Fixed-point tracking and pointing control method for space target with high area-mass ratio

Abstract

The invention relates to the technical field of aerospace, in particular to a fixed-point tracking and pointing control method for a high-area-mass-ratio space target. Comprising the steps of obtaining a relative state of a space target under a satellite orbit system; calculating a satellite attitude control quantity according to the relative position and the current attitude of the satellite; calculating the relative orbit control quantity of the satellite according to the relative state of the space target and the fixed-point keeping relative position of the satellite; and according to the satellite attitude control quantity and the relative orbit control quantity, determining the on-off states of attitude control and orbit control thrusters by adopting a phase plane algorithm, and continuously determining the on-off states of the attitude control and orbit control thrusters at the current moment so as to perform fixed-point tracking and pointing control of the space target. According to the scheme provided by the invention, fixed-point tracking and pointing can be carried out on the high-area-mass-ratio space target.

Description

Technical Field

[0001] The invention relates to the field of aerospace technology, and in particular to a fixed-point tracking and aiming control method for a space target with a high surface-to-mass ratio. Background Art

[0002] The area-to-mass ratio of high-area-to-mass space targets is much greater than that of conventional spacecraft. Typical representatives include solar sails with large frontal areas, as well as very small smart dust, space targets, space chip satellites, space debris, etc. Miniaturized high-area-to-mass satellites have the advantages of low R&D costs, short design cycles, batch production, high functional density, and easy to carry. They can independently complete simple space missions or form clusters to work together. They have application prospects in environmental monitoring, deep space exploration, on-orbit patrols, high-resolution observations, and other fields.

[0003] Fixed-point tracking is a mission scenario for achieving continuous monitoring of space targets. The front and rear phases of the same orbit as the target are usually the optimal positions for completing fixed-point tracking. The orbital acceleration of high-area-to-mass ratio space targets in a low-orbit environment caused by atmospheric drag is much greater than that of traditional spacecraft. Orbital decay will cause rapid drift of relative phase, increasing the difficulty of fixed-point control. Traditional bang-bang control is effective and feasible in fixed-point tracking missions with slow relative velocity changes, but when applied to fixed-point tracking of high-area-to-mass ratio space targets, the rapid drift of relative phase will lead to frequent triggering of unilateral control, increasing the control frequency and consuming more fuel, and may even break the control boundary and cause mission failure.

[0004] Therefore, there is an urgent need to propose a fixed-point tracking method for high-surface-to-quality ratio space targets to solve the above technical problems. Summary of the invention

[0005] The embodiments of the present invention provide a method, device, electronic device and storage medium for controlling fixed-point tracking of a space target with a high area-to-quality ratio, which can perform fixed-point tracking of a space target with a high area-to-quality ratio.

[0006] In a first aspect, an embodiment of the present invention provides a method for controlling a fixed-point tracking and aiming of a space target with a high surface-to-quality ratio, comprising:

[0007] Acquire the relative state of the space target in the satellite orbit system; wherein the relative state includes the relative position and relative speed of the space target to the satellite, the satellite orbit system includes X, Y and Z axes, the +Z axis points to the center of the earth, the +X axis is located in the orbital plane and points to the flight direction, and the +Y axis is determined by the right-hand rule;

[0008] Calculating a satellite attitude control amount according to the relative position and the current attitude of the satellite; wherein the satellite attitude control amount includes a satellite attitude angle control amount and a satellite attitude angular velocity control amount;

[0009] Calculating the relative orbit control amount of the satellite according to the relative state of the space target and the relative position of the satellite fixed point; wherein the satellite orbit control amount includes the position control amount and the speed control amount of the satellite relative orbit;

[0010] According to the satellite attitude control amount and the relative orbit control amount, a phase plane algorithm is used to determine the on / off state of the attitude control and orbit control thrusters;

[0011] The current attitude control and orbit control thruster on / off status is continuously determined to perform fixed-point tracking and aiming control of the space target.

[0012] In a possible design, calculating the satellite attitude control amount according to the relative position and the current attitude of the satellite includes:

[0013] Determine the converted relative position of the space target in the satellite system according to the relative position and the attitude rotation matrix of the satellite system relative to the satellite orbit system;

[0014] Calculating the target attitude quaternion in the satellite system according to the converted relative position, the direction of the satellite target pointing axis and the attitude quaternion of the satellite system relative to the satellite orbit system;

[0015] Calculating the satellite attitude angle control amount according to the converted relative position and the direction of the satellite target pointing axis;

[0016] The satellite attitude angular velocity control amount is calculated according to the actual angular velocity of the satellite, the target attitude quaternion and the attitude quaternion motion equation function.

