Space target tracking method and device using linear array camera push-broom imaging

Abstract

The invention provides a space target tracking method and device using linear array camera push-broom imaging. The method comprises the following steps: calculating a velocity vector and a position vector of a satellite pointing to a space target at a center intersection moment according to position vectors and velocity vectors of the satellite and the space target in an inertial system; obtaining an attitude angle of the satellite pointing to the space target at the center intersection moment based on the position vector of the satellite pointing to the space target; according to the position vector and the relative velocity vector of the satellite pointing to the space target, the attitude angle and the Euler axis of satellite push-broom are obtained; obtaining an inertial quaternion and an inertial angular velocity of the space target at the current moment based on an attitude angle of the satellite pointing to the space target, an attitude angle of satellite push-broom and an Euler axis; and according to the inertial quaternion and the inertial angular velocity of the space target, calculating the attitude control moment of the satellite at the current moment so as to drive the satellite to track the space target in real time. According to the scheme, high-resolution imaging of the space target can be realized.

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 space target using push-scan imaging of a linear array camera. Background Art

[0002] When a remote sensing satellite equipped with a linear array camera realizes imaging observation of space targets, it needs to have a certain speed in the push-sweep direction. However, the current imaging method of remote sensing satellites equipped with linear array cameras is mainly aimed at the splicing imaging of ground target points and straight strip areas, which is difficult to meet the needs of push-sweep imaging of space targets. In addition, for ground target imaging, the calculation method of the target drift angle using the optical axis pointing to the target and the yaw attitude is no longer applicable to space targets. It is impossible to achieve the push-sweep direction perpendicular to the line of sight direction, and it is impossible to achieve the requirement of pushing the target at a specified speed.

[0003] Therefore, there is an urgent need to provide a method and device for tracking space targets using push-scan imaging of a linear array camera. Summary of the invention

[0004] In order to solve the problem that the conventional imaging method of remote sensing satellites equipped with linear array cameras is difficult to meet the demand for push-broom imaging of space targets, an embodiment of the present invention provides a method and device for tracking space targets using push-broom imaging of linear array cameras.

[0005] In a first aspect, an embodiment of the present invention provides a method for tracking a space target using push-scan imaging of a linear array camera, the method comprising:

[0006] Obtain the position vector and velocity vector of the satellite and the space target in the J2000 inertial system at the center intersection time; wherein the center intersection time is the intermediate time from the start to the end of the push-scan imaging of the space target by the satellite;

[0007] According to the position vectors of the satellite and the space target in the J2000 inertial system, the position vector of the satellite pointing to the space target in the J2000 inertial system at the time of center intersection is calculated;

[0008] Based on the position vector of the satellite pointing to the space target, obtaining the attitude angle of the satellite pointing to the space target at the time of center intersection;

[0009] According to the velocity vectors of the satellite and the space target in the J2000 inertial system, a relative velocity vector of the satellite pointing to the space target in the J2000 inertial system at the time of center intersection is calculated;

[0010] According to the position vector and relative velocity vector of the satellite pointing to the space target, the attitude angle and Euler axis of the satellite push-scan are obtained;

[0011] Based on the attitude angle of the satellite pointing to the space target at the center intersection moment, the attitude angle of the satellite push-scan and the Euler axis, the inertial quaternion and the inertial angular velocity of the space target at the current moment are obtained;

[0012] According to the inertial quaternion and inertial angular velocity of the space target, the attitude control torque of the satellite at the current moment is calculated to drive the satellite to track the space target in real time.

[0013] In a second aspect, an embodiment of the present invention further provides a space target tracking device using push-scan imaging of a linear array camera, the device comprising:

[0014] An acquisition unit, used to acquire the position vector and velocity vector of the satellite and the space target in the J2000 inertial system at the center intersection time; wherein the center intersection time is the intermediate time from the start to the end of the push-scan imaging of the space target by the satellite;

[0015] A first calculation unit is used to calculate the position vector of the satellite pointing to the space target in the J2000 inertial system at the time of center intersection according to the position vectors of the satellite and the space target in the J2000 inertial system;

[0016] A second calculation unit is used to obtain an attitude angle of the satellite pointing to the space target at the time of center intersection based on the position vector of the satellite pointing to the space target;

[0017] A third calculation unit is used to calculate the velocity vector of the satellite pointing to the space target in the J2000 inertial system at the time of center intersection according to the relative velocity vector of the satellite and the space target in the J2000 inertial system;

[0018] A fourth calculation unit is used to obtain the attitude angle and Euler axis of the satellite push-scan according to the position vector and relative velocity vector of the satellite pointing to the space target;

[0019] A fifth calculation unit is used to obtain the inertial quaternion and inertial angular velocity of the space target at the current moment based on the attitude angle of the satellite pointing to the space target at the central intersection moment, the attitude angle of the satellite push-scan and the Euler axis;

[0020] The tracking unit is used to calculate the attitude control torque of the satellite at the current moment according to the inertial quaternion and inertial angular velocity of the space target, so as to drive the satellite to track the space target in real time.

