Ground descending speed push-broom satellite task planning method and system

Abstract

The invention provides an on-satellite task planning method and system for reduced ground velocity push-broom. The method comprises the following steps: firstly, solving an expected attitude Euler angle during one-time ground velocity push-broom through a Newton iteration method, and push-broom to a moment of a geometric center ground point of a surveying and mapping area; then giving a ground velocity reduction push-broom mode control algorithm, and solving an expected attitude, a current attitude, an expected attitude angular velocity and a current attitude angular velocity of the satellite during ground velocity reduction push-broom by the algorithm; and finally, the starting moment and the ending moment of ground speed reduction stable push-broom are solved by using a ground speed reduction push-broom mode control algorithm, and satellite push-broom task planning is completed. According to the invention, not only is a ground speed reduction on-satellite task planning method provided, but also a specific ground speed reduction push-broom mode control algorithm is provided, so that the satellite can complete the push-broom task in an expected attitude, and high-precision controllability is realized.

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 for a ground-speed push-sweep satellite. Background Art

[0002] Existing agile optical remote sensing satellites rely on their rapid attitude maneuvering capabilities when performing missions and are able to complete high-precision imaging of ground areas in a relatively short period of time.

[0003] However, traditional push-broom missions usually use a fixed ground-speed push-broom method, which limits the satellite's adaptability to special environments or needs. In particular, when long-term high-precision observations or coverage of special areas are required, the fixed push-broom speed cannot meet the needs. Therefore, in recent years, a variety of new push-broom modes and control methods have been proposed for remote sensing satellites to improve the flexibility and efficiency of the mission. Some solutions in the prior art have improved the completion of satellite imaging missions by increasing the satellite's attitude maneuverability and optimizing the push-broom path, but there are still some shortcomings, especially under complex observation conditions, traditional methods have certain limitations in accurately controlling attitude and speed. Summary of the invention

[0004] The present invention provides a method and system for planning a mission on a ground-speed push-sweep satellite, 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 mission on a ground-speed push-sweep satellite, comprising: According to the spatial geometric relationship between the satellite, the ground target point and the earth, the expected attitude Euler angle at 1 times the ground speed push-scan and the time when the push-scan reaches the ground point at the geometric center of the surveying area are calculated; The control algorithm of the push-scan mode at ground speed is adopted to calculate the expected attitude quaternion from the inertial system to the camera coordinate system without drift angle correction when the satellite is at ground speed, the expected attitude quaternion from the inertial system to the satellite's own system, and the expected total angular velocity of the attitude when the satellite is at ground speed. The current attitude quaternion and the current attitude angular velocity of the satellite are obtained from the satellite attitude determination. Calculate the start time of the satellite's ground-speed stabilization push-scanning and the corresponding expected attitude Euler angle, as well as the end time of the ground-speed stabilization push-scanning and the corresponding expected attitude Euler angle; Calculate the satellite's ground speed push-scan start time and expected attitude Euler angle.

[0006] According to a mission planning method on a ground-speed push-sweep satellite provided by the present invention, the expected attitude Euler angles at 1 times the ground speed push-sweep and the time when the push-sweep reaches the ground point at the geometric center of the surveying area are calculated according to the spatial geometric relationship between the satellite, the ground target point and the earth, including: Determine the expected attitude pitch angle at 1 times ground speed push sweep as When the satellite is in the center of the survey area, the geometric relationship between the satellite and the ground point is established; According to the geometric relationship between the satellite and the ground point at the geometric center of the surveying area, a satellite over-the-top time function is established; Newton's method is used to find the zero point of the time function of passing the top, and the time when the sweep is pushed to the ground point at the geometric center of the surveying area at 1 times the speed is calculated. ; The time from 1x push-scanning to the ground point at the geometric center of the survey area Calculate the expected attitude Euler angles for 1x ground speed push sweep .

[0007] According to a method for planning a mission on a ground-speed push-sweep satellite provided by the present invention, the expected attitude quaternion from an inertial system to a satellite system is calculated, including: According to the dynamic link library of the deviation angle calculation, it is obtained :

[0008] in, is a unit vector, indicating the direction of the rotation axis, is the rotation quaternion corrected by the drift angle; The expected attitude quaternion from the orbit system to the camera coordinate system after the drift angle correction is:

[0009] Determine the attitude quaternion of the satellite's own system to the corresponding camera coordinate system: , then the expected attitude quaternion from the inertial system to the satellite system is: .