[0017] In a possible design, the conversion relative position is calculated by the following formula:

[0018] Rpos_btemp=C BO *Rpos_o;

[0019] Rpos_b=Rpos_btemp / |Rpos_btemp|;

[0020] Wherein, Rpos_o is the relative position, C BO is the attitude rotation matrix of the satellite orbit system, and Rpos_b is the converted relative position.

[0021] In a possible design, the target attitude quaternion is calculated by the following formula:

[0022] alpha_tp=acos(dot(PointAxis_b,Rpos_b));

[0023] e_tp = Rpos_b × PointAxis_b;

[0024] q TB =[-e_tp'*sin(0.5*alpha_tp),cos(0.5*alpha_tp)];

[0025]

[0026] Among them, PointAxis_b is the direction of the satellite target pointing axis, q BO is the attitude quaternion of the satellite system relative to the satellite orbit system, q TO is the target attitude quaternion, dot(·,·) represents vector dot product, × represents vector cross product, Represents quaternion multiplication.

[0027] In a possible design, the satellite attitude angle control amount is calculated by the following formula:

[0028] attc = alpha_tp * e_tp;

[0029] Wherein, attc is the satellite attitude angle control value;

[0030] The satellite attitude angular velocity control amount is calculated by the following formula:

[0031]

[0032] dattc=ω BO -ω TO ;

[0033] Wherein, dattc is the satellite attitude angular velocity control value, ω TO is the satellite target attitude angular velocity, ω BO is the actual attitude angular velocity of the satellite, Eq is the attitude quaternion motion equation function, and Δt is the satellite control period.

[0034] In one possible design, the position control amount of the satellite relative to the orbit is calculated by the following formula:

[0035] RelPosc=Rpos_o-RelPosT;

[0036] Wherein, RelPosT is the relative position maintained by the satellite, Rvel_o is the relative speed of the space target, and RelPosc is the position control amount;

[0037] The speed control amount of the satellite relative orbit is calculated by the following formula:

[0038] RelVelc=Rvel_o

[0039] Wherein, RelVelc is the speed control amount.

[0040] In a possible design, the use of a phase plane algorithm to determine the attitude control and orbit control thruster on / off states includes:

[0041] A first phase plane including a horizontal axis and a vertical axis is established, wherein the first phase plane is defined by a first expression The first symmetry formula symmetrical about the origin divides the coordinate system into three regions. The region where both the horizontal axis and the vertical axis are positive is the first phase plane region 1, the region where both the horizontal axis and the vertical axis are negative is the first phase plane region 2, and the remaining region is the first phase plane region 3;

[0042] A second phase plane including a horizontal axis and a vertical axis is established, and the second phase plane is defined by the first expression And the second expression The formed broken line divides the coordinate system into two areas, the right side of the horizontal axis of the second phase plane is the positive direction, the upper side of the vertical axis of the second phase plane is the positive direction, the part located on the upper side of the second expression and the right side of the first expression is the second phase plane area 1, and the part located on the left side of the first expression and the lower side of the second expression is the second phase plane area 2;

[0043] For each axis of the three-axis attitude control thruster, based on the first phase plane, the following operations are performed:

[0044] The attitude angle control amount in the direction of the axis is set as the horizontal coordinate, and the attitude angular velocity control amount in the direction of the axis is set as the vertical coordinate. The phase plane variable θ in the first expression is c , are respectively taken as the attitude angular velocity and the attitude angular velocity control amount, K J and θ D is an empirical value, the satellite target attitude angular velocity and the satellite attitude angular velocity control amount in the direction of the axis calculated are substituted into the first phase plane, and the area they fall into is observed. When they fall into area 1 of the first phase plane, the attitude control thruster in the negative direction of the axis is turned on; when they fall into area 2 of the first phase plane, the attitude control thruster in the positive direction of the axis is turned on; when they fall into area 3 of the first phase plane, both the attitude control thrusters in the positive and negative directions of the axis are turned off;

[0045] In the y-axis and z-axis directions of the orbit control thruster, based on the first phase plane, the following operations are performed:

[0046] The position control amount in the direction of the axis is set as the horizontal coordinate, and the speed control amount in the direction of the axis is set as the horizontal coordinate. The phase plane variable θ in the first expression c , are taken as relative position control quantity and relative speed control quantity respectively, K J and θ D is an empirical value, the calculated position control amount in the direction of the axis is substituted into the first phase plane, and the area it falls into is observed. When it falls into area 1 of the first phase plane, the orbit control thruster in the positive direction of the axis is turned on; when it falls into area 2 of the first phase plane, the orbit control thruster in the negative direction of the axis is turned on; when it falls into area 3 of the first phase plane, both the orbit control thrusters in the positive and negative directions of the axis are turned off;