[0021] 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.

[0022] 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.

[0023] 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.

[0024] 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.

[0025] The embodiment of the present invention provides a space target tracking method and device using push-broom imaging of a linear array camera, wherein the linear array camera carried by a satellite performs push-broom imaging of a space target, firstly, the intermediate time from the start of push-broom imaging of the space target by the satellite to the end is determined as the center intersection time, and the attitude angle and Euler axis of the satellite push-brooming the space target at the center intersection time are calculated, and then based on the attitude angle and Euler axis of the satellite push-brooming the space target at the center intersection time, recursive calculation is performed within the entire period of intersection between the satellite and the space target, so as to obtain the attitude control torque of the satellite in the inertial system at any time, and finally, the satellite is driven by the above-mentioned attitude control torque to achieve tracking of the space target. The push-broom method in the embodiment of the present invention can calculate the target attitude of the linear array camera push-broom according to the real-time orbital characteristics of the space target, greatly reduce the angular velocity of the star during push-brooming, and achieve high-resolution imaging of the space target. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] 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.

[0027] Figure 1 is a flow chart of a space target tracking method using push-scan imaging of a linear array camera provided by an embodiment of the present invention;

[0028] Figure 2 is a schematic diagram of a satellite performing push-broom imaging of a space target provided by an embodiment of the present invention;

[0029] Figure 3is the three-axis attitude angle of the satellite when push-broom imaging of a space target is provided by an embodiment of the present invention; in the figure, is the roll angle of the satellite pointing to the space target, θ r is the elevation angle of the satellite pointing to the space target, ψ r The yaw angle of the satellite push-scan in the J2000 inertial system;

[0030] Figure 4 is a hardware architecture diagram of a computing device provided by an embodiment of the present invention;

[0031] Figure 5 It is a structural diagram of a space target tracking device using push-scan imaging of a linear array camera provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0032] 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.

[0033] Please refer to Figure 1 The embodiment of the present invention provides a space target tracking method using push-scan imaging of a linear array camera, the method comprising:

[0034] Step 100, obtaining the position vector and velocity vector of the satellite and the space target in the J2000 inertial system at the center intersection time; wherein the center intersection time is the intermediate time from the start to the end of the push-scan imaging of the space target by the satellite;

[0035] Step 102, calculating the position vector of the satellite pointing to the space target in the J2000 inertial system at the time of center intersection according to the position vectors of the satellite and the space target in the J2000 inertial system;

[0036] Step 104, based on the position vector of the satellite pointing to the space target, obtain the attitude angle of the satellite pointing to the space target at the time of center intersection;

[0037] Step 106, calculating the relative velocity vector of the satellite pointing to the space target in the J2000 inertial system at the time of center intersection according to the velocity vectors of the satellite and the space target in the J2000 inertial system;

[0038] Step 108, obtaining the attitude angle and Euler axis of the satellite push-scan according to the position vector and relative velocity vector of the satellite pointing to the space target;

[0039] Step 110, based on the attitude angle of the satellite pointing to the space target at the center intersection moment, the attitude angle of the satellite push-scan and the Euler axis, obtain the inertial quaternion and inertial angular velocity of the space target at the current moment;

[0040] Step 112, calculating the attitude control torque of the satellite at the current moment according to the inertial quaternion and inertial angular velocity of the space target, so as to drive the satellite to track the space target in real time.

[0041] In an embodiment of the present invention, a linear array camera carried by a satellite is used to push-broom image a space target. First, the intermediate time from the start to the end of the satellite push-broom imaging of the space target is determined as the center intersection time, and the attitude angle and Euler axis of the satellite push-brooming the space target at the center intersection time are calculated. Then, based on the attitude angle and Euler axis of the satellite push-brooming the space target at the center intersection time, a recursive calculation is performed within the entire period of intersection between the satellite and the space target, thereby obtaining the attitude control torque of the satellite in the inertial system at any time. Finally, the satellite is driven by the above attitude control torque to achieve tracking of the space target. The push-broom method in the embodiment of the present invention can calculate the target attitude of the linear array camera push-broom according to the real-time orbital characteristics of the space target, greatly reduce the angular velocity of the star during push-brooming, and achieve high-resolution imaging of the target.