[0010] According to a method for planning a mission on a ground-descent speed push-sweep satellite provided by the present invention, the expected total angular velocity of the attitude of the satellite during ground-descent speed push-sweep is calculated, comprising: Determine that the attitude angle rotation sequence including the drift angle correction is 3213, the c-axis is the camera coordinate system, and the b-axis is the satellite body coordinate system; The yaw angle of the first rotation around the Zc axis , , the second rotation around the Yc axis, the pitch angular velocity Push sweep, and They are the desired attitude pitch angle of the current and previous control cycles, the third rotation around the Xc axis, and the roll angle Push sweep, and are the expected attitude roll angles of the current and previous control cycles, the fourth rotation around the Zb axis for drift angle correction, and the yaw angular velocity It can be obtained from the drift angle calculation dynamic link library, and the satellite's relative orbital angular velocity is projected in the camera coordinate system as:

[0011] M1 represents the rotation matrix around the X axis, M2 represents the rotation matrix around the Y axis, and M3 represents the rotation matrix around the Z axis; The projection of the satellite's angular velocity relative to the orbital system in the body coordinate system is:

[0012] The angular velocity of the orbital system is Projected to the satellite coordinate system:

[0013] is the satellite's ground speed ratio; The expected total angular velocity of the satellite is obtained as: .

[0014] According to a method for planning a mission on a ground-speed push-sweep satellite provided by the present invention, the start time of the ground-speed stable push-sweep of the satellite and the corresponding expected attitude Euler angle are calculated, including: Determine the ground speed reduction ratio as The total time for stable push-broom at reduced ground speed is , combined with the 1x speed push sweep to the geometric center ground point of the survey area Get the start time of the ground speed reduction stable push sweep ; Get satellite position The ground sweep point when the sweep is performed at 1 times the ground speed , and the satellite's position The actual ground sweep point at the start of the stable sweep at the time of ground speed reduction , The corresponding time is ; Calculated using the ground speed reduction push-broom control algorithm and , calculate the corresponding expected posture Euler angle .

[0015] According to a method for planning a mission on a ground-speed push-sweep satellite provided by the present invention, the end time of the ground-speed stable push-sweep and the corresponding expected attitude Euler angle are calculated, including: Determine the end time of the stable push sweep at reduced ground speed , the corresponding satellite position for push-scanning at 1 times the ground speed is , the ground push sweep point is ; Get satellite position The actual ground sweep point at the end of the ground speed sweep , The corresponding time is ; Calculated using the ground speed reduction push-broom control algorithm and , calculate the corresponding expected posture Euler angle .

[0016] According to a ground-speed push-sweep mission planning method provided by the present invention, the ground-speed push-sweep start time and the expected attitude Euler angle of the satellite are calculated, including: Calculate the pitch rate during steady push sweep at reduced ground speed and rolling angular velocity , through the pitch angular velocity Interpolation to obtain the start time of ground speed push sweep ; Calculate the start time of ground speed push sweep ,Depend on , , Get the expected posture Euler angle .

[0017] In a second aspect, the present invention further provides a mission planning system for a ground-speed push-sweep satellite, comprising: The first calculation module is used to calculate the expected attitude Euler angles at 1 times the ground speed push sweep and the time when the push sweep reaches the ground point at the geometric center of the surveying area according to the spatial geometric relationship between the satellite, the ground target point and the earth; The second calculation module is used to adopt the control algorithm of the ground-speed push-scan mode to calculate the expected attitude quaternion from the inertial system to the camera coordinate system without drift angle correction when the satellite is pushed at ground-speed, the expected attitude quaternion from the inertial system to the satellite's own system, and the expected total angular velocity of the attitude when the satellite is pushed at ground-speed, and obtain the satellite's current attitude quaternion and the satellite's current attitude angular velocity according to the satellite attitude determination; The third calculation module is used to calculate the start time of the satellite's ground-speed stable push-scanning and the corresponding expected attitude Euler angle, as well as the end time of the ground-speed stable push-scanning and the corresponding expected attitude Euler angle; The fourth calculation module is used to calculate the start time of the satellite's ground speed push-scan and the expected attitude Euler angle.

[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, the method for planning a mission on a ground speed reduction push sweep satellite as described in any one of the above-mentioned methods is implemented.

[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 a mission planning method for a ground-speed push-sweep satellite as described in any one of the above.