[0047] In the x-axis direction of the orbit control thruster, based on the second phase plane, the following operations are performed:

[0048] The position control amount in the direction of the axis is set as the horizontal coordinate, and the speed control amount in the direction of the axis is set as the horizontal coordinate. The phase plane variable θ in the first expression c , are taken as relative position control quantity and relative speed control quantity respectively, K J and θ D is an empirical value, and the calculated position control amount in the direction of the axis is substituted into the second phase plane to observe the area where it falls. When it falls into area 1 of the second phase plane, the orbit control thrusters in the positive and negative directions of the axis are turned off; when it falls into area 2 of the second phase plane, the orbit control thrusters in the negative direction of the axis are turned on.

[0049] In a second aspect, an embodiment of the present invention further provides a fixed-point tracking and aiming control device for a high surface-to-quality ratio space target, which is used to implement any of the above methods, and the device includes:

[0050] The first unit is used to obtain the relative state of the space target in the satellite orbit system; wherein the relative state includes the relative position and relative speed of the space target to the satellite, and the satellite orbit system includes X, Y and Z axes, the +Z axis points to the center of the earth, the +X axis is located in the orbital plane and points to the flight direction, and the +Y axis is determined by the right-hand rule;

[0051] The second unit is used to calculate the satellite attitude control amount according to the relative position and the current attitude of the satellite; wherein the satellite attitude control amount includes the satellite attitude angle control amount and the satellite attitude angular velocity control amount;

[0052] A third unit is used to calculate the relative orbit control amount of the satellite according to the relative state of the space target and the satellite fixed point maintenance relative position; wherein the satellite orbit control amount includes the position control amount and the speed control amount of the satellite relative orbit;

[0053] The fourth unit is used to determine the on / off state of the attitude control and orbit control thrusters by using a phase plane algorithm according to the satellite attitude control amount and the relative orbit control amount;

[0054] The fifth unit is used to continuously determine the current attitude control and orbit control thruster on / off states to perform fixed-point tracking and aiming control of the space target. In a third aspect, an embodiment of the present invention further provides an electronic device, including a memory and a processor, wherein a computer program is stored in the memory, and when the processor executes the computer program, the method described in any embodiment of this specification is implemented.

[0055] 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.

[0056] Compared with the prior art, the present invention has at least the following beneficial effects:

[0057] 1) Decompose the fixed-point tracking and aiming control into attitude control for target pointing and relative orbit control for fixed-point holding, which are completed by attitude control thrusters and orbit control thrusters respectively to achieve decoupled control;

[0058] 2) The phase plane algorithm is used to directly determine the on / off state of the attitude and orbit control thrusters, and the control strategy is simple and effective;

[0059] 3) A unilateral limit cycle control strategy is used in the x-axis direction of the orbital system to offset the drift of the relative phase through relative velocity overshoot, effectively reducing the control frequency and saving fuel. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] 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.

[0061] Figure 1 This is a flow chart of a method for controlling a fixed-point tracking and aiming of a space target with a high surface-to-quality ratio provided by an embodiment of the present invention;

[0062] Figure 2 is the first phase plane control switching curve;

[0063] Figure 3 is the second phase plane control switching curve;

[0064] Figure 4 is the relative position control result;

[0065] Figure 5 It is the target pointing attitude control result;

[0066] Figure 6is a hardware architecture diagram of an electronic device provided by an embodiment of the present invention;

[0067] Figure 7 The present invention is a structural diagram of a fixed-point tracking and aiming control device for a space target with a high surface-to-quality ratio provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0068] 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.

[0069] The specific implementation of the above concept is described below.

[0070] Please refer to Figure 1 The embodiment of the present invention provides a method for controlling a fixed-point tracking and aiming of a space target with a high surface-to-quality ratio, which is characterized by comprising:

[0071] Obtain the relative state of the space target in the satellite orbit system; the relative state includes the relative position and relative speed of the space target to the satellite. The satellite orbit system includes X, Y and Z axes, the +Z axis points to the center of the earth, the +X axis is located in the orbital plane and points to the flight direction, and the +Y axis is determined by the right-hand rule;

[0072] Calculate the satellite attitude control amount according to the relative position and the current attitude of the satellite; wherein the satellite attitude control amount includes the satellite attitude angle control amount and the satellite attitude angular velocity control amount;

[0073] According to the relative state of the space target and the relative position of the satellite fixed point, the relative orbit control amount of the satellite is calculated; wherein the satellite orbit control amount includes the position control amount and the speed control amount of the satellite relative orbit;

[0074] According to the satellite attitude control quantity and relative orbit control quantity, the phase plane algorithm is used to determine the on / off status of the attitude control and orbit control thrusters;

[0075] Constantly determine the current state of attitude control and orbit control thrusters to perform point tracking and aiming control of space targets.

