A method for online high-precision alignment and maintenance of dual solar panels for spacecraft

Abstract

This invention proposes a method for online high-precision alignment and maintenance of dual solar panels in spacecraft, applicable to ultra-low orbit spacecraft with dual solar panels. By acquiring the return angles of the two solar panels and calculating their angle errors, one solar panel is used as a reference. The other solar panel autonomously adjusts its drive speed based on the angle error to align with the reference panel, thus reducing the angle error. This invention can be used for closed-loop control of the solar panels, significantly reducing aerodynamic disturbances caused by the angle errors of the two solar panels in ultra-low orbit spacecraft, and effectively improving the attitude stability of the spacecraft.

Description

Technical Field

[0001] This invention proposes a method for online high-precision alignment and maintenance of dual solar panels in spacecraft, which can be applied to ultra-low orbit spacecraft with dual solar panels and belongs to the field of satellite control. Background Technology

[0002] To acquire more diverse Earth remote sensing data, traditional spacecraft payloads that passively receive surface signals are no longer sufficient. Therefore, spacecraft payloads that actively transmit Earth-based detection signals have emerged. However, due to limitations such as transmission power, some spacecraft must operate in very low Earth orbits. To minimize aerodynamic interference caused by atmospheric drag, these spacecraft often feature a symmetrical configuration with dual solar panels. While this configuration reduces aerodynamic interference from atmospheric drag, during solar tracking, the asynchronous rotation of the two solar panels can cause sudden reversals of the interference torque at certain locations, leading to attitude fluctuations. Existing technologies achieve closed-loop control by capturing the sun when the solar panels reach zero position, neglecting the asymmetric aerodynamic interference caused by the rotation error of the two solar panels. Currently, there is no effective method for online high-precision alignment and maintenance of dual solar panels in engineering. Therefore, it is necessary to invent a method that can autonomously align and maintain the two solar panels with high precision to improve the attitude control accuracy of spacecraft. 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 panels of a spacecraft. Under the premise of ensuring that the solar panel on the sun-facing side can track the sun normally, the solar panel on the shady side can be adjusted to make the rotation angle of the two panels consistent, thereby achieving aerodynamic interference symmetry and effectively improving the attitude control accuracy of ultra-low orbit spacecraft.

[0004] The technical solution of the present invention is as follows: Firstly, a method for online high-precision alignment and maintenance of dual solar panels on a spacecraft is provided, comprising:

[0005] S1. Based on the return angle PY_Sada_Agl of the sun-facing solar panel and the return angle NY_Sada_Agl of the sun-facing solar panel, and combined with the zero-position installation deviation Delt_PNY of the solar panel, calculate the difference in angles between the two solar panels, Delt_Sada_Agl.

[0006] S2. Based on the calculated difference in the rotation angles of the two wing sails, Delt_Sada_Agl, determine the position of the sun-facing sail relative to the sun-facing sail, and then determine the direction of the drive speed adjustment of the sun-facing sail, Addir.

[0007] S3. Based on the driving speed of the sun-facing sailboard NY_fbctrl, the driving speed of the shady-facing sailboard PY_fbctrl is adjusted by one gear.

[0008] S4. Based on the difference in the rotation angles of the two wing sails obtained from the above calculation, Delt_Sada_Agl, determine the adjustment time AdjustT of the sun-facing sail drive control command.

[0009] S5. During the adjustment time AdjustT, adjust the two wing sails according to the driving speeds of the sun-facing sail and the shady sail set in S3. After the adjustment time AdjustT ends, recalculate the difference in the rotation angle of the two wing sails. If the minimum accuracy requirement is met, the return rotation angles of the two wing sails are consistent, and the two wing sails are aligned. If the minimum accuracy requirement is not met, return to S1 and recalculate.

[0010] S6. After alignment, the driving speed of the sun-facing solar panel on the back side is kept consistent with the driving speed of the sun-facing solar panel on the front side to maintain the alignment of the two solar panels.

[0011] Preferably, the return angle refers to the angle between the solar panel and the mounting surface, which is obtained by integrating the drive control module in the solar panel according to the drive speed;

[0012] The solar panel's return angle varies with the panel's drive control, ranging from 0 to 360°.

[0013] Zero position refers to an initial position of the solar panel, including horizontal and vertical zero positions, which are determined by a zero position sensor;

[0014] Zero-position installation deviation refers to the deviation of the zero-position sensor from its theoretically designed position during installation, which is affected by machining accuracy and assembly errors.

[0015] The driving speed of the solar panel refers to the rotational speed of the solar panel. Since the solar panel actuator is a stepper type, MinV is its step size.

[0016] The driving speed of the windsurfing plate changes upward and downward in steps with the track angular velocity as the center. One step is called a gear, which is the minimum precision requirement for the difference in the turning angle of the two windsurfing plates.