[0020] The method and system for planning missions on a ground-speed push-broom satellite provided by the present invention enable the satellite to complete the push-broom imaging mission of the ground area within a specific time period at a speed lower than 1 times the ground speed through a specific ground-speed push-broom mode control algorithm. By accurately calculating the desired attitude of the satellite and the start and end times of the push-broom, the present invention can ensure that the satellite performs the push-broom mission at the desired attitude and speed, significantly improving the flexibility of the mission and the imaging accuracy. This technical solution can meet the special needs of satellites in complex observation missions, adapt to different terrains and observation targets, and achieve more efficient imaging mission planning. 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 flow chart of a method for planning a mission on a ground-descent speed-propelled sweeping satellite provided by the present invention; Figure 2 It is a schematic diagram of the spatial geometric relationship of the ground speed reduction push-sweep provided by the present invention; Figure 3 Schematic diagram of total pointing deviation in the ground speed reduction push-scanning mode provided by the present invention; Figure 4 It is a schematic diagram of the pitch angle deviation of the satellite orbit system in the ground-speed push-scan mode provided by the present invention; Figure 5 It is a schematic diagram of the roll angle deviation of the satellite orbit system in the ground-speed push-scan mode provided by the present invention; Figure 6 It is a schematic diagram of the yaw angle deviation of the satellite orbit system in the ground-speed push-scan mode provided by the present invention; Figure 7 It is a schematic diagram of the satellite X-axis angular velocity deviation in the ground-speed push-scanning mode provided by the present invention; Figure 8 It is a schematic diagram of the satellite Y-axis angular velocity deviation in the ground-speed push-scanning mode provided by the present invention; Fig. 9 It is a schematic diagram of the satellite Z-axis angular velocity deviation in the ground-speed push-scan mode provided by the present invention; Fig.10It is a schematic diagram of the satellite X-axis angular velocity in the ground-speed push-scan mode provided by the present invention; Fig.11 It is a schematic diagram of the satellite Y-axis angular velocity in the ground-speed push-scan mode provided by the present invention; Fig.12 It is a schematic diagram of the Z-axis angular velocity of the satellite in the ground-speed push-scan mode provided by the present invention; Fig.13 It is a structural schematic diagram of a mission planning system for a ground-descent speed push-sweep satellite provided by the present invention; Fig.14 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 planning on-board push-broom missions at reduced ground speed based on the attitude control technology of agile optical remote sensing satellites. The method enables the satellite to complete the push-broom imaging mission of the ground area within a specific time period at a speed lower than 1 times the ground speed through a specific ground-speed reduction push-broom mode control algorithm. By accurately calculating the desired attitude of the satellite and the start and end times of the push-broom, the present invention can ensure that the satellite performs the push-broom mission at the desired attitude and speed, significantly improving the flexibility of the mission and the imaging accuracy. This technical solution can meet the special needs of satellites in complex observation missions, adapt to different terrains and observation targets, and achieve more efficient imaging mission planning.

[0025] Figure 1 FIG. 1 is a flow chart of a method for planning a mission on a ground-speed push-sweep satellite provided by an embodiment of the present invention. Figure 1 As shown, including: Step 100: Calculate the expected attitude Euler angles at 1 times the ground speed and the time when the push sweep reaches the ground point at the geometric center of the surveying area according to the spatial geometric relationship between the satellite, the ground target point and the earth; Step 200: adopting the ground-speed push-scan mode control algorithm, respectively calculating the expected attitude quaternion from the inertial system to the camera coordinate system without drift angle correction when the satellite is at ground-speed push-scan, the expected attitude quaternion from the inertial system to the satellite's own system, and the expected total angular velocity of the attitude when the satellite is at ground-speed push-scan, and obtaining the satellite's current attitude quaternion and the satellite's current attitude angular velocity from the satellite attitude determination; Step 300: Calculate the start time of the satellite's ground-speed-decelerating stable push-scanning and the corresponding expected attitude Euler angle, as well as the end time of the ground-speed-decelerating stable push-scanning and the corresponding expected attitude Euler angle; Step 400: Calculate the satellite's ground-speed push-scan start time and expected attitude Euler angles.

[0026] It should be noted that the main purpose of the present invention is to enable the satellite to push-broom image the ground area at a speed lower than 1 times the ground speed for a period of time, and the Euler angles involved are all in the order of 321. In this mode, when the satellite is in the shadow area, the hyperspectral camera pushes the broom at a constant proportion of the ground speed. First, the expected attitude Euler angles at 1 times the ground speed are calculated by the Newton iteration method, and the time when the push-broom reaches the ground point at the geometric center of the surveying area. Then, a control algorithm for the push-broom mode with reduced ground speed is given. The algorithm calculates the expected attitude, current attitude, expected attitude angular velocity and current attitude angular velocity of the satellite when the push-broom is reduced at the ground speed. Finally, the control algorithm for the push-broom mode with reduced ground speed is used to calculate the start and end times of the stable push-broom with reduced ground speed, and complete the on-board push-broom mission planning.