[0076] In this embodiment, the relative state of the space target can be obtained by measuring the relative sensor on the satellite. After calculating the satellite attitude control amount and the relative orbit control amount, the data in each axis direction on the attitude control axis and the orbit control axis are extracted respectively, and the data in each axis direction are put into the phase plane, and the opening and closing of the thruster of the axis is judged according to the landing point of the data in the phase plane. The data at the current moment is continuously calculated, that is, the satellite attitude control amount and the relative orbit control amount under different attitude control axes and orbit control axes, and the opening and closing of the thruster are continuously judged according to the data at the current moment, and finally fixed-point tracking and aiming are realized.

[0077] In some embodiments of the present invention, calculating the satellite attitude control amount according to the relative position and the current attitude of the satellite includes:

[0078] According to the relative position and the attitude rotation matrix of the satellite system relative to the satellite orbit system, the relative position of the space target in the satellite system is determined;

[0079] Calculate the target attitude quaternion in the satellite system according to the converted relative position, the direction of the satellite target pointing axis and the attitude quaternion of the satellite system relative to the satellite orbit system;

[0080] Calculate the satellite attitude angle control value according to the converted relative position and the direction of the satellite target pointing axis;

[0081] The satellite attitude angular velocity control quantity is calculated based on the actual satellite angular velocity, the target attitude quaternion and the attitude quaternion motion equation function.

[0082] In some embodiments of the present invention, the conversion relative position is calculated by the following formula:

[0083] Rpos_btemp=C BO *Rpos_o;

[0084] Rpos_b=Rpos_btemp / |Rpos_btemp|;

[0085] Among them, Rpos_o is the relative position, C BO is the attitude rotation matrix of the satellite orbit system, and Rpos_b is the relative position of the conversion.

[0086] In some embodiments of the present invention, the target posture quaternion is calculated by the following formula:

[0087] alpha_tp=acos(dot(PointAxis_b,Rpos_b));

[0088] e_tp = Rpos_b × PointAxis_b;

[0089] q TB=[-e_tp'*sin(0.5*alpha_tp),cos(0.5*alpha_tp)];

[0090]

[0091] Among them, PointAxis_b is the direction of the satellite target pointing axis, q BO is the attitude quaternion of the satellite system relative to the satellite orbit system, q TO is the target attitude quaternion, dot(·,·) represents vector dot product, × represents vector cross product, Represents quaternion multiplication.

[0092] In some embodiments of the present invention, the satellite attitude angle control amount is calculated by the following formula:

[0093] attc = alpha_tp * e_tp;

[0094] Among them, attc is the satellite attitude angle control value;

[0095] The satellite attitude angular velocity control value is calculated by the following formula:

[0096]

[0097] dattc=ω BO -ω TO ;

[0098] Among them, dattc is the satellite attitude angular velocity control value, ω TO is the satellite target attitude angular velocity, ω BO is the actual attitude angular velocity of the satellite, Eq is the attitude quaternion motion equation function, and Δt is the satellite control period.

[0099] In this embodiment, ω can be determined based on a4. TO Is it a negative number? When a4 is less than 0, ω TO =-ω TO .

[0100] In this embodiment, a 4 =q′ TO (1) q TO (1)+q′ TO (2) q TO (2)+q′ TO (3) q TO (3)+q′ TO (4) q TO (4).

[0101] In this embodiment, the attitude quaternion motion equation function is:

[0102] In some embodiments of the present invention, the position control amount of the satellite relative to the orbit is calculated by the following formula:

[0103] RelPosc=Rpos_o-RelPosT;

[0104] Among them, RelPosT is the relative position of the satellite, Rvel_o is the relative speed of the space target, and RelPosc is the position control value;

[0105] The speed control amount of the satellite relative to the orbit is calculated by the following formula:

[0106] RelVelc=Rvel_o

[0107] Among them, RelVelc is the speed control quantity.