[0017] Alignment means that the angles of the two sails are the same.

[0018] Preferably, NY_fbctrl and PY_fbctrl are orbital angular velocities 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 for the zero-position installation deviation of the solar panel, Delt_PNY, is as follows:

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

[0021] In the formula, Pylw_Offset and Nylw_Offset are the zero-position installation deviations of the solar panels on the shaded and sun-facing sides, respectively, and are constant values ​​measured after the solar panels are installed; Pylw_Widh and Nylw_Widh are the zero-position widths of the solar panels on the shaded and sun-facing sides, respectively, and are constant values ​​measured after the solar panels are installed; Kstate represents the spacecraft's flight direction, Kstate = 1 when the spacecraft is flying forward and Kstate = -1 when the spacecraft is flying backward.

[0022] Zero-position width refers to the angular range near the zero position when the solar panel rotates. This range depends on the accuracy of the zero-position sensor. Within this range, the returned angle is the zero-position value.

[0023] Preferably, the calculation method for the difference in the rotation angle of the solar panel on the shaded side and the sun-facing side, Delt_Sada_Agl, is as follows:

[0024] Delt_Sada_Agl=PY_Sada_Agl-NY_Sada_Agl+Delt_PNY.

[0025] Preferably, the calculation method for the drive speed adjustment direction Addir of the sun-facing sail is as follows:

[0026] When Delt_Sada_Agl > MinV, the sunless sail needs to decelerate, therefore Addir = -1;

[0027] When Delt_Sada_Agl < -MinV, the sunless sail needs to accelerate, therefore Addir = 1;

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

[0029] MinV is the step size, or gear, of the stepping solar panel driver.

[0030] The preferred method for calculating the driving speed PY_fbctrl of the sun-facing sail is as follows:

[0031] PY_fbctrl=NY_fbctrl+Addir*MinV.

[0032] The preferred method for calculating the adjustment time AdjustT is as follows:

[0033] AdjustT = Delt_Sada_Agl / MinV

[0034] MinV is the step size, or gear, of the stepping solar panel driver.

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

[0036] Memory, used to store at least one instruction executed by a processor;

[0037] The processor executes instructions stored in memory to implement the online high-precision alignment and maintenance method for the spacecraft's dual solar panels as described above.

[0038] Thirdly, a computer-readable storage medium is provided, characterized in that the computer-readable storage medium stores computer instructions, which, when executed on a computer, cause the computer to perform the online high-precision alignment and holding method for spacecraft dual solar panels as described above.

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

[0040] This invention calculates the return angle error of the two solar panels, uses the driving speed of the sun-facing solar panel as a reference, and autonomously adjusts the driving speed of the other solar panel according to the angle error to align with the reference solar panel. This keeps the angle difference between the two solar panels within the minimum accuracy range of the solar panel actuator, achieving high-precision alignment of the dual solar panels. After alignment, the two solar panels maintain their angle using the driving control rate of the reference solar panel, achieving a holding function after alignment. This technology eliminates interference caused by the angle error of the two solar panels and can effectively improve the attitude stability of the spacecraft. Attached Figure Description

[0041] Figure 1 This is a flowchart of the method for high-precision alignment and maintenance of the two-wing sail angles according to the present invention. Detailed Implementation

[0042] This invention proposes a method for online high-precision alignment and maintenance of dual solar panels in spacecraft. By calculating the return angle error of the two solar panels, and using the driving speed of the sun-facing solar panel as a reference, the driving speed of the other solar panel autonomously adjusts its driving speed according to the angle error to align with the reference solar panel. This ensures that the difference in angle between the two solar panels is within the minimum precision range of the solar panel actuator, achieving high-precision alignment of the dual solar panels. After alignment, the two solar panels maintain their angle using the driving speed of the reference solar panel, thus maintaining the alignment function. This technology can eliminate interference caused by the angle error of the two solar panels and effectively improve the attitude stability of the spacecraft.

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

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

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

[0046] The third step is to determine the direction of adjustment for the drive speed of the solar panel on the shaded side.

[0047] The fourth step is to calculate the drive speed and adjustment time of the solar panel on the shady side, and determine the control strategy for the solar panel on the shady side.

[0048] The fifth step is to execute the control strategy of the fourth step. After the adjustment time of the fourth step is completed, the difference in the return angle of the sun-facing and sun-facing solar panels is calculated. After meeting the minimum accuracy requirements, the alignment of the two solar panels is achieved. At the same time, the drive speed of the sun-facing and sun-facing solar panels is kept consistent to achieve the alignment retention function.

[0049] The return angle refers to the angle between the solar panel and the mounting surface, which is obtained by integrating the drive control module in the solar panel with respect to the drive speed.

[0050] The solar panel's return angle varies with the panel's drive control, ranging from 0 to 360°.