[0027] Specifically, the process of the embodiment of the present invention includes the following steps: Step 1: Calculate the expected attitude Euler angles at 1x ground speed push sweep , the time when the push-scan reaches the ground point at the geometric center of the survey area , specifically including the following steps: Step 1.1, the expected attitude pitch angle at 1 times ground speed push sweep is , the geometric relationship between the satellite and the ground point of the geometric center of the surveying area is established as follows; like Figure 2 As shown in the figure, when the satellite is pushed to the ground point T at the geometric center of the survey area, the geocentric vector of the ground point T is recorded as , the geocentric vector of satellite S is recorded as , the speed is recorded as , let the yaw angle , Represents the vector from the ground point T to the satellite position S, represents the angular momentum vector, describing the direction of the satellite's orbital plane in inertial space. Then the satellite attitude corresponds to The axis points to:

[0028] The pitch angle when the sweep is set to 1 times the ground speed ,but Axis and satellite's geocentric radius Angle of Radius Vector , and the satellite-target line does not pass through the earth, we have:

[0029] The satellite's passing time function established in step 1.2 is as follows: The conditions for the satellite passing time are:

[0030] The over-the-top time function constructed based on the above formula is:

[0031] Then take the derivative of it and we get:

[0032] when is the time when the satellite passes overhead.

[0033] In step 1.3, Newton's method is used to find the function The zero point of the peak is determined.

[0034] Assume that the initial value of the solution is , during each iteration:

[0035] 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.

[0036] 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, the present invention takes .

[0037] 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.

[0038] According to the satellite's geocentric longitude during the orbit ascending and descending phases (different for prograde and retrograde orbits), 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 orbit segment. , , , and the time of entering and leaving the quasi-visibility segment, and the longitude of the sub-satellite point at the time of entering and leaving the quasi-visibility segment is obtained, that is, , , 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 represent the upper and lower limits of the longitude of the lower point of the star when exiting the quasi-visible period. The value range is limited to .

[0039] Considering the longitude From the jump to The possibility of , L is used to represent the longitude of the satellite's subsatellite point. When L meets the following conditions, it means that the satellite is within the visible area, that is, the prograde and retrograde orbits are different.

[0040]

[0041] Then the corresponding and As a set of feasible initial values, we can substitute Find the solution in .

[0042] Similarly, if (the direct and retrograde orbits are different)

[0043] Then the corresponding and As a set of feasible initial values, we can substitute Find the solution in .

[0044] Otherwise, The orbital period does not have The possibility of making observations does not participate in the solution.

[0045] This screening can also avoid The unreasonableness.

[0046] Finally, the initial value is substituted into the observation equation Solve time .

[0047] Step 1.4: Calculate the time it takes for the satellite to reach 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 . Let the yaw angle , then the satellite's expected attitude coordinate system is:

[0048] The satellite's current orbital coordinate system is:

[0049] The expected attitude Euler angle of the satellite during push sweep is .

[0050] Step 2: The specific process of the ground speed reduction push-broom mode control algorithm is as follows: Step 2.1 Calculate the expected attitude quaternion from the inertial system to the camera coordinate system without drift angle correction when the satellite is pushed down to ground speed: , as follows: In this mode, when the satellite is in the shadow area, the hyperspectral camera pushes and sweeps at a constant proportion of the ground speed. When the hyperspectral system is working, it is the coordinate system of the system to the hyperspectral camera. , we can get the attitude quaternion from the satellite system to the corresponding camera coordinate system .

[0051] 321 Transfer to next The initial expected posture Euler angle at time is Satellite from Starting from the moment, push sweep is performed at a constant ratio of ground speed, assuming the ratio is , that is, the ground speed of the satellite payload optical axis push sweep is ,in Euler angles for satellite attitude The speed at which the optical axis moves toward the ground point during normal ground push-scanning, that is, 1 times the ground speed.

