, expected attitude angular velocity, and current attitude angular velocity during the push sweep process; the specific steps are as follows: Step 5.1: Desired posture The current working camera is determined by the ground remote control command. When the high-resolution linear array is working, it is the coordinate system of the second camera of the high-resolution camera from this system. , when working with hyperspectral, it is the coordinate system of this system to the hyperspectral camera , when infrared is working, it is the coordinate system of this system to the infrared camera (Without adding the drift angle). The attitude quaternion from the satellite system to the corresponding camera coordinate system can be obtained .

[0061] According to the on-board planning program or ground remote control instructions, the expected Euler angle under the 321 transformation sequence can be obtained as , the corresponding expected attitude quaternion from the orbit system to the camera coordinate system without the drift angle correction is This posture needs to be corrected for the drift angle. According to the drift angle calculation dynamic link library, it is obtained .

[0062]

[0063] The expected attitude quaternion from the orbit system to the camera coordinate system after the drift angle correction is:

[0064] Then the desired attitude quaternion from the inertial system to the camera coordinate system is Since the attitude quaternion from the satellite system to the corresponding camera coordinate system is , then the expected attitude quaternion from the inertial system to the satellite system is .

[0065] Step 5.2, current posture determination Satellite current attitude quaternion Obtained by posture determination.

[0066] Step 5.3, calculate the desired attitude angular velocity Next, the satellite The expected angular velocity at time is solved.

[0067] First, solve the relative angular velocity relative to the orbital system. Since the attitude rotation order including the drift angle correction is 3213, the angular velocities of the first three rotations are all 0, and the fourth rotation around the Zb axis is used for drift angle correction. The yaw angular velocity It can be obtained from the drift angle calculation dynamic link library. Then the satellite's relative orbital angular velocity is projected in the camera coordinate system as

[0068] The projection of the satellite's angular velocity relative to the orbital system in the body coordinate system is: .

[0069] On the other hand, the angular velocity of the orbital system is , projecting it to the satellite coordinate system

[0070] The expected total angular velocity of the satellite is

[0071] Step 5.4, calculate the current attitude angular velocity Satellite angular velocity Obtained by posture determination.

[0072] Based on the above embodiments, in order to verify the effectiveness of the present invention in the on-board task planning of stereo mapping satellites, the satellite is tested on-orbit, and the stereo mapping task mode of the high-resolution camera calibrated for the sky is analyzed.

[0073] The test parameters of this task mode are as follows: 1. Target parameters Goal 1: Sao_Paulo Longitude -46.6° Latitude -23.56° Height: 767.921m Stereo mapping angle: 45° 2. Command parameters Stereo mapping task of high-resolution camera calibrated for the sky (ground planning): Surveying angle 45° Strip 1 parameters: Imaging started at 487517039s Yaw angle 0° Pitch angle 22.5° Roll angle -6.737703145388° Push sweep duration 30.750433s Strip 2 parameters: Imaging starts at 487517102s. Yaw angle 0° Pitch angle -22.5° Roll angle -4.144166010715° Push sweep duration 30.750433s Based on the above parameters, the satellite was tested on orbit and the on-board task planning method for stereo mapping was simulated. The test results are as follows: The expected Euler angles for strip 1 are (0, 22.5, -6.7377)°, the total pointing deviation during ground sweep is 0.01120° (3σ), the X-axis attitude stability is 0.00067° / s (3σ), the Y-axis attitude stability is 0.00091° / s (3σ), and the Z-axis attitude stability is 0.00071° / s (3σ). Figure 3-Figure 6 shown.

[0074] The expected Euler angles for strip 2 are (0, -22.5, -4.1441)°, and the attitude converges after 28s of maneuvering. The total pointing deviation during the ground push scan is 0.01513° (3σ), the X-axis attitude stability is 0.00062° / s (3σ), the Y-axis attitude stability is 0.00105° / s (3σ), and the Z-axis attitude stability is 0.00087° / s (3σ). Figure 7-10 shown.

[0075] Above Figure 3-Figure 10 The simulation results verify that the proposed method for on-board stereo mapping mission planning can quickly achieve the convergence of satellite attitude error to a relatively low level when the high-resolution camera completes the stereo mapping mission, thus meeting the imaging accuracy requirements and ensuring the smooth completion of the satellite's on-orbit mission.

[0076] The stereo mapping satellite mission planning system provided by the present invention is described below. The stereo mapping satellite mission planning system described below and the stereo mapping satellite mission planning method described above can be referenced to each other.