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

[0052] Zero-position installation deviation refers to the deviation of the zero-position sensor from its theoretically designed position during installation, which is affected by machining accuracy and assembly errors.

[0053] Zero-position width refers to the angular range near the zero position when the solar panel rotates. This range depends on the accuracy of the zero-position sensor. Within this range, the returned angle is the zero-position value.

[0054] Drive speed refers to the rotational speed of the solar panel. Since the solar panel actuator is a stepper type, MinV is its step size. The drive speeds of the sun-facing solar panel and the sun-receding solar panel are NY_fbctrl and PY_fbctrl, respectively, which are the orbital angular velocity ω0 during normal solar tracking. For low Earth orbit satellites, the orbital angular velocity ω0 is between 0.06° / s and 0.07° / s, corresponding to a minimum accuracy requirement of 0.0002 to 0.0004°.

[0055] The driving speed changes upward and downward in steps centered on the orbital angular velocity. One step is called a gear, which is the minimum precision requirement for the difference in the rotation angle of the two wings.

[0056] Alignment means that the angles of the two sails are the same.

[0057] Specifically:

[0058] 1. Based on the zero-position installation deviation and zero-position width, calculate the zero-position deviation Delt_PNY between the sun-facing and sun-facing solar panels:

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

[0060] In the formula, Pylw_Offset and Nylw_Offset are the zero-position installation deviations of the solar panels on the shaded and sun-facing sides, respectively, and are constant values ​​that can be measured after the solar panels are installed; Pylw_Widh and Nylw_Widh are the zero-position widths of the solar panels on the shaded and sun-facing sides, respectively, and are constant values ​​that can be measured after the solar panels are installed; Kstate = 1 when the spacecraft is flying upright, and Kstate = -1 when the spacecraft is flying inverted.

[0061] 2. Based on the return angles of the two solar panels and the zero-position deviation calculated in step 1, calculate the difference in solar panel rotation angles (Delt_Sada_Agl) between the sun-facing and sun-facing sides:

[0062] Delt_Sada_Agl=PY_Sada_Agl-NY_Sada_Agl+Delt_PNY

[0063] In the formula, PY_Sada_Agl and NY_Sada_Agl are the return angles of the solar panels on the shaded and sun-facing sides, respectively.

[0064] 3. Based on the angle difference calculated in step 2, determine the position of the solar panel on the shaded side relative to the sunlit side, and then determine the direction of the drive speed adjustment for the solar panel on the shaded side (Addir).

[0065] When Delt_Sada_Agl > MinV, the solar panel on the dark side needs to decelerate, therefore Addir = -1;

[0066] When Delt_Sada_Agl < -MinV, the solar panels on the dark side need to accelerate, therefore Addir = 1;

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

[0068] 4. Calculate the drive speed and adjustment time of the solar panel on the shaded side:

[0069] Based on the adjustment direction Addir in step three, and using the driving speed of the sun-facing solar panel as a reference, the driving speed of the shady-facing solar panel is adjusted by one control level. The driving speed PY_fbctrl of the shady-facing solar panel is then calculated.

[0070] PY_fbctrl=NY_fbctrl+Addir*MinV

[0071] Based on the angle difference calculated in the second step, calculate the adjustment time AdjustT for the drive control command of the solar panel on the shady side:

[0072] AdjustT = Delt_Sada_Agl / MinV

[0073] 5. Implement control strategies

[0074] After the sun-facing solar panel is driven at a speed of PY_fbctrl for a time AdjustT, the difference in return angle between the sun-facing and sun-facing solar panels, Delt_Sada_Agl, is calculated again. When |Delt_Sada_Agl| < MinV, the two solar panels are controlled within the minimum precision range of the solar panel actuator, achieving alignment of the two solar panels. At the same time, the driving speeds of the sun-facing and sun-facing solar panels remain consistent, i.e., PY_fbctrl = NY_fbctrl, achieving the function of maintaining alignment.

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

[0076] Memory, used to store at least one instruction executed by a processor;

[0077] The processor executes instructions stored in memory to implement the online high-precision alignment and maintenance method for the spacecraft's dual solar panels as described above.

[0078] Thirdly, a computer-readable storage medium is provided, characterized in that the computer-readable storage medium stores computer instructions, which, when executed on a computer, cause the computer to perform the online high-precision alignment and holding method for spacecraft dual solar panels as described above.