[0052] exist At time , the satellite position is Exercise to , if the satellite is normally scanning the ground, the attitude Euler angle is , the ground point where its optical axis points is If the satellite is pushed down to lower ground speed, the point on the ground that its optical axis points to is It is easy to know that the ground point and At this moment, the satellite position moves to , normal ground sweep, attitude Euler angle is When the axis of light points to the same ground point, find and After obtaining the coordinates, use and The satellite can be obtained by The expected attitude of the moment.

[0053] The coordinates of The position of the satellite at this moment can be directly obtained from the orbit to obtain the position in the J2000 inertial system, and then transferred to the WGS84 fixed system.

[0054] Next ask The coordinates of Time, satellite position Then, the posture Euler angle The ground point can be found Specifically, let The coordinates in the WGS84 fixed system are ( time), The coordinates in the WGS84 fixed system are ( moment), vector The unit vector in the WGS84 Earth-fixed system is ( time), the vector can be calculated from the attitude Euler angle of normal ground sweep Find. ,but

[0055] Because the ground point On the surface of the earth, the earth is considered to be an ellipsoid.

[0056] General Substituting into the above formula, we can get: because Should not wear the earth, Take the smaller of the two. Thus, we can get the ground point Coordinates in the WGS84 Earth-fixed system ( time).

[0057] Depend on Coordinates in the WGS84 Earth-fixed system ( time), get The coordinates in the WGS84 fixed system are still ( time), will The coordinates in the WGS84 fixed system are converted to the inertial system: ( time). Coordinates in the inertial system ( time), the satellite is The vector coordinates of the load direction at the moment . Thus, the satellite can be obtained The inertial system attitude at the moment, that is, the expected attitude quaternion from the inertial system to the camera coordinate system without the drift angle correction is .

[0058] Step 2.2, calculate the expected attitude quaternion from the inertial system to the satellite system: , as follows: First, the posture required in step 2.1 The deviation angle correction is required. According to the deviation angle calculation dynamic link library, .

[0059]

[0060] The expected attitude quaternion from the orbit system to the camera coordinate system after the drift angle correction is:

[0061] Since the attitude quaternion of the satellite system to the corresponding camera coordinate system is , then the expected attitude quaternion from the inertial system to the satellite system is:

[0062] Step 2.3: Calculate the expected total angular velocity of the satellite's attitude during the push-scan process. , as follows: First, solve the relative angular velocity with respect to the orbital system. Since the attitude angle rotation order including the drift angle correction is 3213. The yaw angle of the first rotation around the Zc axis is , ; The second rotation around the Yc axis, the pitch angular velocity Push sweep, and are the desired attitude pitch angles of the current and previous control cycles respectively; the third rotation around the Xc axis, the roll angle Push sweep, and are the expected attitude roll angles of the current and previous control cycles respectively; the fourth rotation around the Zb axis is used to correct the drift angle, and the yaw angular velocity It can be obtained from the drift angle calculation dynamic link library. Wherein, subscript c represents the camera coordinate system, and subscript b represents the satellite body coordinate system. M1 represents the rotation matrix around the X axis, M2 represents the rotation matrix around the Y axis, and M3 represents the rotation matrix around the Z axis. Then the angular velocity of the satellite relative to the orbital system is projected in the camera coordinate system as follows:

[0063] The projection of the satellite's angular velocity relative to the orbital system in the body coordinate system is:

[0064] On the other hand, the angular velocity of the orbital system is , projecting it to the satellite body coordinate system:

[0065] The expected total angular velocity of the satellite is

[0066] Step 2.4, obtain the satellite's current attitude quaternion and the satellite's current attitude angular velocity ; Satellite current attitude quaternion Obtained by attitude determination, the satellite's current attitude angular velocity Obtained by posture determination.

[0067] Step 3: Calculate the start time of the ground speed reduction stable push sweep , expected attitude Euler angle , as follows: The ground speed reduction ratio is known to be The total time for stable push-broom at reduced ground speed is , then the time for the stable push sweep to start is , the satellite is at Figure 2 middle , if the sweep is performed at 1 times the ground speed, the ground point swept at this time is The actual ground point of the sweep is , which is equivalent to the satellite being located at Figure 2 middle The ground point swept at 1 times the ground speed at the time is Using the reduced speed push-sweep control algorithm in step 2, we can calculate , , and further calculate the desired attitude Euler angle ( , , ).

[0068] Step 4: Calculate the end time of the stable push sweep at reduced ground speed , expected attitude Euler angle , as follows: End time of ground speed sweep , the satellite is at Figure 2 middle , if the sweep is performed at 1 times the ground speed, the ground point swept at this time is At the end of the ground speed sweep, the actual ground point of the sweep is , which is equivalent to the satellite being located in the figure The ground point swept at 1 times the ground speed at the time is Similarly, use the step 2 to reduce the speed of the push-sweep control algorithm to calculate , , and further calculate the expected posture Euler angle ( , , ).