[0108] In some embodiments of the present invention, a phase plane algorithm is used to determine the on / off state of attitude control and orbit control thrusters, including:

[0109] Establish the first phase plane including the horizontal axis and the vertical axis. The first phase plane is obtained by the first expression The first symmetry formula symmetrical about the origin divides the coordinate system into three regions. The region where both the horizontal axis and the vertical axis are positive is the first phase plane region 1, the region where both the horizontal axis and the vertical axis are negative is the first phase plane region 2, and the remaining region is the first phase plane region 3;

[0110] Establish a second phase plane including the horizontal axis and the vertical axis. The second phase plane is expressed by the first expression And the second expression The formed broken line divides the coordinate system into two areas, the right side of the horizontal axis of the second phase plane is the positive direction, the upper side of the vertical axis of the second phase plane is the positive direction, the part located on the upper side of the second expression and the right side of the first expression is the second phase plane area 1, and the part located on the left side of the first expression and the lower side of the second expression is the second phase plane area 2;

[0111] For each axis of the three-axis attitude control thruster, based on the first phase plane, the following operations are performed:

[0112] The attitude angle control amount in the direction of the axis is set as the horizontal coordinate, and the attitude angular velocity control amount in the direction of the axis is set as the vertical coordinate. The phase plane variable θ in the first expression is c , are respectively taken as the attitude angular velocity and the attitude angular velocity control amount, K J and θ Dis an empirical value. The calculated satellite target attitude angular velocity and satellite attitude angular velocity control amount in the direction of the axis are substituted into the first phase plane, and the area they fall into is observed. When it falls into area 1 of the first phase plane, the attitude control thruster in the negative direction of the axis is turned on; when it falls into area 2 of the first phase plane, the attitude control thruster in the positive direction of the axis is turned on; when it falls into area 3 of the first phase plane, both the attitude control thrusters in the positive and negative directions of the axis are turned off.

[0113] The Y-axis and Z-axis directions of the orbital control thruster are based on the first phase plane and are executed:

[0114] The position control amount in the direction of the axis is set as the horizontal coordinate, and the speed control amount in the direction of the axis is set as the horizontal coordinate. The phase plane variable θ in the first expression c , are taken as relative position control quantity and relative speed control quantity respectively, K J and θ D is an empirical value. The calculated position control amount in the direction of the axis is substituted into the first phase plane to observe the area it falls into. When it falls into area 1 of the first phase plane, the orbit control thruster in the positive direction of the axis is turned on; when it falls into area 2 of the first phase plane, the orbit control thruster in the negative direction of the axis is turned on; when it falls into area 3 of the first phase plane, both the orbit control thrusters in the positive and negative directions of the axis are turned off.

[0115] In the x-axis direction of the orbit control thruster, based on the second phase plane, the following operations are performed:

[0116] The position control amount in the direction of the axis is set as the horizontal coordinate, and the speed control amount in the direction of the axis is set as the horizontal coordinate. The phase plane variable θ in the first expression c , are taken as relative position control quantity and relative speed control quantity respectively, K J and θ D It is an empirical value. The calculated position control amount in the direction of the axis is substituted into the second phase plane, and the area it falls into is observed. When it falls into area 1 of the second phase plane, the orbit control thrusters in the positive and negative directions of the axis are turned off. When it falls into area 2 of the second phase plane, the orbit control thrusters in the negative direction of the axis are turned on. Specific embodiments

[0118] The present invention is described in detail below with reference to specific examples.

[0119] The working conditions are as follows:

[0120] High surface-to-mass ratio space target (target) drag area 3m 2 , mass 6kg; tracking satellite drag area 1m 2 , mass 200kg, the initial orbital data of the two are:

[0121] Instantaneous root number a(km) e i(degree) Ω(degrees) ω(degrees) M(degrees) Target 6721 0.00124 53 115.068 0 145.1035 Follow the satellite 6721 0.00124 53 115.068 0 145.095

[0122] The target pointing axis of the tracking satellite is PointAxis_b = [1,0,0]', and the target relative position is RelPosT = [1000,0,0]m. The measurement error and delay of the relative sensor are not considered.

[0123] Follow the steps below to complete the satellite’s aiming and tracking of the target:

[0124] (1) According to the measurement of the on-board relative sensor, the relative state of the target in the satellite orbit system is obtained, the relative position Rpos_o = [996.066, -0.000232, -0.632]'m, the relative velocity Rvel_o = [-0.000861, -0.000918, 0.00116]'m / s.

[0125] (2) Based on the relative position and the current attitude of the satellite, the target attitude of the satellite’s target pointing axis and the satellite attitude control value are calculated.

[0126] Assume that the current satellite attitude rotation matrix C relative to the orbital coordinate system BO 、Attitude quaternion q BO 、Attitude angular velocity ω BO They are

[0127] q BO =[0 0 0 1],ω BO =[0 0 0].

