On-line high-precision alignment and keeping method for double solar wing sailboards of spacecraft

Abstract

The invention provides an online high-precision alignment and keeping method for double solar wing sailboards of a spacecraft, which can be applied to an ultra-low orbit spacecraft with double solar wing sailboards. The turning angle error of the two wing sailboards is calculated by obtaining the return turning angle of the two wing sailboards, one wing sailboard serves as the standard, the other wing sailboard automatically adjusts the driving speed according to the turning angle error of the two wing sailboards, the other wing sailboard is aligned to the standard sailboard, and the turning angle error of the two wing sailboards is reduced. The method can be used for closed-loop control of the sailboard, aerodynamic interference caused by rotation angle errors of the sailboards on the two wings of the ultra-low orbit spacecraft is greatly reduced, and the attitude stability of the spacecraft can be effectively improved.

Description

Technical Field

[0001] The present invention provides a method for online high-precision alignment and holding of dual solar wing sail panels of a spacecraft, which can be applied to an ultra-low-orbit spacecraft with dual solar wing sail panels and belongs to the field of satellite control. Background Art

[0002] In order to obtain more diverse earth remote sensing data, the traditional spacecraft payload that passively receives surface signals can no longer meet the use requirements, and a spacecraft payload that actively sends detection signals to the ground has come into being. However, due to factors such as transmission power, some spacecraft must work in ultra-low orbits. In order to minimize the aerodynamic interference caused by atmospheric resistance, such spacecraft are often configured with a symmetrical configuration of dual solar wing sails. Spacecraft with symmetrical configuration of dual solar wing sails can reduce the aerodynamic interference caused by atmospheric resistance, but when the dual solar wings track the sun, due to the asynchronous rotation angles of the two wings, the interference torque will suddenly reverse in some special positions, causing the spacecraft attitude to fluctuate. The existing technical means realize closed-loop control by capturing the sun when the solar wing sail reaches the zero position, ignoring the asymmetric problem of aerodynamic interference caused by the rotation angle errors of the two wings. At present, there is no effective method for online high-precision alignment and maintenance of dual solar wing sails in engineering; therefore, it is necessary to invent a method that can autonomously align and maintain high-precision according to the two wing sails to improve the accuracy of spacecraft attitude control. Summary of the invention

[0003] The technical problem solved by the present invention is: the present invention provides a method for online high-precision alignment and maintenance of dual solar wing sailboards of a spacecraft. Under the premise of ensuring that the solar wing sailboard on the sun-facing side tracks the sun normally, the solar wing sailboard on the back side is adjusted to make the rotation angles of the two wing sailboards consistent, thereby achieving aerodynamic interference symmetry, which can effectively improve the attitude control accuracy of the ultra-low orbit spacecraft.

[0004] The technical solution of the present invention is: in the first aspect, a method for online high-precision alignment and maintenance of dual solar wing sail panels of a spacecraft is provided, comprising:

[0005] S1, according to the return angle PY_Sada_Agl of the sailboard on the back side and the return angle NY_Sada_Agl of the sailboard on the sun-facing wing, and combined with the zero-position installation deviation Delt_PNY of the sailboard on the solar wing, calculate the difference between the angles of the sailboards on the two wings Delt_Sada_Agl;

[0006] S2, according to the calculated difference between the turning angles of the two wing sailboards Delt_Sada_Agl, determine the position of the sailboard on the back side relative to the sailboard on the sun side, and then determine the driving speed adjustment direction Addir of the sailboard on the back side;

[0007] S3, taking the driving speed NY_fbctrl of the sailboard on the sun-facing side as a reference, the driving speed PY_fbctrl of the sailboard on the back-facing side is adjusted by one gear;

[0008] S4, determining the adjustment time AdjustT of the driving control command of the sailboard on the back side according to the difference between the rotation angles of the two sailboards Delt_Sada_Agl obtained by the above calculation;

[0009] S5, within the adjustment time AdjustT, adjust the two wing sailboards according to the driving speed of the sun-facing sailboard and the driving speed of the sun-facing sailboard set in S3; after the adjustment time AdjustT ends, calculate the difference between the rotation angles of the two wing sailboards again. If the minimum accuracy requirement is met, the return rotation angles of the two wing sailboards are consistent, and the two wing sailboards are aligned; if the minimum accuracy requirement is not met, return to S1 for recalculation;

[0010] S6. After alignment, the driving speed of the back sun-facing sailboard is kept consistent with the driving speed of the sun-facing solar wing sailboard, so as to maintain the alignment of the two wing sailboards.