[0042] For step 100:

[0043] In the embodiment of the present invention, Figure 2 As shown in the figure, the start time of the satellite push-broom imaging of the space target is t ms , the end time is t me , then the central intersection time t a is: t a =(t ms +t me ) / 2; by the central intersection time t a The satellite calculates the attitude angle and velocity vector of the space target, and then recursively calculates the inertial quaternion and inertial angular velocity of the space target in the orbital system based on the center intersection moment, which helps to reduce the error caused by the orbital system and enhance the accuracy of the satellite's tracking and control of the space target.

[0044] Regarding step 102:

[0045] In some implementations, step 102 includes:

[0046] Calculating the relative distance between the satellite and the space target at the time of center intersection according to the position vectors of the satellite and the space target in the J2000 inertial system;

[0047] Based on the position vectors of the satellite and the space target in the J2000 inertial system and the relative distance between the satellite and the space target, a unit vector of the satellite pointing to the space target at the time of center intersection is obtained;

[0048] According to the unit vector of the satellite pointing to the space target and the conversion coefficient matrix of the satellite from the J2000 inertial system to the orbital system, the position vector of the satellite pointing to the space target in the J2000 inertial system at the time of central intersection is obtained.

[0049] In some specific embodiments, the central intersection time t a The relative distance L between the satellite and the space target is calculated by the following formula:

[0050]

[0051] In the formula, t a The position vector of the space target in the J2000 inertial system at the moment, t a The position vector of the satellite J2000 inertial system at this moment;

[0052] Central intersection time t a Unit vector of the satellite pointing to the space target Calculated by the following formula:

[0053]

[0054] Furthermore, the central intersection time t a Position vector of satellite pointing to space target in J2000 inertial system Calculated by the following formula:

[0055]

[0056] In the formula, C oi t a The conversion coefficient array from the inertial system of satellite J2000 to the orbital system at this time.

[0057] In an embodiment of the present invention, by first calculating the relative distance between the satellite body and the space target at the center intersection moment, and using the relative distance and the position vectors of the satellite and the space target at the center intersection moment, it is helpful to accurately determine the position vector of the satellite pointing to the space target at the center intersection moment.

[0058] Regarding step 104:

[0059] In some embodiments, the attitude angle includes the roll angle and pitch angle of the satellite pointing to the space target at the center intersection moment:

[0060] The attitude angle of the satellite pointing to the space target at the center intersection moment is calculated by the following formula:

[0061]

[0062] In the formula, is the roll angle of the satellite pointing to the space target, θ r is the elevation angle of the satellite pointing to the space target, is the position vector of the satellite pointing to the space target.

[0063] Regarding step 106:

[0064] In some implementations, step 106 includes:

[0065] According to the velocity vectors of the satellite and the space target in the J2000 inertial system, a vertical line of sight component of the space target relative to the satellite velocity is obtained;

[0066] Based on the vertical line of sight component, satellite orbit altitude, earth radius constant and satellite orbit angular velocity, obtaining the relative velocity of the satellite and the space target being collinear;

[0067] Based on the vertical line-of-sight component of the space target relative to the satellite velocity and the relative velocity of the satellite and the space target being collinear, a relative velocity vector of the satellite pointing to the space target in the J2000 inertial system at the time of central intersection is obtained.

[0068] In some specific embodiments, the vertical line-of-sight component of the space target relative to the satellite velocity Calculated by the following formula:

[0069]

[0070] In the formula, t a The velocity vector of the satellite in the J2000 inertial system at this moment, t a The velocity vector of the space target in the J2000 inertial system at the moment, t a The unit vector of the satellite pointing to the space target at the moment, (·) is the vector dot product function;

[0071] The relative speed of the satellite and the space target relative speed are collinear Calculated by the following formula:

[0072]

[0073] Where ω0 is the satellite orbital angular velocity, R eis the Earth radius constant, H is the satellite orbit height;

[0074] The relative velocity vector of the satellite pointing to the space target in the J2000 inertial system at the time of central intersection (i.e., the synthetic collinear push-broom velocity of the satellite and the space target being collinear) Calculated by the following formula:

[0075]

[0076] In an embodiment of the present invention, when determining the push-scan speed of a satellite for a space target, the vertical line-of-sight component of the space target's speed relative to the satellite and the relative speed between the satellite and the space target are considered, and the space target is push-scanned at a push-scan speed synthesized from the two. In this way, the push-scan direction of the satellite can be opposite to the speed direction of the space target relative to its own satellite, that is, "head-on scanning", thereby greatly reducing the angular velocity of the star during push-scanning and achieving high-resolution imaging of the space target.