[0128] The relative position of the target in the satellite system Rpos_btemp = C BO *Rpos_o=[996.066,-0.000232,-0.632]'m, calculate the target attitude quaternion qTO by the following formula: Rpos_b=Rpos_btemp / |Rpos_btemp|=[0.999999799,-2.33e-7,-6.345e-4]';

[0129] alpha_tp=acos(dot(PointAxis_b,Rpos_b))=0.0006345';

[0130] e_tp=Rpos_b×PointAxis_b=[0,-0.0006345,2.329e-7];

[0131] qTB=[-e_tp'*sin(0.5*alpha_tp),cos(0.5*alpha_tp)]=[0,2.013e-7,-7.389e-11, 0.999999949676843];

[0133]

[0134] This is the first calculation, and the satellite target attitude angular velocity ω is set TO =[0,0,0], then the target attitude of the satellite target pointing axis and the satellite attitude control amount are calculated as

[0135] attc=alpha_tp*e_tp=[0,-4.0258e-07,1.478e-10];

[0136] dattc=ω BO -ω TO =[0,0,0].

[0137] (3) Based on the relative state of the space target in the satellite orbit system and the relative position maintained by the satellite, the satellite relative orbit control quantity is calculated.

[0138] RelPosc=Rpos_o-RelPosT=[-3.934,-0.000232,-0.632]'m

[0139] RelVelc=Rvel_o=[-0.000861,-0.000918,0.00116]'m / s

[0140] (4) Based on the satellite attitude control quantity and relative orbit control quantity, the phase plane algorithm is used to determine the on / off status of the attitude and orbit control thrusters.

[0141] The three-axis attitude control uses the first phase plane control switch curve, the phase plane variable θ c , The angle control value and angular velocity control value are taken as degrees and degrees / s respectively, and the expression of the AB segment switch curve is taken as The current three-axis attitude control values ​​are all in range ③, so the attitude control thrusters are all shut down.

[0142] The relative track control in the y and z axis directions adopts the first phase plane control switch curve, and the phase plane variable θ c , They are taken as the relative position control quantity and relative speed control quantity (the units are m and m / s respectively), and the expression of the AB segment switch curve is taken as Currently, the relative orbit control quantities in the y and z directions are both in interval ③, so the orbit control thrusters in the y and z directions are both turned off.

[0143] The relative track control in the x-axis direction adopts the second phase plane control switch curve, and the phase plane variable θ c , are taken as the relative position control quantity and relative speed control quantity (units are m and m / s respectively), and the AC section switch curve expression is taken as The expression of the CD segment switching curve is taken as The current relative orbit control value in the x direction is in interval ①, so all orbit control thrusters in the x direction are turned off.

[0144] (5) Repeat steps (1) to (4) to calculate the attitude and orbit control variables based on the relative measurements, and determine the switches of the corresponding thrusters based on the phase plane partitions. Figure 4 is the control result of relative position, Figure 5 is the result of attitude control.

[0145] like Figure 6 , Figure 7 As shown, the embodiment of the present invention provides a fixed-point tracking and aiming control device for a space target with a high surface-to-mass ratio. The device embodiment can be implemented by software, or by hardware or a combination of software and hardware. From the hardware level, Figure 6 As shown, it is a hardware architecture diagram of an electronic device in which a fixed-point tracking and aiming control device for a space target with a high surface-to-quality ratio is provided in an embodiment of the present invention. Figure 6 In addition to the processor, memory, network interface, and non-volatile memory shown, the electronic device in the embodiment may also include other hardware, such as a forwarding chip responsible for processing messages, etc. Taking software implementation as an example, Figure 7 As shown, as a device in a logical sense, the CPU of the electronic device in which it is located reads the corresponding computer program in the non-volatile memory into the internal memory and runs it. This embodiment provides a fixed-point tracking and aiming control device for a high surface quality ratio space target, including:

[0146] The first unit is used to obtain the relative state of the space target in the satellite orbit system; wherein the relative state includes the relative position and relative speed of the space target to the satellite, and the satellite orbit system includes X, Y and Z axes, the +Z axis points to the center of the earth, the +X axis is located in the orbital plane and points to the flight direction, and the +Y axis is determined by the right-hand rule;

[0147] The second unit is used to calculate the satellite attitude control amount according to the relative position and the current attitude of the satellite; wherein the satellite attitude control amount includes the satellite attitude angle control amount and the satellite attitude angular velocity control amount;

[0148] A third unit is used to calculate the relative orbit control amount of the satellite according to the relative state of the space target and the satellite fixed point maintenance relative position; wherein the satellite orbit control amount includes the position control amount and the speed control amount of the satellite relative orbit;

[0149] The fourth unit is used to determine the on / off state of the attitude control and orbit control thrusters by using a phase plane algorithm according to the satellite attitude control amount and the relative orbit control amount;

[0150] The fifth unit is used to continuously determine the current attitude control and orbit control thruster on / off states to perform fixed-point tracking and aiming control of the space target.