[0011] Preferably, the return angle refers to the angle between the solar wing sailboard and the mounting surface, which is obtained by integrating the driving speed of the driving control module in the solar wing sailboard;

[0012] The return angle of the solar wing sailboard changes with the sailboard drive control, and its range is 0 to 360°;

[0013] Zero position refers to an initial position of the solar wing sailboard, including horizontal zero position and vertical zero position, which is determined by the zero position sensor;

[0014] Zero installation deviation refers to the deviation of the zero sensor relative to the theoretical design position during installation, which is affected by processing accuracy and assembly error;

[0015] The driving speed of the sailboard refers to the rotation speed of the solar wing sailboard. Since the solar wing sailboard driver is a stepping type, MinV is its step length;

[0016] The driving speed of the sailboard changes in steps upward and downward with the orbital angular velocity as the center. One step is called a gear, which is the minimum accuracy requirement of the difference between the turning angles of the two wings of the sailboard.

[0017] Alignment is the state where the corners of the two wing panels are the same.

[0018] Preferably, NY_fbctrl and PY_fbctrl are at an orbital angular velocity ω0 when tracking the sun normally. For low-Earth orbit satellites, the orbital angular velocity ω0 is between 0.06° / s and 0.07° / s, and the corresponding minimum accuracy requirement is between 0.0002° and 0.0004°.

[0019] Preferably, the calculation method of the solar wing sailboard zero position installation deviation Delt_PNY is:

[0020] Delt_PNY=(Pylw_Offset-Kstate*Pylw_Widh*0.5)-(Nylw_Offset-Kstate*Nylw_Widh*0.5)

[0021] Wherein, Pylw_Offset and Nylw_Offset are the zero-position installation deviations of the solar wing sailboards on the back side and the sun side, respectively, which are constant values ​​and are measured after the solar wing sailboards are installed; Pylw_Widh and Nylw_Widh are the zero-position widths of the solar wing sailboards on the back side and the sun side, respectively, which are constant values ​​and are measured after the solar wing sailboards are installed; Kstate represents the flight direction of the spacecraft, when the spacecraft is flying forward, Kstate=1, when the spacecraft is flying backward, Kstate=-1;

[0022] The zero position width refers to the angular range near the zero position when the solar wing sail panel rotates. This range depends on the accuracy of the zero position sensor. The returned rotation angle within this range is the zero position value.

[0023] Preferably, the calculation method of the difference between the turning angles of the solar wing sailboards on the back side and the sun side, Delt_Sada_Agl, is:

[0024] Delt_Sada_Agl=PY_Sada_Agl-NY_Sada_Agl+Delt_PNY.

[0025] Preferably, the calculation method of the driving speed adjustment direction Addir of the sailboard on the back side is:

[0026] When Delt_Sada_Agl>MinV, the sailboard on the back side needs to slow down, so Addir=-1;

[0027] When Delt_Sada_Agl<-MinV, the sailboard on the back side needs to be accelerated, so Addir=1;

[0028] When |Delt_Sada_Agl|<MinV, Addir=0;

[0029] MinV is the step length of the step-type solar wing sailboard drive, that is, the gear position.

[0030] Preferably, the calculation method of the driving speed PY_fbctrl of the sailboard on the back side is:

[0031] PY_fbctrl=NY_fbctrl+Addir*MinV.

[0032] Preferably, the calculation method of the adjustment time AdjustT is:

[0033] AdjustT=Delt_Sada_Agl / MinV

[0034] MinV is the step length of the step-type solar wing sailboard drive, that is, the gear position.

[0035] In a second aspect, a terminal device is provided, characterized in that it includes:

[0036] a memory for storing instructions executed by at least one processor;

[0037] The processor is used to execute instructions stored in the memory to implement the online high-precision alignment and maintenance method of the dual solar wing panels of the spacecraft as described above.

[0038] According to a third aspect, a computer-readable storage medium is provided, characterized in that the computer-readable storage medium stores computer instructions, and when the computer instructions are executed on a computer, the computer executes the method for online high-precision alignment and maintenance of dual solar wing panels of a spacecraft as described above.

