Tracking method and device for surface curve strip target

Abstract

The invention provides a tracking method and device for a surface curve strip target. The method comprises the following steps: fitting ground surface position parameters of a plurality of obtained curve strip targets by using a WGS84 coordinate system to obtain position vectors of the curve strip targets under the WGS84 coordinate system; converting the position vector of the curve strip target in a WGS84 coordinate system to obtain a position vector of the curve strip target in a J2000 inertial system; according to the position vector of the curve strip target under the J2000 inertial system, obtaining a vector of a satellite pointing to the curve strip target; calculating an attitude angle of the satellite pointing to the curve strip target based on the vector of the satellite pointing to the curve strip target; and according to the attitude angle of the satellite pointing to the curve strip target, obtaining an inertial quaternion and an inertial angular velocity of the satellite pointing to the curve strip target so as to track the earth surface curve strip target. According to the scheme, high-efficiency imaging of the earth surface curve strip target can be met.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of spacecraft attitude control, and in particular to a method and device for tracking a curved strip target on the ground surface. Background Art

[0002] High-resolution earth remote sensing observations have put forward diversified requirements for spacecraft imaging modes. The improvement of spacecraft attitude maneuverability and control performance has made diversified imaging of remote sensing satellites possible.

[0003] In related technologies, the imaging method of spacecraft is mainly aimed at stitching imaging of straight strip areas, which can only meet the needs of some conventional missions. For imaging of special narrow surface areas, the imaging method of stitching multiple straight strips is difficult to cover the entire narrow curved surface target. Moreover, when using the imaging method of stitching multiple straight strips, there is generally a long non-imaging time for the transition between strips. In tasks with limited imaging windows, the effectiveness is low.

[0004] Therefore, there is an urgent need to provide a method and device for tracking curved strip targets on the ground. Summary of the invention

[0005] In order to solve the problem that the traditional spacecraft imaging method is not applicable to surface curved strip targets and the imaging efficiency is low, an embodiment of the present invention provides a method and device for tracking surface curved strip targets.

[0006] In a first aspect, an embodiment of the present invention provides a method for tracking a curved strip target on a ground surface, the method comprising:

[0007] The surface position parameters of several curved strip targets are fitted using the WGS84 coordinate system to obtain the position vector of the curved strip target in the WGS84 coordinate system;

[0008] The position vector of the curved strip target in the WGS84 coordinate system is converted to obtain the position vector of the curved strip target in the J2000 inertial system;

[0009] According to the position vector of the curved strip target in the J2000 inertial system, a vector pointing from the satellite to the curved strip target is obtained;

[0010] Calculating the attitude angle and attitude angular rate of the satellite pointing to the curved strip target based on the vector of the satellite pointing to the curved strip target;

[0011] According to the attitude angle and attitude angular rate of the satellite pointing to the curved strip target, the inertial quaternion and inertial angular velocity of the satellite pointing to the curved strip target are obtained to track the curved strip target on the ground surface.

[0012] In a second aspect, an embodiment of the present invention further provides a device for tracking a curved strip target on a ground surface, the device comprising:

[0013] A fitting unit is used to fit the surface position parameters of several curved strip targets obtained by using the WGS84 coordinate system to obtain the position vector of the curved strip target in the WGS84 coordinate system;

[0014] A conversion unit, used for converting the position vector of the curved strip target in the WGS84 coordinate system to obtain the position vector of the curved strip target in the J2000 inertial system;

[0015] A first calculation unit is used to obtain a vector pointing from the satellite to the curved strip target according to the position vector of the curved strip target in the J2000 inertial system;

[0016] A second calculation unit is used to calculate the attitude angle and attitude angular rate of the satellite pointing to the curved strip target based on the vector of the satellite pointing to the curved strip target;

[0017] The tracking unit is used to obtain the inertial quaternion and inertial angular velocity of the satellite pointing to the curved strip target according to the attitude angle and attitude angular rate of the satellite pointing to the curved strip target, so as to track the curved strip target on the surface.