[0077] Fig.11Schematic diagram of the structure of the on-board mission planning system for stereo mapping provided by an embodiment of the present invention. Fig.11 As shown, it includes: a first calculation module 1101, a second calculation module 1102, a third calculation module 1103, a fourth calculation module 1104 and a fifth calculation module 1105, wherein: The first calculation module 1101 is used to establish a satellite observation condition equation according to the spatial geometric relationship between the satellite, the ground target point and the earth; the second calculation module 1102 is used to filter the initial value of the satellite observation condition equation to obtain the filtered initial value; the third calculation module 1103 is used to calculate the time when the satellite pushes and sweeps twice to the ground point at the geometric center of the surveying and mapping area, and the corresponding expected attitude Euler angle based on the filtered initial value; the fourth calculation module 1104 is used to calculate the total push-sweep time of the satellite and the start time and end time of the satellite's two push-sweeps based on the time when the satellite pushes and sweeps twice to the ground point at the geometric center of the surveying and mapping area and the corresponding expected attitude Euler angle; the fifth calculation module 1105 is used to use multiple push-sweep times of the satellite to calculate the expected attitude, current attitude, expected attitude angular velocity and current attitude angular velocity of the satellite during the active push-sweep process.

[0078] Fig.12 An example of a physical structure diagram of an electronic device is shown in FIG. Fig.12 As shown, the electronic device may include: a processor (processor) 1210, a communication interface (Communications Interface) 1220, a memory (memory) 1230 and a communication bus 1240, wherein the processor 1210, the communication interface 1220, and the memory 1230 communicate with each other through the communication bus 1240. The processor 1210 can call the logic instructions in the memory 1230 to execute the stereo mapping on-board mission planning method, which includes: establishing a satellite observation condition equation based on the spatial geometric relationship between the satellite, the ground target point and the earth; filtering the initial value of the satellite observation condition equation to obtain the filtered initial value; calculating the time for the satellite to push-scan twice to the ground point at the geometric center of the mapping area and the corresponding expected attitude Euler angle based on the filtered initial value; calculating the total push-scan time of the satellite and the start time and end time of the satellite's two push-scans based on the time for the satellite to push-scan twice to the ground point at the geometric center of the mapping area and the corresponding expected attitude Euler angle; using the satellite's multiple push-scan times, calculate the expected attitude, current attitude, expected attitude angular velocity and current attitude angular velocity of the satellite during the active push-scan process.

[0079] In addition, the logic instructions in the above-mentioned memory 1230 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on such an understanding, the technical solution of the present invention can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium, including several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0080] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to execute the stereoscopic mapping on-board mission planning method provided by the above-mentioned methods, the method comprising: establishing a satellite observation condition equation based on the spatial geometric relationship between the satellite, the ground target point and the earth; screening the initial value of the satellite observation condition equation to obtain the screened initial value; calculating the time when the satellite pushes and sweeps twice to the ground point at the geometric center of the mapping area, and the corresponding expected attitude Euler angle based on the screened initial value; calculating the total push-scan time of the satellite and the start time and end time of the satellite's two push-scans based on the time when the satellite pushes and sweeps twice to the ground point at the geometric center of the mapping area and the corresponding expected attitude Euler angle; using the multiple push-scan times of the satellite, calculating the expected attitude, current attitude, expected attitude angular velocity and current attitude angular velocity of the satellite during the active push-scan process.

[0081] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0082] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0083] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for planning a stereo mapping mission on a satellite, characterized in that: include: According to the spatial geometric relationship between the satellite, ground target points and the earth, the satellite observation condition equation is established; Screening the initial value of the satellite observation condition equation to obtain a screened initial value; Based on the filtered initial values, the time taken for the satellite to push-scan twice to the ground point at the geometric center of the surveying area and the corresponding expected attitude Euler angles are calculated; The total time of one push-scan of the satellite and the start and end time of two push-scans of the satellite are calculated from the time it takes the satellite to reach the ground point at the geometric center of the surveying area twice and the corresponding expected attitude Euler angle; Using multiple push-scan times of the satellite, the expected attitude, current attitude, expected attitude angular velocity and current attitude angular velocity of the satellite during the active push-scan process are calculated.

2. The on-board task planning method for stereo mapping according to claim 1, characterized in that: According to the spatial geometric relationship between the satellite, ground target points and the earth, the satellite observation condition equation is established, including: Establish the geometric relationship between the satellite and the ground point at the geometric center of the survey area; The satellite observation condition equation is established based on the geometric relationship , in order to solve the time it takes for the satellite to push-scan to the ground point at the geometric center of the survey area.

3. The on-board task planning method for stereo mapping according to claim 1, characterized in that: The initial value of the satellite observation condition equation is screened to obtain the screened initial value, including: The critical condition of the visible window is estimated by the longitude and latitude of the satellite's subsatellite point to obtain the quasi-visible segment; The initial values ​​after screening are obtained by screening different initial values ​​according to the prograde and retrograde orbits.