[0039] Compared with the prior art, the present invention has the following advantages:

[0040] The present invention calculates the return turning angle error of the two wing sailboards, takes the driving speed of the sun-facing sailboard as a reference, and the other wing sailboard autonomously adjusts the driving speed according to the turning angle error to align with the reference sailboard, and makes the difference between the two wing turning angles within the minimum accuracy range of the sailboard driver, thereby realizing the high-precision alignment function of the dual solar wing sailboards; the two wing sailboards after alignment perform angle maintenance control at the driving control rate of the reference sailboard, thereby realizing the maintenance function after alignment; this technology eliminates the interference caused by the turning angle error of the two wing sailboards, and can effectively improve the attitude stability of the spacecraft. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 The present invention is a flowchart of a method for aligning and maintaining the turning angles of two wing sailboards with high precision. DETAILED DESCRIPTION

[0042] The present invention proposes a method for online high-precision alignment and maintenance of dual solar wing sailboards of a spacecraft. By calculating the return angle error of the two wing sailboards, taking the driving speed of the sun-facing sailboard as a reference, the other wing sailboard autonomously adjusts the driving speed according to the angle error, aligns to the reference sailboard, and makes the difference between the two wing angles within the minimum accuracy range of the sailboard driver, thus realizing the high-precision alignment function of the dual solar wing sailboards; the aligned two wing sailboards are controlled to maintain the angle at the driving speed of the reference sailboard, thus realizing the maintenance function after alignment. This technology can eliminate the interference caused by the angle error of the two wing sailboards, and can effectively improve the attitude stability of the spacecraft.

[0043] The present invention is achieved through the following technical process:

[0044] The first step is to calculate the zero position deviation of the two wing sailboards;

[0045] The second step is to calculate the difference in the turning angles of the two wing sailboards;

[0046] The third step is to determine the direction of adjusting the driving speed of the solar wing sailboard on the back side;

[0047] The fourth step is to calculate the driving speed and adjustment time of the solar wing sailboard on the back side, and determine the control strategy of the solar wing sailboard on the back side;

[0048] The fifth step is to execute the control strategy of the fourth step. After completing the adjustment time of the fourth step, calculate the difference in the return angles of the solar wing sailboards on the back side and the sun side. After meeting the minimum accuracy requirement, the alignment of the two wing sailboards is achieved. At the same time, the driving speeds of the solar wing sailboards on the back side and the sun side are kept consistent to achieve the retention function after alignment.

[0049] The return angle refers to the angle between the solar wing sailboard and the mounting surface, which is obtained by integrating the driving speed by the driving control module in the solar wing sailboard.

[0050] The return angle of the solar wing sailboard changes with the sailboard drive control, and its range is 0~360°

[0051] Zero position refers to an initial position of the solar wing sailboard, including horizontal zero position and vertical zero position, which is determined by the zero position sensor.

[0052] Zero installation deviation refers to the deviation of the zero sensor relative to the theoretical design position during installation, which is affected by processing accuracy and assembly error.

[0053] The zero position width refers to the angular range near the zero position when the solar wing sail panel rotates. This range depends on the accuracy of the zero position sensor. The returned rotation angle within this range is the zero position value.

[0054] The driving speed refers to the rotation speed of the solar wing sailboard. Since the solar wing sailboard driver is a stepping type, MinV is its step length. The driving speed of the sun-facing sailboard and the driving speed of the sun-facing sailboard are NY_fbctrl and PY_fbctrl respectively. When tracking the sun normally, it is the orbital angular velocity ω0. For low-orbit satellites, the orbital angular velocity ω0 is between 0.06° / s and 0.07° / s, and the corresponding minimum accuracy requirement is between 0.0002 and 0.0004°.

[0055] The driving speed changes in steps upward and downward with the orbital angular velocity as the center. One step is called a gear, which is the minimum accuracy requirement for the difference in the turning angles of the two wing panels.

[0056] Alignment is the state where the corners of the two wing panels are the same.

[0057] Specifically:

[0058] 1. According to the zero-position installation deviation and zero-position width, calculate the zero-position deviation Delt_PNY of the solar wing sailboard on the back side and the sun side:

[0059] Delt_PNY=(Pylw_Offset-Kstate*Pylw_Widh*0.5)-(Nylw_Offset-Kstate*Nylw_Widh*0.5)

[0060] Wherein, Pylw_Offset and Nylw_Offset are the zero-position installation deviations of the solar wing sailboards on the back side and the sun side, respectively, which are constant values ​​and can be measured after the solar wing sailboards are installed; Pylw_Widh and Nylw_Widh are the zero-position widths of the solar wing sailboards on the back side and the sun side, respectively, which are constant values ​​and can be measured after the solar wing sailboards are installed; when the spacecraft is flying forward, Kstate = 1, and when the spacecraft is flying backward, Kstate = -1.