[0069] Step 5, calculating the start time of the ground speed push sweep and the expected attitude Euler angle, specifically includes the following two steps: Step 5.1, calculate the pitch angular velocity during the stable push sweep at reduced ground speed , rolling angular velocity , through the pitch angular velocity Interpolation to obtain the maneuvering time when the ground speed reduction push sweep starts .

[0070] When the ground speed is reduced and the sweep is stable, the pitch angular velocity , rolling angular velocity , through the pitch angular velocity Interpolation to obtain the maneuvering time when the ground speed reduction push sweep starts .

[0071] Step 5.2, calculate the start time of ground speed push sweep , expected attitude Euler angle .

[0072] Ground speed push sweep start time , expected attitude Euler angle Depend on , , Available.

[0073] Based on the above embodiment, in order to verify the effectiveness of the present invention in the mission planning of the ground-speed push-sweep satellite of the agile remote sensing optical satellite, the parameters of the satellite on-orbit test are: 1. Target parameters Longitude 139.7° Latitude 35.7° Height: 41m Maximum rolling angle of ground speed sweep: 30° Sun altitude angle: -26° 2. Instruction parameters Ground speed reduction mode starts at 489761498s Imaging start time 489761520s Push sweep time 120s Yaw angle 0° Pitch angle 37.9350° Roll angle 4.3251° Pitch angular velocity -0.46302813° / s Roll angular velocity -0.02335323° / s Assume the ground speed reduction ratio is According to the above parameters, the satellite was tested on-orbit and the ground speed reduction planning and control method was simulated. The results are as follows: The expected Euler angle is (0, 0, 26.164730)°, the total pointing deviation during the ground speed reduction push sweep is 0.25° (3σ), the X-axis attitude stability is 0.002° / s (3σ), the Y-axis attitude stability is 0.001° / s (3σ), and the Z-axis attitude stability is 0.005° / s (3σ).

[0074] like Figures 3 to 12 The simulation results verify that the ground-speed push-broom imaging planning and control method proposed in the present invention can achieve rapid dynamic response and stable adjustment in the satellite attitude control process, and the attitude error gradually converges to a lower level, meeting the imaging accuracy requirements and ensuring the smooth completion of the on-orbit mission.

[0075] The following is a description of the mission planning system for ground-descent speed propulsion and satellite sweeping provided by the present invention. The mission planning system for ground-descent speed propulsion and satellite sweeping described below and the mission planning method for ground-descent speed propulsion and satellite sweeping described above can be referenced to each other.

[0076] Fig.13 FIG. 1 is a schematic diagram of a mission planning system for a ground-speed push-sweep satellite according to an embodiment of the present invention. Fig.13 As shown, it includes: a first calculation module 1301, a second calculation module 1302, a third calculation module 1303 and a fourth calculation module 1304, wherein: The first calculation module 1301 is used to calculate the expected attitude Euler angles and the time when the push-sweep reaches the ground point at the geometric center of the surveying area when the satellite is pushed at 1 times the ground speed according to the spatial geometric relationship between the satellite, the ground target point and the earth; the second calculation module 1302 is used to use the ground speed reduction push-sweep mode control algorithm to calculate the expected attitude quaternion from the inertial system to the camera coordinate system without drift angle correction when the satellite is pushed at the ground speed reduction, the expected attitude quaternion from the inertial system to the satellite's own system, and the expected attitude total angular velocity when the satellite is pushed at the ground speed reduction, and obtain the satellite's current attitude quaternion and the satellite's current attitude angular velocity according to the satellite attitude determination; the third calculation module 1303 is used to calculate the start time of the satellite's ground speed reduction stable push-sweep and the corresponding expected attitude Euler angles, as well as the end time of the ground speed reduction stable push-sweep and the corresponding expected attitude Euler angles; the fourth calculation module 1304 is used to calculate the start time of the satellite's ground speed reduction push-sweep and the expected attitude Euler angles.