4. The method for planning a task on a stereo mapping satellite according to claim 3, characterized in that: The initial values ​​after screening are obtained according to different prograde and retrograde orbits, including: by for The latitude of the satellite when it enters and exits the quasi-visible segment in the first orbital cycle from the starting point of the orbital cycle is calculated to obtain the true anomaly estimate when entering and exiting the quasi-visible segment. The argument of perigee is used to replace the argument of perigee at any time in the cycle. The true anomaly is used and the angle of approach The relationship between the angle of approach and and time The relationship between the two is used to find the time of entering and exiting the quasi-visible segment; According to the satellite's geocentric longitude during the orbit ascending and descending phases, combined with , , , and the time of entering and exiting the quasi-visible segment, and They represent the upper and lower limits of the satellite’s geocentric longitude during the orbit raising phase. and The upper and lower limits of the satellite's geocentric longitude during the descending phase are obtained to obtain the sub-satellite longitude when entering and leaving the quasi-visible phase. , , and , and They represent the upper and lower limits of the longitude of the lower point of the satellite when entering the quasi-visible period. and They respectively represent the upper and lower limits of the longitude of the lower point of the satellite when exiting the quasi-visible period.

5. The method for planning a stereoscopic mapping mission on a satellite according to claim 1, characterized in that: The time for the satellite to push-scan twice to the geometric center ground point of the surveying area and the corresponding expected attitude Euler angles are calculated based on the filtered initial values, including: Substitute the screened initial value into the satellite observation condition equation , solved by Newton's method The zero point of the first push sweep to the ground point of the geometric center of the survey area is obtained. ; according to Calculate the expected attitude Euler angles for the first push sweep ; Substitute the screened initial value into the satellite observation condition equation , solved by Newton's method The zero point of the second push sweep is obtained to obtain the time when the second push sweep reaches the ground point of the geometric center of the survey area. ; according to Calculate the expected attitude Euler angles for the second push sweep .

6. The method for planning a stereo mapping mission on a satellite according to claim 1, characterized in that: The total time of one satellite push-sweep and the start and end time of two satellite push-sweeps are calculated from the time when the satellite pushes twice to the ground point at the geometric center of the surveying area and the corresponding expected attitude Euler angle, including: Calculate the total time of a push sweep ; Calculate the start time of the first push sweep And the first sweep end time ; Calculate the start time of the second push sweep The second sweep end time .

7. The method for planning a stereoscopic mapping mission on a satellite according to claim 1, characterized in that: Using multiple push-scan times of the satellite, the expected attitude, current attitude, expected attitude angular velocity and current attitude angular velocity of the satellite during the active push-scan process are calculated, including: The current working camera is determined by the ground remote control command. When the high-resolution linear array is working, it is the coordinate system of the second camera of the high-resolution camera from this system. , when working with hyperspectral, it is the coordinate system of this system to the hyperspectral camera , when infrared is working, it is the coordinate system of this system to the infrared camera , get the satellite body coordinate system to the second camera coordinate system The attitude quaternion ; Determine the expected posture Euler angle under the 321 rotation sequence as , the corresponding expected attitude quaternion from the orbit system to the camera coordinate system without the drift angle correction is ; Using the deviation angle The desired attitude quaternion is To make corrections: The expected attitude quaternion from the orbit system to the camera coordinate system after the drift angle correction is: The desired attitude quaternion from the inertial system to the camera coordinate system is obtained as , the attitude quaternion from the satellite coordinate system to the camera coordinate system is , the expected attitude quaternion from the inertial system to the satellite system is ; Satellite current attitude quaternion Acquisition determined by posture; Determine that the attitude angle rotation sequence including the drift angle correction is 3213, the c-axis is the orbital coordinate system, and the b-axis is the satellite body coordinate system; The yaw angle of the first rotation around the Zc axis , yaw angular velocity , the second rotation around the Yc axis, the pitch angle , pitch angular velocity , the third rotation around the Xc axis, the roll angle Push sweep, rotate around the Zb axis for the fourth time to correct the drift angle , then the projection of the satellite's angular velocity relative to the orbital system in the camera coordinate system is: The projection of the satellite's angular velocity relative to the orbital system in the body coordinate system is: ; The angular velocity of the orbital system is Projected to the satellite coordinate system: The expected total angular velocity of the satellite is obtained as: Satellite angular velocity Obtained by posture determination.

8. A stereo mapping satellite mission planning system, characterized in that: include: The first calculation module is used to establish a satellite observation condition equation according to the spatial geometric relationship between the satellite, the ground target point and the earth; A second calculation module is used to screen the initial value of the satellite observation condition equation to obtain a screened initial value; A third calculation module is used to calculate the time for the satellite to push-scan twice to the geometric center ground point of the surveying and mapping area and the corresponding expected attitude Euler angle based on the filtered initial value; The fourth calculation module is used to calculate the total time of one push sweep of the satellite and the start time and end time of two push sweeps of the satellite based on the time of two push sweeps of the satellite to the ground point of the geometric center of the surveying area and the corresponding expected attitude Euler angle; The fifth calculation module is used to calculate the expected attitude, current attitude, expected attitude angular velocity and current attitude angular velocity of the satellite during the active push-scan process by using multiple push-scan times of the satellite.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein: When the processor executes the program, the stereo mapping satellite mission planning method as described in any one of claims 1 to 7 is implemented.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method for planning a task on a stereo mapping satellite as claimed in any one of claims 1 to 7 is implemented.

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