[0061] 2. According to the return angles of the two wing sailboards and the zero position deviation calculated in step 1, calculate the difference between the angles of the solar wing sailboards on the back side and the sun side, Delt_Sada_Agl:

[0062] Delt_Sada_Agl=PY_Sada_Agl-NY_Sada_Agl+Delt_PNY

[0063] Where PY_Sada_Agl and NY_Sada_Agl are the return angles of the solar wing sailboard on the sun-facing side and the dark side, respectively.

[0064] 3. According to the difference in the rotation angle calculated in step 2, determine the position of the solar wing sailboard on the back side relative to the sun side, and then determine the driving speed adjustment direction Addir of the solar wing sailboard on the back side:

[0065] When Delt_Sada_Agl>MinV, the solar wing sailboard on the back side needs to slow down, so Addir=-1;

[0066] When Delt_Sada_Agl<-MinV, the solar wing sailboard on the back side needs to be accelerated, so Addir=1;

[0067] When |Delt_Sada_Agl|<MinV, Addir=0

[0068] 4. Calculate the driving speed and adjustment time of the solar wing sailboard on the back side:

[0069] According to the adjustment direction Addir in the third step, the driving speed of the solar wing sailboard on the sun-facing side is used as the benchmark, and the solar wing sailboard on the back side adjusts a control gear on this basis, and the driving speed PY_fbctrl of the solar wing sailboard on the back side is calculated:

[0070] PY_fbctrl=NY_fbctrl+Addir*MinV

[0071] According to the difference in the rotation angle calculated in the second step, the adjustment time AdjustT of the driving control command of the solar wing sailboard on the back side is calculated:

[0072] AdjustT=Delt_Sada_Agl / MinV

[0073] 5. Execution control strategy

[0074] After the back-facing solar wing sailboard is driven at the driving speed PY_fbctrl for AdjustT time, the difference between the return angles of the back-facing and sun-facing solar wing sailboards, Delt_Sada_Agl, is calculated again. When |Delt_Sada_Agl|<MinV, the two sailboards are controlled within the minimum accuracy range of the sailboard driver to achieve alignment of the two sailboards. At the same time, the driving speeds of the back-facing and sun-facing solar wing sailboards are kept consistent, that is, PY_fbctrl=NY_fbctrl, to achieve the retention function after alignment.

[0075] In a second aspect, a terminal device is provided, characterized in that it includes:

[0076] a memory for storing instructions executed by at least one processor;

[0077] The processor is used to execute instructions stored in the memory to implement the online high-precision alignment and maintenance method of the dual solar wing panels of the spacecraft as described above.

[0078] According to a third aspect, a computer-readable storage medium is provided, characterized in that the computer-readable storage medium stores computer instructions, and when the computer instructions are executed on a computer, the computer executes the method for online high-precision alignment and maintenance of dual solar wing panels of a spacecraft as described above.

[0079] The contents not described in detail in the specification of the present invention belong to the prior art known to the professional and technical personnel in this field.

Claims

1. A method for online high-precision alignment and maintenance of dual solar wing sail panels of a spacecraft, characterized in that include: S1, according to the return angle PY_Sada_Agl of the sailboard on the back side and the return angle NY_Sada_Agl of the sailboard on the sun-facing wing, and combined with the zero-position installation deviation Delt_PNY of the sailboard on the solar wing, calculate the difference between the angles of the sailboards on the two wings Delt_Sada_Agl; S2, according to the calculated difference between the turning angles of the two wing sailboards Delt_Sada_Agl, determine the position of the sailboard on the back side relative to the sailboard on the sun side, and then determine the driving speed adjustment direction Addir of the sailboard on the back side; S3, taking the driving speed NY_fbctrl of the sailboard on the sun-facing side as a reference, the driving speed PY_fbctrl of the sailboard on the back-facing side is adjusted by one gear; S4, determining the adjustment time AdjustT of the driving control command of the sailboard on the back side according to the difference between the rotation angles of the two sailboards Delt_Sada_Agl obtained by the above calculation; S5, within the adjustment time AdjustT, adjust the two wing sailboards according to the driving speed of the sun-facing sailboard and the driving speed of the sun-facing sailboard set in S3; after the adjustment time AdjustT ends, calculate the difference between the rotation angles of the two wing sailboards again. If the minimum accuracy requirement is met, the return rotation angles of the two wing sailboards are consistent, and the two wing sailboards are aligned; if the minimum accuracy requirement is not met, return to S1 for recalculation; S6. After alignment, the driving speed of the back sun-facing sailboard is kept consistent with the driving speed of the sun-facing solar wing sailboard, so as to maintain the alignment of the two wing sailboards.