[0018] In a third aspect, an embodiment of the present invention further provides a computing device, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the method described in any embodiment of this specification is implemented.

[0019] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, enables the computer to execute the method described in any embodiment of this specification.

[0020] On the other hand, an embodiment of the present application further provides a computer program product, which includes a computer program. A processor of a computer device reads the computer program from a computer-readable storage medium, and the processor executes the computer program, so that the computer device executes any of the methods described in the above embodiments.

[0021] On the other hand, an embodiment of the present invention further provides a computer program product, including a computer program, which implements the steps of the above-mentioned method when executed by a processor.

[0022] The embodiment of the present invention provides a method and device for tracking a surface curved strip target. First, the position parameters of several obtained curved strip targets are fitted by using a polynomial and expressed by three-dimensional coordinates in the WGS84 coordinate system. Then, the position vector of the curved strip target in the WGS84 coordinate system is converted to the J2000 inertial system. According to the position vector of the curved strip target in the J2000 inertial system, the attitude angle of the satellite pointing to the curved strip target is determined. Finally, based on the attitude angle of the satellite pointing to the curved strip target, the inertial quaternion and the inertial angular velocity of the satellite pointing to the curved strip target are obtained, thereby realizing the tracking of the surface curved strip target. In this way, not only the splicing function of the existing straight strip targets can be covered, but also the high-efficiency imaging of the surface curved strip targets can be satisfied. It can be adapted to any target strip and has great flexibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in 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.

[0024] Figure 1 It is a flow chart of a method for tracking a surface curved strip target provided by one embodiment of the present invention;

[0025] Figure 2 It is a schematic diagram of a method for tracking a curved strip target on a ground surface provided by an embodiment of the present invention;

[0026] Figure 3 is the attitude angle of the three-axis pointing curve strip target of the satellite attitude planning provided by an embodiment of the present invention;

[0027] Figure 4 is the attitude angular rate of the three-axis pointing curve strip target of the satellite attitude planning provided by an embodiment of the present invention;

[0028] Figure 5 is a hardware architecture diagram of a computing device provided by an embodiment of the present invention;

[0029] Figure 6 The present invention is a structural diagram of a tracking device for a curved strip target on a ground surface provided in one embodiment of the present invention. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0031] Please refer to Figure 1 The embodiment of the present invention provides a method for tracking a surface curved strip target, the method comprising:

[0032] Step 100, fitting the surface position parameters of the obtained plurality of curved strip targets using the WGS84 coordinate system to obtain the position vector of the curved strip target in the WGS84 coordinate system;

[0033] Step 102, converting the position vector of the curved strip target in the WGS84 coordinate system to obtain the position vector of the curved strip target in the J2000 inertial system;

[0034] Step 104, obtaining a vector pointing from the satellite to the curved strip target according to the position vector of the curved strip target in the J2000 inertial system;

[0035] Step 106, calculating the attitude angle and attitude angular rate of the satellite pointing to the curved strip target based on the vector of the satellite pointing to the curved strip target;

[0036] Step 108, obtaining the inertial quaternion and inertial angular velocity of the satellite pointing to the curved strip target according to the attitude angle and attitude angular rate of the satellite pointing to the curved strip target, so as to track the curved strip target on the surface.

[0037] In an embodiment of the present invention, firstly, the position parameters of several obtained curved strip targets are fitted by using a polynomial and expressed by three-dimensional coordinates in the WGS84 coordinate system. Then, the position vector of the curved strip target in the WGS84 coordinate system is converted to the J2000 inertial system. According to the position vector of the curved strip target in the J2000 inertial system, the attitude angle of the satellite pointing to the curved strip target is determined. Finally, based on the attitude angle of the satellite pointing to the curved strip target, the inertial quaternion and the inertial angular velocity of the satellite pointing to the curved strip target are obtained, thereby realizing the tracking of the curved strip target on the surface. In this way, not only the splicing function of the existing straight strip targets can be covered, but also the high-efficiency imaging of the curved strip targets on the surface can be satisfied. It can be adapted to any target strip and has great flexibility.