[0077] Fig.14 An example of a physical structure diagram of an electronic device is shown in FIG. Fig.14 As shown, the electronic device may include: a processor (processor) 1410, a communication interface (Communications Interface) 1420, a memory (memory) 1430 and a communication bus 1440, wherein the processor 1410, the communication interface 1420, and the memory 1430 communicate with each other through the communication bus 1440. The processor 1410 can call the logic instructions in the memory 1430 to execute the mission planning method on the ground-speed push-sweep satellite, which includes: calculating the expected attitude Euler angles during 1 times the ground speed push-sweep and the time when the push-sweep reaches the ground point at the geometric center of the surveying area according to the spatial geometric relationship between the satellite, the ground target point and the earth; using the ground-speed push-sweep mode control algorithm to calculate the expected attitude quaternion from the inertial system to the camera coordinate system without drift angle correction when the satellite is pushed down to the ground speed, the expected attitude quaternion from the inertial system to the satellite's own system, and the expected attitude total angular velocity when the satellite is pushed down to the ground speed, and determine the satellite's current attitude quaternion and the satellite's current attitude angular velocity based on the satellite attitude; calculating the start time of the satellite's ground-speed stable push-sweep and the corresponding expected attitude Euler angle, as well as the end time of the ground-speed stable push-sweep and the corresponding expected attitude Euler angle; calculating the start time of the satellite's ground-speed push-sweep and the expected attitude Euler angle.

[0078] In addition, the logic instructions in the above-mentioned memory 1430 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, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and 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, Read-Only Memory), a random access memory (RAM, Random Access Memory), a disk or an optical disk.

[0079] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, it is implemented to execute the mission planning method on the ground-speed push-sweep satellite provided by the above-mentioned methods. The method includes: calculating the expected attitude Euler angles and the time of push-sweeping to the ground point at the geometric center of the surveying area at 1 times the ground speed according to the spatial geometric relationship between the satellite, the ground target point and the earth; using the ground-speed push-sweep mode control algorithm to calculate the expected attitude quaternion from the inertial system to the camera coordinate system without drift angle correction when the satellite is pushed down to the ground speed, the expected attitude quaternion from the inertial system to the satellite's own system, and the expected total angular velocity of the attitude when the satellite is pushed down to the ground speed, and obtaining the satellite's current attitude quaternion and the satellite's current attitude angular velocity based on the satellite attitude; calculating the start time of the satellite's ground-speed stable push-sweep and the corresponding expected attitude Euler angles, as well as the end time of the ground-speed stable push-sweep and the corresponding expected attitude Euler angles; calculating the start time of the satellite's ground-speed push-sweep and the expected attitude Euler angles.

[0080] 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.

[0081] 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.

[0082] 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 mission on a ground-speed push-sweep satellite, characterized in that: include: According to the spatial geometric relationship between the satellite, the ground target point and the earth, the expected attitude Euler angle at 1 times the ground speed push-scan and the time when the push-scan reaches the ground point at the geometric center of the surveying area are calculated; The control algorithm of the push-scan mode at ground speed is adopted to calculate the expected attitude quaternion from the inertial system to the camera coordinate system without drift angle correction when the satellite is at ground speed, the expected attitude quaternion from the inertial system to the satellite's own system, and the expected total angular velocity of the attitude when the satellite is at ground speed. The current attitude quaternion and the current attitude angular velocity of the satellite are obtained from the satellite attitude determination. Calculate the start time of the satellite's ground-speed stabilization push-scanning and the corresponding expected attitude Euler angle, as well as the end time of the ground-speed stabilization push-scanning and the corresponding expected attitude Euler angle; Calculate the satellite's ground speed push-scan start time and expected attitude Euler angle.

2. The method for planning a mission on a ground-descent speed sweep satellite according to claim 1, characterized in that: According to the spatial geometric relationship between the satellite, the ground target point and the earth, the expected attitude Euler angles at 1 times the ground speed and the time when the push sweep reaches the ground point at the geometric center of the survey area are calculated, including: Determine the expected attitude pitch angle at 1 times ground speed push sweep as When the satellite is in the center of the survey area, the geometric relationship between the satellite and the ground point is established; According to the geometric relationship between the satellite and the ground point at the geometric center of the surveying area, a satellite over-the-top time function is established; Newton's method is used to find the zero point of the time function of passing the top, and the time when the sweep is pushed to the ground point at the geometric center of the surveying area at 1 times the speed is calculated. ; The time from 1x push-scanning to the ground point at the geometric center of the survey area Calculate the expected attitude Euler angles for 1x ground speed push sweep .