[0079] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

Claims

1. A method for online high-precision alignment and maintenance of dual solar panels for spacecraft, characterized in that... include: S1. Based on the return angle PY_Sada_Agl of the sun-facing solar panel and the return angle NY_Sada_Agl of the sun-facing solar panel, and combined with the zero-position installation deviation Delt_PNY of the solar panel, calculate the difference in angles between the two solar panels, Delt_Sada_Agl. S2. Based on the calculated difference in the rotation angles of the two wing sails, Delt_Sada_Agl, determine the position of the sun-facing sail relative to the sun-facing sail, and then determine the direction of the drive speed adjustment of the sun-facing sail, Addir. S3. Based on the driving speed of the sun-facing sailboard NY_fbctrl, the driving speed of the shady-facing sailboard PY_fbctrl is adjusted by one gear. S4. Based on the difference in the rotation angles of the two wing sails obtained from the above calculation, Delt_Sada_Agl, determine the adjustment time AdjustT of the sun-facing sail drive control command. S5. During the adjustment time AdjustT, adjust the two wing sails according to the driving speeds of the sun-facing sail and the shady sail set in S3. After the adjustment time AdjustT ends, recalculate the difference in the rotation angle of the two wing sails. If the minimum accuracy requirement is met, the return rotation angles of the two wing sails are consistent, and the two wing sails are aligned. If the minimum accuracy requirement is not met, return to S1 and recalculate. S6. After alignment, the driving speed of the sun-facing solar panel on the back side is kept consistent with the driving speed of the sun-facing solar panel on the front side to maintain the alignment of the two solar panels. The return angle refers to the angle between the solar panel and the mounting surface, which is obtained by integrating the drive control module in the solar panel with respect to the drive speed. The solar panel's return angle varies with the panel's drive control, ranging from 0 to 360°. Zero position refers to an initial position of the solar panel, including horizontal and vertical zero positions, which are determined by a zero position sensor; Zero-position installation deviation refers to the deviation of the zero-position sensor from its theoretically designed position during installation, which is affected by machining accuracy and assembly errors. The driving speed of the solar panel refers to the rotational speed of the solar panel. Since the solar panel actuator is a stepper type, MinV is its step size. The driving speed of the windsurfing plate changes upward and downward in steps with the track angular velocity as the center. One step is called a gear, which is the minimum precision requirement for the difference in the turning angle of the two windsurfing plates. Alignment means that the angles of the two sails are the same.

2. The method for online high-precision alignment and maintenance of dual solar panels in a spacecraft according to claim 1, characterized in that: When NY_fbctrl and PY_fbctrl are tracking the sun normally, their orbital angular velocity is ω0. 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°.

3. The method for online high-precision alignment and maintenance of dual solar panels in a spacecraft according to claim 1, characterized in that: The calculation method for the zero-position installation deviation of the solar panel, Delt_PNY, is as follows: 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 panels on the shaded and sun-facing sides, respectively, and are constant values ​​measured after the solar panels are installed; Pylw_Widh and Nylw_Widh are the zero-position widths of the solar panels on the shaded and sun-facing sides, respectively, and are constant values ​​measured after the solar panels are installed; Kstate represents the spacecraft's flight direction, Kstate = 1 when the spacecraft is flying forward and Kstate = -1 when the spacecraft is flying backward. Zero-position width refers to the angular range near the zero position when the solar panel rotates. This range depends on the accuracy of the zero-position sensor. Within this range, the returned angle is the zero-position value.

4. The method for online high-precision alignment and maintenance of dual solar panels in a spacecraft according to claim 1, characterized in that: The method for calculating the difference in solar panel rotation angle between the shaded and sun-facing sides, Delt_Sada_Agl, is as follows: Delt_Sada_Agl=PY_Sada_Agl-NY_Sada_Agl+Delt_PNY.

5. The method for online high-precision alignment and maintenance of dual solar panels in a spacecraft according to claim 1, characterized in that: The calculation method for the direction of adjustment of the drive speed Addir for the sun-facing windsurfing is as follows: When Delt_Sada_Agl > MinV, the sunless sail needs to decelerate, therefore Addir = -1; When Delt_Sada_Agl < -MinV, the sunless sail needs to accelerate, therefore Addir = 1; When |Delt_Sada_Agl| < MinV, Addir = 0; MinV is the step size, or gear, of the stepping solar panel driver.

6. The method for online high-precision alignment and maintenance of dual solar panels in a spacecraft according to claim 1, characterized in that: The calculation method for the drive speed PY_fbctrl of the sun-facing sail is as follows: PY_fbctrl=NY_fbctrl+Addir*MinV.

7. The method for online high-precision alignment and maintenance of dual solar panels for spacecraft according to claim 1, characterized in that: The method for calculating the adjustment time AdjustT is as follows: AdjustT = Delt_Sada_Agl / MinV MinV is the step size, or gear, of the stepping solar panel driver.

8. A terminal device, characterized in that, include: Memory, used to store at least one instruction executed by a processor; A processor for executing instructions stored in memory to implement the method as described in any one of claims 1-7.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that, when executed on a computer, cause the computer to perform the method as described in any one of claims 1-7.

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