[0151] It is to be understood that the structure illustrated in the embodiment of the present invention does not constitute a specific limitation on a fixed-point tracking and aiming control device for a space target with a high area-to-mass ratio. In other embodiments of the present invention, a fixed-point tracking and aiming control device for a space target with a high area-to-mass ratio 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.

[0152] 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.

[0153] An embodiment of the present invention further provides an electronic device, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, a fixed-point tracking and aiming control method for a high-area-to-quality ratio space target in any embodiment of the present invention is implemented.

[0154] 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 fixed-point tracking and aiming control method for a high-area-to-quality ratio space target in any embodiment of the present invention.

[0155] 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.

[0156] 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.

[0157] 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.

[0158] 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.

[0159] 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.

[0160] 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. In the absence of further restrictions, the elements defined by the statement "comprise a ..." do not exclude the presence of other identical factors in the process, method, article or device including the elements.

[0161] 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.

[0162] 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 and aiming a high-surface-to-mass ratio space target, characterized in that: include: Acquire the relative state of the space target in the satellite orbit system; wherein the relative state includes the relative position and relative speed of the space target to the satellite, the satellite orbit system includes X, Y and Z axes, the +Z axis points to the center of the earth, the +X axis is located in the orbital plane and points to the flight direction, and the +Y axis is determined by the right-hand rule; Calculating a satellite attitude control amount according to the relative position and the current attitude of the satellite; wherein the satellite attitude control amount includes a satellite attitude angle control amount and a satellite attitude angular velocity control amount; Calculating the relative orbit control amount of the satellite according to the relative state of the space target and the relative position of the satellite fixed point; wherein the satellite orbit control amount includes the position control amount and the speed control amount of the satellite relative orbit; According to the satellite attitude control amount and the relative orbit control amount, a phase plane algorithm is used to determine the on / off state of the attitude control and orbit control thrusters; The current attitude control and orbit control thruster on / off status is continuously determined to perform fixed-point tracking and aiming control of the space target.

2. The fixed-point tracking and aiming control method according to claim 1, characterized in that: Calculating the satellite attitude control amount according to the relative position and the current attitude of the satellite includes: Determine the converted relative position of the space target in the satellite system according to the relative position and the attitude rotation matrix of the satellite system relative to the satellite orbit system; Calculating the target attitude quaternion in the satellite system according to the converted relative position, the direction of the satellite target pointing axis and the attitude quaternion of the satellite system relative to the satellite orbit system; Calculating the satellite attitude angle control amount according to the converted relative position and the direction of the satellite target pointing axis; The satellite attitude angular velocity control amount is calculated according to the actual angular velocity of the satellite, the target attitude quaternion and the attitude quaternion motion equation function.

3. The fixed-point tracking and aiming control method according to claim 2, characterized in that: The conversion relative position is calculated by the following formula: Rpos_btemp=C BO *Rpos_o; Rpos_b=Rpos_btemp / |Rpos_btemp|; Wherein, Rpos_o is the relative position, C BO is the attitude rotation matrix of the satellite orbit system, and Rpos_b is the converted relative position.

4. The fixed-point tracking and aiming control method according to claim 3, characterized in that: The target attitude quaternion is calculated by the following formula: alpha_tp=acos(dot(PointAxis_b,Rpos_b)); e_tp = Rpos_b × PointAxis_b; q TB =[-e_tp'*sin(0.5*alpha_tp),cos(0.5*alpha_tp)]; Among them, PointAxis_b is the direction of the satellite target pointing axis, q BO is the attitude quaternion of the satellite system relative to the satellite orbit system, q TO is the target attitude quaternion, dot(·,·) represents vector dot product, × represents vector cross product, Represents quaternion multiplication.

5. The fixed-point tracking and aiming control method according to claim 4, characterized in that: The satellite attitude angle control value is calculated by the following formula: attc = alpha_tp * e_tp; Wherein, attc is the satellite attitude angle control value; The satellite attitude angular velocity control amount is calculated by the following formula: dattc=ω BO -oh TO ; Wherein, dattc is the satellite attitude angular velocity control value, ω TO is the satellite target attitude angular velocity, ω BO is the actual attitude angular velocity of the satellite, Eq is the attitude quaternion motion equation function, and Δt is the satellite control period.

6. The fixed-point tracking control method according to claim 1, characterized in that: The position control amount of the satellite relative orbit is calculated by the following formula: RelPosc=Rpos_o-RelPosT; Wherein, RelPosT is the relative position maintained by the satellite, Rvel_o is the relative speed of the space target, and RelPosc is the position control amount; The speed control amount of the satellite relative orbit is calculated by the following formula: RelVelc=Rvel_o Wherein, RelVelc is the speed control amount.