[0077] Regarding step 108:

[0078] In some embodiments, step 108 includes:

[0079] According to the attitude angle of the satellite pointing to the space target and the relative speed of the space target and the relative speed between the satellite and the space target, the yaw angle of the satellite push-scan in the J2000 inertial system is obtained;

[0080] According to the relative distance between the satellite and the space target, the position vector and relative velocity vector of the satellite pointing to the space target, the angular velocity of the satellite push-scan in the J2000 inertial system is calculated;

[0081] Based on the attitude angle of the satellite pointing to the space target, the yaw angle of the satellite push-scan in the J2000 inertial system and the angular velocity of the satellite push-scan in the J2000 inertial system, the attitude angular velocity of the satellite push-scan in the J2000 inertial system is obtained;

[0082] Based on the attitude angular velocity of the satellite push-broom in the J2000 inertial system, the Euler axis of the satellite push-broom is obtained.

[0083] In some specific implementations, the yaw angle of the satellite push-scan in the J2000 inertial system is calculated as follows:

[0084] Based on the relative velocity of the space target in line with the relative velocity, the conversion coefficient matrix from the satellite J2000 inertial system to the orbital system, and the attitude angle of the satellite pointing to the space target, the expression of the push-broom velocity in the orbital system Vr is obtained:

[0085]

[0086] The push-broom velocity expression in the orbital system is converted to obtain the satellite push-broom yaw angle ψ in the J2000 inertial system. r :

[0087]

[0088] Where Vr is the push-broom velocity in the orbital system, V r =(V r (1), V r (2), V r (3)), Angle2DCM() is the function of converting attitude angle to direction cosine matrix, is the roll angle of the satellite pointing to the space target, θ r is the elevation angle of the satellite pointing to the space target.

[0089] Considering that the satellite pointing to the space target is usually determined by two factors, position pointing and speed pointing, the attitude angle (roll angle and pitch angle) of the satellite pointing to the space target calculated in step 104 can ensure that the satellite can point to the space target at the center intersection moment. Since the space target and the satellite are in a real-time state of motion, in order to enable the satellite to point to the space target in real time, in the embodiment of the present invention, the yaw angle is further introduced to control the satellite (such as Figure 3 As shown in the figure, the space target is associated with the speed relative to the satellite during the yaw angle calculation process, which is beneficial to ensure that the speed and direction of the satellite body and the space target are close in real time, which is beneficial to achieve real-time tracking and high-resolution imaging of the space target.

[0090] In some specific implementations, the angular velocity ω of the satellite in the J2000 inertial frame is ai Calculated by the following formula:

[0091]

[0092] Where, cross() is the vector cross product function;

[0093] Satellite push-scan attitude angular velocity ω in the J2000 inertial system aiB Calculated by the following formula:

[0094]

[0095] The inertial quaternion q of the satellite at the beginning of push-scan in the J2000 inertial system aiB Calculated by the following formula:

[0096]

[0097] In some specific embodiments, the Euler axis e of the satellite push-scan in the J2000 inertial system is aiB =[e ax e ay e az ] is calculated by the following formula:

[0098]

[0099] Regarding step 110:

[0100] In some embodiments, step 110 includes:

[0101] The angular velocity ω of the satellite in the J2000 inertial system is ai Determined as the inertial angular velocity ω of the space target at the current time t ri ;

[0102] Based on the angular velocity of the satellite push-scan in the J2000 inertial system and the difference between the current moment and the center intersection moment, the attitude angle of the space target at the current moment is obtained;

[0103] Based on the attitude angle of the space target, the attitude angle of the satellite pointing to the space target, the Euler axis and attitude angle of the satellite push-scan, the inertial angular velocity of the space target at the current moment is obtained.