[0038] For step 100:

[0039] In some embodiments, the position vector of the curved strip target in the WGS84 coordinate system is as follows:

[0040]

[0041] In the formula, r x ,r y ,r z are the three-axis positions of the curve strip target in the WGS84 coordinate system, t is the time, A0,…,A n is the x-axis fitting coefficient of the curve strip target, B0,…,B n is the curve strip target y-axis fitting coefficient, C0,…,C n is the z-axis fitting coefficient of the curve strip target.

[0042] In an embodiment of the present invention, a polynomial is used to fit the obtained position parameters of the curved strip target on the surface, and the position vector of the curved strip target is expressed using the WGS84 coordinate system, thereby making the expression of the curved strip target richer, which can effectively be compatible with the existing straight strip stitching imaging and meet the surface curved strip target imaging.

[0043] In the embodiment of the present invention, the fitting coefficient n is greater than or equal to 0, and the number of the fitting coefficients can be specifically determined according to the target expression effect. It can be understood that the more the number of fitting coefficients is, the more conducive it is to the richness of the curve strip target expression.

[0044] For example, in the embodiment of the present invention, the fitting coefficient n is 6. After the surface curve target strip is fitted by a polynomial, the curve target strip x-axis fitting coefficient [A1, ..., A6] = [3910.71, 2.33, 0.073, -0.021, 8.84e-4, 1.06e-5, -8.08e-7], the curve target strip y-axis fitting coefficient [B1, ..., B6] = [48 68.25,-0.16,-0.0629,0.0189,-8.37e-4,-3.825e-6,5.868e-7], curve target strip z-axis fitting coefficient [C1,…,C6]=[1293.83,-6.417,-0.00434,-0.00473,4.85e-4,-1.874e-5,2.569e-7].

[0045] Regarding step 102:

[0046] In some embodiments, the position vector of the curved strip target in the J2000 inertial system is calculated by the following formula:

[0047]

[0048] In the formula, is the position vector of the curved strip target in the J2000 inertial system, C PN is the precession-nutation conversion coefficient matrix at time t, C N1 is the Greenwich sidereal hour angle conversion coefficient matrix at time t, is the position vector of the curve strip target in the WGS84 coordinate system, where:

[0049] In the embodiment of the present invention, since the pointing control of the satellite to the curved strip target on the surface is generally in the inertial system, it is necessary to convert the position vector of the curved strip target in the WGS84 coordinate system to the inertial coordinate system, and when converting the position vector of the curved strip target from the WGS84 coordinate system to the J2000 inertial system, the precession and nutation caused by the rotation or revolution of the earth and the Greenwich sidereal hour angle are considered, which is helpful to ensure the accuracy of the satellite pointing to the curved strip target.

[0050] Regarding step 104:

[0051] In some specific implementations, the vector pointing from the satellite to the curved strip target is calculated using the following formula:

[0052]

[0053] In the formula, is the vector pointing from the satellite to the target of the curved strip, C oi is the conversion coefficient matrix of the satellite from the J2000 inertial system to the orbital system at time t, is the position vector of the satellite in the J2000 inertial system at time t, where r se (1)r se (2)r se ( 3 ) are the unit vectors of the satellite pointing to the curved strip target.

[0054] In the embodiment of the present invention, the vector pointing from the satellite to the curved strip target in the J2000 inertial system can be accurately calculated through the position vector of the satellite in the J2000 inertial system at time t and the position vector of the curved strip target in the J2000 inertial system, thereby facilitating the imaging of the curved strip target.