7. The fixed-point tracking and aiming control method according to claim 1, characterized in that: The method of using a phase plane algorithm to determine the on / off state of the attitude control and orbit control thrusters includes: A first phase plane including a horizontal axis and a vertical axis is established, wherein the first phase plane is defined by a first expression The first symmetry formula symmetrical about the origin divides the coordinate system into three regions. The region where both the horizontal axis and the vertical axis are positive is the first phase plane region 1, the region where both the horizontal axis and the vertical axis are negative is the first phase plane region 2, and the remaining region is the first phase plane region 3; A second phase plane including a horizontal axis and a vertical axis is established, and the second phase plane is defined by the first expression And the second expression The formed broken line divides the coordinate system into two areas, the right side of the horizontal axis of the second phase plane is the positive direction, the upper side of the vertical axis of the second phase plane is the positive direction, the part located on the upper side of the second expression and the right side of the first expression is the second phase plane area 1, and the part located on the left side of the first expression and the lower side of the second expression is the second phase plane area 2; For each axis of the three-axis attitude control thruster, based on the first phase plane, the following operations are performed: The attitude angle control amount in the direction of the axis is set as the horizontal coordinate, and the attitude angular velocity control amount in the direction of the axis is set as the vertical coordinate. The phase plane variable θ in the first expression is c , are respectively taken as the attitude angular velocity and the attitude angular velocity control amount, K J and θ D is an empirical value, the satellite target attitude angular velocity and the satellite attitude angular velocity control amount in the direction of the axis calculated are substituted into the first phase plane, and the area they fall into is observed. When they fall into area 1 of the first phase plane, the attitude control thruster in the negative direction of the axis is turned on; when they fall into area 2 of the first phase plane, the attitude control thruster in the positive direction of the axis is turned on; when they fall into area 3 of the first phase plane, both the attitude control thrusters in the positive and negative directions of the axis are turned off; The Y-axis and Z-axis directions of the orbit control thruster are based on the first phase plane and are executed: The position control amount in the direction of the axis is set as the horizontal coordinate, and the speed control amount in the direction of the axis is set as the horizontal coordinate. The phase plane variable θ in the first expression c , are taken as relative position control quantity and relative speed control quantity respectively, K J and θ D is an empirical value, the calculated position control amount in the direction of the axis is substituted into the first phase plane, and the area it falls into is observed. When it falls into area 1 of the first phase plane, the orbit control thruster in the positive direction of the axis is turned on; when it falls into area 2 of the first phase plane, the orbit control thruster in the negative direction of the axis is turned on; when it falls into area 3 of the first phase plane, both the orbit control thrusters in the positive and negative directions of the axis are turned off; In the x-axis direction of the orbit control thruster, based on the second phase plane, the following operations are performed: The position control amount in the direction of the axis is set as the horizontal coordinate, and the speed control amount in the direction of the axis is set as the horizontal coordinate. The phase plane variable θ in the first expression c , are taken as relative position control quantity and relative speed control quantity respectively, K J and θ D is an empirical value, and the calculated position control amount in the direction of the axis is substituted into the second phase plane to observe the area where it falls. When it falls into area 1 of the second phase plane, the orbit control thrusters in the positive and negative directions of the axis are turned off; when it falls into area 2 of the second phase plane, the orbit control thrusters in the negative direction of the axis are turned on.

8. A fixed-point tracking and aiming control device for a high surface-to-mass ratio space target, characterized in that: For implementing the method according to any one of claims 1 to 7, the device comprises: The first unit is used to obtain the relative state of the space target in the satellite orbit system; wherein the relative state includes the relative position and relative speed of the space target to the satellite, and the satellite orbit system includes X, Y and Z axes, the +Z axis points to the center of the earth, the +X axis is located in the orbital plane and points to the flight direction, and the +Y axis is determined by the right-hand rule; The second unit is used to calculate the satellite attitude control amount according to the relative position and the current attitude of the satellite; wherein the satellite attitude control amount includes the satellite attitude angle control amount and the satellite attitude angular velocity control amount; A third unit is used to calculate the relative orbit control amount of the satellite according to the relative state of the space target and the relative position of the satellite fixed point; wherein the satellite orbit control amount includes the position control amount and the speed control amount of the satellite relative orbit; The fourth unit is used to determine the on / off state of the attitude control and orbit control thrusters by using a phase plane algorithm according to the satellite attitude control amount and the relative orbit control amount; The fifth unit is used to continuously determine the current attitude control and orbit control thruster on / off states to perform fixed-point tracking and aiming control of the space target.

9. An electronic 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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