2. A method for online high-precision alignment and maintenance of dual solar wing panels of a spacecraft according to claim 1, characterized in that: The return angle refers to the angle between the solar wing sailboard and the mounting surface, which is obtained by integrating the driving speed of the driving control module in the solar wing sailboard; The return angle of the solar wing sailboard changes with the sailboard drive control, and its range is 0 to 360°; Zero position refers to an initial position of the solar wing sailboard, including horizontal zero position and vertical zero position, which is determined by the zero position sensor; Zero installation deviation refers to the deviation of the zero sensor relative to the theoretical design position during installation, which is affected by processing accuracy and assembly error; The driving speed of the sailboard refers to the rotation speed of the solar wing sailboard. Since the solar wing sailboard driver is a stepping type, MinV is its step length; The driving speed of the sailboard changes in steps upward and downward with the orbital angular velocity as the center. One step is called a gear, which is the minimum accuracy requirement of the difference between the turning angles of the two wings of the sailboard. Alignment is the state where the corners of the two wing panels are the same.

3. A method for online high-precision alignment and maintenance of dual solar wing panels of a spacecraft according to claim 1, characterized in that: When NY_fbctrl and PY_fbctrl track the sun normally, the orbital angular velocity ω0 is between 0.06° / s and 0.07° / s. The corresponding minimum accuracy requirement is between 0.0002° and 0.0004°.

4. A method for online high-precision alignment and maintenance of dual solar wing panels of a spacecraft according to claim 1, characterized in that: The calculation method of the solar wing sailboard zero position installation deviation Delt_PNY is: Delt_PNY = (Pylw_Offset - Kstate * Pylw_Widh * 0.5) - (Nylw_Offset - Kstate * Nylw_Widh * 0.5) In the formula, Pylw_Offset and Nylw_Offset are the zero-position installation deviations of the solar panel on the shaded side and the sunny side respectively, which are constant values and are obtained by measurement after the installation of the solar panel is completed; Pylw_Widh and Nylw_Widh are the zero-position widths of the solar panel on the shaded side and the sunny side respectively, which are constant values and are obtained by measurement after the installation of the solar panel is completed; Kstate represents the flight direction of the spacecraft. When the spacecraft is flying forward, Kstate = 1, and when the spacecraft is flying backward, Kstate = -1; 5. The method for online high-precision alignment and maintenance of dual solar wing panels of a spacecraft according to claim 1, characterized in that: The zero-position width refers to an angular range when the solar panel rotates near the zero position. This range depends on the accuracy of the zero-position sensor, and within this range, the returned rotation angle is the zero-position value. The calculation method of the rotation angle difference Delt_Sada_Agl between the solar panels on the shaded side and the sunny side is as follows:

6. A method for online high-precision alignment and maintenance of dual solar wing panels of a spacecraft according to claim 1, characterized in that: Delt_Sada_Agl = PY_Sada_Agl - NY_Sada_Agl + Delt_PNY. The calculation method of the adjustment direction Addir of the driving speed of the solar panel on the shaded side is as follows: When Delt_Sada_Agl > MinV, the solar panel on the shaded side needs to decelerate, so Addir = -1; When Delt_Sada_Agl < -MinV, the solar panel on the shaded side needs to accelerate, so Addir = 1; When |Delt_Sada_Agl| < MinV, Addir = 0; 7. A method for online high-precision alignment and maintenance of dual solar wing panels of a spacecraft according to claim 1, characterized in that: MinV is the step size of the step-type solar panel driver, that is, the gear. The calculation method of the driving speed PY_fbctrl of the solar panel on the shaded side is as follows:

8. The method for online high-precision alignment and maintenance of dual solar wing panels of a spacecraft according to claim 1, characterized in that: PY_fbctrl = NY_fbctrl + Addir * MinV. The calculation method of the adjustment time AdjustT is as follows: AdjustT = Delt_Sada_Agl / MinV 9. A terminal device, characterized in that: MinV is the step size of the step-type solar panel driver, that is, the gear. including: a memory for storing instructions executed by at least one processor; 10. A computer-readable storage medium, characterized in that: a processor for executing the instructions stored in the memory to implement the method according to any one of claims 1-8. The computer-readable storage medium stores computer instructions, and when the computer instructions run on a computer, the computer is caused to execute the method according to any one of claims 1-8.

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