[0055] Regarding step 106:

[0056] In some embodiments, the attitude angle includes a roll angle, a pitch angle, and a yaw angle of the satellite pointing to the curved strip target, and the attitude angular rate includes a roll angular rate, a pitch angular rate, and a yaw angular rate of the satellite pointing to the curved strip target;

[0057] Step 106 includes:

[0058] Calculating a roll angle and a roll angular rate of the satellite based on a vector pointing from the satellite to the curved strip target;

[0059] Obtaining the pitch angle and pitch angle rate of the satellite according to the roll angle and roll angle rate of the satellite;

[0060] Calculate the difference between the satellite's running speed, the pointing point linear velocity caused by the earth's rotation, and the ground pointing point linear velocity caused by the satellite's attitude angular velocity, and obtain the satellite's relative velocity vector;

[0061] The yaw angle and yaw angle rate of the satellite are obtained according to the relative velocity vector of the satellite.

[0062] In some specific implementations, the roll angle and roll angular rate of the satellite at time t are calculated using the following formula:

[0063]

[0064] In the formula, is the satellite's roll angle at time t, is the satellite's rolling angular rate at time t, is the satellite rolling angle at time t-1, r se (2) and r se (3) are the unit vectors of the satellite pointing to the curved strip target, and ΔT is the control period of the satellite.

[0065] In some specific implementations, the pitch angle and pitch angle rate of the satellite at time t are calculated using the following formula:

[0066] θ r =arcsin(r se (1))

[0067]

[0068] In the formula, θ r is the satellite elevation angle at time t, r se (1) is the unit vector of the satellite pointing to the curved strip target, is the satellite's pitch rate at time t, θ rLst is the elevation angle of the satellite at time t-1.

[0069] In some specific implementations, the relative velocity vector of the satellite is calculated using the following formula:

[0070] v es =v er -v s -vrs

[0071] In the formula, v es is the relative velocity vector of the satellite, v er is the linear velocity of the point caused by the rotation of the earth, v s is the satellite operating speed in this system, v rs The linear velocity of the ground pointing point caused by the satellite attitude angular velocity;

[0072] In some specific implementations, the yaw angle and yaw rate of the satellite at time t are calculated using the following formula:

[0073] ψ r =ψ rLst +Δψ p

[0074]

[0075] In the formula, ψ r is the satellite's yaw angle at time t, ψ rLst is the satellite's yaw angle at time t-1, Δψ p is the increment of the yaw angle from time t-1 to time t, Δψ p =atan2(v es (2),v es (1)), atan2() is the inverse tangent function, v es (m) is the mth element of the relative velocity vector, is the yaw rate of the satellite at time t.

[0076] Depend on Figure 2 It can be seen that in the time period from T1 to T2, in order to realize the real-time tracking of the curved target strip (narrow and long geographical area) of the surface by the spacecraft (satellite), the spacecraft needs to change the attitude angle in real time to realize the precise push-scanning imaging of the curved target strip on the surface. In the embodiment of the present invention, when calculating the yaw angle of the satellite pointing to the curved target strip, by considering the difference between the running speed of the satellite body and the linear velocity of the pointing point caused by the rotation of the earth and the linear velocity of the ground pointing point caused by the satellite attitude angular velocity, the details introduced in the calculation of the yaw angle of the satellite are more comprehensive, which is further conducive to realizing the precise description of the attitude angle of the satellite pointing to the curved target strip (see Figure 3 and Figure 4 ).

[0077] Regarding step 108:

[0078] In some embodiments, step 108 includes:

[0079] Obtaining an attitude conversion coefficient matrix of the satellite in the reference coordinate system relative to the orbital coordinate system according to the roll angle, pitch angle and yaw angle of the satellite pointing to the curved strip target;

[0080] Based on the attitude conversion coefficient matrix of the satellite in the reference coordinate system relative to the orbital coordinate system and the conversion coefficient matrix of the satellite from the J2000 inertial system to the orbital system, the inertial quaternion of the satellite pointing to the curved strip target is calculated;

[0081] Based on the attitude angle of the satellite pointing to the curved strip target, a relative angular velocity of the satellite in the reference coordinate system relative to the orbital coordinate system is obtained;

[0082] The inertial angular velocity of the satellite pointing to the curved strip target is calculated based on the attitude conversion coefficient matrix and the relative angular velocity of the satellite in the reference coordinate system relative to the orbital coordinate system.