3. The method for planning a ground-descent speed sweep satellite mission according to claim 1, characterized in that: Calculate the expected attitude quaternion from the inertial system to the satellite's own system, including: According to the dynamic link library of the deviation angle calculation, it is obtained : in, is a unit vector, indicating the direction of the rotation axis, is the rotation quaternion corrected by the drift angle; The expected attitude quaternion from the orbit system to the camera coordinate system after the drift angle correction is: Determine the attitude quaternion of the satellite's own system to the corresponding camera coordinate system: , then the expected attitude quaternion from the inertial system to the satellite system is: 。 4. The method for planning a ground-descent speed sweeping satellite mission according to claim 3, characterized in that: Calculate the expected total angular velocity of the satellite's attitude during the push-scan process, including: Determine that the attitude angle rotation sequence including the drift angle correction is 3213, the c-axis is the camera coordinate system, and the b-axis is the satellite body coordinate system; The yaw angle of the first rotation around the Zc axis , , the second rotation around the Yc axis, the pitch angular velocity Push sweep, and They are the desired attitude pitch angle of the current and previous control cycles, the third rotation around the Xc axis, and the roll angle Push sweep, and are the expected attitude roll angles of the current and previous control cycles, the fourth rotation around the Zb axis for drift angle correction, and the yaw angular velocity It can be obtained from the drift angle calculation dynamic link library, and the satellite's relative orbital angular velocity is projected in the camera coordinate system as: M1 represents the rotation matrix around the X axis, M2 represents the rotation matrix around the Y axis, and M3 represents the rotation matrix around the Z axis; 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: is the satellite's ground speed ratio; The expected total angular velocity of the satellite is obtained as: 。 5. The method for planning a ground-descent speed sweep satellite mission according to claim 1, characterized in that: Calculate the start time of the satellite's ground-speed stable push-scanning and the corresponding expected attitude Euler angle, including: Determine the ground speed reduction ratio as The total time for stable push-broom at reduced ground speed is , combined with the 1x speed push sweep to the geometric center ground point of the survey area Get the start time of the ground speed reduction stable push sweep ; Get satellite position The ground sweep point when the sweep is performed at 1 times the ground speed , and the satellite's position The actual ground sweep point at the start of the stable sweep at the time of ground speed reduction , The corresponding time is ; Calculated using the ground speed reduction push-broom control algorithm and , calculate the corresponding expected posture Euler angle .

6. The method for planning a ground-descent speed sweep satellite mission according to claim 5, characterized in that: Calculate the end time of the ground speed stable push sweep and the corresponding expected attitude Euler angle, including: Determine the end time of the stable push sweep at reduced ground speed , the corresponding satellite position for push-scanning at 1 times the ground speed is , the ground push sweep point is ; Get satellite position The actual ground sweep point at the end of the ground speed sweep , The corresponding time is ; Calculated using the ground speed reduction push-broom control algorithm and , calculate the corresponding expected posture Euler angle .

7. The method for planning a ground-descent speed sweep satellite mission according to claim 6, characterized in that: Calculate the satellite's ground speed push-scan start time and expected attitude Euler angle, including: Calculate the pitch rate during steady push sweep at reduced ground speed and rolling angular velocity , through the pitch angular velocity Interpolation to obtain the start time of ground speed push sweep ; Calculate the start time of ground speed push sweep ,Depend on , , Get the expected posture Euler angle .

8. A mission planning system for a ground-speed push-sweep satellite, characterized in that: include: The first calculation module is used to calculate the expected attitude Euler angles at 1 times the ground speed push sweep and the time when the push sweep reaches the ground point at the geometric center of the surveying area according to the spatial geometric relationship between the satellite, the ground target point and the earth; The second calculation module is used to adopt the control algorithm of the ground-speed push-scan mode to calculate the expected attitude quaternion from the inertial system to the camera coordinate system without drift angle correction when the satellite is pushed at ground-speed, the expected attitude quaternion from the inertial system to the satellite's own system, and the expected total angular velocity of the attitude when the satellite is pushed at ground-speed, and obtain the satellite's current attitude quaternion and the satellite's current attitude angular velocity according to the satellite attitude determination; The third calculation module is used to calculate the start time of the satellite's ground-speed stable push-scanning and the corresponding expected attitude Euler angle, as well as the end time of the ground-speed stable push-scanning and the corresponding expected attitude Euler angle; The fourth calculation module is used to calculate the start time of the satellite's ground speed push-scan and the expected attitude Euler angle.

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 method for planning a mission on a ground-speed push-sweep satellite 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 mission on a ground-speed push-sweep satellite as claimed in any one of claims 1 to 7 is implemented.

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