[0104] In some specific implementations, the attitude angle x of the space target at the current moment t is r Calculated by the following formula:

[0105]

[0106] The inertial angular velocity q of the space target at the current time t ri Calculated by the following formula:

[0107]

[0108] In the formula, q aiB It is the inertial quaternion of the satellite at the beginning of push-scanning.

[0109] Since the motion posture of the space target is different at different times, in order to achieve real-time tracking of the space target, the satellite also needs to change its posture in real time. Therefore, in the embodiment of the present invention, the center intersection time is taken as the midpoint, and the current time is extrapolated to the center intersection time before and after, so that the attitude angle of the space target at each time t and the quaternion of the space target in the inertial system can be obtained. The satellite is controlled by the quaternion in the inertial system to achieve tracking and imaging of the space target.

[0110] Regarding step 112:

[0111] In some embodiments, step 112 includes:

[0112] Obtaining the attitude control value of the satellite according to the inertial quaternion and the attitude measurement quaternion of the space target;

[0113] Subtracting the inertial angular velocity of the space target from the angular velocity measurement to obtain the angular velocity control amount of the satellite;

[0114] The attitude control torque of the satellite is calculated according to the attitude control amount and the angular velocity control amount of the satellite.

[0115] In some specific implementations, the attitude control amount Δθ of the satellite is calculated by the following formula:

[0116]

[0117] Where qbi is the satellite attitude measurement quaternion, qri is the inertial quaternion of the space target, Δq b (1:3) is the error quaternion Δq b The first 3 elements of ;

[0118] The satellite's angular velocity control value Δω is calculated by the following formula:

[0119] Δω=ω ri -ω bi

[0120] In the formula, ω bi is the satellite angular velocity measurement value.

[0121] Furthermore, the attitude control torque of the satellite is calculated by the following formula:

[0122]

[0123] In the formula, I sat is the inertia of the whole star, is the satellite three-axis target inertial angular acceleration, is the satellite three-axis target inertial angular acceleration, ω bi is the angular velocity measurement value of the satellite control system, Δθ is the satellite three-axis attitude control value, Δω is the satellite three-axis angular velocity control value, k satp , k sati and k satd are controller parameters, τ b is the attitude control torque of the satellite.

[0124] In an embodiment of the present invention, the attitude control amount and angular velocity control amount of the satellite are obtained by calculating the attitude difference and angular velocity difference between the satellite and the space target, and the above control amounts are used as input parameters of the satellite attitude controller to obtain the attitude control torque of the satellite to drive the satellite to push-broom imaging of the space target, thereby realizing the satellite's push-broom imaging pointing tracking of the space target.

[0125] In summary, the push-broom imaging method in this embodiment can calculate the target attitude of the linear array camera push-broom according to the real-time orbital characteristics of the space target, greatly reduce the angular velocity of the star during push-broom, and realize push-broom imaging of any space target, thus meeting the increasing imaging mode requirements of remote sensing satellites.

[0126] like Figure 4 , Figure 5 As shown, an embodiment of the present invention provides a space target tracking device using push-scan imaging of a linear array camera. The device embodiment can be implemented by software, or by hardware or a combination of software and hardware. From the hardware level, Figure 4 FIG. 1 is a hardware architecture diagram of a computing device in which a space target tracking device using a linear array camera push-scan imaging is provided in an embodiment of the present invention. Figure 4 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 5 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 space target tracking device using push-scan imaging of a linear array camera, and the device includes:

[0127] The acquisition unit 501 is used to acquire the position vector and velocity vector of the satellite and the space target in the J2000 inertial system at the center intersection time; wherein the center intersection time is the intermediate time from the start to the end of the push-scan imaging of the space target by the satellite;

[0128] The first calculation unit 502 is used to calculate the position vector of the satellite pointing to the space target in the J2000 inertial system at the time of center intersection according to the position vectors of the satellite and the space target in the J2000 inertial system;

[0129] The second calculation unit 503 is used to obtain the attitude angle of the satellite pointing to the space target at the time of center intersection based on the position vector of the satellite pointing to the space target;

[0130] The third calculation unit 504 is used to calculate the relative velocity vector of the satellite pointing to the space target in the J2000 inertial system at the time of center intersection according to the velocity vectors of the satellite and the space target in the J2000 inertial system;

[0131] A fourth calculation unit 505 is used to obtain the attitude angle and Euler axis of the satellite push-scan according to the position vector and relative velocity vector of the satellite pointing to the space target;

[0132] A fifth calculation unit 506 is used to obtain the inertial quaternion and inertial angular velocity of the space target at the current moment based on the attitude angle of the satellite pointing to the space target at the central intersection moment, the attitude angle of the satellite push-scan and the Euler axis;

[0133] The tracking unit 507 is used to calculate the attitude control torque of the satellite at the current moment according to the inertial quaternion and inertial angular velocity of the space target, so as to drive the satellite to track the space target in real time.