[0083] In some specific implementations, the satellite's attitude conversion coefficient matrix C in the reference coordinate system relative to the orbital coordinate system is ro It is calculated as follows:

[0084]

[0085] Wherein, angle2dcm(*) is the attitude angle direction cosine matrix function;

[0086] In some specific embodiments, the inertial quaternion q of the satellite pointing to the curved strip target ri It is calculated as follows:

[0087] q ri =dcm2quat(C ro *C oi )

[0088] In the formula, C oi is the conversion coefficient matrix from the satellite J2000 inertial system to the orbital system at time t, C ro is the attitude conversion coefficient matrix of the satellite in the reference coordinate system relative to the orbital coordinate system, and dcm2quat(*) is the attitude matrix conversion quaternion function;

[0089] In some specific embodiments, the relative angular velocity of the satellite in the reference coordinate system relative to the orbital coordinate system is Calculated by the following formula:

[0090]

[0091] In some specific embodiments, the inertial angular velocity ω of the satellite pointing to the curved strip target ri Calculated by the following formula:

[0092]

[0093] In the formula, ω oi is the satellite orbital angular velocity.

[0094] In the embodiment of the present invention, after the attitude angle of the satellite pointing to the curved strip target is calculated in step 106, the inertial quaternion and inertial angular velocity of the satellite pointing to the curved strip target in the inertial system are obtained by converting from the orbital system to the inertial system using the conversion method in step 108, and the parameters are input into the control system of the satellite to realize the control of the satellite, thereby realizing the tracking and imaging of the curved strip target.

[0095] In summary, it can be seen that the method in the embodiment of the present invention can not only cover the existing straight strip stitching function, but also meet the high-efficiency imaging of surface curved target strips. It is suitable for any target strip, has greater flexibility, and is compatible with existing straight strip stitching imaging and curved strip stitching imaging, and can be applied to earth observation imaging of various remote sensing satellites.

[0096] like Figure 5 , Figure 6 As shown, an embodiment of the present invention provides a device for tracking a curved strip target on the ground. The device embodiment can be implemented by software, or by hardware or a combination of software and hardware. From the hardware level, Figure 5 As shown, it is a hardware architecture diagram of a computing device where a tracking device for a surface curve strip target provided by an embodiment of the present invention is located. Figure 5 In addition to the processor, memory, network interface, and non-volatile memory shown in the figure, the computing device in which the device is located in the embodiment may also generally include other hardware, such as a forwarding chip responsible for processing messages, etc. Taking software implementation as an example, Figure 6 As shown, as a device in a logical sense, the CPU of the computing device in which it is located reads the corresponding computer program in the non-volatile memory into the memory and runs it. This embodiment provides a tracking device for a surface curved strip target, the device comprising:

[0097] A fitting unit 601 is used to fit the surface position parameters of the obtained plurality of curved strip targets using the WGS84 coordinate system to obtain the position vector of the curved strip target in the WGS84 coordinate system;

[0098] A conversion unit 602 is used to convert the position vector of the curved strip target in the WGS84 coordinate system to obtain the position vector of the curved strip target in the J2000 inertial system;

[0099] A first calculation unit 603 is used to obtain a vector pointing from the satellite to the curved strip target according to the position vector of the curved strip target in the J2000 inertial system;

[0100] A second calculation unit 604 is used to calculate the attitude angle and attitude angular rate of the satellite pointing to the curved strip target based on the vector of the satellite pointing to the curved strip target;

[0101] The tracking unit 605 is used to obtain the inertial quaternion and inertial angular velocity of the satellite pointing to the curved strip target according to the attitude angle and attitude angular rate of the satellite pointing to the curved strip target, so as to track the curved strip target on the surface.

[0102] In an embodiment of the present invention, the fitting unit 601 can be used to execute step 100 in the above method embodiment, the conversion unit 602 can be used to execute step 102 in the above method embodiment, the first calculation unit 603 can be used to execute step 104 in the above method embodiment, the second calculation unit 604 can be used to execute step 106 in the above method embodiment, and the tracking unit 605 can be used to execute step 108 in the above method embodiment.

[0103] In one embodiment of the present invention, in the fitting unit 601, the position vector of the curve strip target in the WGS84 coordinate system is as follows:

[0104]

[0105] In the formula, r x ,r y ,r z are the three-axis positions of the curve strip target in the WGS84 coordinate system, t is the time, A0,…,A n is the x-axis fitting coefficient of the curve strip target, B0,…,B n is the curve strip target y-axis fitting coefficient, C0,…,C n is the z-axis fitting coefficient of the curve strip target.

[0106] In one embodiment of the present invention, in the conversion unit 602, the position vector of the curved strip target in the J2000 inertial system is calculated by the following formula:

[0107]

[0108] In the formula, is the position vector of the curved strip target in the J2000 inertial system, CPN is the precession-nutation conversion coefficient matrix at time t, CN1 is the Greenwich sidereal hour angle conversion coefficient matrix at time t, is the position vector of the curve strip target in the WGS84 coordinate system, where:

[0109] In one embodiment of the present invention, the attitude angle includes a roll angle, a pitch angle and a yaw angle of the satellite pointing to the curved strip target, and the attitude angular rate includes a roll angular rate, a pitch angular rate and a yaw angular rate of the satellite pointing to the curved strip target;

[0110] The second calculation unit 603 calculates the attitude angle and attitude angular rate of the satellite pointing to the curved strip target based on the vector of the satellite pointing to the curved strip target, and is used to perform the operation:

[0111] Calculating a roll angle and a roll angular rate of the satellite based on a vector pointing from the satellite to the curved strip target;

[0112] Obtaining the pitch angle and pitch angle rate of the satellite according to the roll angle and roll angle rate of the satellite;

[0113] Calculate the difference between the satellite's running speed, the pointing point linear velocity caused by the earth's rotation, and the ground pointing point linear velocity caused by the satellite's attitude angular velocity, and obtain the satellite's relative velocity vector;

[0114] The yaw angle and yaw angle rate of the satellite are obtained according to the relative velocity vector of the satellite.

[0115] In one embodiment of the present invention, the tracking unit 604 obtains the inertial quaternion and inertial angular velocity of the satellite pointing to the curved strip target according to the attitude angle of the satellite pointing to the curved strip target, and is used to perform the following operations:

[0116] Obtaining an attitude conversion coefficient matrix of the satellite in the reference coordinate system relative to the orbital coordinate system according to the roll angle, pitch angle and yaw angle of the satellite pointing to the curved strip target;

[0117] Based on the attitude conversion coefficient matrix of the satellite in the reference coordinate system relative to the orbital coordinate system and the conversion coefficient matrix of the satellite from the J2000 inertial system to the orbital system, the inertial quaternion of the satellite pointing to the curved strip target is calculated;

[0118] Based on the attitude angle of the satellite pointing to the curved strip target, a relative angular velocity of the satellite in the reference coordinate system relative to the orbital coordinate system is obtained;

[0119] The inertial angular velocity of the satellite pointing to the curved strip target is calculated based on the attitude conversion coefficient matrix and the relative angular velocity of the satellite in the reference coordinate system relative to the orbital coordinate system.