[0134] In an embodiment of the present invention, the acquisition unit 501 can be used to execute step 100 in the above method embodiment, the first calculation unit 502 can be used to execute step 102 in the above method embodiment, the second calculation unit 503 can be used to execute step 104 in the above method embodiment, the third calculation unit 504 can be used to execute step 106 in the above method embodiment, the fourth calculation unit 505 can be used to execute step 108 in the above method embodiment, the fifth calculation unit 506 can be used to execute step 110 in the above method embodiment, and the tracking unit 507 can be used to execute step 112 in the above method embodiment.

[0135] In one embodiment of the present invention, the first calculation unit 502 calculates the position vector of the satellite pointing to the space target in the J2000 inertial system at the time of center intersection according to the position vectors of the satellite and the space target in the J2000 inertial system, and is used to perform the following steps:

[0136] Calculating the relative distance between the satellite and the space target at the time of center intersection according to the position vectors of the satellite and the space target in the J2000 inertial system;

[0137] Based on the position vectors of the satellite and the space target in the J2000 inertial system and the relative distance between the satellite and the space target, a unit vector of the satellite pointing to the space target at the time of center intersection is obtained;

[0138] According to the unit vector of the satellite pointing to the space target and the conversion coefficient matrix of the satellite from the J2000 inertial system to the orbital system, the position vector of the satellite pointing to the space target in the J2000 inertial system at the time of central intersection is obtained.

[0139] In one embodiment of the present invention, in the second calculation unit 503, the attitude angle includes the roll angle and pitch angle of the satellite pointing to the space target at the center intersection moment:

[0140] The attitude angle of the satellite pointing to the space target at the center intersection moment is calculated by the following formula:

[0141]

[0142] θ r =arcsin(r e (1))

[0143] In the formula, is the roll angle of the satellite pointing to the space target, θ r is the elevation angle of the satellite pointing to the space target, is the position vector of the satellite pointing to the space target.

[0144] In one embodiment of the present invention, the third calculation unit 504 is used to perform the following operations when calculating the relative velocity vector of the satellite pointing to the space target in the J2000 inertial system at the time of center intersection based on the velocity vectors of the satellite and the space target in the J2000 inertial system:

[0145] According to the velocity vectors of the satellite and the space target in the J2000 inertial system, a vertical line of sight component of the space target relative to the satellite velocity is obtained;

[0146] Based on the vertical line of sight component, satellite orbit altitude, earth radius constant and satellite orbit angular velocity, a relative velocity of the satellite and the space target being collinear is obtained;

[0147] Based on the vertical line-of-sight component of the space target relative to the satellite velocity and the relative velocity of the satellite and the space target being collinear, a relative velocity vector of the satellite pointing to the space target in the J2000 inertial system at the time of central intersection is obtained.

[0148] In one embodiment of the present invention, the fourth calculation unit 505 obtains the attitude angle and Euler axis of the satellite push-scan according to the position vector and relative velocity vector of the satellite pointing to the space target, and is used to perform the following operations:

[0149] According to the attitude angle of the satellite pointing to the space target and the relative speed of the space target and the relative speed between the satellite and the space target, the yaw angle of the satellite push-scan in the J2000 inertial system is obtained;

[0150] According to the relative distance between the satellite and the space target, the position vector and relative velocity vector of the satellite pointing to the space target, the angular velocity of the satellite push-scan in the J2000 inertial system is calculated;

[0151] Based on the satellite's attitude angle pointing to the space target, the satellite's yaw angle and the satellite's angular velocity of push-scanning in the J2000 inertial system, the satellite's attitude angular velocity of push-scanning in the J2000 inertial system and the inertial quaternion at the start of push-scanning are obtained;

[0152] Based on the attitude angular velocity of the satellite push-broom in the J2000 inertial system, the Euler axis of the satellite push-broom is obtained.