[0120] It is to be understood that the structure illustrated in the embodiment of the present invention does not constitute a specific limitation on a tracking device for a surface curved strip target. In other embodiments of the present invention, a tracking device for a surface curved strip target may include more or fewer components than shown in the figure, or combine some components, or split some components, or arrange the components differently. The components shown in the figure may be implemented in hardware, software, or a combination of software and hardware.

[0121] The information interaction, execution process and other contents between the modules in the above-mentioned device are based on the same concept as the embodiment of the method of the present invention. For the specific contents, please refer to the description in the embodiment of the method of the present invention, and no further description is given here.

[0122] An embodiment of the present invention further provides a computing device, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, a method for tracking a surface curve strip target in any embodiment of the present invention is implemented.

[0123] An embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the processor executes a method for tracking a surface curve strip target in any embodiment of the present invention.

[0124] Specifically, a system or device equipped with a storage medium can be provided, on which software program code that implements the functions of any of the above-mentioned embodiments is stored, and a computer (or CPU or MPU) of the system or device can be enabled to read and execute the program code stored in the storage medium.

[0125] In this case, the program code itself read from the storage medium can realize the function of any one of the above-mentioned embodiments, and thus the program code and the storage medium storing the program code constitute a part of the present invention.

[0126] The storage medium embodiments for providing the program code include a floppy disk, a hard disk, a magneto-optical disk, an optical disk (such as CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD+RW), a magnetic tape, a non-volatile memory card, and a ROM. Alternatively, the program code can be downloaded from a server computer by a communication network.

[0127] In addition, it should be clear that the functions of any of the above embodiments can be implemented not only by executing the program code read by the computer, but also by enabling an operating system operating on the computer to complete part or all of the actual operations based on instructions from the program code.

[0128] In addition, it can be understood that the program code read from the storage medium is written to a memory provided in an expansion board inserted into the computer or to a memory provided in an expansion module connected to the computer, and then based on the instructions of the program code, a CPU installed on the expansion board or expansion module is enabled to perform part or all of the actual operations, thereby realizing the functions of any of the above-mentioned embodiments.

[0129] An embodiment of the present application also provides a computer-readable storage medium, on which is stored at least one instruction, at least one program, code set or instruction set, and the at least one instruction, at least one program, code set or instruction set is loaded and executed by a processor to implement a method for tracking a surface curve strip target provided by the above-mentioned method embodiments.

[0130] It should be noted that, in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0131] A person of ordinary skill in the art can understand that all or part of the steps of implementing the above method embodiments can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above method embodiments; and the aforementioned storage medium includes: ROM, RAM, magnetic disk or optical disk, etc., various media that can store program codes.

[0132] 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 tracking a curved strip target on a ground surface, characterized in that: include: The surface position parameters of several curved strip targets are fitted using the WGS84 coordinate system to obtain the position vector of the curved strip target in the WGS84 coordinate system; The position vector of the curved strip target in the WGS84 coordinate system is converted to obtain the position vector of the curved strip target in the J2000 inertial system; According to the position vector of the curved strip target in the J2000 inertial system, a vector pointing from the satellite to the curved strip target is obtained; Calculating the attitude angle and attitude angular rate of the satellite pointing to the curved strip target based on the vector of the satellite pointing to the curved strip target; According to the attitude angle and attitude angular rate of the satellite pointing to the curved strip target, the inertial quaternion and inertial angular velocity of the satellite pointing to the curved strip target are obtained to track the curved strip target on the ground surface.

2. The method according to claim 1, characterized in that The position vector of the curved strip target in the WGS84 coordinate system is as follows: In the formula, r x ,r y ,r z are the three-axis positions of the curve strip target in the WGS84 coordinate system, t is the time, A0,…,A n is the x-axis fitting coefficient of the curve strip target, B0,…,B n is the curve strip target y-axis fitting coefficient, C0,…,C n is the z-axis fitting coefficient of the curve strip target.