[0153] In one embodiment of the present invention, when the fifth calculation unit 506 obtains the inertial quaternion and inertial angular velocity of the space target at the current moment based on the attitude angle of the satellite pointing to the space target, the attitude angle of the satellite push-scan and the Euler axis, it is used to perform the following operations:

[0154] The angular velocity of the satellite push-scan in the J2000 inertial system is determined as the inertial quaternion of the space target at the current moment;

[0155] Based on the angular velocity of the satellite push-scan in the J2000 inertial system and the difference between the current moment and the center intersection moment, the attitude angle of the space target at the current moment is obtained;

[0156] Based on the attitude angle of the space target, the attitude angle of the satellite pointing to the space target, the Euler axis and attitude angle of the satellite push-scan, the inertial angular velocity of the space target at the current moment is obtained.

[0157] In one embodiment of the present invention, the tracking unit 507 calculates the attitude control torque of the satellite at the current moment according to the inertial quaternion and inertial angular velocity of the space target, so as to perform the following operations:

[0158] Obtaining the attitude control value of the satellite according to the inertial quaternion and the attitude measurement quaternion of the space target;

[0159] Subtracting the inertial angular velocity of the space target from the angular velocity measurement value to obtain the angular velocity control amount of the satellite;

[0160] The attitude control torque of the satellite is calculated according to the attitude control amount and the angular velocity control amount of the satellite.

[0161] It is to be understood that the structure illustrated in the embodiment of the present invention does not constitute a specific limitation on a space target tracking device using push-scan imaging of a linear array camera. In other embodiments of the present invention, a space target tracking device using push-scan imaging of a linear array camera 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.

[0162] 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.

[0163] 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 space target using push-scan imaging of a linear array camera in any embodiment of the present invention is implemented.

[0164] An embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the processor executes a method for tracking a space target using push-scan imaging of a linear array camera in any embodiment of the present invention.

[0165] 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.

[0166] 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.

[0167] 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.

[0168] 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.

[0169] 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.

[0170] 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 space target tracking method using push-scan imaging of a linear array camera provided in the above-mentioned method embodiments.

[0171] 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.

[0172] 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.

[0173] 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 space target tracking method using push-scan imaging of a linear array camera, characterized in that: include: Obtain the position vector and velocity vector of the satellite and the space target in the J2000 inertial system at the center intersection time; wherein the center intersection time is the intermediate time from the start to the end of the push-scan imaging of the space target by the satellite; According to the position vectors of the satellite and the space target in the J2000 inertial system, the position vector of the satellite pointing to the space target in the J2000 inertial system at the time of center intersection is calculated; Based on the position vector of the satellite pointing to the space target, obtaining the attitude angle of the satellite pointing to the space target at the time of center intersection; According to the velocity vectors of the satellite and the space target in the J2000 inertial system, a relative velocity vector of the satellite pointing to the space target in the J2000 inertial system at the time of center intersection is calculated; According to the position vector and relative velocity vector of the satellite pointing to the space target, the attitude angle and Euler axis of the satellite push-scan are obtained; Based on the attitude angle of the satellite pointing to the space target at the center intersection moment, the attitude angle of the satellite push-scan and the Euler axis, the inertial quaternion and the inertial angular velocity of the space target at the current moment are obtained; According to the inertial quaternion and inertial angular velocity of the space target, the attitude control torque of the satellite at the current moment is calculated to drive the satellite to track the space target in real time.

2. The method according to claim 1, characterized in that The step of calculating the position vector of the satellite pointing to the space target in the J2000 inertial system at the time of center intersection according to the position vectors of the satellite and the space target in the J2000 inertial system comprises: Calculating the relative distance between the satellite and the space target at the time of center intersection according to the position vectors of the satellite and the space target in the J2000 inertial system; Based on the position vectors of the satellite and the space target in the J2000 inertial system and the relative distance between the satellite and the space target, a unit vector of the satellite pointing to the space target at the time of center intersection is obtained; According to the unit vector of the satellite pointing to the space target and the conversion coefficient matrix of the satellite from the J2000 inertial system to the orbital system, the position vector of the satellite pointing to the space target in the J2000 inertial system at the time of central intersection is obtained.

3. The method according to claim 1, characterized in that The attitude angle includes the roll angle and pitch angle of the satellite pointing to the space target at the time of center intersection: The attitude angle of the satellite pointing to the space target at the center intersection moment is calculated by the following formula: θ r =arcsin(r e (1)) In the formula, is the roll angle of the satellite pointing to the space target, θ r is the elevation angle of the satellite pointing to the space target, is the position vector of the satellite pointing to the space target.