3. The method according to claim 1, characterized in that The position vector of the curved strip target in the J2000 inertial system is calculated by the following formula: In the formula, is the position vector of the curved strip target in the J2000 inertial system, CPN is the precession-nutation conversion coefficient matrix at time t, CN1 is the Greenwich sidereal hour angle conversion coefficient matrix at time t, is the position vector of the curve strip target in the WGS84 coordinate system, where:

4. The method according to claim 1, characterized in that: The vector pointing from the satellite to the curved strip target is calculated by the following formula: In the formula, is the vector pointing from the satellite to the target of the curved strip, C oi is the conversion coefficient matrix of the satellite from the J2000 inertial system to the orbital system at time t, is the position vector of the satellite in the J2000 inertial system at time t, where 5. The method according to claim 1, characterized in that The attitude angle includes the roll angle, pitch angle and yaw angle of the satellite pointing to the curved strip target, and the attitude angular rate includes the roll angular rate, pitch angular rate and yaw angular rate of the satellite pointing to the curved strip target; The step of calculating the attitude angle and attitude angular rate of the satellite pointing to the curved strip target based on the vector of the satellite pointing to the curved strip target comprises: Calculating a roll angle and a roll angular rate of the satellite based on a vector pointing from the satellite to the curved strip target; Obtaining the pitch angle and pitch angle rate of the satellite according to the roll angle and roll angle rate of the satellite; Calculate the difference between the satellite's running speed, the pointing point linear velocity caused by the earth's rotation, and the ground pointing point linear velocity caused by the satellite's attitude angular velocity, and obtain the satellite's relative velocity vector; The yaw angle and yaw angle rate of the satellite are obtained according to the relative velocity vector of the satellite.

6. The method according to claim 5, characterized in that The step of obtaining the inertial quaternion and the inertial angular velocity of the satellite pointing to the curved strip target according to the attitude angle of the satellite pointing to the curved strip target comprises: Obtaining an attitude conversion coefficient matrix of the satellite in the reference coordinate system relative to the orbital coordinate system according to the roll angle, pitch angle and yaw angle of the satellite pointing to the curved strip target; Based on the attitude conversion coefficient matrix of the satellite in the reference coordinate system relative to the orbital coordinate system and the conversion coefficient matrix of the satellite from the J2000 inertial system to the orbital system, the inertial quaternion of the satellite pointing to the curved strip target is calculated; Based on the attitude angle of the satellite pointing to the curved strip target, a relative angular velocity of the satellite in the reference coordinate system relative to the orbital coordinate system is obtained; The inertial angular velocity of the satellite pointing to the curved strip target is calculated based on the attitude conversion coefficient matrix and the relative angular velocity of the satellite in the reference coordinate system relative to the orbital coordinate system.

7. A tracking device for a curved strip target on the ground surface, characterized in that: include: A fitting unit is used to fit the surface position parameters of several curved strip targets obtained by using the WGS84 coordinate system to obtain the position vector of the curved strip target in the WGS84 coordinate system; A conversion unit, used for converting the position vector of the curved strip target in the WGS84 coordinate system to obtain the position vector of the curved strip target in the J2000 inertial system; A first calculation unit is used to obtain a vector pointing from the satellite to the curved strip target according to the position vector of the curved strip target in the J2000 inertial system; A second calculation unit is used to calculate the attitude angle and attitude angular rate of the satellite pointing to the curved strip target based on the vector of the satellite pointing to the curved strip target; The tracking unit is used to obtain the inertial quaternion and inertial angular velocity of the satellite pointing to the curved strip target according to the attitude angle and attitude angular rate of the satellite pointing to the curved strip target, so as to track the curved strip target on the surface.

8. A computing device, comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the method according to any one of claims 1 to 6 is implemented.

9. A computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, causes the computer to execute the method according to any one of claims 1 to 6.

10. A computer program product, characterized in that The method comprises a computer program, wherein when the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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