4. The method according to claim 1, characterized in that: The step of calculating the relative velocity vector of the satellite pointing to the space target in the J2000 inertial system at the time of center intersection according to the velocity vectors of the satellite and the space target in the J2000 inertial system comprises: According to the velocity vectors of the satellite and the space target in the J2000 inertial system, a vertical line of sight component of the space target relative to the satellite velocity is obtained; Based on the vertical line of sight component, satellite orbit altitude, earth radius constant and satellite orbit angular velocity, a relative velocity of the satellite and the space target being collinear is obtained; Based on the vertical line-of-sight component of the space target relative to the satellite velocity and the relative velocity of the satellite and the space target being collinear, a relative velocity vector of the satellite pointing to the space target in the J2000 inertial system at the time of central intersection is obtained.

5. The method according to claim 1 or 4, characterized in that: The step of obtaining the attitude angle and the Euler axis of the satellite push-scan according to the position vector and the relative velocity vector of the satellite pointing to the space target comprises: According to the attitude angle of the satellite pointing to the space target and the relative speed of the space target and the relative speed between the satellite and the space target, the yaw angle of the satellite push-scan in the J2000 inertial system is obtained; According to the relative distance between the satellite and the space target, the position vector and relative velocity vector of the satellite pointing to the space target, the angular velocity of the satellite push-scan in the J2000 inertial system is calculated; Based on the satellite's attitude angle pointing to the space target, the satellite's yaw angle and the satellite's angular velocity of push-scanning in the J2000 inertial system, the satellite's attitude angular velocity of push-scanning in the J2000 inertial system and the inertial quaternion at the start of push-scanning are obtained; Based on the attitude angular velocity of the satellite push-broom in the J2000 inertial system, the Euler axis of the satellite push-broom is obtained.

6. The method according to claim 1, characterized in that The inertial quaternion and inertial angular velocity of the space target at the current moment are obtained based on the attitude angle of the satellite pointing to the space target, the attitude angle of the satellite push-scan and the Euler axis, including: The angular velocity of the satellite push-scan in the J2000 inertial system is determined as the inertial quaternion of the space target at the current moment; Based on the angular velocity of the satellite push-scan in the J2000 inertial system and the difference between the current moment and the center intersection moment, the attitude angle of the space target at the current moment is obtained; Based on the attitude angle of the space target, the attitude angle of the satellite pointing to the space target, the Euler axis and attitude angle of the satellite push-scan, the inertial angular velocity of the space target at the current moment is obtained.

7. The method according to any one of claims 1 to 6, characterized in that The step of calculating the attitude control torque of the satellite at the current moment according to the inertial quaternion and the inertial angular velocity of the space target comprises: Obtaining the attitude control value of the satellite according to the inertial quaternion and the attitude measurement quaternion of the space target; Subtracting the inertial angular velocity of the space target from the angular velocity measurement value to obtain the angular velocity control amount of the satellite; The attitude control torque of the satellite is calculated according to the attitude control amount and the angular velocity control amount of the satellite.

8. A space target tracking device using push-scan imaging of a linear array camera, characterized in that: include: An acquisition unit, used to acquire the position vector and velocity vector of the satellite and the space target in the J2000 inertial system at the center intersection time; wherein the center intersection time is the intermediate time from the start to the end of the push-scan imaging of the space target by the satellite; A first calculation unit is used to calculate the position vector of the satellite pointing to the space target in the J2000 inertial system at the time of center intersection according to the position vectors of the satellite and the space target in the J2000 inertial system; A second calculation unit is used to obtain an attitude angle of the satellite pointing to the space target at the time of center intersection based on the position vector of the satellite pointing to the space target; A third calculation unit is used to calculate the relative velocity vector of the satellite pointing to the space target in the J2000 inertial system at the time of center intersection according to the velocity vectors of the satellite and the space target in the J2000 inertial system; A fourth calculation unit is used to obtain the attitude angle and Euler axis of the satellite push-scan according to the position vector and relative velocity vector of the satellite pointing to the space target; A fifth calculation unit is used to obtain the inertial quaternion and inertial angular velocity of the space target at the current moment based on the attitude angle of the satellite pointing to the space target at the central intersection moment, the attitude angle of the satellite push-scan and the Euler axis; The tracking unit is used to calculate the attitude control torque of the satellite at the current moment according to the inertial quaternion and inertial angular velocity of the space target, so as to drive the satellite to track the space target in real time.

9. 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 7 is implemented.

10. 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 7.

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